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• Null-free "maps": Is a callback solution slower than tryGet()?

  - by David Moles

  In comments to "How to implement List, Set, and Map in null free design?", Steven Sudit and I got into a discussion about using a callback, with handlers for "found" and "not found" situations, vs. a tryGet() method, taking an out parameter and returning a boolean indicating whether the out parameter had been populated. Steven maintained that the callback approach was more complex and almost certain to be slower; I maintained that the complexity was no greater and the performance at worst the same. But code speaks louder than words, so I thought I'd implement both and see what I got. The original question was fairly theoretical with regard to language ("And for argument sake, let's say this language don't even have null") -- I've used Java here because that's what I've got handy. Java doesn't have out parameters, but it doesn't have first-class functions either, so style-wise, it should suck equally for both approaches. (Digression: As far as complexity goes: I like the callback design because it inherently forces the user of the API to handle both cases, whereas the tryGet() design requires callers to perform their own boilerplate conditional check, which they could forget or get wrong. But having now implemented both, I can see why the tryGet() design looks simpler, at least in the short term.) First, the callback example: class CallbackMap<K, V> { private final Map<K, V> backingMap; public CallbackMap(Map<K, V> backingMap) { this.backingMap = backingMap; } void lookup(K key, Callback<K, V> handler) { V val = backingMap.get(key); if (val == null) { handler.handleMissing(key); } else { handler.handleFound(key, val); } } } interface Callback<K, V> { void handleFound(K key, V value); void handleMissing(K key); } class CallbackExample { private final Map<String, String> map; private final List<String> found; private final List<String> missing; private Callback<String, String> handler; public CallbackExample(Map<String, String> map) { this.map = map; found = new ArrayList<String>(map.size()); missing = new ArrayList<String>(map.size()); handler = new Callback<String, String>() { public void handleFound(String key, String value) { found.add(key + ": " + value); } public void handleMissing(String key) { missing.add(key); } }; } void test() { CallbackMap<String, String> cbMap = new CallbackMap<String, String>(map); for (int i = 0, count = map.size(); i < count; i++) { String key = "key" + i; cbMap.lookup(key, handler); } System.out.println(found.size() + " found"); System.out.println(missing.size() + " missing"); } } Now, the tryGet() example -- as best I understand the pattern (and I might well be wrong): class TryGetMap<K, V> { private final Map<K, V> backingMap; public TryGetMap(Map<K, V> backingMap) { this.backingMap = backingMap; } boolean tryGet(K key, OutParameter<V> valueParam) { V val = backingMap.get(key); if (val == null) { return false; } valueParam.value = val; return true; } } class OutParameter<V> { V value; } class TryGetExample { private final Map<String, String> map; private final List<String> found; private final List<String> missing; public TryGetExample(Map<String, String> map) { this.map = map; found = new ArrayList<String>(map.size()); missing = new ArrayList<String>(map.size()); } void test() { TryGetMap<String, String> tgMap = new TryGetMap<String, String>(map); for (int i = 0, count = map.size(); i < count; i++) { String key = "key" + i; OutParameter<String> out = new OutParameter<String>(); if (tgMap.tryGet(key, out)) { found.add(key + ": " + out.value); } else { missing.add(key); } } System.out.println(found.size() + " found"); System.out.println(missing.size() + " missing"); } } And finally, the performance test code: public static void main(String[] args) { int size = 200000; Map<String, String> map = new HashMap<String, String>(); for (int i = 0; i < size; i++) { String val = (i % 5 == 0) ? null : "value" + i; map.put("key" + i, val); } long totalCallback = 0; long totalTryGet = 0; int iterations = 20; for (int i = 0; i < iterations; i++) { { TryGetExample tryGet = new TryGetExample(map); long tryGetStart = System.currentTimeMillis(); tryGet.test(); totalTryGet += (System.currentTimeMillis() - tryGetStart); } System.gc(); { CallbackExample callback = new CallbackExample(map); long callbackStart = System.currentTimeMillis(); callback.test(); totalCallback += (System.currentTimeMillis() - callbackStart); } System.gc(); } System.out.println("Avg. callback: " + (totalCallback / iterations)); System.out.println("Avg. tryGet(): " + (totalTryGet / iterations)); } On my first attempt, I got 50% worse performance for callback than for tryGet(), which really surprised me. But, on a hunch, I added some garbage collection, and the performance penalty vanished. This fits with my instinct, which is that we're basically talking about taking the same number of method calls, conditional checks, etc. and rearranging them. But then, I wrote the code, so I might well have written a suboptimal or subconsicously penalized tryGet() implementation. Thoughts?

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• Red Gate Coder interviews: Alex Davies

  - by Michael Williamson

  Alex Davies has been a software engineer at Red Gate since graduating from university, and is currently busy working on .NET Demon. We talked about tackling parallel programming with his actors framework, a scientific approach to debugging, and how JavaScript is going to affect the programming languages we use in years to come. So, if we start at the start, how did you get started in programming? When I was seven or eight, I was given a BBC Micro for Christmas. I had asked for a Game Boy, but my dad thought it would be better to give me a proper computer. For a year or so, I only played games on it, but then I found the user guide for writing programs in it. I gradually started doing more stuff on it and found it fun. I liked creating. As I went into senior school I continued to write stuff on there, trying to write games that weren’t very good. I got a real computer when I was fourteen and found ways to write BASIC on it. Visual Basic to start with, and then something more interesting than that. How did you learn to program? Was there someone helping you out? Absolutely not! I learnt out of a book, or by experimenting. I remember the first time I found a loop, I was like “Oh my God! I don’t have to write out the same line over and over and over again any more. It’s amazing!” When did you think this might be something that you actually wanted to do as a career? For a long time, I thought it wasn’t something that you would do as a career, because it was too much fun to be a career. I thought I’d do chemistry at university and some kind of career based on chemical engineering. And then I went to a careers fair at school when I was seventeen or eighteen, and it just didn’t interest me whatsoever. I thought “I could be a programmer, and there’s loads of money there, and I’m good at it, and it’s fun”, but also that I shouldn’t spoil my hobby. Now I don’t really program in my spare time any more, which is a bit of a shame, but I program all the rest of the time, so I can live with it. Do you think you learnt much about programming at university? Yes, definitely! I went into university knowing how to make computers do anything I wanted them to do. However, I didn’t have the language to talk about algorithms, so the algorithms course in my first year was massively important. Learning other language paradigms like functional programming was really good for breadth of understanding. Functional programming influences normal programming through design rather than actually using it all the time. I draw inspiration from it to write imperative programs which I think is actually becoming really fashionable now, but I’ve been doing it for ages. I did it first! There were also some courses on really odd programming languages, a bit of Prolog, a little bit of C. Having a little bit of each of those is something that I would have never done on my own, so it was important. And then there are knowledge-based courses which are about not programming itself but things that have been programmed like TCP. Those are really important for examples for how to approach things. Did you do any internships while you were at university? Yeah, I spent both of my summers at the same company. I thought I could code well before I went there. Looking back at the crap that I produced, it was only surpassed in its crappiness by all of the other code already in that company. I’m so much better at writing nice code now than I used to be back then. Was there just not a culture of looking after your code? There was, they just didn’t hire people for their abilities in that area. They hired people for raw IQ. The first indicator of it going wrong was that they didn’t have any computer scientists, which is a bit odd in a programming company. But even beyond that they didn’t have people who learnt architecture from anyone else. Most of them had started straight out of university, so never really had experience or mentors to learn from. There wasn’t the experience to draw from to teach each other. In the second half of my second internship, I was being given tasks like looking at new technologies and teaching people stuff. Interns shouldn’t be teaching people how to do their jobs! All interns are going to have little nuggets of things that you don’t know about, but they shouldn’t consistently be the ones who know the most. It’s not a good environment to learn. I was going to ask how you found working with people who were more experienced than you… When I reached Red Gate, I found some people who were more experienced programmers than me, and that was difficult. I’ve been coding since I was tiny. At university there were people who were cleverer than me, but there weren’t very many who were more experienced programmers than me. During my internship, I didn’t find anyone who I classed as being a noticeably more experienced programmer than me. So, it was a shock to the system to have valid criticisms rather than just formatting criticisms. However, Red Gate’s not so big on the actual code review, at least it wasn’t when I started. We did an entire product release and then somebody looked over all of the UI of that product which I’d written and say what they didn’t like. By that point, it was way too late and I’d disagree with them. Do you think the lack of code reviews was a bad thing? I think if there’s going to be any oversight of new people, then it should be continuous rather than chunky. For me I don’t mind too much, I could go out and get oversight if I wanted it, and in those situations I felt comfortable without it. If I was managing the new person, then maybe I’d be keener on oversight and then the right way to do it is continuously and in very, very small chunks. Have you had any significant projects you’ve worked on outside of a job? When I was a teenager I wrote all sorts of stuff. I used to write games, I derived how to do isomorphic projections myself once. I didn’t know what the word was so I couldn’t Google for it, so I worked it out myself. It was horrifically complicated. But it sort of tailed off when I started at university, and is now basically zero. If I do side-projects now, they tend to be work-related side projects like my actors framework, NAct, which I started in a down tools week. Could you explain a little more about NAct? It is a little C# framework for writing parallel code more easily. Parallel programming is difficult when you need to write to shared data. Sometimes parallel programming is easy because you don’t need to write to shared data. When you do need to access shared data, you could just have your threads pile in and do their work, but then you would screw up the data because the threads would trample on each other’s toes. You could lock, but locks are really dangerous if you’re using more than one of them. You get interactions like deadlocks, and that’s just nasty. Actors instead allows you to say this piece of data belongs to this thread of execution, and nobody else can read it. If you want to read it, then ask that thread of execution for a piece of it by sending a message, and it will send the data back by a message. And that avoids deadlocks as long as you follow some obvious rules about not making your actors sit around waiting for other actors to do something. There are lots of ways to write actors, NAct allows you to do it as if it was method calls on other objects, which means you get all the strong type-safety that C# programmers like. Do you think that this is suitable for the majority of parallel programming, or do you think it’s only suitable for specific cases? It’s suitable for most difficult parallel programming. If you’ve just got a hundred web requests which are all independent of each other, then I wouldn’t bother because it’s easier to just spin them up in separate threads and they can proceed independently of each other. But where you’ve got difficult parallel programming, where you’ve got multiple threads accessing multiple bits of data in multiple ways at different times, then actors is at least as good as all other ways, and is, I reckon, easier to think about. When you’re using actors, you presumably still have to write your code in a different way from you would otherwise using single-threaded code. You can’t use actors with any methods that have return types, because you’re not allowed to call into another actor and wait for it. If you want to get a piece of data out of another actor, then you’ve got to use tasks so that you can use “async” and “await” to await asynchronously for it. But other than that, you can still stick things in classes so it’s not too different really. Rather than having thousands of objects with mutable state, you can use component-orientated design, where there are only a few mutable classes which each have a small number of instances. Then there can be thousands of immutable objects. If you tend to do that anyway, then actors isn’t much of a jump. If I’ve already built my system without any parallelism, how hard is it to add actors to exploit all eight cores on my desktop? Usually pretty easy. If you can identify even one boundary where things look like messages and you have components where some objects live on one side and these other objects live on the other side, then you can have a granddaddy object on one side be an actor and it will parallelise as it goes across that boundary. Not too difficult. If we do get 1000-core desktop PCs, do you think actors will scale up? It’s hard. There are always in the order of twenty to fifty actors in my whole program because I tend to write each component as actors, and I tend to have one instance of each component. So this won’t scale to a thousand cores. What you can do is write data structures out of actors. I use dictionaries all over the place, and if you need a dictionary that is going to be accessed concurrently, then you could build one of those out of actors in no time. You can use queuing to marshal requests between different slices of the dictionary which are living on different threads. So it’s like a distributed hash table but all of the chunks of it are on the same machine. That means that each of these thousand processors has cached one small piece of the dictionary. I reckon it wouldn’t be too big a leap to start doing proper parallelism. Do you think it helps if actors get baked into the language, similarly to Erlang? Erlang is excellent in that it has thread-local garbage collection. C# doesn’t, so there’s a limit to how well C# actors can possibly scale because there’s a single garbage collected heap shared between all of them. When you do a global garbage collection, you’ve got to stop all of the actors, which is seriously expensive, whereas in Erlang garbage collections happen per-actor, so they’re insanely cheap. However, Erlang deviated from all the sensible language design that people have used recently and has just come up with crazy stuff. You can definitely retrofit thread-local garbage collection to .NET, and then it’s quite well-suited to support actors, even if it’s not baked into the language. Speaking of language design, do you have a favourite programming language? I’ll choose a language which I’ve never written before. I like the idea of Scala. It sounds like C#, only with some of the niggles gone. I enjoy writing static types. It means you don’t have to writing tests so much. When you say it doesn’t have some of the niggles? C# doesn’t allow the use of a property as a method group. It doesn’t have Scala case classes, or sum types, where you can do a switch statement and the compiler checks that you’ve checked all the cases, which is really useful in functional-style programming. Pattern-matching, in other words. That’s actually the major niggle. C# is pretty good, and I’m quite happy with C#. And what about going even further with the type system to remove the need for tests to something like Haskell? Or is that a step too far? I’m quite a pragmatist, I don’t think I could deal with trying to write big systems in languages with too few other users, especially when learning how to structure things. I just don’t know anyone who can teach me, and the Internet won’t teach me. That’s the main reason I wouldn’t use it. If I turned up at a company that writes big systems in Haskell, I would have no objection to that, but I wouldn’t instigate it. What about things in C#? For instance, there’s contracts in C#, so you can try to statically verify a bit more about your code. Do you think that’s useful, or just not worthwhile? I’ve not really tried it. My hunch is that it needs to be built into the language and be quite mathematical for it to work in real life, and that doesn’t seem to have ended up true for C# contracts. I don’t think anyone who’s tried them thinks they’re any good. I might be wrong. On a slightly different note, how do you like to debug code? I think I’m quite an odd debugger. I use guesswork extremely rarely, especially if something seems quite difficult to debug. I’ve been bitten spending hours and hours on guesswork and not being scientific about debugging in the past, so now I’m scientific to a fault. What I want is to see the bug happening in the debugger, to step through the bug happening. To watch the program going from a valid state to an invalid state. When there’s a bug and I can’t work out why it’s happening, I try to find some piece of evidence which places the bug in one section of the code. From that experiment, I binary chop on the possible causes of the bug. I suppose that means binary chopping on places in the code, or binary chopping on a stage through a processing cycle. Basically, I’m very stupid about how I debug. I won’t make any guesses, I won’t use any intuition, I will only identify the experiment that’s going to binary chop most effectively and repeat rather than trying to guess anything. I suppose it’s quite top-down. Is most of the time then spent in the debugger? Absolutely, if at all possible I will never debug using print statements or logs. I don’t really hold much stock in outputting logs. If there’s any bug which can be reproduced locally, I’d rather do it in the debugger than outputting logs. And with SmartAssembly error reporting, there’s not a lot that can’t be either observed in an error report and just fixed, or reproduced locally. And in those other situations, maybe I’ll use logs. But I hate using logs. You stare at the log, trying to guess what’s going on, and that’s exactly what I don’t like doing. You have to just look at it and see does this look right or wrong. We’ve covered how you get to grip with bugs. How do you get to grips with an entire codebase? I watch it in the debugger. I find little bugs and then try to fix them, and mostly do it by watching them in the debugger and gradually getting an understanding of how the code works using my process of binary chopping. I have to do a lot of reading and watching code to choose where my slicing-in-half experiment is going to be. The last time I did it was SmartAssembly. The old code was a complete mess, but at least it did things top to bottom. There wasn’t too much of some of the big abstractions where flow of control goes all over the place, into a base class and back again. Code’s really hard to understand when that happens. So I like to choose a little bug and try to fix it, and choose a bigger bug and try to fix it. Definitely learn by doing. I want to always have an aim so that I get a little achievement after every few hours of debugging. Once I’ve learnt the codebase I might be able to fix all the bugs in an hour, but I’d rather be using them as an aim while I’m learning the codebase. If I was a maintainer of a codebase, what should I do to make it as easy as possible for you to understand? Keep distinct concepts in different places. And name your stuff so that it’s obvious which concepts live there. You shouldn’t have some variable that gets set miles up the top of somewhere, and then is read miles down to choose some later behaviour. I’m talking from a very much SmartAssembly point of view because the old SmartAssembly codebase had tons and tons of these things, where it would read some property of the code and then deal with it later. Just thousands of variables in scope. Loads of things to think about. If you can keep concepts separate, then it aids me in my process of fixing bugs one at a time, because each bug is going to more or less be understandable in the one place where it is. And what about tests? Do you think they help at all? I’ve never had the opportunity to learn a codebase which has had tests, I don’t know what it’s like! What about when you’re actually developing? How useful do you find tests in finding bugs or regressions? Finding regressions, absolutely. Running bits of code that would be quite hard to run otherwise, definitely. It doesn’t happen very often that a test finds a bug in the first place. I don’t really buy nebulous promises like tests being a good way to think about the spec of the code. My thinking goes something like “This code works at the moment, great, ship it! Ah, there’s a way that this code doesn’t work. Okay, write a test, demonstrate that it doesn’t work, fix it, use the test to demonstrate that it’s now fixed, and keep the test for future regressions.” The most valuable tests are for bugs that have actually happened at some point, because bugs that have actually happened at some point, despite the fact that you think you’ve fixed them, are way more likely to appear again than new bugs are. Does that mean that when you write your code the first time, there are no tests? Often. The chance of there being a bug in a new feature is relatively unaffected by whether I’ve written a test for that new feature because I’m not good enough at writing tests to think of bugs that I would have written into the code. So not writing regression tests for all of your code hasn’t affected you too badly? There are different kinds of features. Some of them just always work, and are just not flaky, they just continue working whatever you throw at them. Maybe because the type-checker is particularly effective around them. Writing tests for those features which just tend to always work is a waste of time. And because it’s a waste of time I’ll tend to wait until a feature has demonstrated its flakiness by having bugs in it before I start trying to test it. You can get a feel for whether it’s going to be flaky code as you’re writing it. I try to write it to make it not flaky, but there are some things that are just inherently flaky. And very occasionally, I’ll think “this is going to be flaky” as I’m writing, and then maybe do a test, but not most of the time. How do you think your programming style has changed over time? I’ve got clearer about what the right way of doing things is. I used to flip-flop a lot between different ideas. Five years ago I came up with some really good ideas and some really terrible ideas. All of them seemed great when I thought of them, but they were quite diverse ideas, whereas now I have a smaller set of reliable ideas that are actually good for structuring code. So my code is probably more similar to itself than it used to be back in the day, when I was trying stuff out. I’ve got more disciplined about encapsulation, I think. There are operational things like I use actors more now than I used to, and that forces me to use immutability more than I used to. The first code that I wrote in Red Gate was the memory profiler UI, and that was an actor, I just didn’t know the name of it at the time. I don’t really use object-orientation. By object-orientation, I mean having n objects of the same type which are mutable. I want a constant number of objects that are mutable, and they should be different types. I stick stuff in dictionaries and then have one thing that owns the dictionary and puts stuff in and out of it. That’s definitely a pattern that I’ve seen recently. I think maybe I’m doing functional programming. Possibly. It’s plausible. If you had to summarise the essence of programming in a pithy sentence, how would you do it? Programming is the form of art that, without losing any of the beauty of architecture or fine art, allows you to produce things that people love and you make money from. So you think it’s an art rather than a science? It’s a little bit of engineering, a smidgeon of maths, but it’s not science. Like architecture, programming is on that boundary between art and engineering. If you want to do it really nicely, it’s mostly art. You can get away with doing architecture and programming entirely by having a good engineering mind, but you’re not going to produce anything nice. You’re not going to have joy doing it if you’re an engineering mind. Architects who are just engineering minds are not going to enjoy their job. I suppose engineering is the foundation on which you build the art. Exactly. How do you think programming is going to change over the next ten years? There will be an unfortunate shift towards dynamically-typed languages, because of JavaScript. JavaScript has an unfair advantage. JavaScript’s unfair advantage will cause more people to be exposed to dynamically-typed languages, which means other dynamically-typed languages crop up and the best features go into dynamically-typed languages. Then people conflate the good features with the fact that it’s dynamically-typed, and more investment goes into dynamically-typed languages. They end up better, so people use them. What about the idea of compiling other languages, possibly statically-typed, to JavaScript? It’s a reasonable idea. I would like to do it, but I don’t think enough people in the world are going to do it to make it pick up. The hordes of beginners are the lifeblood of a language community. They are what makes there be good tools and what makes there be vibrant community websites. And any particular thing which is the same as JavaScript only with extra stuff added to it, although it might be technically great, is not going to have the hordes of beginners. JavaScript is always to be quickest and easiest way for a beginner to start programming in the browser. And dynamically-typed languages are great for beginners. Compilers are pretty scary and beginners don’t write big code. And having your errors come up in the same place, whether they’re statically checkable errors or not, is quite nice for a beginner. If someone asked me to teach them some programming, I’d teach them JavaScript. If dynamically-typed languages are great for beginners, when do you think the benefits of static typing start to kick in? The value of having a statically typed program is in the tools that rely on the static types to produce a smooth IDE experience rather than actually telling me my compile errors. And only once you’re experienced enough a programmer that having a really smooth IDE experience makes a blind bit of difference, does static typing make a blind bit of difference. So it’s not really about size of codebase. If I go and write up a tiny program, I’m still going to get value out of writing it in C# using ReSharper because I’m experienced with C# and ReSharper enough to be able to write code five times faster if I have that help. Any other visions of the future? Nobody’s going to use actors. Because everyone’s going to be running on single-core VMs connected over network-ready protocols like JSON over HTTP. So, parallelism within one operating system is going to die. But until then, you should use actors. More Red Gater Coder interviews

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• Facing Null Pointer Exception while using BIRT

  - by srikanth

  Hi, I am using BIRT APIs in a java program.My code is : package com.tecnotree.mdx.product.utils; import java.util.HashMap; import java.util.logging.Level; import org.eclipse.birt.core.exception.BirtException; import org.eclipse.birt.core.framework.Platform; import org.eclipse.birt.report.engine.api.EngineConfig; import org.eclipse.birt.report.engine.api.EngineConstants; import org.eclipse.birt.report.engine.api.HTMLRenderOption; import org.eclipse.birt.report.engine.api.IReportEngine; import org.eclipse.birt.report.engine.api.IReportEngineFactory; import org.eclipse.birt.report.engine.api.IReportRunnable; import org.eclipse.birt.report.engine.api.IRunAndRenderTask; import org.eclipse.birt.report.engine.api.ReportEngine; public class ExampleReport { public static void main(String[] args) { // Variables used to control BIRT Engine instance ReportEngine eng = null; IReportRunnable design = null; IRunAndRenderTask task = null; HTMLRenderOption renderContext = null; HashMap contextMap = null; HTMLRenderOption options = null; final EngineConfig conf = new EngineConfig(); conf .setEngineHome("C:\\birt-runtime-2_5_2\\birt-runtime-2_5_2\\ReportEngine"); System.out.println("conf " + conf.getBIRTHome()); conf.setLogConfig(null, Level.FINE); try { Platform.startup(conf); } catch (BirtException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } IReportEngineFactory factory = (IReportEngineFactory) Platform .createFactoryObject(IReportEngineFactory.EXTENSION_REPORT_ENGINE_FACTORY); System.out.println("Factory : " + factory.toString()); System.out.println(conf.toString()); IReportEngine engine = factory.createReportEngine(conf); System.out.println("Engine : " + engine); try { design = eng .openReportDesign("C:\\birt-runtime-2_5_2\\birt-runtime-2_5_2\\ReportEngine\\samples\\hello_world.rptdesign"); } catch (Exception e) { System.err .println("An error occured during the opening of the report file!"); e.printStackTrace(); System.exit(-1); } task = eng.createRunAndRenderTask(design); renderContext = new HTMLRenderOption(); renderContext.setImageDirectory("image"); contextMap = new HashMap(); contextMap.put(EngineConstants.APPCONTEXT_HTML_RENDER_CONTEXT, renderContext); task.setAppContext(contextMap); options = new HTMLRenderOption(); options.setOutputFileName("c:/temp/output.html"); options.setOutputFormat("html"); task.setRenderOption(options); try { task.run(); } catch (Exception e) { System.err.println("An error occured while running the report!"); e.printStackTrace(); System.exit(-1); } System.out.println("All went well. Closing program!"); eng.destroy(); } } But i am facing NullPointerException while creating the report. STACKTRACE : Exception in thread "main" java.lang.NullPointerException at org.eclipse.birt.report.engine.api.impl.ReportEngine$EngineExtensionManager.<init>(ReportEngine.java:784) at org.eclipse.birt.report.engine.api.impl.ReportEngine.<init>(ReportEngine.java:109) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory$1.run(ReportEngineFactory.java:18) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory$1.run(ReportEngineFactory.java:1) at java.security.AccessController.doPrivileged(Native Method) at org.eclipse.birt.report.engine.api.impl.ReportEngineFactory.createReportEngine(ReportEngineFactory.java:14) at com.tecnotree.mdx.product.utils.ExampleReport.main(ExampleReport.java:47) Please help me regarding this... my project deadline has been reached... Appreciate your Reply Thanks in Advance

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• Asp.net mvc, view with multiple updatable parts - how?

  - by DerDres

  I have started doing asp.net mvc programming and like it more everyday. Most of the examples I have seen use separate views for viewing and editing details of a specific entity. E.g. - table of music albums linking to separate 'detail' and 'update' views [Action] | Title | Artist detail, update | Uuuh Baby | Barry White detail, update | Mr Mojo | Barry White With mvc how can I achieve a design where the R and the U (CRUD) are represented in a single view, and furthermore where the user can edit separate parts of the view, thus limiting the amount of data the user can edit before saving? Example mockup - editing album detials: I have achieved such a design with ajax calls, but Im curious how to do this without ajax. Parts of my own take on this can be seen below. I use a flag (enum EditCode) indicating which part of the view, if any, that has to render a form. Is such a design in accordance with the framework, could it be done more elegantly? AlbumController public class AlbumController : Controller { public ActionResult Index() { var albumDetails = from ManageVM in state.AlbumState.ToList() select ManageVM.Value.Detail; return View(albumDetails); } public ActionResult Manage(int albumId, EditCode editCode) { (state.AlbumState[albumId] as ManageVM).EditCode = (EditCode)editCode; ViewData["albumId"] = albumId; return View(state.AlbumState[albumId]); } [HttpGet] public ActionResult Edit(int albumId, EditCode editCode) { return RedirectToAction("Manage", new { albumId = albumId, editCode = editCode }); } // edit album details [HttpPost] public ActionResult EditDetail(int albumId, Detail details) { (state.AlbumState[albumId] as ManageVM).Detail = details; return RedirectToAction("Manage", new { albumId = albumId, editCode = EditCode.NoEdit });// zero being standard } // edit album thought [HttpPost] public ActionResult EditThoughts(int albumId, List<Thought> thoughts) { (state.AlbumState[albumId] as ManageVM).Thoughts = thoughts; return RedirectToAction("Manage", new { albumId = albumId, editCode = EditCode.NoEdit });// zero being standard } Flag - EditCode public enum EditCode { NoEdit, Details, Genres, Thoughts } Mangae view <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<MvcApplication1.Controllers.ManageVM>" %> <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> Manage </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> <h2>Manage</h2> <% if(Model.EditCode == MvcApplication1.Controllers.EditCode.Details) {%> <% Html.RenderPartial("_EditDetails", Model.Detail); %> <% }else{%> <% Html.RenderPartial("_ShowDetails", Model.Detail); %> <% } %> <hr /> <% if(Model.EditCode == MvcApplication1.Controllers.EditCode.Thoughts) {%> <% Html.RenderPartial("_EditThoughts", Model.Thoughts); %> <% }else{%> <% Html.RenderPartial("_ShowThoughts", Model.Thoughts); %> <% } %>

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• Defend PHP; convince me it isn't horrible

  - by Jason L

  I made a tongue-in-cheek comment in another question thread calling PHP a terrible language and it got down-voted like crazy. Apparently there are lots of people here who love PHP. So I'm genuinely curious. What am I missing? What makes PHP a good language? Here are my reasons for disliking it: PHP has inconsistent naming of built-in and library functions. Predictable naming patterns are important in any design. PHP has inconsistent parameter ordering of built-in functions, eg array_map vs. array_filter which is annoying in the simple cases and raises all sorts of unexpected behaviour or worse. The PHP developers constantly deprecate built-in functions and lower-level functionality. A good example is when they deprecated pass-by-reference for functions. This created a nightmare for anyone doing, say, function callbacks. A lack of consideration in redesign. The above deprecation eliminated the ability to, in many cases, provide default keyword values for functions. They fixed this in PHP 5, but they deprecated the pass-by-reference in PHP 4! Poor execution of name spaces (formerly no name spaces at all). Now that name spaces exist, what do we use as the dereference character? Backslash! The character used universally for escaping, even in PHP! Overly-broad implicit type conversion leads to bugs. I have no problem with implicit conversions of, say, float to integer or back again. But PHP (last I checked) will happily attempt to magically convert an array to an integer. Poor recursion performance. Recursion is a fundamentally important tool for writing in any language; it can make complex algorithms far simpler. Poor support is inexcusable. Functions are case insensitive. I have no idea what they were thinking on this one. A programming language is a way to specify behavior to both a computer and a reader of the code without ambiguity. Case insensitivity introduces much ambiguity. PHP encourages (practically requires) a coupling of processing with presentation. Yes, you can write PHP that doesn't do so, but it's actually easier to write code in the incorrect (from a sound design perspective) manner. PHP performance is abysmal without caching. Does anyone sell a commercial caching product for PHP? Oh, look, the designers of PHP do. Worst of all, PHP convinces people that designing web applications is easy. And it does indeed make much of the effort involved much easier. But the fact is, designing a web application that is both secure and efficient is a very difficult task. By convincing so many to take up programming, PHP has taught an entire subgroup of programmers bad habits and bad design. It's given them access to capabilities that they lack the understanding to use safely. This has led to PHP's reputation as being insecure. (However, I will readily admit that PHP is no more or less secure than any other web programming language.) What is it that I'm missing about PHP? I'm seeing an organically-grown, poorly-managed mess of a language that's spawning poor programmers. So convince me otherwise!

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• Resolving a Forward Declaration Issue Involving a State Machine in C++

  - by hypersonicninja

  I've recently returned to C++ development after a hiatus, and have a question regarding implementation of the State Design Pattern. I'm using the vanilla pattern, exactly as per the GoF book. My problem is that the state machine itself is based on some hardware used as part of an embedded system - so the design is fixed and can't be changed. This results in a circular dependency between two of the states (in particular), and I'm trying to resolve this. Here's the simplified code (note that I tried to resolve this by using headers as usual but still had problems - I've omitted them in this code snippet): #include <iostream> #include <memory> using namespace std; class Context { public: friend class State; Context() { } private: State* m_state; }; class State { public: State() { } virtual void Trigger1() = 0; virtual void Trigger2() = 0; }; class LLT : public State { public: LLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class ALL : public State { public: ALL() { } void Trigger1() { new LLT(); } void Trigger2() { new DH(); } }; // DL needs to 'know' about DH. class DL : public State { public: DL() { } void Trigger1() { new ALL(); } void Trigger2() { new DH(); } }; class HLT : public State { public: HLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class AHL : public State { public: AHL() { } void Trigger1() { new DH(); } void Trigger2() { new HLT(); } }; // DH needs to 'know' about DL. class DH : public State { public: DH () { } void Trigger1() { new AHL(); } void Trigger2() { new DL(); } }; int main() { auto_ptr<LLT> llt (new LLT); auto_ptr<ALL> all (new ALL); auto_ptr<DL> dl (new DL); auto_ptr<HLT> hlt (new HLT); auto_ptr<AHL> ahl (new AHL); auto_ptr<DH> dh (new DH); return 0; } The problem is basically that in the State Pattern, state transitions are made by invoking the the ChangeState method in the Context class, which invokes the constructor of the next state. Because of the circular dependency, I can't invoke the constructor because it's not possible to pre-define both of the constructors of the 'problem' states. I had a look at this article, and the template method which seemed to be the ideal solution - but it doesn't compile and my knowledge of templates is a rather limited... The other idea I had is to try and introduce a Helper class to the subclassed states, via multiple inheritance, to see if it's possible to specify the base class's constructor and have a reference to the state subclasse's constructor. But I think that was rather ambitious... Finally, would a direct implmentation of the Factory Method Design Pattern be the best way to resolve the entire problem?

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• understanding evaluation function

  - by mish

  I am developing a chess program. And have made use of an alpha beta algorithm and a static evaluation function. I have successfully implemented both but I want to improve the evaluation function by automatically tuning the weights assigned to its features. At this point am totally confused about the policy suitable for updating the weights of the function. One policy I have in mind is to check whether a move is good or bad before updating weights but I really know how to implement it. Thus I need ideas and pseudo code please.

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• jQuery Templates and Data Linking (and Microsoft contributing to jQuery)

  - by ScottGu

  The jQuery library has a passionate community of developers, and it is now the most widely used JavaScript library on the web today. Two years ago I announced that Microsoft would begin offering product support for jQuery, and that we’d be including it in new versions of Visual Studio going forward. By default, when you create new ASP.NET Web Forms and ASP.NET MVC projects with VS 2010 you’ll find jQuery automatically added to your project. A few weeks ago during my second keynote at the MIX 2010 conference I announced that Microsoft would also begin contributing to the jQuery project.  During the talk, John Resig -- the creator of the jQuery library and leader of the jQuery developer team – talked a little about our participation and discussed an early prototype of a new client templating API for jQuery. In this blog post, I’m going to talk a little about how my team is starting to contribute to the jQuery project, and discuss some of the specific features that we are working on such as client-side templating and data linking (data-binding). Contributing to jQuery jQuery has a fantastic developer community, and a very open way to propose suggestions and make contributions.  Microsoft is following the same process to contribute to jQuery as any other member of the community. As an example, when working with the jQuery community to improve support for templating to jQuery my team followed the following steps: We created a proposal for templating and posted the proposal to the jQuery developer forum (http://forum.jquery.com/topic/jquery-templates-proposal and http://forum.jquery.com/topic/templating-syntax ). After receiving feedback on the forums, the jQuery team created a prototype for templating and posted the prototype at the Github code repository (http://github.com/jquery/jquery-tmpl ). We iterated on the prototype, creating a new fork on Github of the templating prototype, to suggest design improvements. Several other members of the community also provided design feedback by forking the templating code. There has been an amazing amount of participation by the jQuery community in response to the original templating proposal (over 100 posts in the jQuery forum), and the design of the templating proposal has evolved significantly based on community feedback. The jQuery team is the ultimate determiner on what happens with the templating proposal – they might include it in jQuery core, or make it an official plugin, or reject it entirely.  My team is excited to be able to participate in the open source process, and make suggestions and contributions the same way as any other member of the community. jQuery Template Support Client-side templates enable jQuery developers to easily generate and render HTML UI on the client.  Templates support a simple syntax that enables either developers or designers to declaratively specify the HTML they want to generate.  Developers can then programmatically invoke the templates on the client, and pass JavaScript objects to them to make the content rendered completely data driven.  These JavaScript objects can optionally be based on data retrieved from a server. Because the jQuery templating proposal is still evolving in response to community feedback, the final version might look very different than the version below. This blog post gives you a sense of how you can try out and use templating as it exists today (you can download the prototype by the jQuery core team at http://github.com/jquery/jquery-tmpl or the latest submission from my team at http://github.com/nje/jquery-tmpl).  jQuery Client Templates You create client-side jQuery templates by embedding content within a <script type="text/html"> tag.  For example, the HTML below contains a <div> template container, as well as a client-side jQuery “contactTemplate” template (within the <script type="text/html"> element) that can be used to dynamically display a list of contacts: The {{= name }} and {{= phone }} expressions are used within the contact template above to display the names and phone numbers of “contact” objects passed to the template. We can use the template to display either an array of JavaScript objects or a single object. The JavaScript code below demonstrates how you can render a JavaScript array of “contact” object using the above template. The render() method renders the data into a string and appends the string to the “contactContainer” DIV element: When the page is loaded, the list of contacts is rendered by the template.  All of this template rendering is happening on the client-side within the browser:   Templating Commands and Conditional Display Logic The current templating proposal supports a small set of template commands - including if, else, and each statements. The number of template commands was deliberately kept small to encourage people to place more complicated logic outside of their templates. Even this small set of template commands is very useful though. Imagine, for example, that each contact can have zero or more phone numbers. The contacts could be represented by the JavaScript array below: The template below demonstrates how you can use the if and each template commands to conditionally display and loop the phone numbers for each contact: If a contact has one or more phone numbers then each of the phone numbers is displayed by iterating through the phone numbers with the each template command: The jQuery team designed the template commands so that they are extensible. If you have a need for a new template command then you can easily add new template commands to the default set of commands. Support for Client Data-Linking The ASP.NET team recently submitted another proposal and prototype to the jQuery forums (http://forum.jquery.com/topic/proposal-for-adding-data-linking-to-jquery). This proposal describes a new feature named data linking. Data Linking enables you to link a property of one object to a property of another object - so that when one property changes the other property changes.  Data linking enables you to easily keep your UI and data objects synchronized within a page. If you are familiar with the concept of data-binding then you will be familiar with data linking (in the proposal, we call the feature data linking because jQuery already includes a bind() method that has nothing to do with data-binding). Imagine, for example, that you have a page with the following HTML <input> elements: The following JavaScript code links the two INPUT elements above to the properties of a JavaScript “contact” object that has a “name” and “phone” property: When you execute this code, the value of the first INPUT element (#name) is set to the value of the contact name property, and the value of the second INPUT element (#phone) is set to the value of the contact phone property. The properties of the contact object and the properties of the INPUT elements are also linked – so that changes to one are also reflected in the other. Because the contact object is linked to the INPUT element, when you request the page, the values of the contact properties are displayed: More interesting, the values of the linked INPUT elements will change automatically whenever you update the properties of the contact object they are linked to. For example, we could programmatically modify the properties of the “contact” object using the jQuery attr() method like below: Because our two INPUT elements are linked to the “contact” object, the INPUT element values will be updated automatically (without us having to write any code to modify the UI elements): Note that we updated the contact object above using the jQuery attr() method. In order for data linking to work, you must use jQuery methods to modify the property values. Two Way Linking The linkBoth() method enables two-way data linking. The contact object and INPUT elements are linked in both directions. When you modify the value of the INPUT element, the contact object is also updated automatically. For example, the following code adds a client-side JavaScript click handler to an HTML button element. When you click the button, the property values of the contact object are displayed using an alert() dialog: The following demonstrates what happens when you change the value of the Name INPUT element and click the Save button. Notice that the name property of the “contact” object that the INPUT element was linked to was updated automatically: The above example is obviously trivially simple.  Instead of displaying the new values of the contact object with a JavaScript alert, you can imagine instead calling a web-service to save the object to a database. The benefit of data linking is that it enables you to focus on your data and frees you from the mechanics of keeping your UI and data in sync. Converters The current data linking proposal also supports a feature called converters. A converter enables you to easily convert the value of a property during data linking. For example, imagine that you want to represent phone numbers in a standard way with the “contact” object phone property. In particular, you don’t want to include special characters such as ()- in the phone number - instead you only want digits and nothing else. In that case, you can wire-up a converter to convert the value of an INPUT element into this format using the code below: Notice above how a converter function is being passed to the linkFrom() method used to link the phone property of the “contact” object with the value of the phone INPUT element. This convertor function strips any non-numeric characters from the INPUT element before updating the phone property.  Now, if you enter the phone number (206) 555-9999 into the phone input field then the value 2065559999 is assigned to the phone property of the contact object: You can also use a converter in the opposite direction also. For example, you can apply a standard phone format string when displaying a phone number from a phone property. Combining Templating and Data Linking Our goal in submitting these two proposals for templating and data linking is to make it easier to work with data when building websites and applications with jQuery. Templating makes it easier to display a list of database records retrieved from a database through an Ajax call. Data linking makes it easier to keep the data and user interface in sync for update scenarios. Currently, we are working on an extension of the data linking proposal to support declarative data linking. We want to make it easy to take advantage of data linking when using a template to display data. For example, imagine that you are using the following template to display an array of product objects: Notice the {{link name}} and {{link price}} expressions. These expressions enable declarative data linking between the SPAN elements and properties of the product objects. The current jQuery templating prototype supports extending its syntax with custom template commands. In this case, we are extending the default templating syntax with a custom template command named “link”. The benefit of using data linking with the above template is that the SPAN elements will be automatically updated whenever the underlying “product” data is updated.  Declarative data linking also makes it easier to create edit and insert forms. For example, you could create a form for editing a product by using declarative data linking like this: Whenever you change the value of the INPUT elements in a template that uses declarative data linking, the underlying JavaScript data object is automatically updated. Instead of needing to write code to scrape the HTML form to get updated values, you can instead work with the underlying data directly – making your client-side code much cleaner and simpler. Downloading Working Code Examples of the Above Scenarios You can download this .zip file to get with working code examples of the above scenarios.  The .zip file includes 4 static HTML page: Listing1_Templating.htm – Illustrates basic templating. Listing2_TemplatingConditionals.htm – Illustrates templating with the use of the if and each template commands. Listing3_DataLinking.htm – Illustrates data linking. Listing4_Converters.htm – Illustrates using a converter with data linking. You can un-zip the file to the file-system and then run each page to see the concepts in action. Summary We are excited to be able to begin participating within the open-source jQuery project.  We’ve received lots of encouraging feedback in response to our first two proposals, and we will continue to actively contribute going forward.  These features will hopefully make it easier for all developers (including ASP.NET developers) to build great Ajax applications. Hope this helps, Scott P.S. [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu]

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• Parallelism in .NET – Part 12, More on Task Decomposition

  - by Reed

  Many tasks can be decomposed using a Data Decomposition approach, but often, this is not appropriate.  Frequently, decomposing the problem into distinctive tasks that must be performed is a more natural abstraction. However, as I mentioned in Part 1, Task Decomposition tends to be a bit more difficult than data decomposition, and can require a bit more effort.  Before we being parallelizing our algorithm based on the tasks being performed, we need to decompose our problem, and take special care of certain considerations such as ordering and grouping of tasks. Up to this point in this series, I’ve focused on parallelization techniques which are most appropriate when a problem space can be decomposed by data.  Using PLINQ and the Parallel class, I’ve shown how problem spaces where there is a collection of data, and each element needs to be processed, can potentially be parallelized. However, there are many other routines where this is not appropriate.  Often, instead of working on a collection of data, there is a single piece of data which must be processed using an algorithm or series of algorithms.  Here, there is no collection of data, but there may still be opportunities for parallelism. As I mentioned before, in cases like this, the approach is to look at your overall routine, and decompose your problem space based on tasks.  The idea here is to look for discrete “tasks,” individual pieces of work which can be conceptually thought of as a single operation. Let’s revisit the example I used in Part 1, an application startup path.  Say we want our program, at startup, to do a bunch of individual actions, or “tasks”.  The following is our list of duties we must perform right at startup: Display a splash screen Request a license from our license manager Check for an update to the software from our web server If an update is available, download it Setup our menu structure based on our current license Open and display our main, welcome Window Hide the splash screen The first step in Task Decomposition is breaking up the problem space into discrete tasks. This, naturally, can be abstracted as seven discrete tasks.  In the serial version of our program, if we were to diagram this, the general process would appear as: These tasks, obviously, provide some opportunities for parallelism.  Before we can parallelize this routine, we need to analyze these tasks, and find any dependencies between tasks.  In this case, our dependencies include: The splash screen must be displayed first, and as quickly as possible. We can’t download an update before we see whether one exists. Our menu structure depends on our license, so we must check for the license before setting up the menus. Since our welcome screen will notify the user of an update, we can’t show it until we’ve downloaded the update. Since our welcome screen includes menus that are customized based off the licensing, we can’t display it until we’ve received a license. We can’t hide the splash until our welcome screen is displayed. By listing our dependencies, we start to see the natural ordering that must occur for the tasks to be processed correctly. The second step in Task Decomposition is determining the dependencies between tasks, and ordering tasks based on their dependencies. Looking at these tasks, and looking at all the dependencies, we quickly see that even a simple decomposition such as this one can get quite complicated.  In order to simplify the problem of defining the dependencies, it’s often a useful practice to group our tasks into larger, discrete tasks.  The goal when grouping tasks is that you want to make each task “group” have as few dependencies as possible to other tasks or groups, and then work out the dependencies within that group.  Typically, this works best when any external dependency is based on the “last” task within the group when it’s ordered, although that is not a firm requirement.  This process is often called Grouping Tasks.  In our case, we can easily group together tasks, effectively turning this into four discrete task groups: 1. Show our splash screen – This needs to be left as its own task.  First, multiple things depend on this task, mainly because we want this to start before any other action, and start as quickly as possible. 2. Check for Update and Download the Update if it Exists - These two tasks logically group together.  We know we only download an update if the update exists, so that naturally follows.  This task has one dependency as an input, and other tasks only rely on the final task within this group. 3. Request a License, and then Setup the Menus – Here, we can group these two tasks together.  Although we mentioned that our welcome screen depends on the license returned, it also depends on setting up the menu, which is the final task here.  Setting up our menus cannot happen until after our license is requested.  By grouping these together, we further reduce our problem space. 4. Display welcome and hide splash - Finally, we can display our welcome window and hide our splash screen.  This task group depends on all three previous task groups – it cannot happen until all three of the previous groups have completed. By grouping the tasks together, we reduce our problem space, and can naturally see a pattern for how this process can be parallelized.  The diagram below shows one approach: The orange boxes show each task group, with each task represented within.  We can, now, effectively take these tasks, and run a large portion of this process in parallel, including the portions which may be the most time consuming.  We’ve now created two parallel paths which our process execution can follow, hopefully speeding up the application startup time dramatically. The main point to remember here is that, when decomposing your problem space by tasks, you need to: Define each discrete action as an individual Task Discover dependencies between your tasks Group tasks based on their dependencies Order the tasks and groups of tasks

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• CodePlex Daily Summary for Tuesday, March 09, 2010

  CodePlex Daily Summary for Tuesday, March 09, 2010New Projects.NET Excel Wrapper - Read, Write, Edit & Automate Excel Files in .NET with ease: .NET Excel Wrapper encapsulates the complexity of working with multiple Excel objects giving you one central point to do all your processing. It h...Advancement Voyage: Advancement Voyage is a high quality RPG experience that provides all the advancement and voyaging that a player could hope for.ASP.Net Routing configuration: ASP.NET routing configuration enables you to configure the routes in the web.config bbinjest: bbinjestBuildUp: BuildUp is a build number increment tool for C# .net projects. It is run as a post build step in Visual Studio.Controlled Vocabulary: This project is devoted to creating tools to assist with Controlling Vocabulary in communication. The initial delivery is an Outlook 2010 Add-in w...CycleList: A replacement for the WPF ListBox Control. Displays only a single item and allows the user to change the selected item by clicking on it once. Very...Forensic Suite: A suite of security softwareFREE DNN Chat Module for 123 Flash Chat -- Embed FREE Chat Room!: 123 Flash Chat is a live chat solution and its DotNetNuke Chat Module helps to embed a live chat room into website with DotNetNuke(DNN) integrated ...HouseFly experimental controls: Experimental controls for use in HouseFly.ICatalogAll: junkMidiStylus: MidiStylus allows you to control MIDI-enabled hardware or software using your pressure-sensitive pen tablet. The program maps the X position, Y po...myTunes: Search for your favorite artistsNColony - Pluggable Socialism?: NColony will maximize the use of MEF to create flexible application architectures through a suite of plug-in solutions. If MEF is an outlet for plu...Network Monitor Decryption Expert: NmDecrypt is a Network Monitor Expert which when given a trace with encrypted frames, a security certificate, and a passkey will create a new trace...occulo: occulo is a free steganography program, meant to embed files within images with optional encrytion. Open Ant: A implementation of a Open Source Ant which is created to show what is possible in the serious game AntMe! The First implementation of that ProjectProgramming Patterns by example: Design patterns provide solutions to common software design problems. This project will contain samples, written in c# and ruby, of each design pat...project4k: Developing bulk mail system storing email informationQuail - Selenium Remote Control Made Easy: Quail makes it easy for Quality Assurance departments write automated tests against web applications. Both HTML and Silverlight applications can b...RedBulb for XNA Framework: RedBulb is a collection of utility functions and classes that make writing games with XNA a lot easier. Key features: Console,GUI (Labels, Buttons,...RegExpress: RegExpress is a WPF application that combines interactive demos of regular expressions with slide content. This was designed for a user group prese...RemoveFolder: Small utility program to remove empty foldersScrumTFS: ScrumTFSSharePoint - Open internal link in new window list definition: A simple SharePoint list definition to render SharePoint internal links with the option to open them in a new window.SqlSiteMap4MVC: SqlSiteMapProvider for ASP.Net MVC.T Sina .NET Client: t.sina.com.cn api 新浪微博APITest-Lint-Extensions: Test Lint is a free Typemock VS 2010 Extension that finds common problems in your unit tests as you type them. this project will host extensions ...ThinkGearNET: ThinkGearNET is a library for easy usage of the Neurosky Mindset headset from .NET .Wiki to Maml: This project enables you to write wiki syntax and have it converted into MAML syntax for Sandcastle documentation projects.WPF Undo/Redo Framework: This project attempts to solve the age-old programmer problem of supporting unlimited undo/redo in an application, in an easily reusable manner. Th...WPFValidators: WPF Validators Validações de campos para WPFWSP Listener: The WSP listener is a windows service application which waits for new WSC and WSP files in a specific folder. If a new WSC and WSP file are added, ...New Releases.NET Excel Wrapper - Read, Write, Edit & Automate Excel Files in .NET with ease: First Release: This is the first release which includes the main library release..NET Excel Wrapper - Read, Write, Edit & Automate Excel Files in .NET with ease: Updated Version: New Features:SetRangeValue using multidimensional array Print current worksheet Print all worksheets Format ranges background, color, alig...ArkSwitch: ArkSwitch v1.1.2: This release removes all memory reporting information, and is focused on stability.BattLineSvc: V2.1: - Fixed a bug where on system start-up, it would pop up a notification box to let you know the service started. Annoying! And fixed! - Fixed the ...BuildUp: BuildUp 1.0 Alpha 1: Use at your own risk!Not yet feature complete. Basic build incrementing and attribute overriding works. Still working on cascading build incremen...Controlled Vocabulary: 1.0.0.1: Initial Alpha Release. System Requirements Outlook 2010 .Net Framework 3.5 Installation 1. Close Outlook (Use Task Manager to ensure no running i...CycleList: CycleList: The binaries contain the .NET 3.5 DLL ONLY. Please download source for usage examples.FluentNHibernate.Search: 0.3 Beta: 0.3 Beta take the following changes : Mappings : - Field Mapping without specifying "Name" - Id Mapping without specifiying "Field" - Builtin Anal...FREE DNN Chat Module for 123 Flash Chat -- Embed FREE Chat Room!: 123 Flash Chat DNN Chat Module: With FREE DotNetNuke Chat Module of 123 Flash Chat, webmaster will be assist to add a chat room into DotNetNuke instantly and help to attract more ...GameStore League Manager: League Manager 1.0 release 3: This release includes a full installer so that you can get your league running faster and generate interest quicker.iExporter - iTunes playlist exporting: iExporter gui v2.3.1.0 - console v1.2.1.0: Paypal donate! Solved a big bug for iExporter ( Gui & Console ) When a track isn't located under the main iTunes library, iExporter would crash! ...jQuery.cssLess: jQuery.cssLess 0.3: New - Removed the dependency from XRegExp - Added comment support (both CSS style and C style) - Optimised it for speed - Added speed test TOD...jQuery.cssLess: jQuery.cssLess 0.4: NEW - @import directive - preserving of comments in the resulting CSS - code refactoring - more class oriented approach TODO - implement operation...MapWindow GIS: MapWindow 6.0 msi (March 8): Rewrote the shapefile saving code in the indexed case so that it uses the shape indices rather than trying to create features. This should allow s...MidiStylus: MidiStylus 0.5.1: MidiStylus Beta 0.5.1 This release contains basic functionality for transmitting MIDI data based on X position, Y position, and pressure value rea...MiniTwitter: 1.09.1: MiniTwitter 1.09.1 更新内容 修正 URL に & が含まれている時に短縮 URL がおかしくなるバグを修正Mosaictor: first executable: .exe file of the app in its current state. Mind you that this will likely be highly unstable due to heaps of uncaught errors.MvcContrib a Codeplex Foundation project: T4MVC: T4MVC is a T4 template that generates strongly typed helpers for ASP.NET MVC. 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It will be a PowerShell 2 host, without support for PowerShell 1.0 I have used some of the new P...Quick Performance Monitor: QPerfmon 1.1: Now you can specify different updating frequencies.RedBulb for XNA Framework: Cipher Puzzle (Sample) Creators Club Package: RedBulb Sample Game: Cipher Puzzle http://bayimg.com/image/galgfaacb.jpgRedBulb for XNA Framework: RedBulbStarter (Base Code): This is the code you need to start with. Quick Start Guide: Download the latest version of RedBulb: http://redbulb.codeplex.com/releases/view/415...RoTwee: RoTwee 7.0.0.0 (Alpha): Now this version is under improvement of code structure and may be buggy. However movement of rotation is quite good in this version thanks to clea...SCSI Interface for Multimedia and Block Devices: Release 9 - Improvements and Bug Fixes: Changes I have made in this version: Fixed INQUIRY command timeout problem Lowered ISOBurn's memory usage significantly by not explicitly setting...SharePoint - Open internal link in new window list definition: Open link in new window list definition: First release, with english and italian localization supportSharePoint Outlook Connector: Version 1.2.3.2: Few bug fixing and some ui enhancementsSysI: sysi, release build: Better than ever -- now allows for escalation to adminThe Silverlight Hyper Video Player [http://slhvp.com]: Beta 1: Beta (1.1) The code is ready for intensive testing. 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• A Taxonomy of Numerical Methods v1

  - by JoshReuben

  Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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• CodePlex Daily Summary for Monday, April 12, 2010

  CodePlex Daily Summary for Monday, April 12, 2010New Projects3 Hour Game Design Contest: The 3 Hour Game Design Contest is a programming contest for making simple games in 3 hours. 3 hours may not seem like enough time to make a game, b...BI Monkey SSIS ETL Framework: The BI Monkey SSIS ETL Framework is an ETL Execution, Control and Logging system for ETL projects using SSIS. It is supported by a SQL Server metad...Blend Sample Data Helpers: Helper behavior classes to generate sample images and data from Internet sources such as Flickr images. Bold TCP for Delphi 7: Open Sourcing the Bold TCP for Delphi 7.cfThreadingTools: This library project contains classes and extensions which will allow easy handling of multi-threaded UI-accesses.CuBiX_SDL: CuBiX_SDL : CuBiX est un projet personnel.Draglets: Draglets makes it easier for editors and CMS-developers to move and reorder content at their web sites. It's developed in ASP.NET, C# with WCF and ...DSQLT - Dynamic SQL Templates: DSQLT - Dynamic SQL Templates Use Stored Procedures as templates for dynamic SQL statements. Substitute parameters @0-@9 with values like objectna...Edtter: Edtter is a sample web application built on ASP.NET MVC 2 Framework. (Japanese Version Only)Forms Based Authentication Management - SharePoint2007FBA: This is my own update to Stacy Draper's FBABasic project for Forms Based Authentication in MOSS 2007. In additon to managing your fba user's roles,...Height Map to 3D World at XNA: Height Map to 3D World is a XNA project that developed firstly by Eric Grossinger and secondly improved by Karadeniz Technical University Computer ...HouseFly: A simple contact and note taking applicationITM 495 - iPhone Web App: School ProjectKaufleute: This will be finished laterLR: this project is about connecting toPowerShell Integration Services: A set of tools aimed at Extract Transform and Load tasks. Focused on getting the most common ETL tasks done without SSIS. Salient: A collection of, hopefully, useful libraries.Samurai.Validation: Extensible and flexible .Net object validation frameworkSamurai.Workflow: Samurai Workflow is a slim, easy-to-use workflow framework for WPF applications.SharePoint User Management WebPart: SharePoint User Management WebPartUrl shorte(ne)r: It's simple Url Shortener (like: http://tinyurl.com) Currently only Polish language is supported. In future will be provided multi language suppor...Yasbg: Yasbg (pronounced yas-bug) is Yet Another Static Blog Generator. It is made in C# using MarkdownSharp for markdown. Currently in alpha. New Releases.NET Extensions - Extension Methods Library: Release 2010.06: Added an universal approach for grouping extension methods like conversions. Conversion are now available on any data type (it's actually extension...3 Hour Game Design Contest: 3H-GDC mVII: This is the collection of game files for the 7th 3H-GDCB&W Port Scanner: Black`n`White Port Scanner 3.0: B&W Port Scanner 3 includes FTP Server detection tool, Better stability, Optimized memory management, Saving & Opening Result sets ... and more new...BI Monkey SSIS ETL Framework: Framework v1 Alpha: This Alpha release is not fully tested and some functionality is not operating as intended.Bluetooth Radar: Version 1.7: UI Changes Device UserControl Randomly placed devices.BugTracker.NET: BugTracker.NET 3.4.1: For the tasks/time tracking feature, added a way of viewing all the tasks at once, not just the tasks for one bug. Also added a way of exporting a...cfThreadingTools: cfThreadingTools 0.1.1.8: This is the first public available release. Following items are included: BaseTools-class which allows thread-safe setting of properties and callin...DeepZoom Pivot Constructor: DeepZoom Pivot Constructor v0.1: This is a test release of the library platform - Targets .NET 3.5 No samples yet, etc., but it works well :-)DSQLT - Dynamic SQL Templates: Initial release with License Included: nothing changed but license print procedure included the zip file contains database backup SQL script readmeForms Based Authentication Management - SharePoint2007FBA: SharePoint2007FBA 1.0.0.0: Downloads for the Project solution and the WSP package. Please read the Setup Guide. If you are unfamiliar with setting up Forms Based Authenticati...Foursquare BlogEngine Widget: foursquare widget for BlogEngine.NET version 0.3: To see the changes which have been made, visit http://philippkueng.ch/post/Foursquare-BlogEngineNET-widget-version-03.aspx For installation instruc...Framework Detector: FrameworkDetect Support .NET 4 v2: FrameworkDetect Support .NET 4Happy Turtle Plugins for BVI :: Repository Based Versioning for Visual Studio: Happy Turtle 1.0.46860: This is the second beta release of the SVN based version incrementor. Please feel free to create a thread in the discussion tabs and provide feedb...Height Map to 3D World at XNA: 3DWorld: Just open .rar file and extract it any folder and run Proje2Dto3D.exe file.HTML Ruby: 6.20.2: Removed rubyLineSpace option Improved options panel Fixed ruby text font-size rendering issue with complex ruby annotation Removed more waste...HTML Ruby: 6.20.3: Removed unused code Temporary partial fix for Firefox 3.7a4pre nightly buildHTML Ruby: 6.21.0: Added support for current HTML5 ruby annotation format. All ruby annotations are converted to XHTML 1.1 complex ruby annotation.Kooboo HTML form: Kooboo HTML Form Module for 2.1.0.0: Compatible with Kooboo cms 2.1.0.0 Upgrade to MVC 2Kooboo Menu: Kooboo CMS Menu for 2.1.0.0: Compatible with Kooboo cms 2.1.0.0 Upgrade to MVC 2Kooboo Meta: Kooboo Meta Module for 2.1.0.0: Compatible with Kooboo cms 2.1.0.0 Upgrade to MVC 2Kooboo PageMenu: Kooboo CMS PageMenu for 2.1.0.0: Compatible with Kooboo cms 2.1.0.0 Upgrade to MVC 2Kooboo Search: Kooboo CMS Search module for 2.1.0.0: Compatible with Kooboo cms 2.1.0.0 Upgrade to MVC 2Numina Application/Security Framework: Numina.Framework Core 50212: Added bulk import user page Added General settings page for updating Company Name, Theme, and API Key Add/Edit application calls Full URL to h...Rawr: Rawr 2.3.14: - Rawr3: Tons of fixes for Rawr3 compatability and UI. - Significant performance improvements all around. - More fixes and improvements to Wowhea...Rich Ajax empowered Web/Cloud Applications: 6.4 beta 2: The first fully featured version of Visual webGui offering web/cloud development tool that puts all ASP.NET Ajax limits behind with enhanced perfor...SharePoint User Management WebPart: User Management Web part 1.0: Most of the organization have one SharePoint Site which is configured with windows authenticated which is for internal employees having AD authenti...SkeinLibManaged: SkeinLibManaged 1.1.0.0 (Beta): This is the compiled DLL with XML documentation, so there should be plenty of context sensitive help and Intellisense. This is the Release version,...VCC: Latest build, v2.1.30411.0: Automatic drop of latest buildVFPX: Code References 1.1 Beta: Visit the Code References Info Page for complete information about this release.VisioAutomation: VisioAutomation 2.5.0: VisioAutomation 2.5.0- General cleanup/bugfixes - Many low-level changes the the VisioAutomation extension methods - these are far fewer now - This...Visual Studio DSite: English To Spanish Translator (Visual C++ 2008): A simple english to spanish translator made in visual c 2008, using the Google Translate API.WatchersNET CKEditor™ Provider for DotNetNuke: CKEditor Provider 1.10.00: Whats NewFile Browser: Inherits Folder Permissions from DotNetNuke Updated the Editor to Version 3.2.1 revision 5372 Added CkEditor jQuery Adap...Web/Cloud Applications Development Framework | Visual WebGui: 6.4 beta 2: The first fully featured version of Visual webGui offering web/cloud development tool that puts all ASP.NET Ajax limits behind with unique develope...WPF Data Virtualization: 1.0.0.0: First ReleaseYasbg: Yasbg Alpha: ReadmeYet Another Static Blog Generator is a command line utility that generates static html files for blogs. Currently, it is NOT feed enabled. I...異世界の新着動画: Ver. 10-04-12: ニコ生の仕様変更に対応 アンケート時間の設定追加Most Popular ProjectsWBFS ManagerRawrASP.NET Ajax LibraryMicrosoft SQL Server Product Samples: DatabaseAJAX Control ToolkitSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesFacebook Developer ToolkitMost Active ProjectsRawrnopCommerce. Open Source online shop e-commerce solution.AutoPocopatterns & practices – Enterprise LibraryShweet: SharePoint 2010 Team Messaging built with PexFarseer Physics EngineNB_Store - Free DotNetNuke Ecommerce Catalog ModuleIonics Isapi Rewrite FilterBlogEngine.NETBeanProxy

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• Letter to Ballmer: Making Better Consumer Devices

  - by andrewbrust

  Last year, I wrote Steve Ballmer an email, and he was kind enough to write me back.  The email contained a scan of a column I wrote praising Microsoft’s BI strategy.  His reply contained three simple words: “Super nice  thanks.” Well, now I’d like to write to Steve again, in an open letter format, and this time the love may be a bit tougher.  But I’m still super earnest. The past two days have been eventful ones for Microsoft: The company announced the departure of company veterans Robbie Bach and J Allard and the market announced Apple is now besting Microsoft in market capitalization. Plus, announcements were made that make it plain that Ballmer will, in effect, be running Microsoft’s Entertainment & Devices division himself. With that in mind, I’d like to offer my list of a dozen things I think Microsoft’s CEO should do to improve that division’s offerings and, hopefully, its bottom line. So here goes:   1. On Windows Phone 7, Stay the Course The press is teeming with headlines and reader comments proclaiming the death-before-arrival of Windows Phone 7.  That’s plain silly.  You’ve got the makings of a great and unique SmartPhone platform, and you’re the only company (even considering RIM) that can offer full fidelity Exchange integration, not to mention implementing Office on the device.  Let the existing team finish this puppy and ship it. And then have them pump out a few updates, over-the-air, quickly.  Show them that Google Android’s not the only product that can do good, rapid dot releases. And another thing: make sure your OEMs’ devices have flawless touch screens.  If they don’t, then you shouldn’t certify them for delivery to customers.  Period. Oh, and kill the Kin, quietly.  It was DOA, and you know it.   2. Move Media Center to the Xbox Platform Media Center is, at its core, a good product.  But delivering a media distribution and DVR platform on a sophisticated PC operating system like Windows 7 just creates too many moving parts.  Xbox already functions as the best Media Center extender device – it should actually be the hub as well. Media Center is mostly based on .NET code – and XNA is a .NET environment for Xbox – find a way to bridge that small gap and make Media Center a joy to work with instead of a frustration.  Beating Apple TV out of this sub-market is the lowest hanging fruit on the tree (goofy pun, but it’s true).   3. Integrate Media Center with Mediaroom, or Kill the Latter You have two media products with almost identical names.  One is for standalone DVRs and the other is for IPTV cable set tops with DVR capabilities.  Can we merge these please?  My previous request of putting Media Center on Xbox would seem to tie into this nicely, since you’ve announced plans to do that with Mediaroom already.   4. Fix the Red Ring of Death People love the Xbox, but they really don’t love sending their consoles back every 18-24 months, when they get a bunch of red lights flashing on power up.  You’ve handled this defect about as gracefully as possible, but it’s been around for a long time now and it doesn’t seem to be fixed yet.  You can do better.  In fact, you must do better, or you insult your customers.   5. Add Blu Ray to Xbox I know, streaming movies are the future; physical media is legacy technology.  So if that’s true, why did you back HD DVD so hard?  You know why: for now, the film studios won’t allow a large selection of new release, HD, surround sound content be distributed on any medium other than Blu Ray or cable pay per view/on-demand.  Don’t you want home theater buffs to see the Xbox as a fantastic device for their rigs?  Don’t you want to put PlayStation 3 out of its misery?  And if you follow my suggestions above (move Media Center to the Xbox and fix the Red Ring problem), you’d have it all sewn up.  Do I think Blu Ray functionality will move a lot of units?  No.  Do I think that it would move more units with desperately needed influential home theater consumers?  You bet.  And you might sell more ZunePass subscriptions in the process. But while you’re at it, make the fan quieter, please.   6. Make More of Windows Home Server Home Server is a fantastic product.  And for reasons unknown to me, it seems like you’re letting it languish.  Development of the add-in ecosystem seems underfunded.  WHS’ unparalleled ease of use and reliability for home PC backup (and emergency restores) goes unsung.  Product cycles are slow.  Support for your OEMs, who are doing great work, especially in the green space with Atom CPUs, seems lacking.  You’ve married a trophy girl and you keep her cloistered at home!  That’s cruel, unusual and, um, incredibly ill-advised.  Make use of this ace card, and while you’re at it, give it real integration with Media Center.  The integration thus far proof-of-concept quality.  You should go way past that – both products will benefit immeasurably.   7. Set Up a Partner Platform for Custom Installers There’s a whole sub-industry of companies that install, integrate and configure home theater, security and connected home products.  They have an industry group. They are influential in the high-end of the consumer electronics industry, and so are their customers.  They love Media Center and they love Windows Home Server.  But I have talked to several of them at the Consumer Electronics Show and they tell me you don’t love them.  They find it very difficult to do business with Microsoft, even though they want nothing more than to sell and evangelize your platform.  This is a travesty.  Please fix it.  Get Allison Watson and the Microsoft Partner Network on board and have her hire someone who knows how to run a channel program for consumer electronics companies.  Problem solved.  Markets expanded.   8. Make Your Own Hardware In other areas, I know you love your partners.  I help run one, so I appreciate that.  But when it came to Xbox and Zune you built them it yourself (albeit on a contract basis, which is fine).  Windows Phone 7 has a chance to work as an OEM play, but it would work better if you produced the devices.  At least consider building a reference device that sells alongside your OEMs’ offerings.  That’s what Google did with the Nexxus One.  And while that phone was not itself a big seller, it catalyzed two wonderful things : (1) a quality bar was set and (2) partners exceeded it.  Before the Nexxus One, the best Android handset out there was the Motorola Droid. The Nexxus One was better, and the HTC Droid Incredible and Evo 4G are now even better than Google’s phone, which is why Verizon and Sprint decided not to carry it.  Imagine if all Windows Phone 6.x devices were on par with the HTC HD2.  I tend to believe you’d have a lot bigger market share than you do now.   9. Continue with Your Retail Initiative From what I hear, it sounds like it’s going well.  And this goes right along with making your own hardware.  When you build it, they will come.  And then it makes the likes of Best Buy and Staples do better.   10. Make an Acquisition (or Two) TiVo and/or Moxi look ripe for the picking.  With their ability to build stuff people love and your ability to run a business, you might just have something.  But do a better job than you did when you bought Danger.  Buy the ideas, not just the customers, eh?   11. Make Beautiful Stuff You’ve heard this one before, I know.  But I have some head-shrinking advice on this one.  You know that Apple obsesses over its industrial design.  You know that appeals to consumers.  But it seems you think doing so is Apple’s game exclusively and so you shouldn’t even try.  Bull dinky.  Come to New York and visit the Museum of Modern Art’s Architecture and Design gallery.  You’ll see that lots of companies and product categories have had very high design value well before Apple existed.  You can do this, and the Zune HD was a great start.  Now run with that.  Find those negative voices in your head that are telling you that you can’t and shut them up.  For good.   12. Burst the Bubble Some of the products you’ve built seem like they were conceived in a bizarro world.  That would appear to be the result of groupthink.  You must do better.  And there’s lots of people willing to advise you.  This includes just about everyone in the Regional Director program, and probably a bunch of MVPs.  Heck, I bet the guys at Engadget could help out too.  Imagine if you let them see the Kin before it shipped.  Talk to high-end gear consumers.  Talk to Best Buy and CostCo customers too.   Signing Off I hope this was of value to you.  As I wrote this I kept telling myself how obvious, even trite, some of these pieces of advice were and then, because of that, doubting they’d really help.  But I decided that they must not be obvious to Microsoft.  Sometimes when you get wrapped up in stuff, it’s hard to clear your head.  I think my head’s pretty clear here though (I’m wrapped up in other stuff), so maybe my perspective can help.  If not, well, then, I guess they all can’t be super nice.

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• Adventures in MVVM &ndash; My ViewModel Base

  - by Brian Genisio's House Of Bilz

  More Adventures in MVVM First, I’d like to say: THIS IS NOT A NEW MVVM FRAMEWORK. I tend to believe that MVVM support code should be specific to the system you are building and the developers working on it.  I have yet to find an MVVM framework that does everything I want it to without doing too much.  Don’t get me wrong… there are some good frameworks out there.  I just like to pick and choose things that make sense for me.  I’d also like to add that some of these features only work in WPF.  As of Silveright 4, they don’t support binding to dynamic properties, so some of the capabilities are lost. That being said, I want to share my ViewModel base class with the world.  I have had several conversations with people about the problems I have solved using this ViewModel base.  A while back, I posted an article about some experiments with a “Rails Inspired ViewModel”.  What followed from those ideas was a ViewModel base class that I take with me and use in my projects.  It has a lot of features, all designed to reduce the friction in writing view models. I have put the code out on Codeplex under the project: ViewModelSupport. Finally, this article focuses on the ViewModel and only glosses over the View and the Model.  Without all three, you don’t have MVVM.  But this base class is for the ViewModel, so that is what I am focusing on. Features: Automatic Command Plumbing Property Change Notification Strongly Typed Property Getter/Setters Dynamic Properties Default Property values Derived Properties Automatic Method Execution Command CanExecute Change Notification Design-Time Detection What about Silverlight? Automatic Command Plumbing This feature takes the plumbing out of creating commands.  The common pattern for commands in a ViewModel is to have an Execute method as well as an optional CanExecute method.  To plumb that together, you create an ICommand Property, and set it in the constructor like so: Before public class AutomaticCommandViewModel { public AutomaticCommandViewModel() { MyCommand = new DelegateCommand(Execute_MyCommand, CanExecute_MyCommand); } public void Execute_MyCommand() { // Do something } public bool CanExecute_MyCommand() { // Are we in a state to do something? return true; } public DelegateCommand MyCommand { get; private set; } } With the base class, this plumbing is automatic and the property (MyCommand of type ICommand) is created for you.  The base class uses the convention that methods be prefixed with Execute_ and CanExecute_ in order to be plumbed into commands with the property name after the prefix.  You are left to be expressive with your behavior without the plumbing.  If you are wondering how CanExecuteChanged is raised, see the later section “Command CanExecute Change Notification”. After public class AutomaticCommandViewModel : ViewModelBase { public void Execute_MyCommand() { // Do something } public bool CanExecute_MyCommand() { // Are we in a state to do something? return true; } }   Property Change Notification One thing that always kills me when implementing ViewModels is how to make properties that notify when they change (via the INotifyPropertyChanged interface).  There have been many attempts to make this more automatic.  My base class includes one option.  There are others, but I feel like this works best for me. The common pattern (without my base class) is to create a private backing store for the variable and specify a getter that returns the private field.  The setter will set the private field and fire an event that notifies the change, only if the value has changed. Before public class PropertyHelpersViewModel : INotifyPropertyChanged { private string text; public string Text { get { return text; } set { if(text != value) { text = value; RaisePropertyChanged("Text"); } } } protected void RaisePropertyChanged(string propertyName) { var handlers = PropertyChanged; if(handlers != null) handlers(this, new PropertyChangedEventArgs(propertyName)); } public event PropertyChangedEventHandler PropertyChanged; } This way of defining properties is error-prone and tedious.  Too much plumbing.  My base class eliminates much of that plumbing with the same functionality: After public class PropertyHelpersViewModel : ViewModelBase { public string Text { get { return Get<string>("Text"); } set { Set("Text", value);} } }   Strongly Typed Property Getters/Setters It turns out that we can do better than that.  We are using a strongly typed language where the use of “Magic Strings” is often frowned upon.  Lets make the names in the getters and setters strongly typed: A refinement public class PropertyHelpersViewModel : ViewModelBase { public string Text { get { return Get(() => Text); } set { Set(() => Text, value); } } }   Dynamic Properties In C# 4.0, we have the ability to program statically OR dynamically.  This base class lets us leverage the powerful dynamic capabilities in our ecosystem. (This is how the automatic commands are implemented, BTW)  By calling Set(“Foo”, 1), you have now created a dynamic property called Foo.  It can be bound against like any static property.  The opportunities are endless.  One great way to exploit this behavior is if you have a customizable view engine with templates that bind to properties defined by the user.  The base class just needs to create the dynamic properties at runtime from information in the model, and the custom template can bind even though the static properties do not exist. All dynamic properties still benefit from the notifiable capabilities that static properties do. For any nay-sayers out there that don’t like using the dynamic features of C#, just remember this: the act of binding the View to a ViewModel is dynamic already.  Why not exploit it?  Get over it :) Just declare the property dynamically public class DynamicPropertyViewModel : ViewModelBase { public DynamicPropertyViewModel() { Set("Foo", "Bar"); } } Then reference it normally <TextBlock Text="{Binding Foo}" />   Default Property Values The Get() method also allows for default properties to be set.  Don’t set them in the constructor.  Set them in the property and keep the related code together: public string Text { get { return Get(() => Text, "This is the default value"); } set { Set(() => Text, value);} }   Derived Properties This is something I blogged about a while back in more detail.  This feature came from the chaining of property notifications when one property affects the results of another, like this: Before public class DependantPropertiesViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); RaisePropertyChanged("Percentage"); RaisePropertyChanged("Output"); } } public int Percentage { get { return (int)(100 * Score); } } public string Output { get { return "You scored " + Percentage + "%."; } } } The problem is: The setter for Score has to be responsible for notifying the world that Percentage and Output have also changed.  This, to me, is backwards.    It certainly violates the “Single Responsibility Principle.” I have been bitten in the rear more than once by problems created from code like this.  What we really want to do is invert the dependency.  Let the Percentage property declare that it changes when the Score Property changes. After public class DependantPropertiesViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); } } [DependsUpon("Score")] public int Percentage { get { return (int)(100 * Score); } } [DependsUpon("Percentage")] public string Output { get { return "You scored " + Percentage + "%."; } } }   Automatic Method Execution This one is extremely similar to the previous, but it deals with method execution as opposed to property.  When you want to execute a method triggered by property changes, let the method declare the dependency instead of the other way around. Before public class DependantMethodsViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); WhenScoreChanges(); } } public void WhenScoreChanges() { // Handle this case } } After public class DependantMethodsViewModel : ViewModelBase { public double Score { get { return Get(() => Score); } set { Set(() => Score, value); } } [DependsUpon("Score")] public void WhenScoreChanges() { // Handle this case } }   Command CanExecute Change Notification Back to Commands.  One of the responsibilities of commands that implement ICommand – it must fire an event declaring that CanExecute() needs to be re-evaluated.  I wanted to wait until we got past a few concepts before explaining this behavior.  You can use the same mechanism here to fire off the change.  In the CanExecute_ method, declare the property that it depends upon.  When that property changes, the command will fire a CanExecuteChanged event, telling the View to re-evaluate the state of the command.  The View will make appropriate adjustments, like disabling the button. DependsUpon works on CanExecute methods as well public class CanExecuteViewModel : ViewModelBase { public void Execute_MakeLower() { Output = Input.ToLower(); } [DependsUpon("Input")] public bool CanExecute_MakeLower() { return !string.IsNullOrWhiteSpace(Input); } public string Input { get { return Get(() => Input); } set { Set(() => Input, value);} } public string Output { get { return Get(() => Output); } set { Set(() => Output, value); } } }   Design-Time Detection If you want to add design-time data to your ViewModel, the base class has a property that lets you ask if you are in the designer.  You can then set some default values that let your designer see what things might look like in runtime. Use the IsInDesignMode property public DependantPropertiesViewModel() { if(IsInDesignMode) { Score = .5; } }   What About Silverlight? Some of the features in this base class only work in WPF.  As of version 4, Silverlight does not support binding to dynamic properties.  This, in my opinion, is a HUGE limitation.  Not only does it keep you from using many of the features in this ViewModel, it also keeps you from binding to ViewModels designed in IronRuby.  Does this mean that the base class will not work in Silverlight?  No.  Many of the features outlined in this article WILL work.  All of the property abstractions are functional, as long as you refer to them statically in the View.  This, of course, means that the automatic command hook-up doesn’t work in Silverlight.  You need to plumb it to a static property in order for the Silverlight View to bind to it.  Can I has a dynamic property in SL5?     Good to go? So, that concludes the feature explanation of my ViewModel base class.  Feel free to take it, fork it, whatever.  It is hosted on CodePlex.  When I find other useful additions, I will add them to the public repository.  I use this base class every day.  It is mature, and well tested.  If, however, you find any problems with it, please let me know!  Also, feel free to suggest patches to me via the CodePlex site.  :)

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• CodePlex Daily Summary for Sunday, March 07, 2010

  CodePlex Daily Summary for Sunday, March 07, 2010New ProjectsAlgorithminator: Universal .NET algorithm visualizer, which helps you to illustrate any algorithm, written in any .NET language. Still in development.ALToolkit: Contains a set of handy .NET components/classes. Currently it contains: * A Numeric Text Box (an Extended NumericUpDown) * A Splash Screen base fo...Automaton Home: Automaton is a home automation software built with a n-Tier, MVVM pattern utilzing WCF, EF, WPF, Silverlight and XBAP.Developer Controls: Developer Controls contains various controls to help build applications that can script/write code.Dynamic Reference Manager: Dynamic Reference Manager is a set (more like a small group) of classes and attributes written in C# that allows any .NET program to reference othe...indiologic: Utilities of an IndioNeural Cryptography in F#: This project is my magistracy resulting work. It is intended to be an example of using neural networks in cryptography. Hashing functions are chose...Particle Filter Visualization: Particle Filter Visualization Program for the Intel Science and Engineering FairPólya: Efficient, immutable, polymorphic collections. .Net lacks them, we provide them*. * By we, we mean I; and by efficient, I mean hopefully so.project euler solutions from mhinze: mhinze project euler solutionsSilverlight 4 and WCF multi layer: Silverlight 4 and WCF multi layersqwarea: Project for a browser-based, minimalistic, massively multiplayer strategy game. Part of the "Génie logiciel et Cloud Computing" course of the ENS (...SuperSocket: SuperSocket, a socket application framework can build FTP/SMTP/POP server easilyToast (for ASP.NET MVC): Dynamic, developer & designer friendly content injection, compression and optimization for ASP.NET MVCNew ReleasesALToolkit: ALToolkit 1.0: Binary release of the libraries containing: NumericTextBox SplashScreen Based on the VB.NET code, but that doesn't really matter.Blacklist of Providers: 1.0-Milestone 1: Blacklist of Providers.Milestone 1In this development release implemented - Main interface (Work Item #5453) - Database (Work Item #5523)C# Linear Hash Table: Linear Hash Table b2: Now includes a default constructor, and will throw an exception if capacity is not set to a power of 2 or loadToMaintain is below 1.Composure: CassiniDev-Trunk-40745-VS2010.rc1.NET4: A simple port of the CassiniDev portable web server project for Visual Studio 2010 RC1 built against .NET 4.0. The WCF tests currently fail unless...Developer Controls: DevControls: These are the version 1.0 releases of these controls. Download the individually or all together (in a .zip file). More releases coming soon!Dynamic Reference Manager: DRM Alpha1: This is the first release. I'm calling it Alpha because I intend implementing other functions, but I do not intend changing the way current functio...ESB Toolkit Extensions: Tellago SOA ESB Extenstions v0.3: Windows Installer file that installs Library on a BizTalk ESB 2.0 system. This Install automatically configures the esb.config to use the new compo...GKO Libraries: GKO Libraries 0.1 Alpha: 0.1 AlphaHome Access Plus+: v3.0.3.0: Version 3.0.3.0 Release Change Log: Added Announcement Box Removed script files that aren't needed Fixed & issue in directory path Stylesheet...Icarus Scene Engine: Icarus Scene Engine 1.10.306.840: Icarus Professional, Icarus Player, the supporting software for Icarus Scene Engine, with some included samples, and the start of a tutorial (with ...mavjuz WndLpt: wndlpt-0.2.5: New: Response to 5 LPT inputs "test i 1" New: Reaction to 12 LPT outputs "test q 8" New: Reaction to all LPT pins "test pin 15" New: Syntax: ...Neural Cryptography in F#: Neural Cryptography 0.0.1: The most simple version of this project. It has a neural network that works just like logical AND and a possibility to recreate neural network from...Password Provider: 1.0.3: This release fixes a bug which caused the program to crash when double clicking on a generic item.RoTwee: RoTwee 6.2.0.0: New feature is as next. 16649 Add hashtag for tweet of tune.Now you can tweet your playing tune with hashtag.Visual Studio DSite: Picture Viewer (Visual C++ 2008): This example source code allows you to view any picture you want in the click of a button. All you got to do is click the button and browser via th...WatchersNET CKEditor™ Provider for DotNetNuke: CKEditor Provider 1.8.00: Whats New File Browser: Folders & Files View reworked File Browser: Folders & Files View reworked File Browser: Folders are displayed as TreeVi...WSDLGenerator: WSDLGenerator 0.0.0.4: - replaced CommonLibrary.dll by CommandLineParser.dll - added better support for custom complex typesMost Popular ProjectsMetaSharpSilverlight ToolkitASP.NET Ajax LibraryAll-In-One Code FrameworkWindows 7 USB/DVD Download Toolニコ生アラートWindows Double ExplorerVirtual Router - Wifi Hot Spot for Windows 7 / 2008 R2Caliburn: An Application Framework for WPF and SilverlightArkSwitchMost Active ProjectsUmbraco CMSRawrSDS: Scientific DataSet library and toolsBlogEngine.NETjQuery Library for SharePoint Web Servicespatterns & practices – Enterprise LibraryIonics Isapi Rewrite FilterFarseer Physics EngineFasterflect - A Fast and Simple Reflection APIFluent Assertions

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• CodePlex Daily Summary for Wednesday, March 10, 2010

  CodePlex Daily Summary for Wednesday, March 10, 2010New ProjectsASP.NET jQuery MessageBox: The ASP.NET jQuery it's an Web User Control that uses jQuery framework to enable diferent ways to present information to the user, by using these ...CommentRemover: Utility for removing comments from source codes. Support PL/SQL, Delphi, C/C#/C++ Developed in C# Requirement Microsoft .NET Framework 3.5DotNetNuke® RadMenu: DNNRadMenu makes it easy to create skins which use telerik RadMenu functionality. Licensing permits anyone (including designers) to use the compon...DotNetNuke® Skin AlphaBrisk: A DotNetNuke Design Challenge skin package submitted to the "Web Standards" category by dnnskin.net. Eight themes using transparent png, div, CSS, ...DotNetNuke® Skin Collaborate: A DotNetNuke Design Challenge skin package submitted to the "Modern Business" category by Cuong Dang of R2Integrated. This package is 100% XHTML an...DotNetNuke® Skin TR: A DotNetNuke Design Challenge skin package submitted to the "Out of the box" category by Tracy Wittenkeller of T-Worx. This package is 100% XHTML, ...Encrypted Notes: Encrypted Notes is similar to Notes, but uses Triple DES to encrypt text and files. It has a random key generator, and can save the key. It is deve...FalconLobby: FalconLobby is an authorized AddOn for Falcon 4.0 Allied Force which was created to support the multiplayer experience. FalconLobby retrieves the l...INETA Europe WebSite: Website for INETA EuropeInsert a Favorite (Bookmark) plugin for Windows Live Writer: This Windows Live Writer plugin allows you to select a Favorite (Bookmark) and insert it into your blog entry.Javascript Lib: an javascript libraryjqGrid ASP.Net MVC Control: A fully integrated ASP.Net MVC (2.0) grid control based on the successfull jqGrid plugin for the jQuery jscript framework. Among the features of...Mosaictor: Mosaictor is a per project of mine that I started halfway my education. It is a photo mosaic creator using locally saved files and files obtained t...Notes: Notes is a simple but fast text editor. It can save in many text formats, and includes many features, such as templates (soon to be customizable), ...notmuchweb: A web frontend for notmuchPervasiveID: The PID is actively involved in Open Source ID community-building and education. 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Without them, some of the properties in the designer ...CommonLibrary.NET: CommonLibrary.NET 0.9.4 - Beta 2: A collection of very reusable code and components in C# 3.5 ranging from ActiveRecord, Csv, Command Line Parsing, Configuration, Holiday Calendars,...Encrypted Notes: Source Code: This has the all the code for Encrypted Notes in a Text file.Hybrid Windows Service: Release Assembly: Main Assembly. Usage: 1. Add reference to this dll in your 'Windows Service' project. 2. Replace references to ServiceBase to HybridServiceBase in...jqGrid ASP.Net MVC Control: Version 1.0.0.0: Initial Versionkdar: KDAR 0.0.16: KDAR - Kernel Debugger Anti Rootkit - KINTERRUPT object check added - load image notifier check addedlatex2mathml: 1.0 alpha: This is the first public release of Latex2MathML. Lots are left to add and fix. I encourage you to test it. If something goes wrong, send me the lo...MapWindow GIS: MapWindow 6.0 msi (March 9): This fixes a bug with saving and opening maps.Microsoft Research Biology Extension for Excel: MSR Biology Extension for Excel - Beta 2 (Update): This is an updated release for the Beta 2 Installer for the MSR Biology Extension for Excel. A couple of identified issues with the installation f...Notes: Notes 5.2: This is the latest version of Notes (5.2). It has an installer - it will create a directory 'CPascoe' in My Documents. Once you have extracted the...Notes: Source Code: This has the all the code for Notes in a Text file.RedBulb for XNA Framework: Tree Massacre XMAS Edition (Sample): Tree Massacre XMAS Edition Source Code and Creators Club Package http://bayimg.com/image/jalkiaacb.jpgRoTwee: RoTwee (7.0.2.0): Now color mode is introduced to RoTwee. Push change color button and you can change color mode of RoTwee. Recommended mode is active rainbow mode :)SharePoint Team-Mailer: SharePoint Team-Mailer v1.0: Recommended versionsPWadmin: pwAdmin v0.7_nightly: Nightly Build --------------------- + Target JRE -> 1.5.0_21 + Target ApplicationServer -> Apache Tomcat 5.5.28 + Added xml editor (only working fo...SQL Server PowerShell Extensions: 2.1 Production: Release 2.1 re-implements SQLPSX as PowersShell version 2.0 modules. SQLPSX consists of 9 modules with 133 advanced functions, 2 cmdlets and 7 scri...TMap for VS2010: TMap for VS2010 (MSF Agile) RC Release: Release of the TMap process template for VS2010 combined with the MSF Agile process template basd on the Release Candidate. The references to the g...TS3QueryLib.Net: TS3QueryLib.Net Version 0.19.14.0: Changelog Added property "IsClientRecording" to class "ClientListEntry" which is used in method "GetClientList" of QueryRunner class. 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Sample application gets...XNA 3D World Studio Content Pipeline: XNA 3DWS Content Pipeline: This is an rar file containing the latest content importer codeMost Popular ProjectsMetaSharpWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesASP.NET Ajax LibraryMost Active ProjectsUmbraco CMSRawrSDS: Scientific DataSet library and toolsjQuery Library for SharePoint Web ServicesBlogEngine.NETN2 CMSFasterflect - A Fast and Simple Reflection APIFarseer Physics Enginepatterns & practices – Enterprise LibraryCaliburn: An Application Framework for WPF and Silverlight

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• top Tweets SOA Partner Community – August 2012

  - by JuergenKress

  Send your tweets @soacommunity #soacommunity and follow us at http://twitter.com/soacommunity Lucas Jellema ?Published an article about organizing Fusion Middleware Administration: http://technology.amis.nl/2012/07/31/organizing-fusion-middleware-administration-in-a-smart-and-frugal-way … - many organizations are struggling with this. ServiceTechSymposium Countdown to the Early Bird Registration Discount deadline. Only 4 days left! http://ow.ly/cBCiv demed ?Good chatting w Bob Rhubart, Thomas Erl & Tim Hall on SOA & Cloud Symposium https://blogs.oracle.com/archbeat/entry/podcast_show_notes_thomas_erl … @soaschool @OTNArchBeat -- CU in London! SOA Community top Tweets SOA Partner Community July 2012 - are you one of them? If yes please rt! https://soacommunity.wordpress.com/2012/07/30/top-tweets-soa-partner-community-july-2012/ … #soacommunity SOA Community ?Are You a facebook member - do You follow http://www.facebook.com/soacommunity ? #soacommunity #soa SOA Community ?SOA 24/7 - Home Page: http://soa247.com/#.UBJsN8n3kyk.twitter … #soacommunity OracleBlogs ?Handling Large Payloads in SOA Suite 11g http://ow.ly/1lFAih OracleBlogs ?SOA Community Newsletter July 2012 http://ow.ly/1lFx6s OTNArchBeat Podcast Show Notes: Thomas Erl on SOA, Cloud, and Service Technology http://bit.ly/OOHTUJ SOA Community SOA Community Newsletter July 2012 http://wp.me/p10C8u-s7 OTNArchBeat ?OTN ArchBeat Podcast: Thomas Erl on SOA, Cloud, and Service Technology - Part 1 http://pub.vitrue.com/fMti OProcessAccel ?Just released! White Paper: Oracle Process Accelerators Best Practices http://www.oracle.com/technetwork/middleware/bpm/learnmore/processaccelbestpracticeswhitepaper-1708910.pdf … OTNArchBeat ?SOA, Cloud, and Service Technologies - Part 1 of 4 - A conversation with SOA, Cloud, and Service Technology Symposiu... http://ow.ly/1lDyAK OracleBlogs ?SOA Suite 11g PS5 Bundled Patch 3 (11.1.1.6.3) http://ow.ly/1lCW1S Simon Haslam My write-up of the virtues of the #ukoug App Server & Middleware SIG http://bit.ly/LMWdfY What's important to you for our next meeting? SOA Community SOA Partner Community Survey 2012 http://wp.me/p10C8u-qY Simone Geib ?RT @jswaroop: #Oracle positioned in the Leader's quadrant - Gartner Magic Quadrants for Application Infrastructure (SOA & SOA Gov)... ServiceTechSymposium New Supporting Organization, IBTI has joined the Symposium! http://www.servicetechsymposium.com/ orclateamsoa ?A-Team Blog #ateam: BPM 11g Task Form Version Considerations http://ow.ly/1lA7XS OTNArchBeat Oracle content at SOA, Cloud and Service Technology Symposium (and discount code!) http://pub.vitrue.com/FPcW OracleBlogs ?BPM 11g Task Form Version Considerations http://ow.ly/1lzOrX OTNArchBeat BPM 11g #ADF Task Form Versioning | Christopher Karl Chan #fusionmiddleware http://pub.vitrue.com/0qP2 OTNArchBeat Lightweight ADF Task Flow for BPM Human Tasks Overview | @AndrejusB #fusionmiddleware http://pub.vitrue.com/z7x9 SOA Community Oracle Fusion Middleware Summer Camps in Lisbon report by Link Consulting http://middlewarebylink.wordpress.com/2012/07/20/oracle-fusion-middleware-summer-camps-in-lisbon/ … #ofmsummercamps #soa #bpm SOA Community ?Clemens Utschig-Utschig & Manas Deb The Successful Execution of the SOA and BPM Vision Using a Business Capability Framework: Concepts… Simone Geib ?RT @oprocessaccel: Just released! White Paper: Oracle Process Accelerators Best Practices http://www.oracle.com/technetwork/middleware/bpm/learnmore/processaccelbestpracticeswhitepaper-1708910.pdf … jornica ?Report from Oracle Fusion Middleware Summer Camps in Munich: SOA Suite 11g advanced training experiences @soacommunity http://bit.ly/Mw3btE Simone Geib ?Bruce Tierney: Update - SOA & BPM Customer Insights Webcast Series: | https://blogs.oracle.com/SOA/entry/update_soa_bpm_customer_insights … OTNArchBeat Business SOA: Thinking is Dead | @mosesjones http://pub.vitrue.com/k8mw esentri ?had 3 great days in Munich at #Oracle #soacommunity Summercamp! Special thanks to Geoffroy de Lamalle from eProseed! Danilo Schmiedel ?Used my time in train to setup the ps5 soa/bpm vbox-image.Works like a dream. Setup-Readme is perfect! Saves a lot of time!!! @soacommunity 18 Jul SOA Community ?THANKS for the excellent OFM summer camps - save trip home - share your pictures at http://www.facebook.com/soacommunity #ofmsummercamps #soacommunity doors BBQ-party with Oracle @soacommunity. 5Star! #lovemunich #ofmsummercamps pic.twitter.com/ztfcGn2S leonsmiers ?New #Capgemini blog post "Continuous Improvement of Business Agility" http://bit.ly/Lr0EwG #bpm #yam Eric Elzinga ?MDS Explorer utility, http://see.sc/4qdb43 #soasuite ServiceTechSymposium ?@techsymp New speaker Demed L’Her from Oracle has been added to the symposium calendar. http://ow.ly/cjnyw SOA Community ?Last day of the Fusion Middleware summer camps - we continue at 9.00 am. send us your barbecue pictures! #ofmsummercamps #soacommunity SOA Community ?Delivering SOA Governance with EAMS and Oracle Enterprise Repository by Link Consulting http://middlewarebylink.wordpress.com/2012/06/26/delivering-soa-governance-with-eams-and-oracle-enterprise-repository/ … #soacommunity #soa #oer OracleBlogs ?Process Accelerator Kit http://ow.ly/1loaCw 15 Jul SOA Community ?Sun is back in Munich! Send your pictures Middleware summer camps! #ofmsummercamps We start tomorrow 11.00 at Oracle pic.twitter.com/6FStxomk Walter Montantes ?Gracias, Obrigado, Thank you, Danke a Lisboa y a @soacommunity @wlscommunity. From the Mexican guys!! cc @mikeintoch #ofmsummercamps Andrejus Baranovskis Tips & Tricks How to Run Oracle BPM 11g PS5 Workspace from Custom ADF 11g Application http://fb.me/1zOf3h2K8 JDeveloper & ADF ?Fusion Apps Enterprise Repository - Explained http://dlvr.it/1rpjWd Steve Walker ?Oracle #Exalogic is the logical choice for running business applications. Exalogic Software 2.0 launches 7/25. Reg at http://bit.ly/NedQ9L A. Chatziantoniou ?Landed in rainy Amsterdam after a great week in Lisbon for the #ofmsummercamps - multo obrigado for Jürgen for another fantastic event SOA Community ?Teams present #BPM11g POC results at #ofmsummercamps - great job! #soacommunity pic.twitter.com/0d4txkWF Sabine Leitner ?#DOAG SIG Middleware 29.08.2012 Köln über MW, Administration, Monitoring http://bit.ly/P47w82 @soacommunity @OracleMW @OracleFMW 12 Jul philmulhall ?Thanks @soacommunity for a great week at the #ofmsummercamps. Hard work done so time for a few cold ones in Lisboa. pic.twitter.com/LVUUuwTh peter230769 ?RT: andrea_rocco_31: RT @soacommunity: Enjoy the networking event at #ofmsummercamps want to attend next time ... pic.twitter.com/D1HRndi4 Niels Gorter ?#ofmsummercamps dinner in Lisbon. Great weather, scenery, training, people, on and on. Big THANKS @soacommunity JDeveloper & ADF ?Running Oracle BPM 11g PS5 Worklist Task Flow and Human Task Form on Non-SOA Domain http://dlvr.it/1r0c2j Andrea Rocco ?RT @soacommunity: Jamy pastry at cafe Belem - who is the ghost there?!? http://via.me/-2x33uk6 Simon Haslam ?Sounds great - sorry I couldn't make it. RT @soacommunity: 6pm BPM advanced training hard work to build the POC #ofmsummercamps philmulhall ?A well earned rest after a hard days work @soacommunity #summercamps pic.twitter.com/LKK7VOVS philmulhall ?Some more hard working delegates @soacommunity #summercamps pic.twitter.com/gWpk1HZh SOA Community ?Error message at the BPM POC - will The #ace director understand the message and solve it? #ofmsummercamps pic.twitter.com/LFTEzNck Daniel Kleine-Albers ?posted on the #thecattlecrew blog: Assigning more memory to JDeveloper http://thecattlecrew.wordpress.com/2012/07/10/jdeveloper-quicktip-assigning-more-memory/ … OTNArchBeat ?BAM design pointers | Kavitha Srinivasan http://pub.vitrue.com/TOhP SOA Community ?Did you receive the July SOA community newsletter? read it! Want to become a member http://www.oracle.com/goto/emea/soa #soacommunity #soa #opn OracleBlogs ?Markus Zirn, Big Data with CEP and SOA @ SOA, Cloud &amp; Service Technology Symposium 2012 http://ow.ly/1lcSkb Andrejus Baranovskis Running Oracle BPM 11g PS5 Worklist Task Flow and Human Task Form on Non-SOA Eric Elzinga ?Service Facade design pattern in OSB, http://bit.ly/NnOExN Eric Elzinga ?New BPEL Thread Pool in SOA 11g for Non-Blocking Invoke Activities from 11.1.1.6 (PS5), http://bit.ly/NnOc2G Gilberto Holms New Post: Siebel Connection Pool in Oracle Service Bus 11g http://wp.me/pRE8V-2z Oracle UPK & Tutor ?UPK Pre-Built Content Update: UPK pre-built content development efforts are always underway and growing. Ove... http://bit.ly/R2HeTj JDeveloper & ADF ?Troubleshooting BPMN process editor problems in 11.1.1.6 http://dlvr.it/1p0FfS orclateamsoa ?A-Team Blog #ateam: BAM design pointers - In working recently with a large Oracle customer on SOA and BAM, I discove... http://ow.ly/1kYqES SOA Community BPMN process editor problems in 11.1.1.6 by Mark Nelson http://redstack.wordpress.com/2012/06/27/bpmn-process-editor-problems-in-11-1-1-6 … #soacommunity #bpm OTNArchBeat ?SOA Learning Library: free short, topic-focused training on Oracle SOA & BPM products | @SOACommunity http://pub.vitrue.com/NE1G Andrejus Baranovskis ?ADF 11g PS5 Application with Customized BPM Worklist Task Flow (MDS Seeded Customization) http://fb.me/1coX4r1X1 OTNArchBeat ?A Universal JMX Client for Weblogic –Part 1: Monitoring BPEL Thread Pools in SOA 11g | Stefan Koser http://pub.vitrue.com/mQVZ OTNArchBeat ?BPM – Disable DBMS job to refresh B2B Materialized View | Mark Nelson http://pub.vitrue.com/3PR0 SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit  www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Technorati Tags: SOA Community twitter,SOA Community,Oracle SOA,Oracle BPM,BPM Community,OPN,Jürgen Kress

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• How to find and fix performance problems in ORM powered applications

  - by FransBouma

  Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

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• Real Life Pixar Lamp Can’t Get Enough Of Human Interaction

  - by Jason Fitzpatrick

  This curious lamp, powered by an Arduino board and servo motors, is just as playful as the on-screen counterpart that inspired its creation. The New Zealand Herald reports on the creation of the lamp, seen in action in the video above: The project is a collaborative effort by Victoria University students Shanshan Zhou, Adam Ben-Gur and Joss Doggett, who met in a Physical Computing class. The lamp’s movements are informed by a webcam with an algorithm working behind it. Robotics and facial recognition technology enable the lamp to search for faces in the images from its webcam. When it spots a face, it follows as if trying to maintain eye contact. How to Access Your Router If You Forget the Password Secure Yourself by Using Two-Step Verification on These 16 Web Services How to Fix a Stuck Pixel on an LCD Monitor

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• How can Swift be so much faster than Objective-C in these comparisons?

  - by Yellow

  Apple launched its new programming language Swift at WWDC14. In the presentation, they made some performance comparisons between Objective-C and Python. The following is a picture of one of their slides, of a comparison of those three languages performing some complex object sort: There was an even more incredible graph about a performance comparison using the RC4 encryption algorithm. Obviously this is a marketing talk, and they didn't go into detail on how this was implemented in each. I leaves me wondering though: How can a new programming language be so much faster? Are the Objective-C results caused by a bad compiler or is there something less efficient in Objective-C than Swift? How would you explain a 40% performance increase? I understand that garbage collection/automated reference control might produce some additional overhead, but this much?

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• Algorithmia Source Code released on CodePlex

  - by FransBouma

  Following the release of our BCL Extensions Library on CodePlex, we have now released the source-code of Algorithmia on CodePlex! Algorithmia is an algorithm and data-structures library for .NET 3.5 or higher and is one of the pillars LLBLGen Pro v3's designer is built on. The library contains many data-structures and algorithms, and the source-code is well documented and commented, often with links to official descriptions and papers of the algorithms and data-structures implemented. The source-code is shared using Mercurial on CodePlex and is licensed under the friendly BSD2 license. User documentation is not available at the moment but will be added soon. One of the main design goals of Algorithmia was to create a library which contains implementations of well-known algorithms which weren't already implemented in .NET itself. This way, more developers out there can enjoy the results of many years of what the field of Computer Science research has delivered. Some algorithms and datastructures are known in .NET but are re-implemented because the implementation in .NET isn't efficient for many situations or lacks features. An example is the linked list in .NET: it doesn't have an O(1) concat operation, as every node refers to the containing LinkedList object it's stored in. This is bad for algorithms which rely on O(1) concat operations, like the Fibonacci heap implementation in Algorithmia. Algorithmia therefore contains a linked list with an O(1) concat feature. The following functionality is available in Algorithmia: Command, Command management. This system is usable to build a fully undo/redo aware system by building your object graph using command-aware classes. The Command pattern is implemented using a system which allows transparent undo-redo and command grouping so you can use it to make a class undo/redo aware and set properties, use its contents without using commands at all. The Commands namespace is the namespace to start. Classes you'd want to look at are CommandifiedMember, CommandifiedList and KeyedCommandifiedList. See the CommandQueueTests in the test project for examples. Graphs, Graph algorithms. Algorithmia contains a sophisticated graph class hierarchy and algorithms implemented onto them: non-directed and directed graphs, as well as a subgraph view class, which can be used to create a view onto an existing graph class which can be self-maintaining. Algorithms include transitive closure, topological sorting and others. A feature rich depth-first search (DFS) crawler is available so DFS based algorithms can be implemented quickly. All graph classes are undo/redo aware, as they can be set to be 'commandified'. When a graph is 'commandified' it will do its housekeeping through commands, which makes it fully undo-redo aware, so you can remove, add and manipulate the graph and undo/redo the activity automatically without any extra code. If you define the properties of the class you set as the vertex type using CommandifiedMember, you can manipulate the properties of vertices and the graph contents with full undo/redo functionality without any extra code. Heaps. Heaps are data-structures which have the largest or smallest item stored in them always as the 'root'. Extracting the root from the heap makes the heap determine the next in line to be the 'maximum' or 'minimum' (max-heap vs. min-heap, all heaps in Algorithmia can do both). Algorithmia contains various heaps, among them an implementation of the Fibonacci heap, one of the most efficient heap datastructures known today, especially when you want to merge different instances into one. Priority queues. Priority queues are specializations of heaps. Algorithmia contains a couple of them. Sorting. What's an algorithm library without sort algorithms? Algorithmia implements a couple of sort algorithms which sort the data in-place. This aspect is important in situations where you want to sort the elements in a buffer/list/ICollection in-place, so all data stays in the data-structure it already is stored in. PropertyBag. It re-implements Tony Allowatt's original idea in .NET 3.5 specific syntax, which is to have a generic property bag and to be able to build an object in code at runtime which can be bound to a property grid for editing. This is handy for when you have data / settings stored in XML or other format, and want to create an editable form of it without creating many editors. IEditableObject/IDataErrorInfo implementations. It contains default implementations for IEditableObject and IDataErrorInfo (EditableObjectDataContainer for IEditableObject and ErrorContainer for IDataErrorInfo), which make it very easy to implement these interfaces (just a few lines of code) without having to worry about bookkeeping during databinding. They work seamlessly with CommandifiedMember as well, so your undo/redo aware code can use them out of the box. EventThrottler. It contains an event throttler, which can be used to filter out duplicate events in an event stream coming into an observer from an event. This can greatly enhance performance in your UI without needing to do anything other than hooking it up so it's placed between the event source and your real handler. If your UI is flooded with events from data-structures observed by your UI or a middle tier, you can use this class to filter out duplicates to avoid redundant updates to UI elements or to avoid having observers choke on many redundant events. Small, handy stuff. A MultiValueDictionary, which can store multiple unique values per key, instead of one with the default Dictionary, and is also merge-aware so you can merge two into one. A Pair class, to quickly group two elements together. Multiple interfaces for helping with building a de-coupled, observer based system, and some utility extension methods for the defined data-structures. We regularly update the library with new code. If you have ideas for new algorithms or want to share your contribution, feel free to discuss it on the project's Discussions page or send us a pull request. Enjoy!

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• CodePlex Daily Summary for Tuesday, May 04, 2010

  CodePlex Daily Summary for Tuesday, May 04, 2010New ProjectsAlbum photo de club - Club's Photos Album: Un album photos permettant d'afficher les photos et le détails des membres d'un club - Photo album allowing to view photos and details of the membersBlog.Net Blogging Components: Blog.Net server-side blogging components to add a blog to your current ASP.NET website.FilePirate - Really Advanced LAN File Sharing: Really Advanced, yet super easy, LAN Party File Sharing written using the .Net Framework and C#. Ditch DirectConnect or Windows File Sharing at y...Fisiogest: Programa de gestión de una clínica de fisioterapiaIdeaNMR: An online repository of NMR experiment automated setups with wiki type documentation library and client program providing automated experiment setu...Introducción a Unity: Código de ejemplo del uso de Unity en diferentes situaciones. - Registro de clases, instancias e interfaces. - Resolución de clases, instancias e...Iowa City .NET Developers: This is the project site for the Iowa City .NET Developers.isanywhere: A command line utility to see if one or more files (given a filemask) are to be found anywhere inside a specific directory, or elsewhere inside one...LczCode: lczLog4net udp logs viewer: UdpLogViewer is a .NET 4 WinForm application that receives udp messages from log4net and shows them in a grid. It is possible to filter them or sh...New Silverlight XPS Viewer (In Sl4): New Silverlight XPS viewer Novuz: Novuz is a usenet indexer and reporter. It's developed both in Visual Studio 2010 and MonoDevelop, one of the key features of Novuz is that it sho...PodSnatch: PodSnatch is a podcast client that makes it easy to download rss-enclosures. Multiple simultaneous downloads enabled by threading. GUI is built wi...Robot Shootans: A simple top down shooter game where the player has to kill robots running at them. Written in C++ using SDL with various extentionsSharePoint Rsync List: This program will syncronize files and directories from and unc/local/sharepoint to a SharePoint 2007 or 2010 server. Supports of to 2GB files and ...SignInAndStorageLib: SignInAndStorageLib makes properly handling both sign in and storage issues in Xbox 360 XBLIG XNA games simple. Written in C#, SignInAndStorageLib...SilverBBS: ANSI-style bbs experience delivered via Silverlight. Silverlight flip-down counter: A Silverlight widget that enables you to count down towards a preconfigured event on a configured date.SmartieFly: Smartie Fly is a quiz software program written in C# using Silverlight. It uses SQL Server as a backend database. VS2010 Framework Driven Testing: CodedUITests generate a lot of code, and they break on every change to the object under test. Goals: - write new tests manually, but with as litt...WMediaCatalog: Advanced multimedia cataloguer. Allows users to keep their musical collections well organized and provides flexible methods of filtering, serarching WPathFinder: A simple path management application for windows. Functionality includes: - Add/remove/change path entries easily. - Search for all instances of a...Yasminoku: Yasminoku is an open source "Sudoku" alike game totally written in DHTML (JavaScript, CSS and HTML) that uses mouse. Includes sudoku solver. This c...New ReleasesAlbum photo de club - Club's Photos Album: App - version 0.4: version 0.4 - Critère d'affichage des membres : nom, année, ville - Navigation entre les images d'un membres - Navigation entre les membres - Affi...Album photo de club - Club's Photos Album: Code - Version 0.4: Code source de la version 0.4BigDecimal: Concept Evaluation Release 2 (BigDecimals): This in the second updates release of BigDecimals. It has the four simple arithmetic rules Addition, Subtract, Multiple and Division.CBM-Command: 2010-05-03: New features in this build Keyboard Shortcuts Panel Swapping Panel Toggling On/Off Toggling 40/80 Columns Confirming Quit Confirming GO64...Directory Linker: Directory Linker 2: This release introduces Undo Support and Symbolic File Link support. More details can be found here http://www.humblecoder.co.uk/?p=141DotNetNuke Skins Pack: DotNetNuke 80 Skins Pack: This released is the first for DNN 4 & 5 with Skin Token Design (legacy skin support on DNN 4 & 5)DTLoggedExec: 1.0.0.0: -FIRST NON-BETA RELEASE! :) -Code cleaned up -Added SetPackageInfo method to ILogProvider interface to make easier future improvements -Deprecated...GenerateTypedBamApi: Version 2.1: Changes in this release: NEW: Support for Office Data Connectivity Components 2010 NEW: Include both x86 and x64 EXE's due to lack of support in ...HobbyBrew Mobile: Beta 1 Refresh: Risolto bug circa il salvataggio di ricette (veniva impostato scorrettamente che si trattava di Mash Design "infusione" se ri-aperte con hobbyBrew)...Home Access Plus+: v4.2: Version 4.2 Added Overrides into the Booking System Some slight CSS changes to the Help Desk Updated the config tool to work anywhere on the LA...Hubble.Net - Open source full-text search database: V0.8.3.0: V0.8.3.0 Show server version in about dialog. Fix a bug of deleting querycache files. V0.8.2.9 Change sql client to support userid and password Ch...IdeaNMR: IdeaNMR Client: This is a client program with an example package.kdar: KDAR 0.0.21: KDAR - Kernel Debugger Anti Rootkit - signature's bases updated - usability increased - NDIS6 MINIPORT_BLOCK checks addedLightWeight Application Server: 0.4.1: One step further to beta - yet another release for c# developers audience only. Changes: 1. API - added a LWAS.Infrastructure.Storage service to d...Log4net udp logs viewer: UdpLogViewer 1.0: First release of UdpLogViewer, version 1.0.MDownloader: MDownloader-0.15.11.58370: Fixed minor bugs.Metabolite Enterprise Libraries for EPiServer CMS using Page Type Builder: Metabolite Enterprise Libraries 1.2 Beta 2: This is the beta release of the Metabolite Enterprise Libraries 1.2 Beta 2 for use with EPiServer 6 and Page Type Builder 1.2 Beta 2.Microsoft Silverlight Analytics Framework: Version 1.4.3 Installer: Pre-release Installer for Visual Studio 2010 and Expression Blend 4 RCSupports both Silverlight 3 and Silverlight 4 Release NotesFixed null referen...MultipointTUIO: Multipoint SDK v1.5 Release: Rebuilt against v1.5 of the Microsoft Multipoint SDK, this mean Windows 7 support (and 64bit I think!)My Notepad: My Notepad: This is the status of My Notepad until now. This is many built in features but has to undergo a lot of modifications. The release does not include ...New Silverlight XPS Viewer (In Sl4): Silverlight XPS Viewer: Background: During my development last week I was working on a Silverlight based XPS viewer. During this viewer we came to a situation in which the...NSIS Autorun: NSIS Autorun 0.1.6: This release includes source code, executable binary, files and example materials.Open Diagram: Open Diagram 5.0 Beta May 2010: This is the first beta release of Open Diagram 5.0. Select Crainiate.Diagramming.Examples.Forms as the startup project to view the current Class D...Pocket Wiki: PC Wiki (zip) 1.0.1: PC Version of Pocket Wiki. Unzip and run. Requires .NET Framework 2.0Pocket Wiki: Pocket Wiki 1.0.1 (cab): Pocket Wiki cab installation - requires DotNet 2.0 or greater. Default wiki language is "slash" - a syntax I created that is easy to type on keyboa...Pocket Wiki: Pocket Wiki.sbp: Pocket Wiki Source Code (version .72) - Basic4PPCPublish to Photo Frame: 1.0.2.0: This version adds: add borders to portrait images, for photo frames that crop them incorrectly.Reflection Studio: Reflection Studio 0.1: First download release, it contains a lot of things but allways in beta version. Hope you will like the preview.SharePoint 2010 PowerShell Scripts & Utilities: PSSP2010 Utils 0.1: This is the initial release with SPInstallUtils.psm1 module. This module includes Get-SPPrerequisites and New-SPInstallPackage cmdlets. Refer to th...Silverlight 4.0 Popup Menu: Context Menu for Silverlight 4.0 v1.1 Beta: Multilevel menus are now supported. Added design time support for the PopupMenuItem elements. The project is now under Subversion.Silverlight flip-down counter: FlipDownCounter v1.0: The final release of the Silverlight flip-down counter. Please refer to the included readme file for information on how to use the counter.Stratosphere: Stratosphere 1.0.0.1: Moved scalable block file system implementation to Stratosphere.FileSystemSystem.AddIn Pipeline Builder: Pipeline Builder 1.2: Lots of improvements from the CTP, version 1.0: - Added dialogue for possible overwrite if the file has changed: possibility of ignoring changes (p...ThoughtWorks Cruise Notification Interceptor: 1.0.1: Fixed an issue with the regex that parses the incoming notification. This issue would send failure messages when the build was "fixed".ThreadSafeControls: ThreadSafeControls v0.1: This is the first binary release of the ThreadSafeControls library. I'll call it a pre-alpha release.TracerX Logger/Viewer for .NET: 4.0: View this CodeProject article for documentation on how to use the latest version of the Logger. About the DownloadsVersion: 4.0.1005.1163 Changese...VCC: Latest build, v2.1.30503.0: Automatic drop of latest buildVisual Studio DSite: Lottery Game (Visual C++ 2008): An advanced lottery game made in visual c 2008.VivoSocial: VivoSocial 7.1.3: Version 7.1.3 of VivoSocial has been released. If you experienced any issues with the previous version, please update your modules to the 7.1.3 rel...Xrns2XMod: Xrns2XMod 1.0: Features added Conversion of all possible convertible features between Renoise and MOD / XM. FlacBox lib updated (thanks to Yuri) NAudio lib in...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: Databasepatterns & practices – Enterprise LibrarySilverlight ToolkitiTuner - The iTunes CompanionWindows Presentation Foundation (WPF)ASP.NETDotNetNuke® Community EditionMost Active ProjectsIonics Isapi Rewrite Filterpatterns & practices – Enterprise LibraryRawrHydroServer - CUAHSI Hydrologic Information System ServerAJAX Control Frameworkpatterns & practices: Azure Security GuidanceNB_Store - Free DotNetNuke Ecommerce Catalog ModuleBlogEngine.NETTinyProjectDambach Linear Algebra Framework

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• Your Day-by-Day Guide to Agile PLM at Oracle OpenWorld 2012

  - by Kerrie Foy

  This year’s Oracle OpenWorld conference is nearly here, and we’re all excited about what we have planned! With five days of activities and customer presenters from market leaders and top innovators like The Coca-Cola Company, Starbucks, JDSU, Facebook, GlobalFoundries, and more, this is an event you don't want to miss. I've compiled this day-by-day guide to help anyone keep track of all the “Product Lifecycle Management and Product Value Chain” sessions and activities at OpenWorld 2012, September 30 – October 4 in San Francisco, California.  Monday, October 1 There are great networking activities on Sunday September 30, but PLM specific sessions start after general conference keynotes on Monday, October 1 at 10:45 a.m. at the InterContinental Hotel in room Telegraph Hill. In fact, most of our sessions this year will be held in this room, which is still close to the conference keynotes in Moscone, but just far enough away to allow some focused networking and discussions.   This first session, 10:45 – 11:45 a.m. is a joint session with the Agile and AutoVue teams, entitled “Streamline PLM Design-to-Manufacturing Processes with AutoVue Visualization Soltuions” featuring presenters from Oracle as well as joint AutoVue and Agile PLM customer GlobalFoundries. In the following 12:15 – 1:15 p.m. slot, there are two sessions to choose from, so if you have a team of representatives attending OpenWorld, you may consider splitting up to catch both of these: a) Our General Session will be held in the InterContinental Hotel Ballroom C, which will cover our complete enterprise PLM strategy, product updates, and roadmaps. It’s our pleasure to feature a customer keynote presentation from Chris Bedi, CIO, and Rajeev Sethi, Director IT Business Engagement, of JDSU. b) A focused session on integrating PLM with Engineering and Supply Chain Systems will be held on the second floor of Moscone West (next to the InterContinental) in room 2022. Join to discover how these types of integrations help companies manage common and integrated design information across all MCAD, ECAD, and software components. After a lunch break and perhaps a visit to the Demogrounds in Moscone West, select from two product roadmap sessions in the next time slot (3:15 – 4:15 p.m.): an Agile 9.3.x session located in the InterContinental’s Ballroom C, and an Agile PLM for Process session located back in the InterContinental’s Telegraph Room. Both sessions will have strong content around each product line’s latest releases, vision, and customer examples. We are very pleased to feature Daniel Soosai of Facebook in the A9 session and Vinnie D’Agostino of The Coca-Cola Company in the PLM for Process session. Afterwards, hang in there for one last session of the day from 4:45 – 5:45 p.m.; it’s an insightful discussion on leveraging Agile PLM as the Foundation for Enterprise Quality Management, and it’s sure to be one of the best. In the Telegraph Room, this session will feature Oracle experts, partner co-presenter David Bartlett from CPG Solutions, and customer co-presenter Thomas Crowe, CIO of PL Developments. Hear their experience around implementing collaborative, integrated solutions to ensure effective knowledge transfer throughout an organization, and how to perform analysis in real time to resolve product quality issues swiftly and efficiently. On Monday evening there will be plenty of industry, product, and partner dinners, so take advantage of all the networking opportunities and catch some great tunes at the 5 day Oracle OpenWorld Music Festival! Tuesday, October 2 Tuesday starts early with a special PLM Networking Brunch, sponsored by several partners, from 8:30 a.m. – 10:30 a.m. at the B Restaurant that sits atop Yerba Buena Gardens. You’ll have the unique opportunity to meet with like-minded industry peers and a PLM partner to discuss a topic of your choosing while enjoying a delicious meal. Registration is required, so to inquire about attending this brunch, please email Terri.Hiskey-AT-oracle.com. After wrapping up your conversations over brunch, head over to the Marriott Marquis in the Nob Hill CD room for a chance to experience the Oracle Product Lifecycle Analytics solution in a Hands-On Lab, open from 10:15 a.m. – 12:45 p.m. Experts will be there to answer your questions. Back in the InterContinental Hotel’s Telegraph room, the session on “Ideation and Requirements Management: Capturing the Voice of the Customer” begins at 11:45 a.m. – 12:45 p.m. This may be the session for you if you’re struggling with challenges like too many repositories of customer needs, requests, and ideas; limited visibility into which ideas are being advanced by customers and field resources; or if you’re unable to leverage internal expertise to expose effort and potential risks. This session will discuss how Agile PLM can help you overcome ideation challenges to deliver the right products to their targeted markets and fulfill customer desires. Next, from 1:15 – 2:15 p.m. join us for a session on Managing Profitable Innovation with Oracle Product Lifecycle Analytics. If you missed the Hands-on Lab, have more questions, or simply want to be inspired by the product’s forward-thinking vision and capabilities, this is a great opportunity to meet the progressive-minded executives behind the application. After this session, it may be a good opportunity to swing by the Demogrounds in Moscone West and visit the Agile PLM demos at exhibit booths #81 for Agile PLM for Discrete Manufacturing, #70 for Agile PLM for Process, and #82 for AutoVue and Agile PLM Enterprise Visualization. Check out the related Supply Chain Management booths close by if you’re interested - here's the map. There’s always lots to see and do around the exhibit area. But don’t forget the last session of the day from 5:00 p.m. – 6:00 p.m. in Telegraph Hill on Managing Product Innovation and Compliance in Life Science Companies, a “must-see” if you’re in this industry. Launching innovative products quickly is already a high-stakes challenge, but companies in the life sciences industry face uniquely severe consequences when new products don’t perform or comply as required. In recent years, more and more regulations have become mandatory, and new ones, such as REACH, are currently going into effect for several companies. Customer presenters from pharmaceutical leader Eli Lilly will share how they’ve leveraged Agile PLM to deliver high-quality, innovative products in a fast-paced, heavily regulated market environment. Tuesday evening unwind at the Supply Chain Management Reception from 6:00 – 8:00 p.m. at the premier boutique Roe Nightclub and Lounge, which is located about three blocks down on Howard Street (on the other side of Moscone from the InterContinental Hotel). Registration is required. Click here for the details.   Wednesday, October 3 We have another full line-up on Wednesday, so be ready for an action-packed day. We start with a session at 10:15 – 11:15 a.m. in the Telegraph Room where we have a session on “PLM for Consumer Products: Building an Engine for Quality and Innovation” with featured presenters from Starbucks and partner Kalypso. This is a rare opportunity to learn directly from Starbucks how they instill quality and innovation throughout their organization, products, and processes, leveraging PLM disciplines with strong support from their partner.  If you’re not in the consumer products industry, we recommend attending another session at 10:15 – 11:15 a.m. in Moscone West room 3005: “Eco-Enterprise Innovation Awards and the Business Case for Sustainability” featuring Jeff Henley, Oracle’s Chairman of the Board and Jon Chorley, Chief Sustainability Officer. Oracle will honor select customers with Oracle’s Eco-Enterprise Innovation award, which recognizes customers and their respective partners who rely on Oracle products to support their green business practices to reduce their environmental impact while improving business efficiencies and reducing costs. The awards presentation is followed by a panel discussion with customers and Oracle executives, who describe how these award-winning organizations are embracing environmental initiatives as a central part of their business strategy and how information technology plays a pivotal role. Next at 11:45 a.m. – 12:45 p.m. in Telegraph Hill attend our session devoted to exploring Product Lifecycle Management’s role in Software Lifecycle Management. This is a thought leadership session with Oracle experts in the field on the importance of change management, and we’ll discuss how Oracle has for years leveraged Agile PLM to develop Agile PLM. If software lifecycle management doesn’t apply to your business or you’d rather engage in some lively one-on-one discussions, we also have a “Supply Chain Meet the Experts” session in Moscone West Room 2001A. Product experts, thought leaders and executives will be on hand to discuss your questions/topics, so come prepared. This session tends to fill up fast so try to get in early. At 1:15 – 2:15 p.m. join us back in Telegraph Hill for a session focused on leveraging the Agile Product Portfolio Management application as the Product Development Master Schedule to improve efficiencies, optimize resources, and gain visibility across projects enterprise-wide to improve portfolio profitability. Customer presenters from Broadcom will explain how they’ve leveraged the product to enable a master schedule with enterprise-level, phase-gate program and project collaboration and resource optimization. Again in Telegraph Hill from 3:30 – 4:30 p.m. we have an interesting session with leading semiconductor customer LSI and partner Kalypso on how LSI leveraged Agile PLM to advance from homegrown applications to complete Product Value Chain Management. That type of transition can be challenging, and LSI details how they were able to achieve their goals and the value they gained along the journey – a fascinating account for any company interested in leveraging best practices to innovate their business processes and even end products. Lastly, we’ll wrap up in Telegraph Hill from 5:00 – 6:00 p.m. with a session on “Ensuring New Product Success by Achieving Excellence in New Product Introduction.” This is a cross-industry session, guaranteed to deliver insight in the often elusive practice of creating winning products, and we’re very excited about. According to IDC Manufacturing Insights analyst Joe Barkai, “Product Failures are not necessarily a result of bad ideas…they are a result of suboptimal decisions.” We’ll show you how to wire your business processes to enhance decision-making and maximize product potential. Now, quickly hit your hotel room to freshen up and then catch one of the many complimentary shuttles to the much-anticipated Oracle Customer Appreciation Event on Treasure Island. We have a very exciting show planned – check out what’s in store here. Thursday, October 4 PLM has a light schedule on Thursday this year with just one session, but this again is one of our best sessions on managing the Product Value Chain: at 11:15 a.m – 12:15 p.m.in Telegraph Hill, it’s a customer and partner driven session with Sonoco Products and Deloitte telling their story about how to achieve integrated change control by interfacing Agile PLM with Oracle E-Business Suite. Sonoco Products, a global manufacturer of consumer and industrial packaging materials, with its systems integrator, Deloitte, is doing this by implementing prebuilt integration (Oracle Design-to-Release Integration Pack for Agile Product Lifecycle Management for Process and Oracle Process) to integrate Agile with Oracle Product Hub/Oracle Product Information Management and Oracle E-Business Suite. This session presents a case study of how Sonoco is leveraging this solution to improve data quality and build a framework for stronger master data governance. Even though that ends our PLM line-up at OpenWorld, there will still be many sessions and activities at the conference, so visit the Oracle OpenWorld website to review agendas and build your schedule. And of course, download and bring this guide and the latest version of the Agile PLM Focus-On Document (available soon!). San Francisco is a wonderful city to explore, and we’re glad you’re considering joining the Agile PLM team at Oracle OpenWorld!  I hope to see you there! Follow me before the conference and on site for real-time updates about #OOW12 on Twitter @Kerrie_Foy or @AgilePLM.

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• CodePlex Daily Summary for Tuesday, April 27, 2010

  CodePlex Daily Summary for Tuesday, April 27, 2010New ProjectsActive Directory User Properties Change: A complete application in VS 2005 and VB.NET, for Request Request in User Details in Active Directory, with flow to HR and then to IT for approval ...AVR Terminal: A Windows application for connecting to an AVR via RS232 serial or USB-to-COM FTDI ports. Works on Arduino, Bare Bones Board, and any custom board...Battle Droids: AVR-based Network Combat!: A Battle Droid is an AVR® microcontroller running the BattleDroid firmware. This firmware turns your AVR into a lean, mean, fighting machine, and ...Camp Foundation: Camp Foundationchakma: chakma is a question - answer based web application to make people get questions from anybody around the world and being able to answer them. c...Document.Editor: Document.Editor is a multitab text editor for Windows. It includes plain and rich text format support, multi tab interface so you can edit multiple...Dot Net Marche Music Store Demo Application: This is a demo application that the DotNetMarche user gorup (www.dotnetmarche.org) use to make experiments and prepare demos for our workshopselivators: a monitor which enables the user to view the movement of the elivators in a buildingExtended SSIS Package Execute: The SSIS package execute task is flawed as it does not support passing variables. Here we have a custom task that will pass items in a dataflow as...File tools: File toolsFileExplorer.NET: FileExplorer.NET is a .net usercontrol which tries to mimic the Windows FileExplorer treeview.Kazuku: ASP.NET MVC 2 Content Management SystemKSharp Ajax Control Toolkit Library: Built ontop of the Microsoft ASP.NET Ajax Control Toolkit, this library offers enhanced versions of the controls found in the Ajax Control Toolkit....Nitrous - An Aspx ViewEngine for ASP.NET MVC: Near drop-in replacement ASP.NET ViewEngine for MVC.Open Data Protocol - Client Libraries: This is an Open Source release of the .NET and Silverlight Client Libraries for the Open Data Protocol (OData). For more information on odata, see ...ORAYLIS BI.SmartDiff: BI.SmartDiff is a helper to connect the functionality of BIDS Helper – SmartDiff to TortoiseSVN. BIDS Helper – SmartDiff helps you to get more read...RicciWebSiteSystem: soon websiteSynapse:Silverlight A Simple Silverlight Framework: Synapse:Silverlight is a simplified framework for Silverlight. It's purpose is to help developers and designers produce basic LOB solutions that do...TestProjectMB: Testing Team Foundation ServerThoughtWorks Cruise Notification Interceptor: Cruise notification interceptorThreadSafeControls: ThreadSafeControls is a C# project that greatly simplifies the process of transitioning Windows Forms applications to a multithreaded environment b...Unscrambler: Unscrambler is a multitouch WPF word game built with MVVM Light in order to show how to use the touch maniupation and inertia features included in ...Web Utilities: web utilitiesNew Releases7zbackup - PowerShell Script to Backup Files with 7zip: 7zBackup v. 1.7.1 Stable: Bug Solved : Presence of junction.exe is wrongly referred to 7z.exeAVR Terminal: AVR Terminal v0.2: Here is an Alpha-almost-BETA release of the AVR Terminal. That being said, I use it almost daily and it shouldn't break anything on your system, b...Bistro FSharp Extensions: 0.9.7.0: This is the VS 2010 release of BistroFS extensions. This release focused on usability, adding key functionality such as resource aliasing and secur...Bojinx: Bojinx Dialog Management V1.0: Stable release of the Bojinx Dialog Management library.BOWIE: BOWIE 2010: This new version works on Outlook 2007/2010 and TFS 2008/2010 RTM. Details about all features in this version on the Home Page : http://bowie.code...Catharsis: Catharsis 2.5 on catarsa.com: The Catharsis framework has finally its own portal http://catarsa.com Example - documented steps to create Web-Application http://catarsa.com/Arti...Colorful Expression: Expression Blend 3: Alpha Version, Read Issues and Installing! Colorful Expression is an add-in for Expression Blend and Expression Design that brings you the Adobe K...Colorful Expression: Expression Blend 4: Read Issues and Installing! Colorful Expression is an add-in for Expression Blend and Expression Design that brings you the Adobe Kuler and ColorLo...Courier: Version 1.0: This release includes integration with the Reactive Framework for more elegant message handling and allowing more succinct client code. Full suite...CRM 4.0 Contract Utilities: Release 1.0: Project Description List of Contract Utilities (i.e. custom workflow actions) 1. Change contract status from Active to Draft 2. Copy Contract (with...Document.Editor: 0.9.0: Whats New?: New icon set Bug fix'sDotNetNuke® Blog: 04.00.00: Minimum Required DNN Version: 4.06.02General Code organization * Converted project to .NET 3.5 * Converted solution to Visual Stud...EPiAbstractions: EPiAbstractions 1.2: Updated for EPiServer CMS 6. Only features abstractions for EPiServer CMS. For abstractions for EPiServer.Common and EPiServer.Community use versio...Fluent ViewModel Configuration for WPF (MVVM): FluentViewModel Alpha2: Added support for view model validation using FluentValidation (http://fluentvalidation.codeplex.com/) Fixed exception from Blend while in design...GArphics: Beta v0.9: Beta v0.9. Practically all of the planned features have been implemented and are available to the users. For the version 1.0 mainly just some minor...HTML Ruby: 6.22.2.1: Fixed a bug where HTML Ruby's options window will generate entries in the error log when applying option changes (regression from 6.21.8)HTML Ruby: 6.22.3: Add/remove stop spacing event listener as needed for possible fix to 4620iTuner - The iTunes Companion: iTuner 1.2.3768 Beta 3b: Beta 3 requires iTunes 9.1.0.79 or later A Librarian status panel showing active and queued Librarian scanners. This will be hidden behind the "bi...LiveUpload to Facebook: LiveUpload to Facebook 3.2.3: Version 3.2.3Become a fan on Facebook! Features Quickly and easily upload your photos and videos to Facebook, including any people tags added in W...Maintainance Schedule: Maintenance Scheduler: The first Alpha release of the project.NetSockets: NetSockets (1.2): The NetSockets library (DLL)NSIS Autorun: NSIS Autorun 0.1.2: NSIS Autorun 0.1.1 This release includes source code, application binary, and example materials.OpenSceneGraph glsl samples: OsgGlslSamples Win32 binaries: Project binary release for Windows. The effects shown are: Ambient Occlusion, Depth of Field, DoF with alpha channel, Fire effects, HDR, Light Ma...ORAYLIS BI.SmartDiff: ORAYLIS BI.SmartDiff 0.6.1: First public versionpatterns & practices - Windows Azure Guidance: Code Drop 4 - Content Complete: This release includes documentation and all code samples intended for this first guide. As before, this code release builds on the previous one an...Pex Custom Arithmetic Solver: Custom Solver Package: This is the custom solvers packaged together. To use simply include the dll in your project and add [assembly: PexCustomArithmeticSolver] to your P...PokeIn Comet Ajax Library: PokeIn v08 x86: New FeatureFrom this version forward, PokeIn will define a way between the main page and client side automaticly based to security level. Add "pub...Proxi [Proxy Interface]: Proxi Release 1.0.0.426: Proxi Release 1.0.0.426QuestTracker: QuestTracker 0.3: This release includes recurring quests! Now you can set a quest to uncomplete itself every X minutes, hours, or days! And the quests still retain t...Rensea Image Viewer: RIV 0.4.5: RIV Fix Version. You would need .NET Framework 4.0 to make it run RIVU Improved Version. With separated RIV up-loader, to upload images to Renjian...SCC Switch Provider: Provides a GUI to Switch Source Code Control Provi: Transferred from GotDotNet Workplace. Initial public Release. Downloaded ~922 times from original post.sTASKedit: sTASKedit v0.7a (Alpha): + Fixed: XOR text encoding + Fixed: adding timed rewards missing values + Fixed: occupations in clone()Synapse:Silverlight A Simple Silverlight Framework: Synapse Silverlight Alpha Release: Initial Road-map is being defined.ThoughtWorks Cruise Notification Interceptor: 1.0.0: Initial release.UDC indexes parser: UDC indexex parser Beta 2: Добавлена возможность работать с распределением определителей как если бы генератор был бы LALR(2) То что осталось: Если текстовое дополнение начи...Unscrambler: Release 1.0: Here's the first release of Unscrambler.WinXound: WinXound 3.3.0 Beta 2 for Mac OsX: New: Code Repository (for UDO and personal code) New: Format Code - Added the ability to format only the selected text of the code New: Explore...WPF Inspirational Quote Management System: Release 1.2.2: - Fixed issue some users were having when the application is minimised.Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitSilverlight Toolkitpatterns & practices – Enterprise LibraryMicrosoft SQL Server Product Samples: DatabaseWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesPHPExcelMost Active Projectspatterns & practices – Enterprise LibraryRawrGMap.NET - Great Maps for Windows Forms & PresentationParticle Plot PivotBlogEngine.NETNB_Store - Free DotNetNuke Ecommerce Catalog ModuleFarseer Physics EngineIonics Isapi Rewrite FilterN2 CMSDotNetZip Library

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• Difference Procedural Generation and Random Generation

  - by U-No-Poo

  Today, I got into an argument about the term "procedural generation". My point was that its different from "classic" random generation in the way that procedural is based on a more mathematical, fractal based, algorithm leading to a more "realistic" distribution and the usual randomness of most languages are based on a pseudo-random-number generator, leading to an "unrealistic", in a way, ugly, distribution. This discussion was made with a heightmap in mind. The discussion left me somehow unconvinced about my own arguments though, so, is there more to it? Or am I the one who is, in fact, simply wrong?

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