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• Possible to see % uploaded when uploading a file using a form?

  - by quantumpotato

  I'm attempting to submit my iPhone app to iTunesConnect. The pictures loaded fine, and I picked "submit binary later" because iTunesConnect kept having the connection reset. I'm using Firefox to upload the binary. Is there any way I can see the % or data transferred of a specific file uploading, in real time? It would be great to see that the bits haven't moved in a while and manually reload the page instead of waiting for the connection to reset. Cheers

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• Fast block placement algorithm, advice needed?

  - by James Morris

  I need to emulate the window placement strategy of the Fluxbox window manager. As a rough guide, visualize randomly sized windows filling up the screen one at a time, where the rough size of each results in an average of 80 windows on screen without any window overlapping another. It is important to note that windows will close and the space that closed windows previously occupied becomes available once more for the placement of new windows. The window placement strategy has three binary options: Windows build horizontal rows or vertical columns (potentially) Windows are placed from left to right or right to left Windows are placed from top to bottom or bottom to top Why is the algorithm a problem? It needs to operate to the deadlines of a real time thread in an audio application. At this moment I am only concerned with getting a fast algorithm, don't concern yourself over the implications of real time threads and all the hurdles in programming that that brings. So far I have two choices which I have built loose prototypes for: 1) A port of the Fluxbox placement algorithm into my code. The problem with this is, the client (my program) gets kicked out of the audio server (JACK) when I try placing the worst case scenario of 256 blocks using the algorithm. This algorithm performs over 14000 full (linear) scans of the list of blocks already placed when placing the 256th window. 2) My alternative approach. Only partially implemented, this approach uses a data structure for each area of rectangular free unused space (the list of windows can be entirely separate, and is not required for testing of this algorithm). The data structure acts as a node in a doubly linked list (with sorted insertion), as well as containing the coordinates of the top-left corner, and the width and height. Furthermore, each block data structure also contains four links which connect to each immediately adjacent (touching) block on each of the four sides. IMPORTANT RULE: Each block may only touch with one block per side. The problem with this approach is, it's very complex. I have implemented the straightforward cases where 1) space is removed from one corner of a block, 2) splitting neighbouring blocks so that the IMPORTANT RULE is adhered to. The less straightforward case, where the space to be removed can only be found within a column or row of boxes, is only partially implemented - if one of the blocks to be removed is an exact fit for width (ie column) or height (ie row) then problems occur. And don't even mention the fact this only checks columns one box wide, and rows one box tall. I've implemented this algorithm in C - the language I am using for this project (I've not used C++ for a few years and am uncomfortable using it after having focused all my attention to C development, it's a hobby). The implementation is 700+ lines of code (including plenty of blank lines, brace lines, comments etc). The implementation only works for the horizontal-rows + left-right + top-bottom placement strategy. So I've either got to add some way of making this +700 lines of code work for the other 7 placement strategy options, or I'm going to have to duplicate those +700 lines of code for the other seven options. Neither of these is attractive, the first, because the existing code is complex enough, the second, because of bloat. The algorithm is not even at a stage where I can use it in the real time worst case scenario, because of missing functionality, so I still don't know if it actually performs better or worse than the first approach. What else is there? I've skimmed over and discounted: Bin Packing algorithms: their emphasis on optimal fit does not match the requirements of this algorithm. Recursive Bisection Placement algorithms: sounds promising, but these are for circuit design. Their emphasis is optimal wire length. Both of these, especially the latter, all elements to be placed/packs are known before the algorithm begins. I need an algorithm which works accumulatively with what it is given to do when it is told to do it. What are your thoughts on this? How would you approach it? What other algorithms should I look at? Or even what concepts should I research seeing as I've not studied computer science/software engineering? Please ask questions in comments if further information is needed. [edit] If it makes any difference, the units for the coordinates will not be pixels. The units are unimportant, but the grid where windows/blocks/whatever can be placed will be 127 x 127 units.

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• Prefer extension methods for encapsulation and reusability?

  - by tzaman

  edit4: wikified, since this seems to have morphed more into a discussion than a specific question. In C++ programming, it's generally considered good practice to "prefer non-member non-friend functions" instead of instance methods. This has been recommended by Scott Meyers in this classic Dr. Dobbs article, and repeated by Herb Sutter and Andrei Alexandrescu in C++ Coding Standards (item 44); the general argument being that if a function can do its job solely by relying on the public interface exposed by the class, it actually increases encapsulation to have it be external. While this confuses the "packaging" of the class to some extent, the benefits are generally considered worth it. Now, ever since I've started programming in C#, I've had a feeling that here is the ultimate expression of the concept that they're trying to achieve with "non-member, non-friend functions that are part of a class interface". C# adds two crucial components to the mix - the first being interfaces, and the second extension methods: Interfaces allow a class to formally specify their public contract, the methods and properties that they're exposing to the world. Any other class can choose to implement the same interface and fulfill that same contract. Extension methods can be defined on an interface, providing any functionality that can be implemented via the interface to all implementers automatically. And best of all, because of the "instance syntax" sugar and IDE support, they can be called the same way as any other instance method, eliminating the cognitive overhead! So you get the encapsulation benefits of "non-member, non-friend" functions with the convenience of members. Seems like the best of both worlds to me; the .NET library itself providing a shining example in LINQ. However, everywhere I look I see people warning against extension method overuse; even the MSDN page itself states: In general, we recommend that you implement extension methods sparingly and only when you have to. (edit: Even in the current .NET library, I can see places where it would've been useful to have extensions instead of instance methods - for example, all of the utility functions of List<T> (Sort, BinarySearch, FindIndex, etc.) would be incredibly useful if they were lifted up to IList<T> - getting free bonus functionality like that adds a lot more benefit to implementing the interface.) So what's the verdict? Are extension methods the acme of encapsulation and code reuse, or am I just deluding myself? (edit2: In response to Tomas - while C# did start out with Java's (overly, imo) OO mentality, it seems to be embracing more multi-paradigm programming with every new release; the main thrust of this question is whether using extension methods to drive a style change (towards more generic / functional C#) is useful or worthwhile..) edit3: overridable extension methods The only real problem identified so far with this approach, is that you can't specialize extension methods if you need to. I've been thinking about the issue, and I think I've come up with a solution. Suppose I have an interface MyInterface, which I want to extend - I define my extension methods in a MyExtension static class, and pair it with another interface, call it MyExtensionOverrider. MyExtension methods are defined according to this pattern: public static int MyMethod(this MyInterface obj, int arg, bool attemptCast=true) { if (attemptCast && obj is MyExtensionOverrider) { return ((MyExtensionOverrider)obj).MyMethod(arg); } // regular implementation here } The override interface mirrors all of the methods defined in MyExtension, except without the this or attemptCast parameters: public interface MyExtensionOverrider { int MyMethod(int arg); string MyOtherMethod(); } Now, any class can implement the interface and get the default extension functionality: public class MyClass : MyInterface { ... } Anyone that wants to override it with specific implementations can additionally implement the override interface: public class MySpecializedClass : MyInterface, MyExtensionOverrider { public int MyMethod(int arg) { //specialized implementation for one method } public string MyOtherMethod() { // fallback to default for others MyExtension.MyOtherMethod(this, attemptCast: false); } } And there we go: extension methods provided on an interface, with the option of complete extensibility if needed. Fully general too, the interface itself doesn't need to know about the extension / override, and multiple extension / override pairs can be implemented without interfering with each other. I can see three problems with this approach - It's a little bit fragile - the extension methods and override interface have to be kept synchronized manually. It's a little bit ugly - implementing the override interface involves boilerplate for every function you don't want to specialize. It's a little bit slow - there's an extra bool comparison and cast attempt added to the mainline of every method. Still, all those notwithstanding, I think this is the best we can get until there's language support for interface functions. Thoughts?

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• Problem measuring N times the execution time of a code block

  - by Nazgulled

  EDIT: I just found my problem after writing this long post explaining every little detail... If someone can give me a good answer on what I'm doing wrong and how can I get the execution time in seconds (using a float with 5 decimal places or so), I'll mark that as accepted. Hint: The problem was on how I interpreted the clock_getttime() man page. Hi, Let's say I have a function named myOperation that I need to measure the execution time of. To measure it, I'm using clock_gettime() as it was recommend here in one of the comments. My teacher recommends us to measure it N times so we can get an average, standard deviation and median for the final report. He also recommends us to execute myOperation M times instead of just one. If myOperation is a very fast operation, measuring it M times allow us to get a sense of the "real time" it takes; cause the clock being used might not have the required precision to measure such operation. So, execution myOperation only one time or M times really depends if the operation itself takes long enough for the clock precision we are using. I'm having trouble dealing with that M times execution. Increasing M decreases (a lot) the final average value. Which doesn't make sense to me. It's like this, on average you take 3 to 5 seconds to travel from point A to B. But then you go from A to B and back to A 5 times (which makes it 10 times, cause A to B is the same as B to A) and you measure that. Than you divide by 10, the average you get is supposed to be the same average you take traveling from point A to B, which is 3 to 5 seconds. This is what I want my code to do, but it's not working. If I keep increasing the number of times I go from A to B and back A, the average will be lower and lower each time, it makes no sense to me. Enough theory, here's my code: #include <stdio.h> #include <time.h> #define MEASUREMENTS 1 #define OPERATIONS 1 typedef struct timespec TimeClock; TimeClock diffTimeClock(TimeClock start, TimeClock end) { TimeClock aux; if((end.tv_nsec - start.tv_nsec) < 0) { aux.tv_sec = end.tv_sec - start.tv_sec - 1; aux.tv_nsec = 1E9 + end.tv_nsec - start.tv_nsec; } else { aux.tv_sec = end.tv_sec - start.tv_sec; aux.tv_nsec = end.tv_nsec - start.tv_nsec; } return aux; } int main(void) { TimeClock sTime, eTime, dTime; int i, j; for(i = 0; i < MEASUREMENTS; i++) { printf(" » MEASURE %02d\n", i+1); clock_gettime(CLOCK_REALTIME, &sTime); for(j = 0; j < OPERATIONS; j++) { myOperation(); } clock_gettime(CLOCK_REALTIME, &eTime); dTime = diffTimeClock(sTime, eTime); printf(" - NSEC (TOTAL): %ld\n", dTime.tv_nsec); printf(" - NSEC (OP): %ld\n\n", dTime.tv_nsec / OPERATIONS); } return 0; } Notes: The above diffTimeClock function is from this blog post. I replaced my real operation with myOperation() because it doesn't make any sense to post my real functions as I would have to post long blocks of code, you can easily code a myOperation() with whatever you like to compile the code if you wish. As you can see, OPERATIONS = 1 and the results are: » MEASURE 01 - NSEC (TOTAL): 27456580 - NSEC (OP): 27456580 For OPERATIONS = 100 the results are: » MEASURE 01 - NSEC (TOTAL): 218929736 - NSEC (OP): 2189297 For OPERATIONS = 1000 the results are: » MEASURE 01 - NSEC (TOTAL): 862834890 - NSEC (OP): 862834 For OPERATIONS = 10000 the results are: » MEASURE 01 - NSEC (TOTAL): 574133641 - NSEC (OP): 57413 Now, I'm not a math wiz, far from it actually, but this doesn't make any sense to me whatsoever. I've already talked about this with a friend that's on this project with me and he also can't understand the differences. I don't understand why the value is getting lower and lower when I increase OPERATIONS. The operation itself should take the same time (on average of course, not the exact same time), no matter how many times I execute it. You could tell me that that actually depends on the operation itself, the data being read and that some data could already be in the cache and bla bla, but I don't think that's the problem. In my case, myOperation is reading 5000 lines of text from an CSV file, separating the values by ; and inserting those values into a data structure. For each iteration, I'm destroying the data structure and initializing it again. Now that I think of it, I also that think that there's a problem measuring time with clock_gettime(), maybe I'm not using it right. I mean, look at the last example, where OPERATIONS = 10000. The total time it took was 574133641ns, which would be roughly 0,5s; that's impossible, it took a couple of minutes as I couldn't stand looking at the screen waiting and went to eat something.

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• Different behavior for REF CURSOR between Oracle 10g and 11g when unique index present?

  - by wweicker

  Description I have an Oracle stored procedure that has been running for 7 or so years both locally on development instances and on multiple client test and production instances running Oracle 8, then 9, then 10, and recently 11. It has worked consistently until the upgrade to Oracle 11g. Basically, the procedure opens a reference cursor, updates a table then completes. In 10g the cursor will contain the expected results but in 11g the cursor will be empty. No DML or DDL changed after the upgrade to 11g. This behavior is consistent on every 10g or 11g instance I've tried (10.2.0.3, 10.2.0.4, 11.1.0.7, 11.2.0.1 - all running on Windows). The specific code is much more complicated but to explain the issue in somewhat realistic overview: I have some data in a header table and a bunch of child tables that will be output to PDF. The header table has a boolean (NUMBER(1) where 0 is false and 1 is true) column indicating whether that data has been processed yet. The view is limited to only show rows in that have not been processed (the view also joins on some other tables, makes some inline queries and function calls, etc). So at the time when the cursor is opened, the view shows one or more rows, then after the cursor is opened an update statement runs to flip the flag in the header table, a commit is issued, then the procedure completes. On 10g, the cursor opens, it contains the row, then the update statement flips the flag and running the procedure a second time would yield no data. On 11g, the cursor never contains the row, it's as if the cursor does not open until after the update statement runs. I'm concerned that something may have changed in 11g (hopefully a setting that can be configured) that might affect other procedures and other applications. What I'd like to know is whether anyone knows why the behavior is different between the two database versions and whether the issue can be resolved without code changes. Update 1: I managed to track the issue down to a unique constraint. It seems that when the unique constraint is present in 11g the issue is reproducible 100% of the time regardless of whether I'm running the real world code against the actual objects or the following simple example. Update 2: I was able to completely eliminate the view from the equation. I have updated the simple example to show the problem exists even when querying directly against the table. Simple Example CREATE TABLE tbl1 ( col1 VARCHAR2(10), col2 NUMBER(1) ); INSERT INTO tbl1 (col1, col2) VALUES ('TEST1', 0); /* View is no longer required to demonstrate the problem CREATE OR REPLACE VIEW vw1 (col1, col2) AS SELECT col1, col2 FROM tbl1 WHERE col2 = 0; */ CREATE OR REPLACE PACKAGE pkg1 AS TYPE refWEB_CURSOR IS REF CURSOR; PROCEDURE proc1 (crs OUT refWEB_CURSOR); END pkg1; CREATE OR REPLACE PACKAGE BODY pkg1 IS PROCEDURE proc1 (crs OUT refWEB_CURSOR) IS BEGIN OPEN crs FOR SELECT col1 FROM tbl1 WHERE col1 = 'TEST1' AND col2 = 0; UPDATE tbl1 SET col2 = 1 WHERE col1 = 'TEST1'; COMMIT; END proc1; END pkg1; Anonymous Block Demo DECLARE crs1 pkg1.refWEB_CURSOR; TYPE rectype1 IS RECORD ( col1 vw1.col1%TYPE ); rec1 rectype1; BEGIN pkg1.proc1 ( crs1 ); DBMS_OUTPUT.PUT_LINE('begin first test'); LOOP FETCH crs1 INTO rec1; EXIT WHEN crs1%NOTFOUND; DBMS_OUTPUT.PUT_LINE(rec1.col1); END LOOP; DBMS_OUTPUT.PUT_LINE('end first test'); END; /* After creating this index, the problem is seen */ CREATE UNIQUE INDEX unique_col1 ON tbl1 (col1); /* Reset data to initial values */ TRUNCATE TABLE tbl1; INSERT INTO tbl1 (col1, col2) VALUES ('TEST1', 0); DECLARE crs1 pkg1.refWEB_CURSOR; TYPE rectype1 IS RECORD ( col1 vw1.col1%TYPE ); rec1 rectype1; BEGIN pkg1.proc1 ( crs1 ); DBMS_OUTPUT.PUT_LINE('begin second test'); LOOP FETCH crs1 INTO rec1; EXIT WHEN crs1%NOTFOUND; DBMS_OUTPUT.PUT_LINE(rec1.col1); END LOOP; DBMS_OUTPUT.PUT_LINE('end second test'); END; Example of what the output on 10g would be:   begin first test   TEST1   end first test   begin second test   TEST1   end second test Example of what the output on 11g would be:   begin first test   TEST1   end first test   begin second test   end second test Clarification I can't remove the COMMIT because in the real world scenario the procedure is called from a web application. When the data provider on the front end calls the procedure it will issue an implicit COMMIT when disconnecting from the database anyways. So if I remove the COMMIT in the procedure then yes, the anonymous block demo would work but the real world scenario would not because the COMMIT would still happen. Question Why is 11g behaving differently? Is there anything I can do other than re-write the code?

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• Failed to load Cairo

  - by Ruben

  We're running a Ubuntu Server VM with OpenCPU (that's an API for R). Unfortunately we're unable to get the Cairo R package to play, the error message (from within R) is as follows: unable to load shared object '/usr/lib/R/library/grDevices/libs//cairo.so': /usr/local/lib/libgmodule-2.0.so.0: undefined symbol: g_rec_mutex_lock 2: In png() : failed to load cairo DLL We've tried purging and reinstalling cairo and libcairo and we both tried building the Cairo R package from source as well as using a precompiled version from Michael Rutter's ppas (all seems to work without errors). Unfortunately none of us are real Ubuntu natives and thus we probably did some pretty amateur debugging. Any push in the right direction would be very appreciated. For example, we couldn't figure out how to reinstall whatever libgmodule refers to.

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• Windows 7 Phone Database Rapid Repository – V2.0 Beta Released

  - by SeanMcAlinden

  Hi All, A V2.0 beta has been released for the Windows 7 Phone database Rapid Repository, this can be downloaded at the following: http://rapidrepository.codeplex.com/ Along with the new View feature which greatly enhances querying and performance, various bugs have been fixed including a more serious bug with the caching that caused the GetAll() method to sometimes return inconsistent results (I’m a little bit embarrased by this bug). If you are currently using V1.0 in development, I would recommend swapping in the beta immediately. A full release will be available very shortly, I just need a few more days of testing and some input from other users/testers.   *Breaking Changes* The only real change is the RapidContext has moved under the main RapidRepository namespace. Various internal methods have been actually made ‘internal’ and replaced with a more friendly API (I imagine not many users will notice this change). Hope you like it Kind Regards, Sean McAlinden

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• Complete Guide to Networking Windows 7 with XP and Vista

  - by Mysticgeek

  Since there are three versions of Windows out in the field these days, chances are you need to share data between them. Today we show how to get each version to be share files and printers with one another. In a perfect world, getting your computers with different Microsoft operating systems to network would be as easy as clicking a button. With the Windows 7 Homegroup feature, it’s almost that easy. However, getting all three of them to communicate with each other can be a bit of a challenge. Today we’ve put together a guide that will help you share files and printers in whatever scenario of the three versions you might encounter on your home network. Sharing Between Windows 7 and XP The most common scenario you’re probably going to run into is sharing between Windows 7 and XP.  Essentially you’ll want to make sure both machines are part of the same workgroup, set up the correct sharing settings, and making sure network discovery is enabled on Windows 7. The biggest problem you may run into is finding the correct printer drivers for both versions of Windows. Share Files and Printers Between Windows 7 & XP  Map a Network Drive Another method of sharing data between XP and Windows 7 is mapping a network drive. If you don’t need to share a printer and only want to share a drive, then you can just map an XP drive to Windows 7. Although it might sound complicated, the process is not bad. The trickiest part is making sure you add the appropriate local user. This will allow you to share the contents of an XP drive to your Windows 7 computer. Map a Network Drive from XP to Windows 7 Sharing between Vista and Windows 7 Another scenario you might run into is having to share files and printers between a Vista and Windows 7 machine. The process is a bit easier than sharing between XP and Windows 7, but takes a bit of work. The Homegroup feature isn’t compatible with Vista, so we need to go through a few different steps. Depending on what your printer is, sharing it should be easier as Vista and Windows 7 do a much better job of automatically locating the drivers. How to Share Files and Printers Between Windows 7 and Vista Sharing between Vista and XP When Windows Vista came out, hardware requirements were intensive, drivers weren’t ready, and sharing between them was complicated due to the new Vista structure. The sharing process is pretty straight-forward if you’re not using password protection…as you just need to drop what you want to share into the Vista Public folder. On the other hand, sharing with password protection becomes a bit more difficult. Basically you need to add a user and set up sharing on the XP machine. But once again, we have a complete tutorial for that situation. Share Files and Folders Between Vista and XP Machines Sharing Between Windows 7 with Homegroup If you have one or more Windows 7 machine, sharing files and devices becomes extremely easy with the Homegroup feature. It’s as simple as creating a Homegroup on on machine then joining the other to it. It allows you to stream media, control what data is shared, and can also be password protected. If you don’t want to make your Windows 7 machines part of the same Homegroup, you can still share files through the Public Folder, and setup a printer to be shared as well.   Use the Homegroup Feature in Windows 7 to Share Printers and Files Create a Homegroup & Join a New Computer To It Change which Files are Shared in a Homegroup Windows Home Server If you want an ultimate setup that creates a centralized location to share files between all systems on your home network, regardless of the operating system, then set up a Windows Home Server. It allows you to centralize your important documents and digital media files on one box and provides easy access to data and the ability to stream media to other machines on your network. Not only that, but it provides easy backup of all your machines to the server, in case disaster strikes. How to Install and Setup Windows Home Server How to Manage Shared Folders on Windows Home Server Conclusion The biggest annoyance is dealing with printers that have a different set of drivers for each OS. There is no real easy way to solve this problem. Our best advice is to try to connect it to one machine, and if the drivers won’t work, hook it up to the other computer and see if that works. Each printer manufacturer is different, and Windows doesn’t always automatically install the correct drivers for the device. We hope this guide helps you share your data between whichever Microsoft OS scenario you might run into! Here are some other articles that will help you accomplish your home networking needs: Share a Printer on a Home Network from Vista or XP to Windows 7 How to Share a Folder the XP Way in Windows Vista Similar Articles Productive Geek Tips Delete Wrong AutoComplete Entries in Windows Vista MailSvchost Viewer Shows Exactly What Each svchost.exe Instance is DoingFixing "BOOTMGR is missing" Error While Trying to Boot Windows VistaShow Hidden Files and Folders in Windows 7 or VistaAdd Color Coding to Windows 7 Media Center Program Guide TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Icelandic Volcano Webcams Open Multiple Links At One Go NachoFoto Searches Images in Real-time Office 2010 Product Guides Google Maps Place marks – Pizza, Guns or Strip Clubs Monitor Applications With Kiwi

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• SQL SERVER – Quick Look at SQL Server Configuration for Performance Indications

  - by pinaldave

  Earlier I wrote SQL SERVER – Beginning SQL Server: One Step at a Time – SQL Server Magazine. That was the first article on the series of my real world experience of Performance Tuning experience. I have written second part the same series over here. Read second part over here: Quick Look at SQL Server Configuration for Performance Indications. In this second part I talk about two types of my clients. 1) Those who want instant results 2) Those who want the right results It is really fun to work with both the clients. I talk about various configuration options which I look at when I try to give very early opinion about SQL Server Performance. There are various eight configurations, I give quick look and start talking about performance. Head over to original article over here: Quick Look at SQL Server Configuration for Performance Indications. Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Top things web developers should know about the Visual Studio 2013 release

  - by Jon Galloway

  ASP.NET and Web Tools for Visual Studio 2013 Release NotesASP.NET and Web Tools for Visual Studio 2013 Release NotesSummary for lazy readers: Visual Studio 2013 is now available for download on the Visual Studio site and on MSDN subscriber downloads) Visual Studio 2013 installs side by side with Visual Studio 2012 and supports round-tripping between Visual Studio versions, so you can try it out without committing to a switch Visual Studio 2013 ships with the new version of ASP.NET, which includes ASP.NET MVC 5, ASP.NET Web API 2, Razor 3, Entity Framework 6 and SignalR 2.0 The new releases ASP.NET focuses on One ASP.NET, so core features and web tools work the same across the platform (e.g. adding ASP.NET MVC controllers to a Web Forms application) New core features include new templates based on Bootstrap, a new scaffolding system, and a new identity system Visual Studio 2013 is an incredible editor for web files, including HTML, CSS, JavaScript, Markdown, LESS, Coffeescript, Handlebars, Angular, Ember, Knockdown, etc. Top links: Visual Studio 2013 content on the ASP.NET site are in the standard new releases area: http://www.asp.net/vnext ASP.NET and Web Tools for Visual Studio 2013 Release Notes Short intro videos on the new Visual Studio web editor features from Scott Hanselman and Mads Kristensen Announcing release of ASP.NET and Web Tools for Visual Studio 2013 post on the official .NET Web Development and Tools Blog Scott Guthrie's post: Announcing the Release of Visual Studio 2013 and Great Improvements to ASP.NET and Entity Framework Okay, for those of you who are still with me, let's dig in a bit. Quick web dev notes on downloading and installing Visual Studio 2013 I found Visual Studio 2013 to be a pretty fast install. According to Brian Harry's release post, installing over pre-release versions of Visual Studio is supported.  I've installed the release version over pre-release versions, and it worked fine. If you're only going to be doing web development, you can speed up the install if you just select Web Developer tools. Of course, as a good Microsoft employee, I'll mention that you might also want to install some of those other features, like the Store apps for Windows 8 and the Windows Phone 8.0 SDK, but they do download and install a lot of other stuff (e.g. the Windows Phone SDK sets up Hyper-V and downloads several GB's of VM's). So if you're planning just to do web development for now, you can pick just the Web Developer Tools and install the other stuff later. If you've got a fast internet connection, I recommend using the web installer instead of downloading the ISO. The ISO includes all the features, whereas the web installer just downloads what you're installing. Visual Studio 2013 development settings and color theme When you start up Visual Studio, it'll prompt you to pick some defaults. These are totally up to you -whatever suits your development style - and you can change them later. As I said, these are completely up to you. I recommend either the Web Development or Web Development (Code Only) settings. The only real difference is that Code Only hides the toolbars, and you can switch between them using Tools / Import and Export Settings / Reset. Web Development settings Web Development (code only) settings Usually I've just gone with Web Development (code only) in the past because I just want to focus on the code, although the Standard toolbar does make it easier to switch default web browsers. More on that later. Color theme Sigh. Okay, everyone's got their favorite colors. I alternate between Light and Dark depending on my mood, and I personally like how the low contrast on the window chrome in those themes puts the emphasis on my code rather than the tabs and toolbars. I know some people got pretty worked up over that, though, and wanted the blue theme back. I personally don't like it - it reminds me of ancient versions of Visual Studio that I don't want to think about anymore. So here's the thing: if you install Visual Studio Ultimate, it defaults to Blue. The other versions default to Light. If you use Blue, I won't criticize you - out loud, that is. You can change themes really easily - either Tools / Options / Environment / General, or the smart way: ctrl+q for quick launch, then type Theme and hit enter. Signing in During the first run, you'll be prompted to sign in. You don't have to - you can click the "Not now, maybe later" link at the bottom of that dialog. I recommend signing in, though. It's not hooked in with licensing or tracking the kind of code you write to sell you components. It is doing good things, like  syncing your Visual Studio settings between computers. More about that here. So, you don't have to, but I sure do. Overview of shiny new things in ASP.NET land There are a lot of good new things in ASP.NET. I'll list some of my favorite here, but you can read more on the ASP.NET site. One ASP.NET You've heard us talk about this for a while. The idea is that options are good, but choice can be a burden. When you start a new ASP.NET project, why should you have to make a tough decision - with long-term consequences - about how your application will work? If you want to use ASP.NET Web Forms, but have the option of adding in ASP.NET MVC later, why should that be hard? It's all ASP.NET, right? Ideally, you'd just decide that you want to use ASP.NET to build sites and services, and you could use the appropriate tools (the green blocks below) as you needed them. So, here it is. When you create a new ASP.NET application, you just create an ASP.NET application. Next, you can pick from some templates to get you started... but these are different. They're not "painful decision" templates, they're just some starting pieces. And, most importantly, you can mix and match. I can pick a "mostly" Web Forms template, but include MVC and Web API folders and core references. If you've tried to mix and match in the past, you're probably aware that it was possible, but not pleasant. ASP.NET MVC project files contained special project type GUIDs, so you'd only get controller scaffolding support in a Web Forms project if you manually edited the csproj file. Features in one stack didn't work in others. Project templates were painful choices. That's no longer the case. Hooray! I just did a demo in a presentation last week where I created a new Web Forms + MVC + Web API site, built a model, scaffolded MVC and Web API controllers with EF Code First, add data in the MVC view, viewed it in Web API, then added a GridView to the Web Forms Default.aspx page and bound it to the Model. In about 5 minutes. Sure, it's a simple example, but it's great to be able to share code and features across the whole ASP.NET family. Authentication In the past, authentication was built into the templates. So, for instance, there was an ASP.NET MVC 4 Intranet Project template which created a new ASP.NET MVC 4 application that was preconfigured for Windows Authentication. All of that authentication stuff was built into each template, so they varied between the stacks, and you couldn't reuse them. You didn't see a lot of changes to the authentication options, since they required big changes to a bunch of project templates. Now, the new project dialog includes a common authentication experience. When you hit the Change Authentication button, you get some common options that work the same way regardless of the template or reference settings you've made. These options work on all ASP.NET frameworks, and all hosting environments (IIS, IIS Express, or OWIN for self-host) The default is Individual User Accounts: This is the standard "create a local account, using username / password or OAuth" thing; however, it's all built on the new Identity system. More on that in a second. The one setting that has some configuration to it is Organizational Accounts, which lets you configure authentication using Active Directory, Windows Azure Active Directory, or Office 365. Identity There's a new identity system. We've taken the best parts of the previous ASP.NET Membership and Simple Identity systems, rolled in a lot of feedback and made big enhancements to support important developer concerns like unit testing and extensiblity. I've written long posts about ASP.NET identity, and I'll do it again. Soon. This is not that post. The short version is that I think we've finally got just the right Identity system. Some of my favorite features: There are simple, sensible defaults that work well - you can File / New / Run / Register / Login, and everything works. It supports standard username / password as well as external authentication (OAuth, etc.). It's easy to customize without having to re-implement an entire provider. It's built using pluggable pieces, rather than one large monolithic system. It's built using interfaces like IUser and IRole that allow for unit testing, dependency injection, etc. You can easily add user profile data (e.g. URL, twitter handle, birthday). You just add properties to your ApplicationUser model and they'll automatically be persisted. Complete control over how the identity data is persisted. By default, everything works with Entity Framework Code First, but it's built to support changes from small (modify the schema) to big (use another ORM, store your data in a document database or in the cloud or in XML or in the EXIF data of your desktop background or whatever). It's configured via OWIN. More on OWIN and Katana later, but the fact that it's built using OWIN means it's portable. You can find out more in the Authentication and Identity section of the ASP.NET site (and lots more content will be going up there soon). New Bootstrap based project templates The new project templates are built using Bootstrap 3. Bootstrap (formerly Twitter Bootstrap) is a front-end framework that brings a lot of nice benefits: It's responsive, so your projects will automatically scale to device width using CSS media queries. For example, menus are full size on a desktop browser, but on narrower screens you automatically get a mobile-friendly menu. The built-in Bootstrap styles make your standard page elements (headers, footers, buttons, form inputs, tables etc.) look nice and modern. Bootstrap is themeable, so you can reskin your whole site by dropping in a new Bootstrap theme. Since Bootstrap is pretty popular across the web development community, this gives you a large and rapidly growing variety of templates (free and paid) to choose from. Bootstrap also includes a lot of very useful things: components (like progress bars and badges), useful glyphicons, and some jQuery plugins for tooltips, dropdowns, carousels, etc.). Here's a look at how the responsive part works. When the page is full screen, the menu and header are optimized for a wide screen display: When I shrink the page down (this is all based on page width, not useragent sniffing) the menu turns into a nice mobile-friendly dropdown: For a quick example, I grabbed a new free theme off bootswatch.com. For simple themes, you just need to download the boostrap.css file and replace the /content/bootstrap.css file in your project. Now when I refresh the page, I've got a new theme: Scaffolding The big change in scaffolding is that it's one system that works across ASP.NET. You can create a new Empty Web project or Web Forms project and you'll get the Scaffold context menus. For release, we've got MVC 5 and Web API 2 controllers. We had a preview of Web Forms scaffolding in the preview releases, but they weren't fully baked for RTM. Look for them in a future update, expected pretty soon. This scaffolding system wasn't just changed to work across the ASP.NET frameworks, it's also built to enable future extensibility. That's not in this release, but should also hopefully be out soon. Project Readme page This is a small thing, but I really like it. When you create a new project, you get a Project_Readme.html page that's added to the root of your project and opens in the Visual Studio built-in browser. I love it. A long time ago, when you created a new project we just dumped it on you and left you scratching your head about what to do next. Not ideal. Then we started adding a bunch of Getting Started information to the new project templates. That told you what to do next, but you had to delete all of that stuff out of your website. It doesn't belong there. Not ideal. This is a simple HTML file that's not integrated into your project code at all. You can delete it if you want. But, it shows a lot of helpful links that are current for the project you just created. In the future, if we add new wacky project types, they can create readme docs with specific information on how to do appropriately wacky things. Side note: I really like that they used the internal browser in Visual Studio to show this content rather than popping open an HTML page in the default browser. I hate that. It's annoying. If you're doing that, I hope you'll stop. What if some unnamed person has 40 or 90 tabs saved in their browser session? When you pop open your "Thanks for installing my Visual Studio extension!" page, all eleventy billion tabs start up and I wish I'd never installed your thing. Be like these guys and pop stuff Visual Studio specific HTML docs in the Visual Studio browser. ASP.NET MVC 5 The biggest change with ASP.NET MVC 5 is that it's no longer a separate project type. It integrates well with the rest of ASP.NET. In addition to that and the other common features we've already looked at (Bootstrap templates, Identity, authentication), here's what's new for ASP.NET MVC. Attribute routing ASP.NET MVC now supports attribute routing, thanks to a contribution by Tim McCall, the author of http://attributerouting.net. With attribute routing you can specify your routes by annotating your actions and controllers. This supports some pretty complex, customized routing scenarios, and it allows you to keep your route information right with your controller actions if you'd like. Here's a controller that includes an action whose method name is Hiding, but I've used AttributeRouting to configure it to /spaghetti/with-nesting/where-is-waldo public class SampleController : Controller { [Route("spaghetti/with-nesting/where-is-waldo")] public string Hiding() { return "You found me!"; } } I enable that in my RouteConfig.cs, and I can use that in conjunction with my other MVC routes like this: public class RouteConfig { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapMvcAttributeRoutes(); routes.MapRoute( name: "Default", url: "{controller}/{action}/{id}", defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional } ); } } You can read more about Attribute Routing in ASP.NET MVC 5 here. Filter enhancements There are two new additions to filters: Authentication Filters and Filter Overrides. Authentication filters are a new kind of filter in ASP.NET MVC that run prior to authorization filters in the ASP.NET MVC pipeline and allow you to specify authentication logic per-action, per-controller, or globally for all controllers. Authentication filters process credentials in the request and provide a corresponding principal. Authentication filters can also add authentication challenges in response to unauthorized requests. Override filters let you change which filters apply to a given action method or controller. Override filters specify a set of filter types that should not be run for a given scope (action or controller). This allows you to configure filters that apply globally but then exclude certain global filters from applying to specific actions or controllers. ASP.NET Web API 2 ASP.NET Web API 2 includes a lot of new features. Attribute Routing ASP.NET Web API supports the same attribute routing system that's in ASP.NET MVC 5. You can read more about the Attribute Routing features in Web API in this article. OAuth 2.0 ASP.NET Web API picks up OAuth 2.0 support, using security middleware running on OWIN (discussed below). This is great for features like authenticated Single Page Applications. OData Improvements ASP.NET Web API now has full OData support. That required adding in some of the most powerful operators: $select, $expand, $batch and $value. You can read more about OData operator support in this article by Mike Wasson. Lots more There's a huge list of other features, including CORS (cross-origin request sharing), IHttpActionResult, IHttpRequestContext, and more. I think the best overview is in the release notes. OWIN and Katana I've written about OWIN and Katana recently. I'm a big fan. OWIN is the Open Web Interfaces for .NET. It's a spec, like HTML or HTTP, so you can't install OWIN. The benefit of OWIN is that it's a community specification, so anyone who implements it can plug into the ASP.NET stack, either as middleware or as a host. Katana is the Microsoft implementation of OWIN. It leverages OWIN to wire up things like authentication, handlers, modules, IIS hosting, etc., so ASP.NET can host OWIN components and Katana components can run in someone else's OWIN implementation. Howard Dierking just wrote a cool article in MSDN magazine describing Katana in depth: Getting Started with the Katana Project. He had an interesting example showing an OWIN based pipeline which leveraged SignalR, ASP.NET Web API and NancyFx components in the same stack. If this kind of thing makes sense to you, that's great. If it doesn't, don't worry, but keep an eye on it. You're going to see some cool things happen as a result of ASP.NET becoming more and more pluggable. Visual Studio Web Tools Okay, this stuff's just crazy. Visual Studio has been adding some nice web dev features over the past few years, but they've really cranked it up for this release. Visual Studio is by far my favorite code editor for all web files: CSS, HTML, JavaScript, and lots of popular libraries. Stop thinking of Visual Studio as a big editor that you only use to write back-end code. Stop editing HTML and CSS in Notepad (or Sublime, Notepad++, etc.). Visual Studio starts up in under 2 seconds on a modern computer with an SSD. Misspelling HTML attributes or your CSS classes or jQuery or Angular syntax is stupid. It doesn't make you a better developer, it makes you a silly person who wastes time. Browser Link Browser Link is a real-time, two-way connection between Visual Studio and all connected browsers. It's only attached when you're running locally, in debug, but it applies to any and all connected browser, including emulators. You may have seen demos that showed the browsers refreshing based on changes in the editor, and I'll agree that's pretty cool. But it's really just the start. It's a two-way connection, and it's built for extensiblity. That means you can write extensions that push information from your running application (in IE, Chrome, a mobile emulator, etc.) back to Visual Studio. Mads and team have showed off some demonstrations where they enabled edit mode in the browser which updated the source HTML back on the browser. It's also possible to look at how the rendered HTML performs, check for compatibility issues, watch for unused CSS classes, the sky's the limit. New HTML editor The previous HTML editor had a lot of old code that didn't allow for improvements. The team rewrote the HTML editor to take advantage of the new(ish) extensibility features in Visual Studio, which then allowed them to add in all kinds of features - things like CSS Class and ID IntelliSense (so you type style="" and get a list of classes and ID's for your project), smart indent based on how your document is formatted, JavaScript reference auto-sync, etc. Here's a 3 minute tour from Mads Kristensen. The previous HTML editor had a lot of old code that didn't allow for improvements. The team rewrote the HTML editor to take advantage of the new(ish) extensibility features in Visual Studio, which then allowed them to add in all kinds of features - things like CSS Class and ID IntelliSense (so you type style="" and get a list of classes and ID's for your project), smart indent based on how your document is formatted, JavaScript reference auto-sync, etc. Lots more Visual Studio web dev features That's just a sampling - there's a ton of great features for JavaScript editing, CSS editing, publishing, and Page Inspector (which shows real-time rendering of your page inside Visual Studio). Here are some more short videos showing those features. Lots, lots more Okay, that's just a summary, and it's still quite a bit. Head on over to http://asp.net/vnext for more information, and download Visual Studio 2013 now to get started!

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• CodePlex Daily Summary for Friday, February 19, 2010

  CodePlex Daily Summary for Friday, February 19, 2010New ProjectsApplication Management Library: Application Management makes your application life easier. It will automatic do memory management, handle and log unhandled exceptions, profiling y...Audio Service - Play Wave Files From Windows Service: This is a windows service that Check a registry key, when the key is updated with a new wave file path the service plays the wave file.Aviamodels: 3d drawing AviamodelsControl of payment proofs program for Greek citizens: This is a program that is used for Greek citizens who want to keep track of their payment proofs.Cover Creator: Cover Creator gives you the possibility to create and print CD covers. Content of CD is taken from http://www.freedb.org/ or can be added/modyfied ...DevBoard: DevBoard is a webbased scrum tool that helps developers/team get a clear overview of the project progress. It's developed in C# and silverlight.Flex AdventureWorks: The is mostly a skunk-works application to help me get acclimated to CodePlex. The long term goal is to integrate a Flex UI with the AdventureWor...GRE Wordlist: An intuitive and customizable word list for GRE aspirants. Developed in Java using a word list similar to Barron's.Indexer: A desktop file Index and Search tool which allows you to choose a list of folders to index, and then search on later. It is based on Lucene.net an...Project Management Office (PMO) for SharePoint: Sample web part for the Code Mastery event in Boston, February 11, 2010.Restart SQL Audit Policy and Job: Resolve SQL 2008 Audit Network Connectivity Issue.Rounded Corners / DIV Container: The RoundedDiv round corners container is a skin-able, CSS compliant UI control. Select which corners should be rounded, collapse and expand the c...Silverlight Google Search Application: The Silverlight Google Search Application uses Google Search API and behaves like Internet Search Application with option to preview desired page i...Weather Forecast Control: MyWeather forecast control pulls up to date weather forecast information from The Weather Channel for your website.New ReleasesApplication Management Library: ApplicationManagement v1.0: First ReleaseAudio Service - Play Wave Files From Windows Service: Audio Service v1.0: This is a working version of the Audio Service. Please use as you need to.AutoMapper: 1.0.1 for Silverlight 3.0 Alpha: AutoMapper for Silverlight 3.0. Features not supported: IDataReader mapping IListSource mapping All other features are supported.Buzz Dot Net: Buzz Dot Net v.1.10219: Buzz Dot Net Library (Parser & Objects) + WPF Example (using MVVM & Threading)Canvas VSDOC Intellisense: V 1.0.0.0a: This release contains two JavaScript files: canvas-utils.js (can be referenced in both runtime and development environment) canvas-vsdoc.js (must ...Control of payment proofs program for Greek citizens: Payment Proofs: source codeCourier: Beta 2: Added Rx Framework support and re-factored how message registration and un-registration works Blog post explaining the updates and re-factoring c...Cover Creator: Initial release: This is initial stable release. For now only in Polish language.Employee Scheduler: Employee Scheduler 2.2: Small Bug found. Small total hour calculation bug. See http://employeescheduler.codeplex.com/WorkItem/View.aspx?WorkItemId=6059 Extract the files...EnhSim: Release v1.9.7.1: Release v1.9.7.1Implemented Dislodged Foreign Object trinket Whispering Fanged Skull now also procs off Flame shock dots You can toggle bloodlust o...Extend SmallBasic: Teaching Extensions v.007: added SimpleSquareTest added Tortoise.Approve() for virtual proctor how to use virtual proctor: change the path in the proctor.txt file (located i...FolderSize: FolderSize.Win32.1.0.1.0: FolderSize.Win32.1.0.1.0 A simple utility intended to be used to scan harddrives for the folders that take most place and display this to the user...GLB Virtual Player Builder: v0.4.0 Beta: Allows for user to import and use archetypes for building players. The archetypes are contained in the file "archetypes.xml". This file is editab...Google Map WebPart from SharePoint List: GMap Stable Release: GMap Stable ReleaseHenge3D Physics Library for XNA: Henge3D Source (2010-02 R2): Fixed a build error related to an assembly attribute in XBOX 360 builds. Tweaked the controls in the sample when targeting the 360. Reduced the...Indexer: Beta Release 1: Just the initial/rough cut.NukeCS: NukeCS 5.2.3 Source Code: update version to 5.2.3ODOS: ODOS STABLE 1.5.0: Thank you for your patience while we develop this version. Not that much has been added, though. Just doing some sub-conscious stuff to make life...PoshBoard: PoshBoard 3.0 Beta 1: Welcome to the first beta release of PoshBoard 3.0 ! IMPORTANT WARNING : this release is absolutly not feature complete and is error-prone. Okay, ...Restart SQL Audit Policy and Job: Restart SQL 2008 Audit Policy and Job: This folder contains three pieces of source code: Server Audit Status (Started).xml - Import this on-schedule policy into your server's Policy-Ba...SAL- Self Artificial Learning: Artificial Learning 2AQV Working Proof Of Concept: This is the Simulation proof of concept version that comes after the 1aq version. AQ stands for Anwering Questions.SharePoint 2010 Word Automation: SP 2010 Word Automation - Workflow Actions 1.1: This release includes two new custom workflow activities for SharePoint designer Convert Folder Convert Library More information about these new...SharePoint Outlook Connector: Version 1.0.1.1: Exception Logging has been improved.Sharpy: Sharpy 1.2 Alpha: This is the third Sharpy release. A change has been made to allow overriding the master page from the controller. The release contains the single ...Silverlight Google Search Application: SL Google Search App Alpha: This is just a first alpha version of the application, as it looks like when I uploaded it to CodePlex. The application works, requires Silverlight...Starter Kit Mytrip.Mvc.Entity: Mytrip.Mvc.Entity 1.0 RC: EF Membership UserManager FileManager Localization Captcha ClientValidation Theme CrossBrowser VS 2010 RC MVC 2 RC db MSSQL2008thinktecture WSCF.blue: WSCF.blue V1 Update (1.0.6): This release is an update for WSCF.blue V1. Below are the bug fixes made since the V1.0.5 release: The data contract type filter was not including...TS3QueryLib.Net: TS3QueryLib.Net Version 0.18.13.0: Changelog Added overloads to all methods of QueryRunenr class handling permission tasks to allow passing of permission name instead of permissionid...Umbraco CMS: Umbraco 4.1 Beta 2: This is the second beta of Umbraco 4.1. Umbraco 4.1 is more advanced than ever, yet faster, lighter and simpler to use than ever. We, on behalf of...VCC: Latest build, v2.1.30218.0: Automatic drop of latest buildZack's Fiasco - Code Generated DAL: v1.2.4: Enhancements: SQL Server CRUD Stored Procedures added option for USE <db> added option to create or not create INSERT sprocs added option to cr...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)Image Resizer Powertoy Clone for WindowsASP.NETMicrosoft SQL Server Community & SamplesDotNetNuke® Community EditionMost Active ProjectsRawrSharpyDinnerNow.netBlogEngine.NETjQuery Library for SharePoint Web ServicesNB_Store - Free DotNetNuke Ecommerce Catalog Modulepatterns & practices – Enterprise LibraryPHPExcelFacebook Developer ToolkitFluent Ribbon Control Suite

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• Parallelism in .NET – Part 13, Introducing the Task class

  - by Reed

  Once we’ve used a task-based decomposition to decompose a problem, we need a clean abstraction usable to implement the resulting decomposition.  Given that task decomposition is founded upon defining discrete tasks, .NET 4 has introduced a new API for dealing with task related issues, the aptly named Task class. The Task class is a wrapper for a delegate representing a single, discrete task within your decomposition.  We will go into various methods of construction for tasks later, but, when reduced to its fundamentals, an instance of a Task is nothing more than a wrapper around a delegate with some utility functionality added.  In order to fully understand the Task class within the new Task Parallel Library, it is important to realize that a task really is just a delegate – nothing more.  In particular, note that I never mentioned threading or parallelism in my description of a Task.  Although the Task class exists in the new System.Threading.Tasks namespace: Tasks are not directly related to threads or multithreading. Of course, Task instances will typically be used in our implementation of concurrency within an application, but the Task class itself does not provide the concurrency used.  The Task API supports using Tasks in an entirely single threaded, synchronous manner. Tasks are very much like standard delegates.  You can execute a task synchronously via Task.RunSynchronously(), or you can use Task.Start() to schedule a task to run, typically asynchronously.  This is very similar to using delegate.Invoke to execute a delegate synchronously, or using delegate.BeginInvoke to execute it asynchronously. The Task class adds some nice functionality on top of a standard delegate which improves usability in both synchronous and multithreaded environments. The first addition provided by Task is a means of handling cancellation via the new unified cancellation mechanism of .NET 4.  If the wrapped delegate within a Task raises an OperationCanceledException during it’s operation, which is typically generated via calling ThrowIfCancellationRequested on a CancellationToken, or if the CancellationToken used to construct a Task instance is flagged as canceled, the Task’s IsCanceled property will be set to true automatically.  This provides a clean way to determine whether a Task has been canceled, often without requiring specific exception handling. Tasks also provide a clean API which can be used for waiting on a task.  Although the Task class explicitly implements IAsyncResult, Tasks provide a nicer usage model than the traditional .NET Asynchronous Programming Model.  Instead of needing to track an IAsyncResult handle, you can just directly call Task.Wait() to block until a Task has completed.  Overloads exist for providing a timeout, a CancellationToken, or both to prevent waiting indefinitely.  In addition, the Task class provides static methods for waiting on multiple tasks – Task.WaitAll and Task.WaitAny, again with overloads providing time out options.  This provides a very simple, clean API for waiting on single or multiple tasks. Finally, Tasks provide a much nicer model for Exception handling.  If the delegate wrapped within a Task raises an exception, the exception will automatically get wrapped into an AggregateException and exposed via the Task.Exception property.  This exception is stored with the Task directly, and does not tear down the application.  Later, when Task.Wait() (or Task.WaitAll or Task.WaitAny) is called on this task, an AggregateException will be raised at that point if any of the tasks raised an exception.  For example, suppose we have the following code: Task taskOne = new Task( () => { throw new ApplicationException("Random Exception!"); }); Task taskTwo = new Task( () => { throw new ArgumentException("Different exception here"); }); // Start the tasks taskOne.Start(); taskTwo.Start(); try { Task.WaitAll(new[] { taskOne, taskTwo }); } catch (AggregateException e) { Console.WriteLine(e.InnerExceptions.Count); foreach (var inner in e.InnerExceptions) Console.WriteLine(inner.Message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here, our routine will print: 2 Different exception here Random Exception! Note that we had two separate tasks, each of which raised two distinctly different types of exceptions.  We can handle this cleanly, with very little code, in a much nicer manner than the Asynchronous Programming API.  We no longer need to handle TargetInvocationException or worry about implementing the Event-based Asynchronous Pattern properly by setting the AsyncCompletedEventArgs.Error property.  Instead, we just raise our exception as normal, and handle AggregateException in a single location in our calling code.

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• Set the Minimum and Maximum Tab Widths in Firefox without an Add-on

  - by Lori Kaufman

  If you tend to have a lot of tabs open in Firefox, there may be times when you can’t see all the tabs you have open, and you need to navigate among your tabs using the tab scrolling arrows. There are add-ons available for Firefox that will make multiple rows of tabs, such as Tab Utilities. However, this still may not be ideal, as it takes a lot of screen real estate when you have a lot of tabs open. There’s an easy way to set the width of the tabs, so they still display text or website icons, and, at the same time, allow more tabs to be visible. To change the width of the tabs, enter “about:config” in the address bar in Firefox and press Enter. HTG Explains: Do You Really Need to Defrag Your PC? Use Amazon’s Barcode Scanner to Easily Buy Anything from Your Phone How To Migrate Windows 7 to a Solid State Drive

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• Controlling Brightness in Sony Vaio SVE151A11W |Not Working|

  - by Rabimba Karanjai

  Disclaimer First: I have gone thorugh these following threads here and followed all of their advice but none of them worked Brightness Control Problem on Sony VAIO with NVIDIA GT-320M unable to change brightness settings in sony vaio e series laptop Brightness doesn't change on Sony laptop Now the Problem I have installed Ubuntu 12.10 (64bit) in this Sony Vaio laptop. After vanilla isntallation the brightness keys are workinga nd I can see the brightness indictaor going up and down buit its isn't having any effect on the real brightness of the device. I have installer additional drivers too but that didn't solve the problem. I can't seem to be able to change the brightness. Anyone knows how I can fix this?

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• Week in Geek: Facebook Valentine’s Day Scams Edition

  - by Asian Angel

  This week we learned how to get started with the Linux command-line text editor Nano, “speed up Start Menu searching, halt auto-rotating Android screens, & set up Dropbox-powered torrenting”, change the default application for Android tasks, find great gift recommendations for Valentine’s Day using the How-To Geek Valentine’s Day gift guide, had fun decorating our desktops with TRON and TRON Legacy theme items, and more Latest Features How-To Geek ETC Internet Explorer 9 RC Now Available: Here’s the Most Interesting New Stuff Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware How to Change the Default Application for Android Tasks Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images The How-To Geek Valentine’s Day Gift Guide Inspire Geek Love with These Hilarious Geek Valentines Four Awesome TRON Legacy Themes for Chrome and Iron Anger is Illogical – Old School Style Instructional Video [Star Trek Mashup] Get the Old Microsoft Paint UI Back in Windows 7 Relax and Sleep Is a Soothing Sleep Timer Google Rolls Out Two-Factor Authentication Peaceful Early Morning by the Riverside Wallpaper

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• A Case for Women in Technology

  - by Denise McInerney

  Pragmatic Works and the PASS Women in Tech chapter are co-sponsoring a webinar series featuring women speakers. I presented a session on “A Case for Women in Technology” explaining why we are all affected by the lack of women studying and working in tech. The recording is available here. And here are the slides from that presentation: The presentation includes a link to a trailer for an upcoming documentary. This short video makes a good case for why we need more women creating technology. There are many organizations doing good and important work on this issue. Here are some of them: National Center for Women & Information Technology Catalyst Anita Borg Institute Girls Inc Girls Who Code Code.org Black Girls Code Teaching Kids Programming Digigirlz IGNITE She++ The Ada Initiative PASS WIT Here are the publications I referenced in my slides: Women in IT: The Facts Why Diversity Matters Women in IT: By the Numbers NCWIT Scorecard

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• Guidance: A Branching strategy for Scrum Teams

  - by Martin Hinshelwood

  Having a good branching strategy will save your bacon, or at least your code. Be careful when deviating from your branching strategy because if you do, you may be worse off than when you started! This is one possible branching strategy for Scrum teams and I will not be going in depth with Scrum but you can find out more about Scrum by reading the Scrum Guide and you can even assess your Scrum knowledge by having a go at the Scrum Open Assessment. You can also read SSW’s Rules to Better Scrum using TFS which have been developed during our own Scrum implementations. Acknowledgements Bill Heys – Bill offered some good feedback on this post and helped soften the language. Note: Bill is a VS ALM Ranger and co-wrote the Branching Guidance for TFS 2010 Willy-Peter Schaub – Willy-Peter is an ex Visual Studio ALM MVP turned blue badge and has been involved in most of the guidance including the Branching Guidance for TFS 2010 Chris Birmele – Chris wrote some of the early TFS Branching and Merging Guidance. Dr Paul Neumeyer, Ph.D Parallel Processes, ScrumMaster and SSW Solution Architect – Paul wanted to have feature branches coming from the release branch as well. We agreed that this is really a spin-off that needs own project, backlog, budget and Team. Scenario: A product is developed RTM 1.0 is released and gets great sales.  Extra features are demanded but the new version will have double to price to pay to recover costs, work is approved by the guys with budget and a few sprints later RTM 2.0 is released.  Sales a very low due to the pricing strategy. There are lots of clients on RTM 1.0 calling out for patches. As I keep getting Reverse Integration and Forward Integration mixed up and Bill keeps slapping my wrists I thought I should have a reminder: You still seemed to use reverse and/or forward integration in the wrong context. I would recommend reviewing your document at the end to ensure that it agrees with the common understanding of these terms merge (forward integration) from parent to child (same direction as the branch), and merge  (reverse integration) from child to parent (the reverse direction of the branch). - one of my many slaps on the wrist from Bill Heys.   As I mentioned previously we are using a single feature branching strategy in our current project. The single biggest mistake developers make is developing against the “Main” or “Trunk” line. This ultimately leads to messy code as things are added and never finished. Your only alternative is to NEVER check in unless your code is 100%, but this does not work in practice, even with a single developer. Your ADD will kick in and your half-finished code will be finished enough to pass the build and the tests. You do use builds don’t you? Sadly, this is a very common scenario and I have had people argue that branching merely adds complexity. Then again I have seen the other side of the universe ... branching  structures from he... We should somehow convince everyone that there is a happy between no-branching and too-much-branching. - Willy-Peter Schaub, VS ALM Ranger, Microsoft   A key benefit of branching for development is to isolate changes from the stable Main branch. Branching adds sanity more than it adds complexity. We do try to stress in our guidance that it is important to justify a branch, by doing a cost benefit analysis. The primary cost is the effort to do merges and resolve conflicts. A key benefit is that you have a stable code base in Main and accept changes into Main only after they pass quality gates, etc. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft The second biggest mistake developers make is branching anything other than the WHOLE “Main” line. If you branch parts of your code and not others it gets out of sync and can make integration a nightmare. You should have your Source, Assets, Build scripts deployment scripts and dependencies inside the “Main” folder and branch the whole thing. Some departments within MSFT even go as far as to add the environments used to develop the product in there as well; although I would not recommend that unless you have a massive SQL cluster to house your source code. We tried the “add environment” back in South-Africa and while it was “phenomenal”, especially when having to switch between environments, the disk storage and processing requirements killed us. We opted for virtualization to skin this cat of keeping a ready-to-go environment handy. - Willy-Peter Schaub, VS ALM Ranger, Microsoft   I think people often think that you should have separate branches for separate environments (e.g. Dev, Test, Integration Test, QA, etc.). I prefer to think of deploying to environments (such as from Main to QA) rather than branching for QA). - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   You can read about SSW’s Rules to better Source Control for some additional information on what Source Control to use and how to use it. There are also a number of branching Anti-Patterns that should be avoided at all costs: You know you are on the wrong track if you experience one or more of the following symptoms in your development environment: Merge Paranoia—avoiding merging at all cost, usually because of a fear of the consequences. Merge Mania—spending too much time merging software assets instead of developing them. Big Bang Merge—deferring branch merging to the end of the development effort and attempting to merge all branches simultaneously. Never-Ending Merge—continuous merging activity because there is always more to merge. Wrong-Way Merge—merging a software asset version with an earlier version. Branch Mania—creating many branches for no apparent reason. Cascading Branches—branching but never merging back to the main line. Mysterious Branches—branching for no apparent reason. Temporary Branches—branching for changing reasons, so the branch becomes a permanent temporary workspace. Volatile Branches—branching with unstable software assets shared by other branches or merged into another branch. Note   Branches are volatile most of the time while they exist as independent branches. That is the point of having them. The difference is that you should not share or merge branches while they are in an unstable state. Development Freeze—stopping all development activities while branching, merging, and building new base lines. Berlin Wall—using branches to divide the development team members, instead of dividing the work they are performing. -Branching and Merging Primer by Chris Birmele - Developer Tools Technical Specialist at Microsoft Pty Ltd in Australia   In fact, this can result in a merge exercise no-one wants to be involved in, merging hundreds of thousands of change sets and trying to get a consolidated build. Again, we need to find a happy medium. - Willy-Peter Schaub on Merge Paranoia Merge conflicts are generally the result of making changes to the same file in both the target and source branch. If you create merge conflicts, you will eventually need to resolve them. Often the resolution is manual. Merging more frequently allows you to resolve these conflicts close to when they happen, making the resolution clearer. Waiting weeks or months to resolve them, the Big Bang approach, means you are more likely to resolve conflicts incorrectly. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   Figure: Main line, this is where your stable code lives and where any build has known entities, always passes and has a happy test that passes as well? Many development projects consist of, a single “Main” line of source and artifacts. This is good; at least there is source control . There are however a couple of issues that need to be considered. What happens if: you and your team are working on a new set of features and the customer wants a change to his current version? you are working on two features and the customer decides to abandon one of them? you have two teams working on different feature sets and their changes start interfering with each other? I just use labels instead of branches? That's a lot of “what if’s”, but there is a simple way of preventing this. Branching… In TFS, labels are not immutable. This does not mean they are not useful. But labels do not provide a very good development isolation mechanism. Branching allows separate code sets to evolve separately (e.g. Current with hotfixes, and vNext with new development). I don’t see how labels work here. - Bill Heys, VS ALM Ranger & TFS Branching Lead, Microsoft   Figure: Creating a single feature branch means you can isolate the development work on that branch.   Its standard practice for large projects with lots of developers to use Feature branching and you can check the Branching Guidance for the latest recommendations from the Visual Studio ALM Rangers for other methods. In the diagram above you can see my recommendation for branching when using Scrum development with TFS 2010. It consists of a single Sprint branch to contain all the changes for the current sprint. The main branch has the permissions changes so contributors to the project can only Branch and Merge with “Main”. This will prevent accidental check-ins or checkouts of the “Main” line that would contaminate the code. The developers continue to develop on sprint one until the completion of the sprint. Note: In the real world, starting a new Greenfield project, this process starts at Sprint 2 as at the start of Sprint 1 you would have artifacts in version control and no need for isolation.   Figure: Once the sprint is complete the Sprint 1 code can then be merged back into the Main line. There are always good practices to follow, and one is to always do a Forward Integration from Main into Sprint 1 before you do a Reverse Integration from Sprint 1 back into Main. In this case it may seem superfluous, but this builds good muscle memory into your developer’s work ethic and means that no bad habits are learned that would interfere with additional Scrum Teams being added to the Product. The process of completing your sprint development: The Team completes their work according to their definition of done. Merge from “Main” into “Sprint1” (Forward Integration) Stabilize your code with any changes coming from other Scrum Teams working on the same product. If you have one Scrum Team this should be quick, but there may have been bug fixes in the Release branches. (we will talk about release branches later) Merge from “Sprint1” into “Main” to commit your changes. (Reverse Integration) Check-in Delete the Sprint1 branch Note: The Sprint 1 branch is no longer required as its useful life has been concluded. Check-in Done But you are not yet done with the Sprint. The goal in Scrum is to have a “potentially shippable product” at the end of every Sprint, and we do not have that yet, we only have finished code.   Figure: With Sprint 1 merged you can create a Release branch and run your final packaging and testing In 99% of all projects I have been involved in or watched, a “shippable product” only happens towards the end of the overall lifecycle, especially when sprints are short. The in-between releases are great demonstration releases, but not shippable. Perhaps it comes from my 80’s brain washing that we only ship when we reach the agreed quality and business feature bar. - Willy-Peter Schaub, VS ALM Ranger, Microsoft Although you should have been testing and packaging your code all the way through your Sprint 1 development, preferably using an automated process, you still need to test and package with stable unchanging code. This is where you do what at SSW we call a “Test Please”. This is first an internal test of the product to make sure it meets the needs of the customer and you generally use a resource external to your Team. Then a “Test Please” is conducted with the Product Owner to make sure he is happy with the output. You can read about how to conduct a Test Please on our Rules to Successful Projects: Do you conduct an internal "test please" prior to releasing a version to a client?   Figure: If you find a deviation from the expected result you fix it on the Release branch. If during your final testing or your “Test Please” you find there are issues or bugs then you should fix them on the release branch. If you can’t fix them within the time box of your Sprint, then you will need to create a Bug and put it onto the backlog for prioritization by the Product owner. Make sure you leave plenty of time between your merge from the development branch to find and fix any problems that are uncovered. This process is commonly called Stabilization and should always be conducted once you have completed all of your User Stories and integrated all of your branches. Even once you have stabilized and released, you should not delete the release branch as you would with the Sprint branch. It has a usefulness for servicing that may extend well beyond the limited life you expect of it. Note: Don't get forced by the business into adding features into a Release branch instead that indicates the unspoken requirement is that they are asking for a product spin-off. In this case you can create a new Team Project and branch from the required Release branch to create a new Main branch for that product. And you create a whole new backlog to work from.   Figure: When the Team decides it is happy with the product you can create a RTM branch. Once you have fixed all the bugs you can, and added any you can’t to the Product Backlog, and you Team is happy with the result you can create a Release. This would consist of doing the final Build and Packaging it up ready for your Sprint Review meeting. You would then create a read-only branch that represents the code you “shipped”. This is really an Audit trail branch that is optional, but is good practice. You could use a Label, but Labels are not Auditable and if a dispute was raised by the customer you can produce a verifiable version of the source code for an independent party to check. Rare I know, but you do not want to be at the wrong end of a legal battle. Like the Release branch the RTM branch should never be deleted, or only deleted according to your companies legal policy, which in the UK is usually 7 years.   Figure: If you have made any changes in the Release you will need to merge back up to Main in order to finalise the changes. Nothing is really ever done until it is in Main. The same rules apply when merging any fixes in the Release branch back into Main and you should do a reverse merge before a forward merge, again for the muscle memory more than necessity at this stage. Your Sprint is now nearly complete, and you can have a Sprint Review meeting knowing that you have made every effort and taken every precaution to protect your customer’s investment. Note: In order to really achieve protection for both you and your client you would add Automated Builds, Automated Tests, Automated Acceptance tests, Acceptance test tracking, Unit Tests, Load tests, Web test and all the other good engineering practices that help produce reliable software.     Figure: After the Sprint Planning meeting the process begins again. Where the Sprint Review and Retrospective meetings mark the end of the Sprint, the Sprint Planning meeting marks the beginning. After you have completed your Sprint Planning and you know what you are trying to achieve in Sprint 2 you can create your new Branch to develop in. How do we handle a bug(s) in production that can’t wait? Although in Scrum the only work done should be on the backlog there should be a little buffer added to the Sprint Planning for contingencies. One of these contingencies is a bug in the current release that can’t wait for the Sprint to finish. But how do you handle that? Willy-Peter Schaub asked an excellent question on the release activities: In reality Sprint 2 starts when sprint 1 ends + weekend. Should we not cater for a possible parallelism between Sprint 2 and the release activities of sprint 1? It would introduce FI’s from main to sprint 2, I guess. Your “Figure: Merging print 2 back into Main.” covers, what I tend to believe to be reality in most cases. - Willy-Peter Schaub, VS ALM Ranger, Microsoft I agree, and if you have a single Scrum team then your resources are limited. The Scrum Team is responsible for packaging and release, so at least one run at stabilization, package and release should be included in the Sprint time box. If more are needed on the current production release during the Sprint 2 time box then resource needs to be pulled from Sprint 2. The Product Owner and the Team have four choices (in order of disruption/cost): Backlog: Add the bug to the backlog and fix it in the next Sprint Buffer Time: Use any buffer time included in the current Sprint to fix the bug quickly Make time: Remove a Story from the current Sprint that is of equal value to the time lost fixing the bug(s) and releasing. Note: The Team must agree that it can still meet the Sprint Goal. Cancel Sprint: Cancel the sprint and concentrate all resource on fixing the bug(s) Note: This can be a very costly if the current sprint has already had a lot of work completed as it will be lost. The choice will depend on the complexity and severity of the bug(s) and both the Product Owner and the Team need to agree. In this case we will go with option #2 or #3 as they are uncomplicated but severe bugs. Figure: Real world issue where a bug needs fixed in the current release. If the bug(s) is urgent enough then then your only option is to fix it in place. You can edit the release branch to find and fix the bug, hopefully creating a test so it can’t happen again. Follow the prior process and conduct an internal and customer “Test Please” before releasing. You can read about how to conduct a Test Please on our Rules to Successful Projects: Do you conduct an internal "test please" prior to releasing a version to a client?   Figure: After you have fixed the bug you need to ship again. You then need to again create an RTM branch to hold the version of the code you released in escrow.   Figure: Main is now out of sync with your Release. We now need to get these new changes back up into the Main branch. Do a reverse and then forward merge again to get the new code into Main. But what about the branch, are developers not working on Sprint 2? Does Sprint 2 now have changes that are not in Main and Main now have changes that are not in Sprint 2? Well, yes… and this is part of the hit you take doing branching. But would this scenario even have been possible without branching?   Figure: Getting the changes in Main into Sprint 2 is very important. The Team now needs to do a Forward Integration merge into their Sprint and resolve any conflicts that occur. Maybe the bug has already been fixed in Sprint 2, maybe the bug no longer exists! This needs to be identified and resolved by the developers before they continue to get further out of Sync with Main. Note: Avoid the “Big bang merge” at all costs.   Figure: Merging Sprint 2 back into Main, the Forward Integration, and R0 terminates. Sprint 2 now merges (Reverse Integration) back into Main following the procedures we have already established.   Figure: The logical conclusion. This then allows the creation of the next release. By now you should be getting the big picture and hopefully you learned something useful from this post. I know I have enjoyed writing it as I find these exploratory posts coupled with real world experience really help harden my understanding.  Branching is a tool; it is not a silver bullet. Don’t over use it, and avoid “Anti-Patterns” where possible. Although the diagram above looks complicated I hope showing you how it is formed simplifies it as much as possible.   Technorati Tags: Branching,Scrum,VS ALM,TFS 2010,VS2010

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• Are high powered 3D game engines better at 2D games than engines made for 2D

  - by Adam

  I'm a software engineer that's new to game programming so forgive me if this is a dumb question as I don't know that much about game engines. If I was building a 2D game am I better off going with an engine like Torque that looks like it's built for 2D, or would higher powered engines like Unreal, Source and Unity work better? I'm mainly asking if 2D vs 3D is a large factor in choosing an engine. For the purpose of comparison, let's eliminate variables by saying price isn't a factor (even though it probably is). EDIT: I should probably also mention that the game we're developing has a lot of RTS and RPG elements regarding leveling up

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• What a Performance! MySQL 5.5 and InnoDB 1.1 running on Oracle Linux

  - by zeynep.koch(at)oracle.com

  The MySQL performance team in Oracle has recently completed a series of benchmarks comparing Read / Write and Read-Only performance of MySQL 5.5 with the InnoDB and MyISAM storage engines. Compared to MyISAM, InnoDB delivered 35x higher throughput on the Read / Write test and 5x higher throughput on the Read-Only test, with 90% scalability across 36 CPU cores. A full analysis of results and MySQL configuration parameters are documented in a new whitepaperIn addition to the benchmark, the new whitepaper, also includes:- A discussion of the use-cases for each storage engine- Best practices for users considering the migration of existing applications from MyISAM to InnoDB- A summary of the performance and scalability enhancements introduced with MySQL 5.5 and InnoDB 1.1.The benchmark itself was based on Sysbench, running on AMD Opteron "Magny-Cours" processors, and Oracle Linux with the Unbreakable Enterprise Kernel You can learn more about MySQL 5.5 and InnoDB 1.1 from here and download it from here to test whether you witness performance gains in your real-world applications.  By Mat Keep

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• How to Play FLAC Files in Windows 7 Media Center & Player

  - by Mysticgeek

  An annoyance for music lovers who enjoy FLAC format, is there’s no native support for WMP or WMC. If you’re a music enthusiast who prefers FLAC format, we’ll look at adding support to Windows 7 Media Center and Player. For the following article we are using Windows 7 Home Premium 32-bit edition. Download and Install madFLAC v1.8 The first thing we need to do is download and install the madFLAC v1.8 decoder (link below). Just unzip the file and run install.bat… You’ll get a message that it has been successfully registered, click Ok. To verify everything is working, open up one of your FLAC files with WMP, and you’ll get the following message. Check the box Don’t ask me again for this extension and click Yes. Now Media Player should play the track you’ve chosen.   Delete Current Music Library But what if you want to add your entire collection of FLAC files to the Library? If you already have it set up as your default music player, unfortunately we need to remove the current library and delete the database. The best way to manage the music library in Windows 7 is via WMP 12. Since we don’t want to delete songs from the computer we need to Open WMP, press “Alt+T” and navigate to Tools \ Options \ Library.   Now uncheck the box Delete files from computer when deleted from library and click Ok. Now in your Library click “Ctrl + A” to highlight all of the songs in the Library, then hit the “Delete” key. If you have a lot of songs in your library (like on our system) you’ll see the following dialog box while it collects all of the information.   After all of the data is collected, make sure the radio button next to Delete from library only is marked and click Ok. Again you’ll see the Working progress window while the songs are deleted. Deleting Current Database Now we need to make sure we’re starting out fresh. Close out of Media Player, then we’ll basically follow the same directions The Geek pointed out for fixing the WMP Library. Click on Start and type in services.msc into the search box and hit Enter. Now scroll down and stop the service named Windows Media Player Network Sharing Service. Now, navigate to the following directory and the main file to delete CurrentDatabase_372.wmdb %USERPROFILE%\Local Settings\Application Data\Microsoft\Media Player\ Again, the main file to delete is CurrentDatabase_372.wmdb, though if you want, you can delete them all. If you’re uneasy about deleting these files, make sure to back them up first. Now after you restart WMP you can begin adding your FLAC files. For those of us with large collections, it’s extremely annoying to see WMP try to pick up all of your media by default. To delete the other directories go to Organize \ Manage Libraries then open the directories you want to remove. For example here we’re removing the default libraries it tries to check for music. Remove the directories you don’t want it to gather contents from in each of the categories. We removed all of the other collections and only added the FLAC music directory from our home server. SoftPointer Tag Support Plugin Even though we were able to get FLAC files to play in WMP and WMC at this point, there’s another utility from SoftPointer to add. It enables FLAC (and other file formats) to be picked up in the library much easier. It has a long name but is effective –M4a/FLAC/Ogg/Ape/Mpc Tag Support Plugin for Media Player and Media Center (link below). Just install it by accepting the defaults, and you’ll be glad you did. After installing it, and re-launching Media Player, give it some time to collect all of the data from your FLAC directory…it can take a while. In fact, if your collection is huge, just walk away and let it do its thing. If you try to use it right away, WMP slows down considerably while updating the library.   Once the library is setup you’ll be able to play your FLAC tunes in Windows 7 Media Center as well and Windows Media Player 12.   Album Art One caveat is that some of our albums didn’t show any cover art. But we were usually able to get it by right-clicking the album and selecting Find album info.   Then confirming the album information is correct…   Conclusion Although this seems like several steps to go through to play FLAC files in Windows 7 Media Center and Player, it seems to work really well after it’s set up. We haven’t tried this with a 64-bit machine, but the process should be similar, but you might want to make sure the codecs you use are 64-bit. We’re sure there are other methods out there that some of you use, and if so leave us a comment and tell us about it. Download madFlac V1.8  M4a/FLAC/Ogg/Ape/Mpc Tag Support Plugin for Media Player and Media Center from SoftPointer Similar Articles Productive Geek Tips How to Play .OGM Video Files in Windows VistaFixing When Windows Media Player Library Won’t Let You Add FilesUsing Netflix Watchnow in Windows Vista Media Center (Gmedia)Kantaris is a Unique Media Player Based on VLCEasily Change Audio File Formats with XRECODE TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional OutSync will Sync Photos of your Friends on Facebook and Outlook Windows 7 Easter Theme YoWindoW, a real time weather screensaver Optimize your computer the Microsoft way Stormpulse provides slick, real time weather data Geek Parents – Did you try Parental Controls in Windows 7?

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• WPF ListView as a DataGrid – Part 3

  - by psheriff

  I have had a lot of great feedback on the blog post about turning the ListView into a DataGrid by creating GridViewColumn objects on the fly. So, in the last 2 parts, I showed a couple of different methods for accomplishing this. Let’s now look at one more and that is use Reflection to extract the properties from a Product, Customer, or Employee object to create the columns. Yes, Reflection is a slower approach, but you could create the columns one time then cache the View object for re-use. Another potential drawback is you may have columns in your object that you do not wish to display on your ListView. But, just because so many people asked, here is how to accomplish this using Reflection.   Figure 1: Use Reflection to create GridViewColumns. Using Reflection to gather property names is actually quite simple. First you need to pass any type (Product, Customer, Employee, etc.) to a method like I did in my last two blog posts on this subject. Below is the method that I created in the WPFListViewCommon class that now uses reflection. C#public static GridView CreateGridViewColumns(Type anyType){  // Create the GridView  GridView gv = new GridView();  GridViewColumn gvc;   // Get the public properties.  PropertyInfo[] propInfo =          anyType.GetProperties(BindingFlags.Public |                                BindingFlags.Instance);   foreach (PropertyInfo item in propInfo)  {    gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.Name);    gvc.Header = item.Name;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   return gv;} VB.NETPublic Shared Function CreateGridViewColumns( _  ByVal anyType As Type) As GridView  ' Create the GridView   Dim gv As New GridView()  Dim gvc As GridViewColumn   ' Get the public properties.   Dim propInfo As PropertyInfo() = _    anyType.GetProperties(BindingFlags.Public Or _                          BindingFlags.Instance)   For Each item As PropertyInfo In propInfo    gvc = New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.Name)    gvc.Header = item.Name    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   Return gvEnd Function The key to using Relection is using the GetProperties method on the type you pass in. When you pass in a Product object as Type, you can now use the GetProperties method and specify, via flags, which properties you wish to return. In the code that I wrote, I am just retrieving the Public properties and only those that are Instance properties. I do not want any static/Shared properties or private properties. GetProperties returns an array of PropertyInfo objects. You can loop through this array and build your GridViewColumn objects by reading the Name property from the PropertyInfo object. Build the Product Screen To populate the ListView shown in Figure 1, you might write code like the following: C#private void CollectionSample(){  Product prod = new Product();   // Setup the GridView Columns  lstData.View =      WPFListViewCommon.CreateGridViewColumns(typeOf(Product));  lstData.DataContext = prod.GetProducts();} VB.NETPrivate Sub CollectionSample()  Dim prod As New Product()   ' Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns( _       GetType(Product))  lstData.DataContext = prod.GetProducts()End Sub All you need to do now is to pass in a Type object from your Product class that you can get by using the typeOf() function in C# or the GetType() function in VB. That’s all there is to it! Summary There are so many different ways to approach the same problem in programming. That is what makes programming so much fun! In this blog post I showed you how to create ListView columns on the fly using Reflection. This gives you a lot of flexibility without having to write extra code as was done previously. NOTE: You can download the complete sample code (in both VB and C#) at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "WPF ListView as a DataGrid – Part 3" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free eBook on "Fundamentals of N-Tier".  

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• Podcast: Advanced MVVM with Josh Smith

  - by craigshoemaker

  Author, Microsoft MVP and accomplished pianist Josh Smith, Sr. UX Developer at IdentityMine, joins the show to discuss some of Model View ViewModel’s more advanced scenarios. Full Speed: download Fast Version: download Josh shares is experience using MVVM gives some real-world advice on: Using modal dialogs Evils and virtues of code behind in views Use of attached behaviors Undo/redo strategies Working with animations Building a task based architecture for managing communication between View and ViewModel Frameworks in the MVVM space The Book Get first-hand experience implementing the solutions to the challenges discussed in the show by reading Josh’s new book ‘Advanced MVVM’. Resources The following resources are mentioned in the show: Laurent Bugnion's mix talk ‘Understanding the Model-View-ViewModel Pattern Josh Smith’s MVVM Foundation Laurent Bugnion’s MVVM Light framework Rob Eisenberg's Caliburn

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• Starting Web Development, Confused between Ruby and PHP [closed]

  - by KyelJmD

  I am on summer vacation, but I want to learn web development, The current programming language I know are the following C# Java C and I know the following scripting and markup language Javascript HTML and a little bit of PHP. but I wanted to know where would I learn most? should I venture on PHP? or Ruby on Rails? I don't have any experience or knowledge with regards to Ruby and of course ruby on rails, but I am gussing Ruby is a pre-requisite for learning the Ruby on rails framework right? Now the question, WHat are the pros and cons of both these language, is ruby worth learning just for Ruby on rails? and which has a higher market?

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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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• Objective C and C++ for Game Development

  - by Holland

  I'm trying to figure out which language I should begin learning. I've only been programming for about 6 months, with languages like PHP, Java, and C#. I want to learn how to dev games, and while I know in most cases the answer to this would be through C++ (at least, I would think), though I'm still curious about what Objective C can offer in the sense of long term benefit. It seems like there's a chance that Objective-C may actually become more popular than C++ in a few years, and for all I know, it may become the de facto standard development language for games. Still, despite all of this, I really don't know anything, and this is all speculation. Both languages seem very interesting, and obviously can pull a lot of out of themselves. What do you think? Note: despite what some might say, I really don't want to end up using prebuilt engines, and would rather just learn how to make my own. I'm well aware that it takes a lot more time, but I'm quite ok with that.

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