Search Results

Search found 18249 results on 730 pages for 'real world haskell'.

Page 611/730 | < Previous Page | 607 608 609 610 611 612 613 614 615 616 617 618  | Next Page >

• Typical Hadoop setup for remote job submission

  - by Artii

  So I am still a bit new to hadoop and am currently in the process of setting up a small test cluster on Amazonaws. So my question relates to some tips on the structuring of the cluster so it is possible to work submit jobs from remote machines. Currently I have 5 machines. 4 are basically the Hadoop cluster with the NameNodes, Yarn etc. One machine is used as a manager machine( Cloudera Manager). I am gonna describe my thinking process on the setup and if anyone can chime in the points I am not clear with, that would be great. I was thinking what was the best setup for a small cluster. So I decided to expose only one manager machine and probably use that to submit all the jobs through it. The other machines will see each other etc, but not be accessible from the outside world. I am have conceptual idea on how to do this,but I am not sure how to properly go about doing this though, if anyone could point me in the right direction that would great. Also another big point is, I want to be able to submit jobs to the cluster through exposed machine from a client machine (might be Windows). I am not so clear on this setup as well. Do I need to have Hadoop installed on the machine in order to use the normal hadoop commands, and to write/submit jobs say from Eclipse or something similar. So to sum it up my questions are, Is this an ok setup for a small test cluster How can I go about using one exposed machine to submit/route jobs to the cluster, without having any of the Hadoop nodes on it. How do I setup a client machine to submit jobs to a remote cluster, and an example on how to do it on Windows. Also if there are any reason not to use Windows as a client machine in this setup. Thanks I would greatly appreciate any advice or help on this.

  Read the article

• Big trouble after app update. CoreData migration error

  - by MrBr

  this morning we had a big trouble with our iphone app. We had to even take it off the store. The thing is that we made real small changes to our xcdatamodel. We thought that the update process is automatically taking care about exchanging it the right way until we found out something like CoreData migration exists. We are using the UIManagedDocument to connect to the persistent store. How is it possible to exchange this file with the new one? While we were developing we just uninstalled the whole app from the device and then installed it again and everything worked. How can we simulate this process in the app store with updates? UPDATE I try to set the migration option like this _database = [[UIIManagedDocument alloc] init]; NSMutableDictionary *options = [[NSMutableDictionary alloc] init]; [options setObject:[NSNumber numberWithBool:YES] forKey:NSMigratePersistentStoresAutomaticallyOption], _database.persistentStoreOptions = options; but the app is still crashing with ** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'This NSPersistentStoreCoordinator has no persistent stores. It cannot perform a save operation.'

  Read the article

• How to maintain long-lived python projects w.r.t. dependencies and python versions ?

  - by Gyom

  short version: how can I get rid of the multiple-versions-of-python nightmare ? long version: over the years, I've used several versions of python, and what is worse, several extensions to python (e.g. pygame, pylab, wxPython...). Each time it was on a different setup, with different OSes, sometimes different architectures (like my old PowerPC mac). Nowadays I'm using a mac (OSX 10.6 on x86-64) and it's a dependency nightmare each time I want to revive script older than a few months. Python itself already comes in three different flavours in /usr/bin (2.5, 2.6, 3.1), but I had to install 2.4 from macports for pygame, something else (cannot remember what) forced me to install all three others from macports as well, so at the end of the day I'm the happy owner of seven (!) instances of python on my system. But that's not the problem, the problem is, none of them has the right (i.e. same set of) libraries installed, some of them are 32bits, some 64bits, and now I'm pretty much lost. For example right now I'm trying to run a three-year-old script (not written by me) which used to use matplotlib/numpy to draw a real-time plot within a rectangle of a wxwidgets window. But I'm failing miserably: py26-wxpython from macports won't install, stock python has wxwidgets included but also has some conflict between 32 bits and 64 bits, and it doesn't have numpy... what a mess ! Obviously, I'm doing things the wrong way. How do you usally cope with all that chaos ?

  Read the article

• PHP MySQLi isn't letting me alter a table (adding a new column)

  - by asdasd

  Well thats pretty much it. This is my query: $query = 'ALTER TABLE permissions ADD '.$name.' INT NOT NULL DEFAULT \'0\''; Where $name is already checked to exist with only lower case alpha letters, and not more than 20 length. Im just starting this out with very simple names. The next 4 lines of code after that one are: if($stmt = $db -> prepare($query)) { $success = $stmt -> execute(); $stmt -> close(); if(!$success) echo 'ERROR: Unsuccessful query: ',$db->error,PHP_EOL; } And I get back, every time ERROR: Unsuccessful query: And no error message. Is there a way to get more error messages so I can see what is failing? I can add new columns through phpmyadmin, but that really doesnt help me at all. The $db is fine, i do lots of stuff before and after this one section. It is only adding new column to the table that fails. side question: prepare() rejected my query every time when i tried to make those 2 variables, the $name and the 0 value as ? ? prepared statement values. Thats why they are in the real query and not bound later. If i could change that too I would like that.

  Read the article

• designing an ASP.NET MVC partial view - showing user choices within a large set of choices

  - by p.campbell

  Consider a partial view whose job is to render markup for a pizza order. The desire is to reuse this partial view in the Create, Details, and Update views. It will always be passed an IEnumerable<Topping>, and output a multitude of checkboxes. There are lots... maybe 40 in all (yes, that might smell). A-OK so far. Problem The question is around how to include the user's choices on the Details and Update views. From the datastore, we've got a List<ChosenTopping>. The goal is to have each checkbox set to true for each chosen topping. What's the easiest to read, or most maintainable way to achieve this? Potential Solutions Create a ViewModel with the List and List. Write out the checkboxes as per normal. While writing each, check whether the ToppingID exists in the list of ChosenTopping. Create a new ViewModel that's a hybrid of both. Perhaps call it DisplayTopping or similar. It would have property ID, Name and IsUserChosen. The respective controller methods for Create, Update, and Details would have to create this new collection with respect to the user's choices as they see fit. The Create controller method would basically set all to false so that it appears to be a blank slate. The real application isn't pizza, and the organization is a bit different from the fakeshot, but the concept is the same. Is it wise to reuse the control for the 3 different scenarios? How better can you display the list of options + the user's current choices? Would you use jQuery instead to show the user selections? Any other thoughts on the potential smell of splashing up a whole bunch of checkboxes?

  Read the article

• Generics vs inheritance (when no collection classes are involved)

  - by Ram

  This is an extension of this questionand probably might even be a duplicate of some other question(If so, please forgive me). I see from MSDN that generics are usually used with collections The most common use for generic classes is with collections like linked lists, hash tables, stacks, queues, trees and so on where operations such as adding and removing items from the collection are performed in much the same way regardless of the type of data being stored. The examples I have seen also validate the above statement. Can someone give a valid use of generics in a real-life scenario which does not involve any collections ? Pedantically, I was thinking about making an example which does not involve collections public class Animal<T> { public void Speak() { Console.WriteLine("I am an Animal and my type is " + typeof(T).ToString()); } public void Eat() { //Eat food } } public class Dog { public void WhoAmI() { Console.WriteLine(this.GetType().ToString()); } } and "An Animal of type Dog" will be Animal<Dog> magic = new Animal<Dog>(); It is entirely possible to have Dog getting inherited from Animal (Assuming a non-generic version of Animal)Dog:Animal Therefore Dog is an Animal Another example I was thinking was a BankAccount. It can be BankAccount<Checking>,BankAccount<Savings>. This can very well be Checking:BankAccount and Savings:BankAccount. Are there any best practices to determine if we should go with generics or with inheritance ?

  Read the article

• rabbitmq-erlang-client, using rebar friendly pkg, works on dev env fails on rebar release

  - by lfurrea

  I am successfully using the rebar-friendly package of rabbitmq-erlang-client for a simple Hello World rebarized and OTP "compliant" app and things work fine on the dev environment. I am able to fire up an erl console and do my application:start(helloworld). and connect to the broker, open up a channel and communicate to queues. However, then I proceed to do rebar generate and it builds up the release just fine, but when I try to fire up from the self contained release package then things suddenly explode. I know rebar releases are known to be an obscure art, but I would like to know what are my options as far as deployment for an app using the rabbitmq-erlang-client. Below you will find the output of the console on the crash: =INFO REPORT==== 18-Dec-2012::16:41:35 === application: session_record exited: {{{badmatch, {error, {'EXIT', {undef, [{amqp_connection_sup,start_link, [{amqp_params_network,<<"guest">>,<<"guest">>,<<"/">>, "127.0.0.1",5672,0,0,0,infinity,none, [#Fun<amqp_auth_mechanisms.plain.3>, #Fun<amqp_auth_mechanisms.amqplain.3>], [],[]}], []}, {supervisor2,do_start_child_i,3, [{file,"src/supervisor2.erl"},{line,391}]}, {supervisor2,handle_call,3, [{file,"src/supervisor2.erl"},{line,413}]}, {gen_server,handle_msg,5, [{file,"gen_server.erl"},{line,588}]}, {proc_lib,init_p_do_apply,3, [{file,"proc_lib.erl"},{line,227}]}]}}}}, [{amqp_connection,start,1, [{file,"src/amqp_connection.erl"},{line,164}]}, {hello_qp,start_link,0,[{file,"src/hello_qp.erl"},{line,10}]}, {session_record_sup,init,1, [{file,"src/session_record_sup.erl"},{line,55}]}, {supervisor_bridge,init,1, [{file,"supervisor_bridge.erl"},{line,79}]}, {gen_server,init_it,6,[{file,"gen_server.erl"},{line,304}]}, {proc_lib,init_p_do_apply,3, [{file,"proc_lib.erl"},{line,227}]}]}, {session_record_app,start,[normal,[]]}} type: permanent

  Read the article

• Architecture for database analytics

  - by David Cournapeau

  Hi, We have an architecture where we provide each customer Business Intelligence-like services for their website (internet merchant). Now, I need to analyze those data internally (for algorithmic improvement, performance tracking, etc...) and those are potentially quite heavy: we have up to millions of rows / customer / day, and I may want to know how many queries we had in the last month, weekly compared, etc... that is the order of billions entries if not more. The way it is currently done is quite standard: daily scripts which scan the databases, and generate big CSV files. I don't like this solutions for several reasons: as typical with those kinds of scripts, they fall into the write-once and never-touched-again category tracking things in "real-time" is necessary (we have separate toolset to query the last few hours ATM). this is slow and non-"agile" Although I have some experience in dealing with huge datasets for scientific usage, I am a complete beginner as far as traditional RDBM go. It seems that using column-oriented database for analytics could be a solution (the analytics don't need most of the data we have in the app database), but I would like to know what other options are available for this kind of issues.

  Read the article

• How to put JFrame into existing JPanel in Java Swing?

  - by suud

  I have an open-source java swing application like this: http://i47.tinypic.com/dff4f7.jpg You can see in the screenshot, there is a JPanel divided into two area, left and right area. The left area has many text links. When I click the SLA Criteria link, it will pop-up the SLA Criteria window. The pop-up window is JFrame object. Now, I'm trying to put the pop-up window into right area of the JPanel, so that means no pop-up window anymore, i.e. when I click the SLA Criteria link, its contents will be displayed at the right area of the JPanel. The existing content of the right area of JPanel will not be used anymore. The example illustration (note: it's made and edited using image editor, this is not the real screenshot of working application) is like this: http://i48.tinypic.com/5vrxaa.jpg So, I would like to know is there a way to put JFrame into JPanel? I'm thinking of using JInternalFrame, is it possible? Or is there another way? UPDATE: Source code: http://pastebin.com/tiqRbWP8 (VTreePanel.java, this is the JPanel) http://pastebin.com/330z3yuT (CPanel.java, this is the super class of VTreePanel) http://pastebin.com/MkNsbtjh (AWindow.java, this is the JFrame, pop-up window) http://pastebin.com/2rsppQeE (CFrame.java, this is the super class of AWindow)

  Read the article

• MemoryFailPoint fires to early in WinXP 64

  - by msedi

  Hello, I have created a volume class (called VoxelVolume) with a self-organizing memory management, since the GC in C# didn't provide a good mechanism for managing contents of the volume for mapping, unmapping and remapping. Although I could have used the mechanisms of virtual memory, the problem is that the files are often too large to fit into the page file and I don't want to force the users to increase the pagefile size. Currently this system is working quite well and there is no problem in lacking resources and OutOfMemoryExceptions since the InsufficientMemoryException using the MemoryFailPoint works quite well. This was all testes on a 32bit WinXP system with 2GB of main memory. Running the same mechanism on 64bit system with 32GB of main memory also works well, but when the application runs the MemoryFailPoint suddenly throws an exception although 24GB of main memory are still free. Another point is when the MemoryFailPoint has fired once, it fires everytime and there is no chance to get rid of it. What I have read so far, that there is a small object and a large object heap (SOH and LOH). But only for the SOH the GC takes real care of and I can free the SOH from unused objects by applying GC.Collect() and GC.WaitForPendingFinalizers. The MemoryFailPoint is obviously the only way to get a little bit of control for the LOH, but since there is enough memory left on the system I see no reason why the MemoryFilePoint should fire. Is there any experience around here using the MemoryFailPoint? Thank you for your help Martin

  Read the article

• Drawing an image in Java, slow as hell on a netbook.

  - by Norswap

  In follow-up to my previous questions (especially this one : http://stackoverflow.com/questions/2684123/java-volatileimage-slower-than-bufferedimage), i have noticed that simply drawing an Image (it doesn't matter if it's buffered or volatile, since the computer has no accelerated memory*, and tests shows it's doesn't change anything), tends to be very long. (*) System.out.println(GraphicsEnvironment.getLocalGraphicsEnvironment() .getDefaultScreenDevice().getAvailableAcceleratedMemory()); --> 0 How long ? For a 500x400 image, about 0.04 seconds. This is only drawing the image on the backbuffer (obtained via buffer strategy). Now considering that world of warcraft runs on that netbook (tough it is quite laggy) and that online java games seems to have no problem whatsoever, this is quite thought provoking. I'm quite certain I didn't miss something obvious, I've searched extensively the web, but nothing will do. So do any of you java whiz have an idea of what obscure problem might be causing this (or maybe it is normal, tough I doubt it) ? PS : As I'm writing this I realized this might be cause by my Linux installation (archlinux) tough I have the correct Intel driver. But my computer normally has "Integrated Intel Graphics Media Accelerator 950", which would mean it should have accelerated video memory somehow. Any ideas about this side of things ?

  Read the article

• How to solve generic algebra using solver/library programmatically? Matlab, Mathematica, Wolfram etc?

  - by DevDevDev

  I'm trying to build an algebra trainer for students. I want to construct a representative problem, define constraints and relationships on the parameters, and then generate a bunch of Latex formatted problems from the representation. As an example: A specific question might be: If y < 0 and (x+3)(y-5) = 0, what is x? Answer (x = -3) I would like to encode this as a Latex formatted problem like. If $y<0$ and $(x+constant_1)(y+constant_2)=0$ what is the value of x? Answer = -constant_1 And plug into my problem solver constant_1 > 0, constant_1 < 60, constant_1 = INTEGER constant_2 < 0, constant_2 > -60, constant_2 = INTEGER Then it will randomly construct me pairs of (constant_1, constant_2) that I can feed into my Latex generator. Obviously this is an extremely simple example with no real "solving" but hopefully it gets the point across. Things I'm looking for ideally in priority order * Solve algebra problems * Definition of relationships relatively straight forward * Rich support for latex formatting (not just writing encoded strings) Thanks!

  Read the article

• subquery in join with doctrine dql

  - by Martijn de Munnik

  I want to use DQL to create a query which looks like this in SQL: select e.* from e inner join ( select uuid, max(locale) as locale from e where locale = 'nl_NL' or locale = 'nl' group by uuid ) as e_ on e.uuid = e_.uuid and e.locale = e_.locale I tried to use QueryBuilder to generate the query and subquery. I think they do the right thing by them selves but I can't combine them in the join statement. Does anybody now if this is possible with DQL? I can't use native SQL because I want to return real objects and I don't know for which object this query is run (I only know the base class which have the uuid and locale property). $subQueryBuilder = $this->_em->createQueryBuilder(); $subQueryBuilder ->addSelect('e.uuid, max(e.locale) as locale') ->from($this->_entityName, 'e') ->where($subQueryBuilder->expr()->in('e.locale', $localeCriteria)) ->groupBy('e.uuid'); $queryBuilder = $this->_em->createQueryBuilder(); $queryBuilder ->addSelect('e') ->from($this->_entityName, 'e') ->join('('.$subQueryBuilder.') as', 'e_')->join ->where('e.uuid = e_.uuid') ->andWhere('e.locale = e_.locale');

  Read the article

• Getting the avg of the top 10 students from each school

  - by dave

  Hi all -- We have a school district with 38 elementary schools. The kids took a test. The averages for the schools are widely dispersed, but I want to compare the averages of JUST THE TOP 10 students from each school. Requirement: use temporary tables only. I have done this in a very work-intensive, error-prone sort of way as follows. (sch_code = e.g., 9043; -- schabbrev = e.g., "Carter"; -- totpct_stu = e.g., 61.3) DROP TEMPORARY TABLE IF EXISTS avg_top10 ; CREATE TEMPORARY TABLE avg_top10 ( sch_code VARCHAR(4), schabbrev VARCHAR(75), totpct_stu DECIMAL(5,1) ); INSERT INTO avg_top10 SELECT sch_code , schabbrev , totpct_stu FROM test_table WHERE sch_code IN ('5489') ORDER BY totpct_stu DESC LIMIT 10; -- I do that last query for EVERY school, so the total -- length of the code is well in excess of 300 lines. -- Then, finally... SELECT schabbrev, ROUND( AVG( totpct_stu ), 1 ) AS top10 FROM avg_top10 GROUP BY schabbrev ORDER BY top10 ; -- OUTPUT: ----------------------------------- schabbrev avg_top10 ---------- --------- Goulding 75.4 Garth 77.7 Sperhead 81.4 Oak_P 83.7 Spring 84.9 -- etc... Question: So this works, but isn't there a lot better way to do it? Thanks! PS -- Looks like homework, but this is, well...real.

  Read the article

• Where does "new" fit in the flex creation cycle?

  - by deux11

  In the following code, the call to myChild.bar() results in an exception because myChild is null. myParent is a valid object. What I don't understand is why myChild has not been created yet. I have read the following document related to object creation sequence, but I am unsure how "new" is related: http://livedocs.adobe.com/flex/3/html/help.html?content=layoutperformance_03.html Any help is appreciated! // Main.mxml <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" creationComplete="created()"> <mx:Script> <![CDATA[ public var myParent:Parent = new Parent(); public function created():void { myParent.foo(); } ]]> </mx:Script> </mx:Application> // Parent.mxml <mx:Canvas xmlns:mx="http://www.adobe.com/2006/mxml" xmlns="*"> <mx:Script> <![CDATA[ public function foo():void { myChild.bar(); } ]]> </mx:Script> <Child id="myChild"/> </mx:Canvas> // Child.mxml <mx:Canvas xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Script> <![CDATA[ public function bar():void { trace("Hello World"); } ]]> </mx:Script> </mx:Canvas>

  Read the article

• DOM manipulation in PHP

  - by bluedaniel

  Hello everyone, Im trying to use the DOM in PHP to do a pretty specific job and Ive got no luck so far, the objective is to take a string of HTML from a Wordpress blog post (from the DB, this is a wordpress plugin). And then out of that HTML replace <div id="do_not_edit">old content</div>" with <div id="do_not_edit">new content</div>" in its place. Saving anything above and below that div in its structure. Then save the HTML back into the DB, should be simple really, I have read that a regex wouldnt be the right way to go here so Ive turned to the DOM instead. The problem is I just cant get it to work, cant extract the div or anything. Help me!! UPDATE The HTML coming out of the wordpress table looks like: Congratulations on finding us here on the world wide web, we are on a mission to create a website that will show off your culinary skills better than any other website does. <div id="do_not_edit">blah blah</div> We want this website to be fun and easy to use, we strive for simple elegance and incredible functionality.We aim to provide a 'complete package'. By this we want to create a website where people can meet, share ideas and help each other out. After several different (incorrect) workings all Ive got below is: $content = ($wpdb->get_var( "SELECT `post_content` FROM $wpdb->posts WHERE ID = {$article[post_id]}" )); $doc = new DOMDocument(); $doc->validateOnParse = true; $doc->loadHTMLFile($content); $element = $doc->getElementById('do_not_edit'); echo $element;

  Read the article

• Fun with casting and inheritance

  - by Vaccano

  NOTE: This question is written in a C# like pseudo code, but I am really going to ask which languages have a solution. Please don't get hung up on syntax. Say I have two classes: class AngleLabel: CustomLabel { public bool Bold; // code to allow the label to be on an angle } class Label: CustomLabel { public bool Bold; // Code for a normal label // Maybe has code not in an AngleLabel (align for example). } They both decend from this class: class CustomLabel: Control { protected bool Bold; } The bold field is exposed as public in the descended classes. No interfaces are available on the classes. Now, I have a method that I want to beable to pass in a CustomLabel and set the Bold property. Can this be done without having to 1) find out what the real class of the object is and 2) cast to that object and then 3) make seperate code for each variable of each label type to set bold. Kind of like this: public void SetBold(customLabel: CustomLabel) { AngleLabel angleLabel; NormalLabel normalLabel; if (angleLabel is AngleLabel ) { angleLabel= customLabel as AngleLabel angleLabel.Bold = true; } if (label is Label) { normalLabel = customLabel as Label normalLabel .Bold = true; } } It would be nice to maybe make one cast and and then set bold on one variable. What I was musing about was to make a fourth class that just exposes the bold variable and cast my custom label to that class. Would that work? If so, which languages would it work for? (This example is drawn from an old version of Delphi (Delphi 5)). I don't know if it would work for that language, (I still need to try it out) but I am curious if it would work for C++, C# or Java. If not, any ideas on what would work? (Remember no interfaces are provided and I can not modify the classes.) Any one have a guess?

  Read the article

• Validating JSP's and HTML Forms, Server-side or Client-side, or both?

  - by CitadelCSAlum

  I am aware that I can Google "HTML Form Validation" and would get a billion tutorials. I am well aware that I can use simple JavaScript to validate form input, but I have been told that this is not necessarily an efficient method. I have also heard that it is a best practice to validate both client and server-side code. OK! Well, What exactly does this mean besides writing code on both? Does it mean I do some with JavaScript and other with Servlet's or does it mean that I write identical validation methods on both? My real question is can anybody give me insight and direction as how to go about validation my HTML forms. I am using JSP's and Servlet's and I have tons of form validation to do. I have already done minor form validation with regex in Java, but want to figure out if Im heading in the right track before I write any more code. Only productive answers please, If I wanted negative feedback on how inexperienced I was, I would have gone to Reddit. Thanks!

  Read the article

• How do you slow down the output from a DOS command

  - by JW

  I have lots of experience of writing php scripts that are run in the context of a webserver and almost no epxerience of writing php scripts for CLI or GUI output. I have used the command line for linux but do not have much expereince with DOS. Lets say I have php script that is: <?php echo('Hello world'); for ($idx = 0 ; $idx < 100 ; $idx++ ) { echo 'I am line '. $idx . PHP_EOL; } Then, I run it in my DOS Command prompt: # php helloworld.php Now this will spurt out the output quckly and i have to scroll the DOS command window up to see the output. I want to see the output one 'screen full' at a time. How do you do that from the perspective of a DOS user? Furthermore, although this is not my main main question, I would be also interested in knowing how to make the php script 'wait for input' from the command prompt.

  Read the article

• iPhone: Helpful Classes or extended Subclasses which should have been in the SDK

  - by disp

  This is more a community sharing post than a real question. In my iPhone OS projects I'm always importing a helper class with helpful methods which I can use for about every project. So I thought it might be a good idea, if everyone shares some of their favorite methods, which should have been in everyones toolcase. I'll start with an extension of the NSString class, so I can make strings with dates on the fly providing format and locale. Maybe someone can find some need in this. @implementation NSString (DateHelper) +(NSString *) stringWithDate:(NSDate*)date withFormat:(NSString *)format withLocaleIdent:(NSString*)localeString{ NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; //For example @"de-DE", or @"en-US" NSLocale *locale = [[NSLocale alloc] initWithLocaleIdentifier:localeString]; [dateFormatter setLocale:locale]; // For example @"HH:mm" [dateFormatter setDateFormat:format]; NSString *string = [dateFormatter stringFromDate:date]; [dateFormatter release]; [locale release]; return string; } @end I'd love to see some of your tools.

  Read the article

• What does this structure actually do?

  - by LGTrader

  I found this structure code in a Julia Set example from a book on CUDA. I'm a newbie C programmer and cannot get my head around what it's doing, nor have I found the right thing to read on the web to clear it up. Here's the structure: struct cuComplex { float r; float i; cuComplex( float a, float b ) : r(a), i(b) {} float magnitude2( void ) { return r * r + i * i; } cuComplex operator*(const cuComplex& a) { return cuComplex(r*a.r - i*a.i, i*a.r + r*a.i); } cuComplex operator+(const cuComplex& a) { return cuComplex(r+a.r, i+a.i); } }; and it's called very simply like this: cuComplex c(-0.8, 0.156); cuComplex a(jx, jy); int i = 0; for (i=0; i<200; i++) { a = a * a + c; if (a.magnitude2() > 1000) return 0; } return 1; So, the code did what? Defined something of structure type 'cuComplex' giving the real and imaginary parts of a number. (-0.8 & 0.156) What is getting returned? (Or placed in the structure?) How do I work through the logic of the operator stuff in the struct to understand what is actually calculated and held there? I think that it's probably doing recursive calls back into the stucture float magnitude2 (void) { return return r * r + i * i; } probably calls the '*' operator for r and again for i, and then the results of those two operations call the '+' operator? Is this correct and what gets returned at each step? Just plain confused. Thanks!

  Read the article

• Quality of TFS 2008 merged code

  - by paologios

  Does the quality of code merged by TFS 2008 depend on the used programming language? I know merging in Java / Subversion, and merging a branch to its trunk usually does not create much conflicts. Now in my company, we use VB.NET. When I merge two files TFS does not always get code blocks right, e.g. does not find the right If..then / end if lines. To give you an example, I mean: File 2 is created as a branch of File 1. Both files were changed later, now I'm going to merge those files and am recieving conficts: The marked end-if lines (1) are detected as corresponding, meaning the added event handler Button1_Click is being deleted. Now I wonder if this behavior is by language (C# vs. VB.NET) or are other source control solutions just better than TFS? (And I really liked TFS up to now :) ) File 1: Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load If Not Page.IsPostBack Then Label1.Text = "Hello" Label2.Text = "World" End If End Sub Protected Sub Button2_Click(ByVal sender, ByVal e as System.EventArgs) Handles Button2.Click // .... If Page.IsValid Then Label3.Text = "Hello Button 2" End If // .... End Sub File 2 (Branch of File 1): Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load If Not Page.IsPostBack Then fillTableFromDatabase() End If // (1) End Sub Protected Sub Button1_Click(ByVal sender, ByVal e as System.EventArgs) Handles Button1.Click // do something here End Sub Protected Sub Button2_Click(ByVal sender, ByVal e as System.EventArgs) Handles Button2.Click // .... If Page.IsValid Then End If // (1) // .... End Sub

  Read the article

• removing phone number from a document.

  - by Grant Collins

  Hi, I've got a challenge that I am hoping that the SO community is able to help me with. I trying to parse a lot of html documents in my PHP application to remove personal details, such as names, addresses and phone numbers. I can remove most of these details without too much trouble, however the phone number is a real problem for me. My idea is to take the text from these documents and the use a regex to identify the phone numbers and replace them with another value such as 'xxxx'. I've got 2 regex that I am using one for UK landline numbers and one for UK cell/mobile numbers. However when I try and run them against the text it just returns an empty string. I am using the following preg_replace code: $pattens = array( '/^(((\+44\s?\d{4}|\(?0\d{4}\)?)\s?\d{3}\s?\d{3})|((\+44\s?\d{3}|\(?0\d{3}\)?)\s?\d{3}\s?\d{4})|((\+44\s?\d{2}|\(?0\d{2}\)?)\s?\d{4}\s?\d{4}))(\s?\#(\d{4}|\d{3}))?$/', '/^(\+44\s?7\d{3}|\(?07\d{3}\)?)\s?\d{3}\s?\d{3}$/' ); $replace = array('xxxxx', 'xxxxx'); //do the search for the numbers. $updatedContents = preg_replace($pattens, $replace, $htmlContents); At the moment this is causing me a lot of head scratching as I thought that I had this nailed, but at the moment I can't see what's wrong?? I am sure that it is something really simple. Thanks, Grant

  Read the article

• What's the best way of accessing a DRb object (e.g. Ruby Queue) from Scala (and Java)?

  - by Tom Morris

  I have built a variety of little scripts using Ruby's very simple Queue class, and share the Queue between Ruby and JRuby processes using DRb. It would be nice to be able to access these from Scala (and maybe Java) using JRuby. I've put together something Scala and the JSR-223 interface to access jruby-complete.jar. import javax.script._ class DRbQueue(host: String, port: Int) { private var engine = DRbQueue.factory.getEngineByName("jruby") private var invoker = engine.asInstanceOf[Invocable] engine.eval("require \"drb\" ") private var queue = engine.eval("DRbObject.new(nil, \"druby://" + host + ":" + port.toString + "\")") def isEmpty(): Boolean = invoker.invokeMethod(this.queue, "empty?").asInstanceOf[Boolean] def size(): Long = invoker.invokeMethod(this.queue, "length").asInstanceOf[Long] def threadsWaiting: Long = invoker.invokeMethod(this.queue, "num_waiting").asInstanceOf[Long] def offer(obj: Any) = invoker.invokeMethod(this.queue, "push", obj.asInstanceOf[java.lang.Object]) def poll(): Any = invoker.invokeMethod(this.queue, "pop") def clear(): Unit = { invoker.invokeMethod(this.queue, "clear") } } object DRbQueue { var factory = new ScriptEngineManager() } (It conforms roughly to java.util.Queue interface, but I haven't declared the interface because it doesn't implement the element and peek methods because the Ruby class doesn't offer them.) The problem with this is the type conversion. JRuby is fine with Scala's Strings - because they are Java strings. But if I give it a Scala Int or Long, or one of the other Scala types (List, Set, RichString, Array, Symbol) or some other custom type. This seems unnecessarily hacky: surely there has got to be a better way of doing RMI/DRb interop without having to use JSR-223 API. I could either make it so that the offer method serializes the object to, say, a JSON string and takes a structural type of only objects that have a toJson method. I could then write a Ruby wrapper class (or just monkeypatch Queue) to would parse the JSON. Is there any point in carrying on with trying to access DRb from Java/Scala? Might it just be easier to install a real message queue? (If so, any suggestions for a lightweight JVM-based MQ?)

  Read the article

• How can I unit test a PHP class method that executes a command-line program?

  - by acoulton

  For a PHP application I'm developing, I need to read the current git revision SHA which of course I can get easily by using shell_exec or backticks to execute the git command line client. I have obviously put this call into a method of its very own, so that I can easily isolate and mock this for the rest of my unit tests. So my class looks a bit like this: class Task_Bundle { public function execute() { // Do things $revision = $this->git_sha(); // Do more things } protected function git_sha() { return `git rev-parse --short HEAD`; } } Of course, although I can test most of the class by mocking git_sha, I'm struggling to see how to test the actual git_sha() method because I don't see a way to create a known state for it. I don't think there's any real value in a unit test that also calls git rev-parse to compare the results? I was wondering about at least asserting that the command had been run, but I can't see any way to get a history of shell commands executed by PHP - even if I specify that PHP should use BASH rather than SH the history list comes up empty, I presume because the separate backticks executions are separate terminal sessions. I'd love to hear any suggestions for how I might test this, or is it OK to just leave that method untested and be careful with it when the app is being maintained in future?

  Read the article

< Previous Page | 607 608 609 610 611 612 613 614 615 616 617 618  | Next Page >