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• Where and how to start on C# and .Net Framework ?

  - by Rachel

  Currently, I have been working as an PHP developer for approximately 1 year now and I want learn about C# and .Net Framework, I do not have any experience with .Net Framework and C# and also there is not firm basis as to why I am going for C# and .Net Framework vs Java or any other programming languages, this decision is mere on career point of view and job opportunities. So my question is about: Is my decision wise to go for C# and .Net Framework route after working for sometime as an PHP Developer ? What are the good resources which I can refer and learn from to get knowledge on C# and .NET Framework ? How should I go about learning on C# and .NET Framework ? What all technologies should I be learning OR have experience with to be considered as an C#/.Net Developer, I am mentioning some technologies, please add or suggest one, if am missing out any ? Technologies C#-THE LANGUAGE GUI APPLICATION DEVELOPMENT WINDOWS CONTROL LIBRARY DELEGATES DATA ACCESS WITH ADO.NET MULTI THREADING ASSEMBLIES WINDOWS SERVICES VB INTRODUCTION TO VISUAL STUDIO .NET WINDOWS CONTROL LIBRARY DATA ACCESS WITH ADO.NET ASP.NET WEB TECHNOLOGIES CONTROLS VALIDATION CONTROL STATE MANAGEMENT CACHING ASP.NET CONFIGURATION ADO.NET ASP.NET TRACING & SECURITY IN ASP.NET XMLPROGRAMMING WEB SERVICES CRYSTAL REPORTS SSRS (SQL Server Reporting Services) MS-Reports LINQ: NET Language-Integrated Query NET Language-Integrated Query LINQ to SQL: SQL Integration WCF: Windows Communication Foundation What Is Windows Communication Foundation? Fundamental Windows Communication Foundation Concepts Windows Communication Foundation Architecture WPF: Windows Presentation Foundation Getting Started (WPF) Application Development WPF Fundamentals What are your thoughts, suggestions on this and from Job and Market Perspective, what areas of C#/.Net Development should I put my focus on ? I know this is very subjective and long question but advice would be highly appeciated. Thanks.

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• Embedding Lua functions as member variables in Java

  - by Zarion

  Although the program I'm working on is in Java, answering this from a C perspective is also fine, considering that most of this is either language-agnostic, or happens on the Lua side of things. In the outline I have for the architecture of a game I'm programming, individual types of game objects within a particular class (eg: creatures, items, spells, etc.) are loaded from a data file. Most of their properties are simple data types, but I'd like a few of these members to actually contain simple scripts that define, for example, what an item does when it's used. The scripts will be extremely simple, since all fundamental game actions will be exposed through an API from Java. The Lua is simply responsible for stringing a couple of these basic functions together, and setting arguments. The question is largely about the best way to store a reference to a specific Lua function as a member of a Java class. I understand that if I store the Lua code as a string and call lua_dostring, Lua will compile the code fresh every time it's called. So the function needs to be defined somehow, and a reference to this specific function wrapped in a Java function object. One possibility that I've considered is, during the data loading process, when the loader encounters a script definition in a data file, it extracts this string, decorates the function name using the associated object's unique ID, calls lua_dostring on the string containing a full function definition, and then wraps the generated function name in a Java function object. A function declared in script run with lua_dostring should still be added to the global function table, correct? I'm just wondering if there's a better way of going about this. I admit that my knowledge of Lua at this point is rather superficial and theoretical, so it's possible that I'm overlooking something obvious.

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• iPhone: variable type returned by yajl

  - by Luc

  Hello, I'm quite new to iphone programming and I want to do the following stuff: get data from a JSON REST web server parse the received data using YAJL Draw a graph with those data using core-plot So, 1th item is fine, I use ASIHttpRequest which runs as espected 3rd is almost fine (I still have to learn how to tune core-plot). The problem I have is regarding 2nd item. I use YAJL as it seems to be the faster parser, so why not give it a try :) Here is the part of code that gets the data from the server and parse them: // Get server data response_data = [request responseData]; // Parse JSON received self.arrayFromData = [response_data yajl_JSON]; NSLog(@"Array from data: %@", self.arrayFromData); The parsing works quite well in fact, the NSLog output is something like: 2010-06-14 17:56:35.375 TEST_APP[3733:207] Array from data : { data = ( { val = 1317; date = "2010-06-10T15:50:01+02:00"; }, { val = 1573; date = "2010-06-10T16:20:01+02:00"; }, ........ { val = 840; date = "2010-06-11T14:50:01+02:00"; }, { val = 1265; date = "2010-06-11T15:20:01+02:00"; } ); from = "2010-06-10T15:50:01+02:00"; to = "2010-06-11T15:20:01+02:00"; max = "2590"; } According to th yajl-objc explanations http://github.com/gabriel/yajl-objc, the parsing returns a NSArray... The thing is... I do not know how to get all the values from it as for me it looks more like a NSDictionary than a NSArray... Could you please help ? Thanks a lot, Luc edit1: it happens that this object is actually a NSCFDictionary (!), I am still not able to get value from it, when I try the objectFromKey method (that should work on a Dictionary, no ?) it fails.

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• WordPerfect programmers refusing to use anything but assembler

  - by Totophil

  There is a version (popularised by Joel Spolsky) attributing the demise of WordPerfect to a refusal of its programmers to use anything but assembler that led to delay of the first WPwin release and as result eventually to losing the all important battle with Microsoft. There are a few references to programming work being done using assembler in the autobiographical book "Almost Perfect" by W. E. Pete Peterson who used to have a major influence at running the corporation. But these references go back to early 80's when WordPerfect was trying to gain a significant market share by defeating WordStar and not early nineties when the battle with MS took place. I am looking for a second independent source to confirm the assumption. Maybe someone who worked for WordPerfect Corporation at a time, who was close to the company, or had a chance to see the source could clarify the issue. Your help is much appreciated, thanks! Please note that this question is not about any other theories or reasons behind WordPerfect demise. I really just need to clarify whether they used assembler as a primary language for WPwin and (as a bonus really) whether there were discussions held within the corporation about assembler being the right choice. Concisely: Did WPCorp use assembler as a primary language for WPwin? Were discussions held at a time amongst WP Corp staff about assembler being the right choice (was it management or programmers decision)?

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• Zend Framework or CakePHP?

  - by gorzan

  My group is going to attempt to build a new CMS from scratch, designed to serve the needs of our organization. It should be noted that none of us have any formal programming education, but we've picked up this and that from developing different websites, among others the one our community uses now. We've decided to program the new CMS in PHP, with total MVC seperation. Not wanting to re-invent all the little cogs and wheels needed for such a potentially large project as this, we've been looking into using a PHP framework, and some googling and blog-surfing landed us in a discussion: Zend vs Cake? Anyone have any useful input here? Also, any other tips for embarking on this project would be appreciated. (Except for suggestions for existing CMSes, we know they're out there.) EDIT: It seems I was a bit unclear. None of us are NEW to PHP - in fact, we all have fairly extensive experience from previous projects, including the current solution our community's website runs on which we built ourselves. The decision to not use an existing CMS is a very informed one, so although I appreciate all the good suggestions we really are going to do this ourselves. So. Zend vs Cake?

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• Why is cell phone software is still so primitive?

  - by Tomislav Nakic-Alfirevic

  I don't do mobile development, but it strikes me as odd that features like this aren't available by default on most phones: full text search: searches all address book contents, messages, anything else being a plus better call management: e.g. a rotating audio call log, meaning you always have the last N calls recorded for your listening pleasure later (your little girl just said her first "da-da" while you were on a business trip, you had a telephone job interview, you received complex instructions to do something etc.) bluetooth remote control (like e.g. anyRemote, but available by default on a bluetooth phone) no multitasking capabilities worth mentioning and in general no e.g. weekly software updates, making the phone much more usable (even if it had to be done over USB, rather than over the network). I'm sure I was dumbfounded by the lack or design of other features as well, but they don't come to mind right now. To clarify, I'm not talking about smartphones here: my plain, 2-year old phone has a CPU an order of magnitude faster than my first PC, about as much storage space and it's ridiculous how bad (slow, unwieldy) the software is and it's not one phone or one manufacturer. What keeps the (to me) obvious software functionality vacuum on a capable hardware platform from being filled up?

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• Animation not playing

  - by Tate Allen

  Hello again, I didn't say this last time but I am relatively new to iPhone programming and extremely new to iPhone game development so bear with me. In my game, when I tilt the device, the character moves and faces the correct direction, but does not animate. I am using an animated UIImageView. Here is the code: float newX = character.center.x + (accel.x * 12); if (newX 30 && newX < 290) character.center = CGPointMake(newX, character.center.y); if (accel.x < 0) { NSArray *imgArray = [[NSArray alloc] initWithObjects: [UIImage imageNamed:@"run3left.png"], [UIImage imageNamed:@"run1left.png"], [UIImage imageNamed:@"run2left.png"], [UIImage imageNamed:@"run1left.png"], nil]; character.animationImages = imgArray; character.animationDuration = 0.5; character.contentMode = UIViewContentModeBottomLeft; [self.view addSubview:character]; [character startAnimating]; } if (accel.x > 0) { NSArray *imgArray = [[NSArray alloc] initWithObjects: [UIImage imageNamed:@"run3.png"], [UIImage imageNamed:@"run1.png"], [UIImage imageNamed:@"run2.png"], [UIImage imageNamed:@"run1.png"], nil]; character.animationImages = imgArray; character.animationDuration = 0.5; character.contentMode = UIViewContentModeBottomLeft; [self.view addSubview:character]; [character startAnimating]; } }

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• Writing language converter in ANTLR

  - by Stefan

  I'm writing a converter between some dialects of the same programming language. I've found a grammar on the net - it's complex and handles all the cases. Now I'm trying to write the appropriate actions. Most of the input is just going to be rewritten to output. What I need to do is parse function calls, do my magic (rename function, reorder arguments, etc) and write it. I'm using AST as output. When I come across a function call, I build a custom object structure (from classes defined in my target language), call the appropriate function and I have a string that represents the transformed function that I want to get. The problem is, what I'm supposed to do with that string? I'd like to replace the .text attribute of the enclosing rule, but setText() is only available on lexer rules and the rule's .text attribute is read-only. How to solve this problem? program : statement_list { output = $statement_list.text; } ; //... statement : expression_statement // ... ; expression_statement : function_call // ... ; function_call : ID '(' { /* build the object, assign name */ Function function = new Function(); //... } ( arg1 = expression { /* add first parameter */ } ( ',' arg2 = expression { /* add the rest of parameters */ } )* )? ')' { /* convert the function call */ string converted = Tools.Convert(function); // $setText(converted); // doesn't work // $functionCall.text = converted; // doesn't work } ;

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• why does b'(and sometimes b' ') show up when I split some HTML source[Python]

  - by Oliver

  I'm fairly new to Python and programming in general. I have done a few tutorials and am about 2/3 through a pretty good book. That being said I've been trying to get more comfortable with Python and proggramming by just trying things in the std lib out. that being said I have recently run into a wierd quirk that I'm sure is the result of my own incorrect or un-"pythonic" use of the urllib module(with Python 3.2.2) import urllib.request HTML_source = urllib.request.urlopen(www.somelink.com).read() print(HTML_source) when this bit is run through the active interpreter it returns the HTML source of somelink, however it prefixes it with b' for example b'<HTML>\r\n<HEAD> (etc). . . . if I split the string into a list by whitespace it prefixes every item with the b' I'm not really trying to accomplish something specific just trying to familiarize myself with the std lib. I would like to know why this b' is getting prefixed also bonus -- Is there a better way to get HTML source WITHOUT using a third party module. I know all that jazz about not reinventing the wheel and what not but I'm trying to learn by "building my own tools" Thanks in Advance!

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• Elegant Algorithm for Parsing Data Stream Into Record

  - by Matt Long

  I am interfacing with a hardware device that streams data to my app over Wifi. The data is streaming in just fine. The data contains a character header (DATA:) that indicates a new record has begun. The issues is that the data I receive doesn't necessarily fall on the header boundary, so I have to capture the data until what I've captured contains the header. Then, everything that precedes the header goes into the previous record and everything that comes after it goes into a new record. I have this working, but wondered if anyone has done this before and has a good computer-sciencey way to solve the problem. Here's what I do: Convert the NSData of the current read to an NSString Append the NSString to a placeholder string Check placeholder string for the header (DATA:). If the header is not there, just wait for the next read. If the header exists, append whatever precedes it to a previous record placeholder and hand that placeholder off to an array as a complete record that I can further parse into fields. Take whatever shows up after the header and place it in the record placeholder so that it can be appended to in the next read. Repeat steps 3 - 5. Let me know if you see any flaws with this or have a suggestion for a better way. Seems there should be some design pattern for this, but I can't think of one. Thanks.

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• Formatting Parameters for Ajax POST request to Rails Controller - for jQuery-UI sortable list

  - by Hung Luu

  I'm using the jQuery-UI Sortable Connected Lists. I'm saving the order of the connected lists to a Rails server. My approach is to grab the list ID, column ID and index position of each list item. I want to then wrap this into an object that can be passed as a parameter back to the Rails Controller to be saved into the database. So ideally i'm looking to format the parameter like this: Parameters: {"Activity"=>[{id:1,column:2,position:1},{id:2,column:2,position:2} ,...]} How do I properly format my parameters to be passed in this Ajax POST request? Right now, with the approach below, I'm passing on Parameters: {"undefined"=>""} This is my current jQuery code (Coffeescript) which doesn't work: jQuery -> $('[id*="day"]').sortable( connectWith: ".day" placeholder: "ui-state-highlight" update: (event, ui) -> neworder = new Array() $('[id*="day"] > li').each -> column = $(this).attr("id") index = ui.item.index() + 1 id = $("#" + column + " li:nth-child(" + index + ") ").attr('id') passObject={} passObject.id = id passObject.column = column passObject.index = index neworder.push(passObject) alert neworder $.ajax url: "sort" type: "POST" data: neworder ).disableSelection() My apologies because this seems like a really amateur question but I'm just getting started with programming jQuery and Javascript.

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• Is there the equivalent of cloud computing for modems?

  - by morpheous

  I asked this question on SF, and someone recommended that I ask it here - (I don't think I have enough points to move a question from SF to SO - and in any case, I don't know how to do it - so here is the question again): I am interested in the concept of PAAS (platform as a service). However, all talk about SAAS/PAAS seems to focus on only the computer itself - not its peripherals. Is it possible to 'outsource' modems as a resource - so that an app running remotely can pump data to a modem in the cloud? As a bit of background to the question, a group of us are thinking of starting a company that offers similar services to companies like twilio etc - but I want to 'outsource' both the computing hardware (thats PAAS - the easy bit) and the modems (thats what I cant seem to find any info on). Does anyone know if modems can be bundled as part of a PAAS service? - alternatively, is there a way that an application running on one computer can communicate (i.e. pump data) to a remote modem residing on another machine?. I assume I can come up with some protocol over UDP or TCP - but there is no point reinventing the wheel - if such a protocol like that already exists (or if it some open source software allows one to do this). Any suggestions on how to solve this problem?

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• Invert a string: Recursion vs iteration in javascript

  - by steweb

  Hi all, one month ago I've been interviewed by some google PTO members. One of the questions was: Invert a string recursively in js and explain the running time by big O notation this was my solution: function invert(s){ return (s.length > 1) ? s.charAt(s.length-1)+invert(s.substring(0,s.length-1)) : s; } Pretty simple, I think. And, about the big-o notation, I quickly answered O(n) as the running time depends linearly on the input. - Silence - and then, he asked me, what are the differences in terms of running time if you implement it by iteration? I replied that sometimes the compiler "translate" the recursion into iteration (some programming language course memories) so there are no differences about iteration and recursion in this case. Btw since I had no feedback about this particular question, and the interviewer didn't answer "ok" or "nope", I'd like to know if you maybe agree with me or if you can explain me whether there could be differences about the 2 kind of implementations. Thanks a lot and Regards!

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• Suitable ESXi Spec

  - by Canacourse

  Finally I have some money to buy a new server and replace the one I have been using for 10 years. Im thinking of running ESXi on the new server. And intend to use it as follows; One W2008 R2 Guest running Exchange, File store, SVN and an accounting application for day to day running of the company. Multiple Guest VMs W2K, XP, Vista & WIN7 that were setup for testing in-house & real customer images also for testing. Probably Two Server Guest Os's W2003 & W2008 running at the same time again for testing. One Guest VM for builds & Continuous integration. Possibly one Guest running W220R2 for a customer website (Portal) This server will have to last another 10 years so I want to get the spec right. Althought I am clear on the memory and disk requirments I am not so clear on the processor(s). Im thinking of 2 Quadcore processors but welcome advice on this. Proposed Spec 10GB Ram 2TB Sata Drives (Hardware Raid 1) 2 Processors (TBC) Normally 3 Server VM's will running concurrently and the other VMs will be started as required. Max expected VMs running about 7. Max users = 4. TIA..

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• how to create nettcpbinding of this custombinding

  - by evgeni

  I am new at wcf programming model and i want to use nettcpbinding. before i ask my question below is my custom binding : <customBinding> <binding name="basic"> <security authenticationMode="UserNameForCertificate"/> <binaryMessageEncoding/> <httpsTransport/> </binding> </customBinding> when i create a service reference using a simple console application it finds a certificate and ask me to use it.and this way i can use the webservice ... but when i change binding to nettcpbinding with TransportWithMessageCredential the service is looking for certificate and could not find it like this : </binding> </netTcpBinding> ServiceCertificate.SetCertificate(StoreLocation.LocalMachine, StoreName.My, X509FindType.FindByIssuerName, "Contoso.com"). at this point i use a customnamevalidator and i do it programmatically. so why when i use nettcpbinding with TransportWithMessageCredential why is SetCertificate could not find the installed certificate ? am i missed something ? or do i have to ad something? thanks .

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• use exec for dsadd

  - by Daryl Gill

  I'm Programming on a Windows Server 2008 and I wish to have a WebUI to interact with the domains active directory. One of my main problems is this that i'm using dsadd from a HTML form but this is no succeeding. I know my command is correct, I have tested it out on the Servers Command line My Code is As Below: if (isset($_POST['Submit'])) { $DesiredUsername = $_POST['DesiredUsername']; $DesiredPassword = $_POST['DesiredPassword']; $DU = "{$DesiredUsername}"; // Desired Username $OU = "PHPCreatedUsers"; // Domain OU $DC1 = "slayerserv"; // Domain Part one $DC2 = "local"; // Domain Part Two $PWD = "{$DesiredPassword}"; // Password $ExecScript = 'dsadd user cn=$DesiredUsername,cn=PHPCreatedUsers,dc=slayerserv,dc=local -disabled no -pwd $DesiredPassword -mustchpwd yes'; exec($ExecScript, $output); mysql_query("INSERT INTO addedusers (`ID`, `DU`, `OU`, `DC1`, `DC2, `PWD`) VALUES ('', '$DU', '$OU', '$DC1', '$DC2', '$PWD')"); echo "<br><br>"; print_r($output); # echo "User: $DesiredUsername Has been Created"; } When I print_r($output); it Returns a blank array: Array ( ) Could anyone provide me with a solution or point me in the right direction? ++++ Below is a working example of my usage of exec $Script = 'ping 127.0.0.1 -n 1'; exec($Script, $Output); print_r($Output); print_r($Output); Gives: Array ( [0] = [1] = Pinging 127.0.0.1 with 32 bytes of data: [2] = Reply from 127.0.0.1: bytes=32 time<1ms TTL=128 [3] = [4] = Ping statistics for 127.0.0.1: [5] = Packets: Sent = 1, Received = 1, Lost = 0 (0% loss), [6] = Approximate round trip times in milli-seconds: [7] = Minimum = 0ms, Maximum = 0ms, Average = 0ms )

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• Only last row in method execute (Objective-C)

  - by Emil

  First I want to apologize for my lack of knowledge in programming in general. I am in the way of learning and have discovered that this site is a huge compliment for me of doing so. I have created a program with three UITextField(thePlace,theVerb,theOutput) and two UITextView where one of the textviews(theOutput) take the text from the other textview(theTemplate) and replaces some strings with the text entered in the textfields. When I click a button it triggers the method createStory that is listed below. This works fine with one exception. The text in the output only changes the string 'number' to the text in the textfield. However if I change the order in the method to replace 'place','number','verb' only the verb is changed, not the number. Im sure this is some sort of easy fix but I can't find it. Can some of you help me with my troubleshooting? - (IBAction)createStory:(id)sender { theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<place>" withString:thePlace.text]; theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<verb>" withString:theVerb.text]; theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<number>" withString:theNumber.text]; } Many thanks // Emil

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• Suggestions for entering mobile development -- pure iPhone SDK, Andorid SDK. Mono Touch or Titanium?

  - by Tom Cabanski

  I am entering mobile development. I have been working primarily in .NET since 1.0 came out in beta. Before that, I was mostly a C++ and Delphi guy and still dabble in C++ from time to time. I do web apps quite a bit so I am reasonably proficient with Javascript, JQuery and CSS. I have also done a few Java applications. I started web programming with CGI and live mostly in the ASP.NET MVC world these days. I am trying to decide on which platform/OS and tool to select. I am concerned with the size of the market available for my applications as well as the marketibility of the skills I will pick up. The apps I have in mind would work on both phones and pads. Some aspects of what I have in mind will play better on the bigger screens that will be available on pads. Here are the options I am considering: Apple iPhone/iPad using pure Apple SDK (Objective-C) Apple iPhone/iPad using Mono Touch (C#) Android using pure Android SDK (Java) Multiple platforms using something like Titanium to generate native apps from web technologies (HTML, CSS and Javascript) Multiple platforms using HTML5 web applications that run in the browser (HTML, CSS and Javascript). Which option would you choose? Do you have a different suggestion? What are the pros and cons?

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• Entity Framework 4 / POCO - Where to start?

  - by Basiclife

  Hi, I've been programming for a while and have used LINQ-To-SQL and LINQ-To-Entities before (although when using entities it has been on a Entity/Table 1-1 relationship - ie not much different than L2SQL) I've been doing a lot of reading about Inversion of Control, Unit of Work, POCO and repository patterns and would like to use this methodology in my new applications. Where I'm struggling is finding a clear, concise beginners guide for EF4 which doesn't assume knowledge of EF1. The specific questions I need answered are: Code first / model first? Pros/cons in regards to EF4 (ie what happens if I do code first, change the code at a later date and need to regenerate my DB model - Does the data get preserved and transformed or dropped?) Assuming I'm going code-first (I'd like to see how EF4 converts that to a DB schema) how do I actually get started? Quite often I've seen articles with entity diagrams stating "So this is my entity model, now I'm going to ..." - Unfortunately, I'm unclear if they're created the model in the designer, saved it to generate code then stopped any further auto-code generation -or- They've coded (POCO)? classes and the somehow imported them into the deisgner view? I suppose what I really need is an understanding of where the "magic" comes from and how to add it myself if I'm not just generating an EF model directly from a DB. I'm aware the question is a little vague but I don't know what I don't know - So any input / correction / clarification appreciated. Needless to say, I don't expect anyone to sit here and teach me EF - I'd just like some good tutorials/forums/blogs/etc. for complete entity newbies Many thanks in advance

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• Loading UITableView form UIView

  - by Amarpreet

  Hi Guys, I am working on navigation based application in which i can navigate to many views starting from default UITableView which is starting view in application template. I have added another UIView and added tableView control on that UIView. I am calling that view form one of the many views on a button click. Its showing the view but not populating the data in the table. And I also want to handle the event when user taps on the cell of the table of that view. Below is the Code I am using on button click: if(self.lstView == nil) { ListViewController *viewController = [[ListViewController alloc] initWithNibName:@"ListViewController" bundle:nil]; self.lstView = viewController; [viewController release]; } [self.navigationController pushViewController:lstView animated:YES]; self.lstView.title = @"Select";//@"System"; [self.lstView.tblList.dataSource fillList]; Below is the fillList function code: -(NSArray *)fillList { NSArray *tempArray = [[[NSArray alloc] initWithObjects:@"Item 1" , @"Item 2" , nil]autorelease]; return tempArray; } I am pretty new in Iphone programming and don't have much understanding. Helping with detailed description and code will be highly appreciated. Thanks.

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• Cache consistency & spawning a thread

  - by Dave Keck

  Background I've been reading through various books and articles to learn about processor caches, cache consistency, and memory barriers in the context of concurrent execution. So far though, I have been unable to determine whether a common coding practice of mine is safe in the strictest sense. Assumptions The following pseudo-code is executed on a two-processor machine: int sharedVar = 0; myThread() { print(sharedVar); } main() { sharedVar = 1; spawnThread(myThread); sleep(-1); } main() executes on processor 1 (P1), while myThread() executes on P2. Initially, sharedVar exists in the caches of both P1 and P2 with the initial value of 0 (due to some "warm-up code" that isn't shown above.) Question Strictly speaking – preferably without assuming any particular CPU – is myThread() guaranteed to print 1? With my newfound knowledge of processor caches, it seems entirely possible that at the time of the print() statement, P2 may not have received the invalidation request for sharedVar caused by P1's assignment in main(). Therefore, it seems possible that myThread() could print 0. References These are the related articles and books I've been reading. (It wouldn't allow me to format these as links because I'm a new user - sorry.) Shared Memory Consistency Models: A Tutorial hpl.hp.com/techreports/Compaq-DEC/WRL-95-7.pdf Memory Barriers: a Hardware View for Software Hackers rdrop.com/users/paulmck/scalability/paper/whymb.2009.04.05a.pdf Linux Kernel Memory Barriers kernel.org/doc/Documentation/memory-barriers.txt Computer Architecture: A Quantitative Approach amazon.com/Computer-Architecture-Quantitative-Approach-4th/dp/0123704901/ref=dp_ob_title_bk

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• UITableView madness

  - by kesrut

  Hello, I'm new to iPhone application development. I'm trying to understand how to use UITableView. I'm wrote simple code: - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return 1 ; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *MyIdentifier = @"MyIdentifier"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:MyIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:MyIdentifier] autorelease]; } cell.textLabel.text = @"Hello"; return cell; } UITable shows content, but if i'm drag table contents my application terminates. You can see video: http://www.youtube.com/watch?v=TucTVJVhSD0 I tried to everything with array: - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1 ; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return [hello count] ; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *MyIdentifier = @"MyIdentifier"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:MyIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:MyIdentifier] autorelease]; } cell.textLabel.text = [hello objectAtIndex:indexPath.row]; return cell; } - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { [tableView deselectRowAtIndexPath:indexPath animated:NO]; NSLog(@"Selected") ; } - (void) awakeFromNib { hello = [[NSArray alloc] initWithObjects:@"hello", @"world", @"end", nil]; } // Implement viewDidLoad to do additional setup after loading the view, typically from a nib. - (void)viewDidLoad { [super viewDidLoad]; } Content is shown and if I'm selecting item i'm getting: [Session started at 2010-03-16 19:21:48 +0200.] 2010-03-16 19:21:52.295 ViewTest[1775:207] * -[ViewTestViewController respondsToSelector:]: message sent to deallocated instance 0x3911ec0 I'm total new to iPhone programming. And as i see everything i do - i'm just getting application terminated ..

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• _Painless_ integration of Eclipse with Vim?

  - by Adnan

  Hi, Has anyone managed to get Vim integrated into Eclipse painlessly? I just want to use Vim for the editor while retaining the general Eclipse interface. I have tried using Eclim plugin but the editor seemed to crash more often than work (the site said that the editor replacement functionality is still beta). On the flip side, is there any IDE which matches Eclipse's functionality -- mainly the integration with SVN, ant, etc. -- and is also able to use Vim? I mostly use eclipse for SAS SCL, Java and Javascript programming and find the eclipse editor too "mouse-y". I'd also like, in a perfect world, to use vimdiff as a diff viewer for SVN (we use TortoiseSVN) while checking for diffs or conflicts during merge etc. I admit I havent spent a lot of time trying to get these things to work. I feel guilty about spending too much time on potential wild-goose-chases while my other team members are working away at their code, perfectly content with all that eclipse has to offer. Edit: Just found this while desperately browsing around: Vim plugin.. Any experience using this? Its saturday afternoon in Kiwi land, so I'll try it later and update if no one has an opinion. From the claims on the site, it sounds perfect.

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• Does LaTeX have an array data structure?

  - by drasto

  Are there arrays in LaTeX? I don't mean the way to typeset arrays. I mean arrays as the data structure in LaTeX/TeX as a "programming language". I need to store a number of vbox-es or hbox-es in an array. It may be something like "an array of macros". More details: I have an environment that should typeset songs. I need to store some songs' paragraphs given as arguments to my macro \songparagraph (so I will not typeset them, just store those paragraphs). As I don't know how many paragraphs can be in one particular song I need an array for this. When the environment is closed, all the paragraphs will be typeset - but they will be first measured and the best placement for each paragraph will be computed (for example, some paragraphs can be put one aside the other in two columns to make the song look more compact and save some space). Any ideas would be welcome. Please, if you know about arrays in LaTeX, post a link to some basic documentation, tutorial or just state basic commands.

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• Getting started with massive data

  - by Max

  I'm a math guy and occasionally do some statistics/machine learning analysis consulting projects on the side. The data I have access to are usually on the smaller side, at most a couple hundred of megabytes (and almost always far less), but I want to learn more about handling and analyzing data on the gigabyte/terabyte scale. What do I need to know and what are some good resources to learn from? Hadoop/MapReduce is one obvious start. Is there a particular programming language I should pick up? (I primarily work now in Python, Ruby, R, and occasionally Java, but it seems like C and Clojure are often used for large-scale data analysis?) I'm not really familiar with the whole NoSQL movement, except that it's associated with big data. What's a good place to learn about it, and is there a particular implementation (Cassandra, CouchDB, etc.) I should get familiar with? Where can I learn about applying machine learning algorithms to huge amounts of data? My math background is mostly on the theory side, definitely not on the numerical or approximation side, and I'm guessing most of the standard ML algorithms don't really scale. Any other suggestions on things to learn would be great!

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