Search Results

Search found 12674 results on 507 pages for 'programming competitions'.

Page 447/507 | < Previous Page | 443 444 445 446 447 448 449 450 451 452 453 454  | Next Page >

• UITableView and UITableCellView, how does this work with core plot ?

  - by Luc

  Hello, I'm very new to iPhone programming, and I'm currently following tutos to understand the whole thing. I've been able to do what I needed (retrive data from a JSON http server, parse them with YAJL and plot the data in core plot). I have done this in a "simple" view where I have added a UILayerHostingView as requested by core-plot. I am now trying to follow this tuto: http://blogs.remobjects.com/blogs/mh/2010/01/26/p973 but I am missing the first part regarding the views... My understanding is that I need to create a view with a UITableView first. Then add a UITableCellView to make the first cell be able to contain the graph ? Is this right ? Where does the method "(id)initWithStyle:(UITableViewCellStyle)style" come from ? For my needs, only the first cell needs to contain a graph, I will put some other info in the other cells. As for now, I have created a new GraphListViewController, in the corresponding view I have added a listview but I do not see any auto generated methods regading cell customisation ? Do I need to implements DataSource in this controller and manually add some customisation methods ? Do I need to add a UITagbleViewCell to this UITableViewTable within IB ? Hope I am not getting to confusing... Thanks a lot for your help, Best Regards, Luc

  Read the article

• Manually Writing the HTML in TWebBrowser Pt. 2

  - by nomad311

  As the name suggests this is a continuation (sort of) of http://stackoverflow.com/questions/2784679/manually-writing-the-html-in-twebbrowser This time around I'm trying to add some auto-refresh logic to the HTML I get. I have pieced together an approach from several sources (see below). In short, I am trying to locate the title node and add a meta node after it (in the HTML head node). But, I get an access violation. Here is the source: iHtmlDoc := IHTMLDocument3(WebBrowser1.Document); iHtmlEleTitle := IHTMLElement2(iHtmlDoc.getElementsByName('title').item(0, 0)); iHtmlEle := IHTMLElement2(IHTMLDocument2(iHtmlDoc).createElement(Format('<meta http-equiv="refresh" content="%d">', [1]))); iHtmlEleTitle.insertAdjacentElement('afterEnd', IHTMLElement(iHtmlEle)); And A (technically not functionally) different way of doing it ...casting is slightly different here: IHTMLElement2(IHtmlDocument3(WebBrowser1.Document).getElementsByName('title').item(0, 0)).insertAdjacentElement('afterEnd', IHTMLDocument2(WebBrowser1.Document).createElement(Format('<meta http-equiv="refresh" content="%d">', [VPI_ISSUANCE_AUTO_RELOAD]))); Again all I get from Delphi is a access exception, and I fished through MSDN documentation on it, but now I'm hoping someone out there has gone through the same and has some insight. Any help? Sources (I think this is all of them): http://webdesign.about.com/od/metataglibraries/a/aa080300a.htm (auto-reload) http://delphi.about.com/od/adptips2005/qt/webbrowserhtml.htm (web browser document as an HTML document) http://msdn.microsoft.com/en-us/library/system.windows.forms.htmlelement.insertadjacentelement(VS.80).aspx (GetElementsByName) http://www.experts-exchange.com/Web_Development/Components/ActiveX/Q_26131034.html (insertAdjacentElement) http://www.experts-exchange.com/Programming/Languages/Pascal/Delphi/Q_23407977.html (GetElementsByName)

  Read the article

• Need help choosing database server

  - by The Pretender

  Good day everyone. Recently I was given a task to develop an application to automate some aspects of stocks trading. While working on initial architecture, the database dilemma emerged. What I need is a fast database engine which can process huge amounts of data coming in very fast. I'm fairly experienced in general programming, but I never faced a task of developing a high-load database architecture. I developed a simple MSSQL database schema with several many-to-many relationships during one of my projects, but that's it. What I'm looking for is some advice on choosing the most suitable database engine and some pointers to various manuals or books which describe high-load database development. Specifics of the project are as follows: OS: Windows NT family (Server 2008 / 7) Primary platform: .NET with C# Database structure: one table to hold primary items and two or three tables with foreign keys to the first table to hold additional information. Database SELECT requirements: Need super-fast selection by foreign keys and by combination of foreign key and one of the columns (presumably DATETIME) Database INSERT requirements: The faster the better :) If there'll be significant performance gain, some parts can be written in C++ with managed interfaces to the rest of the system. So once again: given all that stuff I just typed, please give me some advice on what the best database for my project is. Links or references to some manuals and books on the subject are also greatly appreciated. EDIT: I'll need to insert 3-5 rows in 2 tables approximately once in 30-50 milliseconds and I'll need to do SELECT with 0-2 WHERE clauses queries with similar rate.

  Read the article

• What's it like being a financial programmer?

  - by Mike

  As a student who's done an internship at a Silicon Valley company(non-financial), I'm curious to know what it's like working for a financial company doing software development. I'd expect the hours to be longer, and the pay to be higher. Specifically, I have the following questions: What's the work/life balance really like? Are you expected to work 80 hours a week most weeks? For those who have worked in non-financial software engineering jobs, how does being a financial software engineer compare in terms of work/life balance? How much does it pay? I'm curious as to starting(i.e. just got a BS) pay, as well as "top out" pay. (I'd prefer concrete numbers - ballpark is fine). Also, bonuses would be useful information. What jobs do financial programmers typically have? Are most just general software engineers, or do people typically have very specialized(i.e. AI or systems) backgrounds? Also, do most programmers have PhDs? Are programmers typically required to be at work, or are financial companies generally flexible about letting programmers work from home? When at work, do programmers have to dress formally? What are the technology environments like? Are finance companies using state-of-the-art hardware and software, or are they generally more conservative in upgrading their equipment? What programming languages are typically used? If VBA(shudder) is used, is it a large part of a finance company's workflow? If you could turn back the clock, would you still be a financial programmer? I'm going to keep this post open a little bit longer to get some more responses.

  Read the article

• Solving problems involving more complex data structures with CUDA

  - by Nils

  So I read a bit about CUDA and GPU programming. I noticed a few things such that access to global memory is slow (therefore shared memory should be used) and that the execution path of threads in a warp should not diverge. I also looked at the (dense) matrix multiplication example, described in the programmers manual and the nbody problem. And the trick with the implementation seems to be the same: Arrange the calculation in a grid (which it already is in case of the matrix mul); then subdivide the grid into smaller tiles; fetch the tiles into shared memory and let the threads calculate as long as possible, until it needs to reload data from the global memory into shared memory. In case of the nbody problem the calculation for each body-body interaction is exactly the same (page 682): bodyBodyInteraction(float4 bi, float4 bj, float3 ai) It takes two bodies and an acceleration vectors. The body vector has four components it's position and the weight. When reading the paper, the calculation is understood easily. But what is if we have a more complex object, with a dynamic data structure? For now just assume that we have an object (similar to the body object presented in the paper) which has a list of other objects attached and the number of objects attached is different in each thread. How could I implement that without having the execution paths of the threads to diverge? I'm also looking for literature which explains how different algorithms involving more complex data structures can be effectively implemented in CUDA.

  Read the article

• SQL View with Data from two tables

  - by Alex

  Hello! I can't seem to crack this - I have two tables (Persons and Companies), and I'm trying to create a view that: 1) shows all persons 2) also returns companies by themselves once, regardless of how many persons are related to it 3) orders by name across both tables To clarify, some sample data: (Table: Companies) Id Name 1 Banana 2 ABC Inc. 3 Microsoft 4 Bigwig (Table: Persons) Id Name RelatedCompanyId 1 Joe Smith 3 2 Justin 3 Paul Rudd 4 4 Anjolie 5 Dustin 4 The output I'm looking for is something like this: Name PersonName CompanyName RelatedCompanyId ABC Inc. NULL ABC Inc. NULL Anjolie Anjolie NULL NULL Banana NULL Banana NULL Bigwig NULL Bigwig NULL Dustin Dustin Bigwig 4 Joe Smith Joe Smith Microsoft 3 Justin Justin NULL NULL Microsoft NULL Microsoft NULL Paul Rudd Paul Rudd Bigwig 4 As you can see, the new "Name" column is ordered across both tables (the company names appear correctly in between the person names), and each company appears exactly once, regardless of how many people are related to it. Can this even be done in SQL?! P.S. I'm trying to create a view so I can use this later for easy data retrieval, fulltext indexing and make the programming side simpler by just querying the view.

  Read the article

• C++ LNK2019 error with constructors and destructors in derived classes

  - by BLH

  I have two classes, one inherited from the other. When I compile, I get the following errors: 1Entity.obj : error LNK2019: unresolved external symbol "public: __thiscall Utility::Parsables::Base::Base(void)" (??0Base@Parsables@Utility@@QAE@XZ) referenced in function "public: __thiscall Utility::Parsables::Entity::Entity(void)" (??0Entity@Parsables@Utility@@QAE@XZ) 1Entity.obj : error LNK2019: unresolved external symbol "public: virtual __thiscall Utility::Parsables::Base::~Base(void)" (??1Base@Parsables@Utility@@UAE@XZ) referenced in function "public: virtual __thiscall Utility::Parsables::Entity::~Entity(void)" (??1Entity@Parsables@Utility@@UAE@XZ) 1D:\Programming\Projects\Caffeine\Debug\Caffeine.exe : fatal error LNK1120: 2 unresolved externals I really can't figure out what's going on.. can anyone see what I'm doing wrong? I'm using Visual C++ Express 2008. Here are the files.. "include/Utility/Parsables/Base.hpp" #ifndef CAFFEINE_UTILITY_PARSABLES_BASE_HPP #define CAFFEINE_UTILITY_PARSABLES_BASE_HPP namespace Utility { namespace Parsables { class Base { public: Base( void ); virtual ~Base( void ); }; } } #endif //CAFFEINE_UTILITY_PARSABLES_BASE_HPP "src/Utility/Parsables/Base.cpp" #include "Utility/Parsables/Base.hpp" namespace Utility { namespace Parsables { Base::Base( void ) { } Base::~Base( void ) { } } } "include/Utility/Parsables/Entity.hpp" #ifndef CAFFEINE_UTILITY_PARSABLES_ENTITY_HPP #define CAFFEINE_UTILITY_PARSABLES_ENTITY_HPP #include "Utility/Parsables/Base.hpp" namespace Utility { namespace Parsables { class Entity : public Base { public: Entity( void ); virtual ~Entity( void ); }; } } #endif //CAFFEINE_UTILITY_PARSABLES_ENTITY_HPP "src/Utility/Parsables/Entity.cpp" #include "Utility/Parsables/Entity.hpp" namespace Utility { namespace Parsables { Entity::Entity( void ) { } Entity::~Entity( void ) { } } }

  Read the article

• Object created in Interface Builder getting dealloc'ed too soon

  - by Collin Allen

  The Project I'm working on a relatively simple iPhone OS project that's navigation controller based, with a root table view and a detail table view. Tap an item in the main list to see its details in a pushed table view. The Setup I broke out the data source for both views into their own objects so as not to muddy the purpose of a view controller. Having done this, the table views no longer have data sources since those methods are now in separate files, so I created an instance of each data source class in the appropriate XIB files with the Object item (dragged it in, then set its class). Then, to actually connect the tableviews to their data sources, I set the dataSource outlet of each tableview to the yellow data source object in Interface Builder. The table view delegates are still set to their view controllers. The Problem The root table view works just fine, but when you tap a row to push to the detail view, the data source object gets instantiated as expected, then immediately dealloc'ed, causing a crash (numberOfSectionsInTableView: gets called on the freed object). I can't figure out why the data source is getting automatically dealloc-ed when I need it right then and there for the detail view, as indicated by my data source object creation and tableview connection in Interface Builder. What's more perplexing is that the very approach works fine for the root tableview! The Question Is there anything obvious I'm missing that would cause this to happen? Or, is this even the right way to instantiate a data source for a table view controller? It seems like poor object oriented programming to do it from within the view controller, which should only be concerned with the view. I could cram everything in two table view controller classes and it would probably work, but it would not be as modular as I'd like. Thanks!

  Read the article

• java heap allocation

  - by gurupriyan.e

  I tried to increase the heap size like the below C:\Data\Guru\Code\Got\adminservice\adminservice>java -Xms512m -Xmx512m Usage: java [-options] class [args...] (to execute a class) or java [-options] -jar jarfile [args...] (to execute a jar file) where options include: -client to select the "client" VM -server to select the "server" VM -hotspot is a synonym for the "client" VM [deprecated] The default VM is client. -cp <class search path of directories and zip/jar files> -classpath <class search path of directories and zip/jar files> A ; separated list of directories, JAR archives, and ZIP archives to search for class files. -D<name>=<value> set a system property -verbose[:class|gc|jni] enable verbose output -version print product version and exit -version:<value> require the specified version to run -showversion print product version and continue -jre-restrict-search | -jre-no-restrict-search include/exclude user private JREs in the version search -? -help print this help message -X print help on non-standard options -ea[:<packagename>...|:<classname>] -enableassertions[:<packagename>...|:<classname>] enable assertions -da[:<packagename>...|:<classname>] -disableassertions[:<packagename>...|:<classname>] disable assertions -esa | -enablesystemassertions enable system assertions -dsa | -disablesystemassertions disable system assertions -agentlib:<libname>[=<options>] load native agent library <libname>, e.g. -agentlib:hprof see also, -agentlib:jdwp=help and -agentlib:hprof=help -agentpath:<pathname>[=<options>] load native agent library by full pathname -javaagent:<jarpath>[=<options>] load Java programming language agent, see java.lang.instrument It gave the help message as above - Does it mean that it was allocated?

  Read the article

• How can I do batch image processing with ImageJ in Java or clojure?

  - by Robert McIntyre

  I want to use ImageJ to do some processing of several thousand images. Is there a way to take any general imageJ plugin and apply it to hundreds of images automatically? For example, say I want to take my thousand images and apply a polar transformation to each--- A polar transformation plugin for ImageJ can be found here: http://rsbweb.nih.gov/ij/plugins/polar-transformer.html Great! Let's use it. From: [http://albert.rierol.net/imagej_programming_tutorials.html#How%20to%20automate%20an%20ImageJ%20dialog] I find that I can apply a plugin using the following: (defn x-polar [imageP] (let [thread (Thread/currentThread) options ""] (.setName thread "Run$_polar-transform") (Macro/setOptions thread options) (IJ/runPlugIn imageP "Polar_Transformer" ""))) This is good because it suppresses the dialog which would otherwise pop up for every image. But running this always brings up a window containing the transformed image, when what I want is to simply return the transformed image. The stupidest way to do what I want is to just close the window that comes up and return the image which it was displaying. Does what I want but is absolutely retarded: (defn x-polar [imageP] (let [thread (Thread/currentThread) options ""] (.setName thread "Run$_polar-transform") (Macro/setOptions thread options) (IJ/runPlugIn imageP "Polar_Transformer" "") (let [return-image (IJ/getImage)] (.hide return-image) return-image))) I'm obviously missing something about how to use imageJ plugins in a programming context. Does anyone know the right way to do this? Thanks, --Robert McIntyre

  Read the article

• Creating a window manager type overlay for Mac OS X

  - by zorg1379

  I want to make my own window manager for OS X, or at least give it the appearance of a new one. I have many designs written down in a book, and would like to implement them. These include altering, or even completely removing, menu bars, creating entirely new guis for switching applications, etc. I know that OS X does not have a window manager, and that basically the functions that an X11 window manager would perform are done by Carbon, Cocoa, the Dock application, and the window server. I've read that it would take an incredible amount of reverse engineering to write my own api, etc. at the hardware level. I am still not that good at programming though, and don't have that kind of time. That's why I was thinking of maybe running an application on top of OS X that will function like a separate window manager - and do everything that the normal OS GUI / window manager would do. Is this possible? For example: making a custom button that would appear upon a certain key combination, that could be clicked to access a document viewer, change the time, minimize a window, etc. Is there some way to access functionality to basic tasks / actions like this without using the default OS X button controls, and implementing them with my own GUI? I am talking about more than a simple theme change, I want to completely change the user experience. This means that this application would be run in a full screen mode that blocks out default OS X menu bars. I've heard something about using graphics architectures to plug in your own window manager? Would this be an option too? If so, how would I go about doing that? Thank you,

  Read the article

• NAMESPACE_SEPARATOR constant

  - by ts

  Hello, Having namespaces in PHP is great. Having '\' as namespace separator is a little bit ... awkward (but if there is someone who thinks that is cool & sexy, I am adding tag "rant" to this post. ;) . So, here goes the question: Are you using in your code NAMESPACE_SEPARATOR constant? As in code below: <?php if (!\defined('NAMESPACE_SEPARATOR') { \define('NAMESPACE_SEPARATOR', '\\'); } // if Pros: consistent with DIRECTORY_SEPARATOR (which all of us are using ;) no mess with escaping (think of '\Foo\Bar' but '\\' . Foo' . '\\' . 'Bar') more readable (IMHO) which gives us in effect an opportunity to write good, namespace-aware autoloaders can resist another change if something scary happens (as with ol'good '::' from PHP 6 alpha) can hide uniquess of '\' as namespace operator in programming language land from strangers ;) Cons: "The reason for DIRECTORY_SEPARATOR is that the value is platform dependent, the namespace separator isn't." (as stated in http://bugs.php.net/bug.php?id=43046) 19 characters instead of 1 ( \ ) or 4 ('\\') There are places where you can't use this (full qualified class names as default class variables) ie: class A { protected $sDefaultReporterClass = '\My\Namespace\DefaultReporter'; } So, what are you thinking ?

  Read the article

• Where can I find a quick reference for standard Basic?

  - by Steve314

  The reason? Pure nostalgia. Anyway, there was a standard for Basic that was published in the late 80s or early 90s. It was probably ISO/IEC 10279:1991, but I don't have access to that and cannot be sure. Whatever this standard was, some of the syntax made its way into Borlands Turbo Basic and Microsofts Visual Basic. I never learned any significant amount of VB, but Turbo Basic is one of those things I played with in my mis-spent youth. At one time, my main reference was an article published in one of the main programming periodicals - maybe Personal Computer World, maybe Byte. A scan of that article (if anyone can even identify it) would be great, but all I really want is a few pages quick reference of that standard syntax. Must be free (I'm not that nostalgic), but it must describe the standard syntax - the whole point is to sort out what is standard as opposed to VB or whatever. EDIT The more I think about this, the more convinced I am that this standard was available around 1987 or 1988. Maybe it was the earlier non-full version of the standard above, or maybe it was pre-acceptance of the standard.

  Read the article

• use of assertions for type checking in php?

  - by user151841

  I do some checking of arguments in my classes in php using exception-throwing functions. I have functions that do a basic check ( ===, in_array etc ) and throw an exception on false. So I can do assertNumeric($argument, "\$argument is not numeric."); instead of if ( ! is_numeric($argument) ) { throw new Exception("\$argument is not numeric."); } Saves some typing I was reading in the comments of the php manual page on assert() that As noted on Wikipedia - "assertions are primarily a development tool, they are often disabled when a program is released to the public." and "Assertions should be used to document logically impossible situations and discover programming errors— if the 'impossible' occurs, then something fundamental is clearly wrong. This is distinct from error handling: most error conditions are possible, although some may be extremely unlikely to occur in practice. Using assertions as a general-purpose error handling mechanism is usually unwise: assertions do not allow for graceful recovery from errors, and an assertion failure will often halt the program's execution abruptly. Assertions also do not display a user-friendly error message." This means that the advice given by "gk at proliberty dot com" to force assertions to be enabled, even when they have been disabled manually, goes against best practices of only using them as a development tool So, am I 'doing it wrong'? What other/better ways of doing this are there?

  Read the article

• In the iPad SplitView template, where's the code that specifies which views are to be used in the Sp

  - by Dr Dork

  In the iPad Programming Guide, it gives the following code example for specifying the two views (firstVC and secondVC) that will be used in the SplitView... - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { MyFirstViewController* firstVC = [[[MyFirstViewController alloc] initWithNibName:@"FirstNib" bundle:nil] autorelease]; MySecondViewController* secondVC = [[[MySecondViewController alloc] initWithNibName:@"SecondNib" bundle:nil] autorelease]; UISplitViewController* splitVC = [[UISplitViewController alloc] init]; splitVC.viewControllers = [NSArray arrayWithObjects:firstVC, secondVC, nil]; [window addSubview:splitVC.view]; [window makeKeyAndVisible]; return YES; } but when I actually create a new SplitView project in Xcode, I don't see any code that specifies which views should be added to the SplitView. Here's the code from the SplitView template... - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { // Override point for customization after app launch rootViewController.managedObjectContext = self.managedObjectContext; // Add the split view controller's view to the window and display. [window addSubview:splitViewController.view]; [window makeKeyAndVisible]; return YES; } Thanks in advance for all your help! I'm going to continue researching this question right now.

  Read the article

• rs232 communication, general timing question

  - by Sunny Dee

  Hi, I have a piece of hardware which sends out a byte of data representing a voltage signal at a frequency of 100Hz over the serial port. I want to write a program that will read in the data so I can plot it. I know I need to open the serial port and open an inputstream. But this next part is confusing me and I'm having trouble understanding the process conceptually: I create a while loop that reads in the data from the inputstream 1 byte at a time. How do I get the while loop timing so that there is always a byte available to be read whenever it reaches the readbyte line? I'm guessing that I can't just put a sleep function inside the while loop to try and match it to the hardware sample rate. Is it just a matter of continuing reading the inputstream in the while loop, and if it's too fast then it won't do anything (since there's no new data), and if it's too slow then it will accumulate in the inputstream buffer? Like I said, i'm only trying to understand this conceptually so any guidance would be much appreciated! I'm guessing the idea is independent of which programming language I'm using, but if not, assume it is for use in Java. Thanks!

  Read the article

• Problem with .Contains

  - by Rene

  Hello there, I have a little problem which i can't solve. I want to use an SQL-In-Statement in Linq. I've read in this Forum and in other Forums that I have to use the .Contains (with reverse-thinking-notation :-)). As input i have a List of Guids. I first copied them into an array and then did something like that : datatoget = (from p in objectContext.MyDataSet where ArrayToSearch.Contains(p.Subtable.Id.ToString()) select p).ToList(); datatoget is the result in which all records matching the Subtable.Id (which is a Guid) should be stored. Subtable is a Detail-Table from MyData, and the Id is a Guid-Type. I've tried several things (Convert Guid to String, and then using .Contains, etc), but I always get an Exception which says : 'Linq to Entities' doesn't recognize the Method 'Boolean Contains(System.Guid) and is not able to Translate this method into a memory expression. (Something like that, because I'm using the German Version of VS2008) I am using L2E with .NET 3.5 and am programming in C# with VS 2008. I've read several Examples, but it doesn't work. Is it perhaps because of using Guid's instead of strings ? I've also tried to write my own compare-function, but I don't know how to integrate it so that .NET calls my function for comparing.

  Read the article

• Windows Phone - OnNavigatingFrom - problem

  - by Martin Anderson

  I believe this is just a problem for me, due to my lack of programming ability. I am currently exploring transitions between page navigation with Windows Phone apps. I was originally using storyboards, and completed event handlers to have my pages animate on and off screen. These leads to the a problem when you want to navigate to many pages from one page, using the same transition. So I have started looking at OnNavigatedTo, and OnNavigatingFrom events and while it is working nicely for OnNavigatedTo, the later just wont work. It seems the Microsoft.Phone.Navigation assembly does not contain OnNavigatingFrom, and referencing System.Windows.Navigation, compiles ok, but I cant get pages to animate off upon navigation. I have a button on my Page2, which I want to go back to my MainPage (after I over-rided the back key with a message box for testing). I have transitions made on the page, and I have this as the event handler code... private void btnP2_BackToP1Clicked(object sender, System.Windows.RoutedEventArgs e) { NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative)); } With this code for the OnNavigatedTo and OnNavigatingFrom events... protected override void OnNavigatedTo(PhoneNavigationEventArgs e) { PageTransition_In.Begin(); } // // protected override void OnNavigatingFrom(NavigatingCancelEventArgs e) { PageTransition_Out.Begin(); base.OnNavigatingFrom(e); } I have the feeling that OnNavigatingFrom may not(yet) be supported for Windows Phone Apps. OnNavigatedFrom is part of Microsoft.Phone.Navigation, but it only performs actions once the page is no longer active, which is too late to perform any animation effects.

  Read the article

• Python Locking Implementation (with threading module)

  - by Matty

  This is probably a rudimentary question, but I'm new to threaded programming in Python and am not entirely sure what the correct practice is. Should I be creating a single lock object (either globally or being passed around) and using that everywhere that I need to do locking? Or, should I be creating multiple lock instances in each of the classes where I will be employing them. Take these 2 rudimentary code samples, which direction is best to go? The main difference being that a single lock instance is used in both class A and B in the second, while multiple instances are used in the first. Sample 1 class A(): def __init__(self, theList): self.theList = theList self.lock = threading.Lock() def poll(self): while True: # do some stuff that eventually needs to work with theList self.lock.acquire() try: self.theList.append(something) finally: self.lock.release() class B(threading.Thread): def __init__(self,theList): self.theList = theList self.lock = threading.Lock() self.start() def run(self): while True: # do some stuff that eventually needs to work with theList self.lock.acquire() try: self.theList.remove(something) finally: self.lock.release() if __name__ == "__main__": aList = [] for x in range(10): B(aList) A(aList).poll() Sample 2 class A(): def __init__(self, theList,lock): self.theList = theList self.lock = lock def poll(self): while True: # do some stuff that eventually needs to work with theList self.lock.acquire() try: self.theList.append(something) finally: self.lock.release() class B(threading.Thread): def __init__(self,theList,lock): self.theList = theList self.lock = lock self.start() def run(self): while True: # do some stuff that eventually needs to work with theList self.lock.acquire() try: self.theList.remove(something) finally: self.lock.release() if __name__ == "__main__": lock = threading.Lock() aList = [] for x in range(10): B(aList,lock) A(aList,lock).poll()

  Read the article

• Template with constant expression: error C2975 with VC++2008

  - by Arman

  Hello, I am trying to use elements of meta programming, but hit the wall with the first trial. I would like to have a comparator structure which can be used as following: intersect_by<ID>(L1.data, L2.data, "By ID: "); intersect_by<IDf>(L1.data, L2.data, "By IDf: "); Where: struct ID{};// Tag used for original IDs struct IDf{};// Tag used for the file position //following Boost.MultiIndex examples template<typename Tag,typename MultiIndexContainer> void intersect_by( const MultiIndexContainer& L1,const MultiIndexContainer& L2,std::string msg, Tag* =0 /* fixes a MSVC++ 6.0 bug with implicit template function parms / ) { / obtain a reference to the index tagged by Tag */ const typename boost::multi_index::index<MultiIndexContainer,Tag>::type& L1_ID_index= get<Tag>(L1); const typename boost::multi_index::index<MultiIndexContainer,Tag>::type& L2_ID_index= get<Tag>(L2); std::set_intersection( L1_ID_index.begin(), L1_ID_index.end(), L2_ID_index.begin(), L2_ID_index.end(), std::inserter(s, s.begin()), strComparator() // Here I get the C2975 error ); } template<int N> struct strComparator; template<> struct strComparator<0>{ bool operator () (const particleID& id1, const particleID& id2) const { return id1.ID struct strComparator<1{ bool operator () (const particleID& id1, const particleID& id2) const { return id1.IDf }; What I am missing? kind regards Arman.

  Read the article

• Windows console

  - by b-gen-jack-o-neill

  Hello. Well, I have a simple question, at least I hope its simple. I was interested in win32 console for a while. Our teacher told us, that windows console is just for DOS and real mode emulation purposes. Well, I know it is not true, becouse DOS applications are runned by emulator which only uses console to display output. Another thing I learned is that console is built into Windows since NT. Well. But what I could not find is, how actually are console programs written to use console. I use Visual C++ for programming (well, for learning). So, the only thing I need to do for using console is select console project. I first thought that windows decides wheather it run app in console or tries to run app in window mode. So I created win32 program and tried printf(). Well, I could not compile it. I know that by definition printf() prints text or variables to stdout. I also found that stdout is the console interface for output. But, I could not find what actually stdout is. So, basicly what I want to ask is, where is the difference between console app and win32 app. I thought that windows starts console when it gets command from "console-family" functions. But obvisously it does not, so there must be some code that actually commands windows to create console interface. And the second question is, when the console is created, how does windows recognize which console terminal is used for what app? I mean, what actually is stdout? Is it a area in memory , or some windows routine that is called? Thanks.

  Read the article

• ASP.NET MVC 2: How to write this Linq SQL as a Dynamic Query (using strings)?

  - by Dr. Zim

  Skip to the "specific question" as needed. Some background: The scenario: I have a set of products with a "drill down" filter (Query Object) populated with DDLs. Each progressive DDL selection will further limit the product list as well as what options are left for the DDLs. For example, selecting a hammer out of tools limits the Product Sizes to only show hammer sizes. Current setup: I created a query object, sent it to a repository, and fed each option to a SQL "table valued function" where null values represent "get all products". I consider this a good effort, but far from DDD acceptable. I want to avoid any "programming" in SQL, hopefully doing everything with a repository. Comments on this topic would be appreciated. Specific question: How would I rewrite this query as a Dynamic Query? A link to something like 101 Linq Examples would be fantastic, but with a Dynamic Query scope. I really want to pass to this method the field in quotes "" for which I want a list of options and how many products have that option. (from p in db.Products group p by p.ProductSize into g select new Category { PropertyType = g.Key, Count = g.Count() }).Distinct(); Each DDL option will have "The selection (21)" where the (21) is the quantity of products that have that attribute. Upon selecting an option, all other remaining DDLs will update with the remaining options and counts.

  Read the article

• Adding libraries to a project in xcode - symbols not found

  - by kudorgyozo

  I am trying to make an iphone app in xcode that uses pjsip. The problem is I don't know how to link the libraries. I have the ARM version of the libraries in this folder in mac os x. /Users/kudorgyozo/pjsip_iphone In Xcode: I have specified the library and header search paths like this: for includes: /Users/kudorgyozo/pjsip_iphone/pjlib/include /Users/kudorgyozo/pjsip_iphone/pjlib-util/include /Users/kudorgyozo/pjsip_iphone/pjmedia/include /Users/kudorgyozo/pjsip_iphone/pjnath/include /Users/kudorgyozo/pjsip_iphone/pjsip/include for libraries: /Users/kudorgyozo/pjsip_iphone/pjlib/lib /Users/kudorgyozo/pjsip_iphone/pjlib-util/lib /Users/kudorgyozo/pjsip_iphone/pjmedia/lib /Users/kudorgyozo/pjsip_iphone/pjnath/lib /Users/kudorgyozo/pjsip_iphone/pjsip/lib and then using the "Other linker flags" : -lpj-arm-apple-darwin9 -lpjlib-util-arm-apple-darwin9 -lpjmedia-arm-apple-darwin9 -lpjmedia-audiodev-arm-apple-darwin9 -lpjmedia-codec-arm-apple-darwin9 -lpjsdp-arm-apple-darwin9 -lpjnath-arm-apple-darwin9 -lpjsip-arm-apple-darwin9 -lpjsip-simple-arm-apple-darwin9 -lpjsip-ua-arm-apple-darwin9 -lpjsua-arm-apple-darwin9 Is this OK like this? Because it gives me symbol(s) not found errors. I think no symbol is found from the "included" libraries. I don't know what is wrong i'm just beginning to understand how building an app works under linux based systems i've only done programming in C# before.

  Read the article

• Types issue in F#

  - by Andry

  Hello! In my ongoing adventure deep diving into f# I am understanding a lot of this powerful language but there are things that I still do not understand so clearly. One of the most important issues I need to master is types. Well the book I am reading is very straight forward and introduces entities and main functionalities with a direct approach. The first thing I could get start with is types. It introduces the main types as list, option, tuples, and so on... It is clearly underlined that all these types are IMMUTABLE for many reasons regarding functional programming and data consistance in functional programing. Well, no problems until now... But now I am getting started with Concrete Types... Well... I have problems in managing with types like list, option, tuples, types created through new operator and concrete types created using type keyword (for abbreviations, concrete types...). So my question is: how can I efficently catalogue/distinguish all types of data in f#???? I can create a perfect separation among types in C#, VB.NET... FOr example in VB.NET there are value and reference types while in C# there are only references and also int, double are treated as objects (they are objects while in VB.NET a value type is not a object and there is a split in types for this reason). Well in F# I cannot create such differences among types in the language. Can you help me? I hope I was clear.

  Read the article

• Internet Explorer cannot 'fully' load ActiveX Control

  - by K Browne

  Context I am migrating an installer for an ActiveX control from Per-Machine to Per-User. I did this by programming the installer write to HKCU\Software\Classes instead of HKLM\Software\Classes. Problem On my machine (Windows 7 with UAC Enabled), the ActiveX control successfully loads. On the other windows 7 test machines (one with UAC enabled, one with UAC disabled), the control 'partially' loads. What is Partially? When a user visits a page with the ActiveX control, Internet Explorer displays a warning message in a yellow bar on the top of the window. If you click the 'Run add-on' button in the bar, the control becomes visible and begins to run, but Javascript code that tries to access properties of the control return the error: Library not registered. Differences between machines On the dev machine reads from HKCR\CLSID\<GUID> succeed while on the test machines these reads fail. Reads from HKCU succeed on both dev and test machines. Reads from HKLM fail on both test and dev machines. (I collected reads using Sysinternals Process Monitor) Strangely, the keys that Internet Explorer fails to read are clearly visible if I use regedit to view HKCR\CLSID\<GUID> on the test machines. Question What can I do to get the per-user control to load on the test machines? What could cause this difference between the dev machine and the test machines? Why can I see the key in HKCR with RegEdit but Internet Explorer cannot see the key? Any help is appreciated. Thank you.

  Read the article

< Previous Page | 443 444 445 446 447 448 449 450 451 452 453 454  | Next Page >