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  • php OOP function declarations

    - by kris
    I'm a big fan of OOP in php, but i feel like defining class methods gets disorganized so fast. I have a pretty good background in OOP in C++, and i am pretty comfortable with how it is handled there, and am curious if there are ways to do it similarly in php. To be more specific, here is what i mean. I like how in C++ you can define a class header (myclass.h) and then define the actual details of the functions in the implementation file (myclass.cc). Ive found that this can easily be replicated using interfaces in php, but i havent found a good solution for the following: I like to organize my code in C++ in different files based on how they are accessed, so for example, public methods that can be called outside of the class would be in 1 place, and private methods would be organized somewhere else - this is personal preference. Ive tried to define class methods in php like: private function MyPHPClass::myFunction(){ } when the definition isnt directly inside the class block( { } ), but i havent had any success doing this. Ive been through all of the pages on php.net, but couldnt find anything like this. Im assuming that there is no support for something like this, but thought i would ask anyway. thanks

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  • Concise C# code for gathering several properties with a non-null value into a collection?

    - by stakx
    A fairly basic problem for a change. Given a class such as this: public class X { public T A; public T B; public T C; ... // (other fields, properties, and methods are not of interest here) } I am looking for a concise way to code a method that will return all A, B, C, ... that are not null in an enumerable collection. (Assume that declaring these fields as an array is not an option.) public IEnumerable<T> GetAllNonNullAs(this X x) { // ? } The obvious implementation of this method would be: public IEnumerable<T> GetAllNonNullAs(this X x) { var resultSet = new List<T>(); if (x.A != null) resultSet.Add(x.A); if (x.B != null) resultSet.Add(x.B); if (x.C != null) resultSet.Add(x.C); ... return resultSet; } What's bothering me here in particular is that the code looks verbose and repetitive, and that I don't know the initial List capacity in advance. It's my hope that there is a more clever way, probably something involving the ?? operator? Any ideas?

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  • Sticky/static variable references in for loops

    - by pthulin
    In this example I create three buttons 'one' 'two' 'three'. When clicked I want them to alert their number: <html> <head> <script type="application/javascript" src="jquery.js"></script> <script type="application/javascript"> $(document).ready(function() { var numbers = ['one', 'two', 'three']; for (i in numbers) { var nr = numbers[i]; var li = $('<li>' + nr + '</li>'); li.click(function() { var newVariable = String(nr); alert(i); // 2 alert(nr); // three alert(newVariable); // three alert(li.html()); // three }); $('ul').append(li); } }); </script> </head> <body> <ul> </ul> </body> </html> The problem is, when any of these are clicked, the last value of the loop's variables is used, i.e. alert box always says 'three'. In JavaScript, variables inside for-loops seem to be 'static' in the C language sense. Is there some way to create separate variables for each click function, i.e. not using the same reference? Thanks!

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  • C++ operator lookup rules / Koenig lookup

    - by John Bartholomew
    While writing a test suite, I needed to provide an implementation of operator<<(std::ostream&... for Boost unit test to use. This worked: namespace theseus { namespace core { std::ostream& operator<<(std::ostream& ss, const PixelRGB& p) { return (ss << "PixelRGB(" << (int)p.r << "," << (int)p.g << "," << (int)p.b << ")"); } }} This didn't: std::ostream& operator<<(std::ostream& ss, const theseus::core::PixelRGB& p) { return (ss << "PixelRGB(" << (int)p.r << "," << (int)p.g << "," << (int)p.b << ")"); } Apparently, the second wasn't included in the candidate matches when g++ tried to resolve the use of the operator. Why (what rule causes this)? The code calling operator<< is deep within the Boost unit test framework, but here's the test code: BOOST_AUTO_TEST_SUITE(core_image) BOOST_AUTO_TEST_CASE(test_output) { using namespace theseus::core; BOOST_TEST_MESSAGE(PixelRGB(5,5,5)); // only compiles with operator<< definition inside theseus::core std::cout << PixelRGB(5,5,5) << "\n"; // works with either definition BOOST_CHECK(true); // prevent no-assertion error } BOOST_AUTO_TEST_SUITE_END() For reference, I'm using g++ 4.4 (though for the moment I'm assuming this behaviour is standards-conformant).

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  • Getting around IBActions limited scope

    - by Septih
    Hello, I have an NSCollectionView and the view is an NSBox with a label and an NSButton. I want a double click or a click of the NSButton to tell the controller to perform an action with the represented object of the NSCollectionViewItem. The Item View is has been subclassed, the code is as follows: #import <Cocoa/Cocoa.h> #import "WizardItem.h" @interface WizardItemView : NSBox { id delegate; IBOutlet NSCollectionViewItem * viewItem; WizardItem * wizardItem; } @property(readwrite,retain) WizardItem * wizardItem; @property(readwrite,retain) id delegate; -(IBAction)start:(id)sender; @end #import "WizardItemView.h" @implementation WizardItemView @synthesize wizardItem, delegate; -(void)awakeFromNib { [self bind:@"wizardItem" toObject:viewItem withKeyPath:@"representedObject" options:nil]; } -(void)mouseDown:(NSEvent *)event { [super mouseDown:event]; if([event clickCount] > 1) { [delegate performAction:[wizardItem action]]; } } -(IBAction)start:(id)sender { [delegate performAction:[wizardItem action]]; } @end The problem I've run into is that as an IBAction, the only things in the scope of -start are the things that have been bound in IB, so delegate and viewItem. This means that I cannot get at the represented object to send it to the delegate. Is there a way around this limited scope or a better way or getting hold of the represented object? Thanks.

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  • Attempting to Convert Byte[] into Image... but is there platform issues involved

    - by user305535
    Greetings, Current, I'm attempting to develop an application that takes a Byte Array that is streamed to us from a Linux C language program across a TCPClient (stream) and reassemble it back into an image/jpg. The "sending" application was developed by a off-site developer who claims that the image reassembles back into an image without any problems or errors in his test environment (all Linux)... However, we are not so fortunate. I (believe) we successfully get all of the data sent, storing it as a string (lets us append the stream until it is complete) and then we convert it back into a Byte[]. This appears to be working fine... But, when we take the byte[] we get from the streaming (and our string assembly) and try to convert it into an image using the System.Drawing.Image.FromStream() we get errors.... Anyone have any idea what we're doing wrong? Or, does anyone know if this is a cross-platform issue? We're developing our app for Windows XP and C# .net, but the off-site developer did his work in c and Linux... perhaps there's some difference as to how each Operating System Coverts Images into Byte Arrays? Anyway, here's the code for converting our received ByteArray (from the TCPClient Stream) into an image. This code works when we send an image from a test machine we built that RUNS on XP, but not from the Linux box... System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding(); byte[] imageBytes = encoding.GetBytes(data); MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length); // Convert byte[] to Image ms.Write(imageBytes, 0, imageBytes.Length); System.Drawing.Image image = System.Drawing.Image.FromStream(ms, false); <-- DIES here, throws a {System.ArgumentException: Parameter is not valid.} error Any advice, suggestions, theories, or HELP would be GREATLY appreciated! Please let me know??? Best wishes all! Thanks in advance! Greg

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  • Is there a standard pattern for scanning a job table executing some actions?

    - by Howiecamp
    (I realize that my title is poor. If after reading the question you have an improvement in mind, please either edit it or tell me and I'll change it.) I have the relatively common scenario of a job table which has 1 row for some thing that needs to be done. For example, it could be a list of emails to be sent. The table looks something like this: ID Completed TimeCompleted anything else... ---- --------- ------------- ---------------- 1 No blabla 2 No blabla 3 Yes 01:04:22 ... I'm looking either for a standard practice/pattern (or code - C#/SQL Server preferred) for periodically "scanning" (I use the term "scanning" very loosely) this table, finding the not-completed items, doing the action and then marking them completed once done successfully. In addition to the basic process for accomplishing the above, I'm considering the following requirements: I'd like some means of "scaling linearly", e.g. running multiple "worker processes" simultaneously or threading or whatever. (Just a specific technical thought - I'm assuming that as a result of this requirement, I need some method of marking an item as "in progress" to avoid attempting the action multiple times.) Each item in the table should only be executed once. Some other thoughts: I'm not particularly concerned with the implementation being done in the database (e.g. in T-SQL or PL/SQL code) vs. some external program code (e.g. a standalone executable or some action triggered by a web page) which is executed against the database Whether the "doing the action" part is done synchronously or asynchronously is not something I'm considering as part of this question.

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  • Mercurial repository usage with binary files for building setup files

    - by Ryan
    I have an existing Mercurial repository for a C++ application in a small corporate environment. I asked a co-worker to add the setup script to the repository and he added all of the dependency binaries, PDFs, and executable to the repository under an Install directory. I dislike having the binaries and dependencies in the same repository, but I'd like recommendations on best practices. Here are the options I am considering: Create a separate repository for the Installer and related files Create a subrepository for the Installer and related files Use a (yet to be identified) build dependency manager I am concerned with using a subrepository with Mercurial based on what I've read so far and the (apparently) incomplete implementation. I would like to get a project dependency system, e.g. Ivy, but I don't know all of the options and haven't had time yet to try out any options. I thought I'd use TortoiseHg as a basis, and it does not have the TortoiseHg binaries in the repository although it does have some binaries such as kdiff3.exe. Instead it uses setup.py to clone multiple repositories and build the apps. This seems reasonable for OSS, but not so much for corporate environments. Recommendations?

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  • ASP.NET page with base class with dynamic master page not firing events

    - by Kangkan
    Hi guys! I am feeling that I have terribly wrong somewhere. I was working on a small asp.net app. I have some dynamic themes in the \theme folder and have implemented a page base class to load the master page on the fly. The master is having the ContentPlaceHolder like: <asp:ContentPlaceHolder ID="cphBody" runat="server" /> Now I am adding pages that are derived from my base class and added the form elements. I know, Visual Studio has problem showing the page in the design mode. I have a dropdown box and wish to add the event of onselectedindexchange. But it is not working. the page is like this: <%@ Page Language="C#" AutoEventWireup="true" Inherits="trigon.web.Pages.MIS.JobStatus" Title="Job Status" AspCompat="true" CodeBehind="JobStatus.aspx.cs" %> <asp:Content ID="Content1" ContentPlaceHolderID="cphBody" runat="Server"> <div id="divError" runat="server" /> <asp:DropDownList runat="server" id="jobType" onselectedindexchange="On_jobTypeSelection_Change"></asp:DropDownList> </asp:Content> I have also tried adding the event on the code behind like: protected void Page_Load(object sender, EventArgs e) { jobType.SelectedIndexChanged += new System.EventHandler(this.On_jobTypeSelection_Change); if (!IsPostBack) { JobStatus_DA da = new JobStatus_DA(); jobType.DataSource = da.getJobTypes(); jobType.DataBind(); } } protected void On_jobTypeSelection_Change(Object sender, EventArgs e) { //do something here } Can anybody help? Regards,

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  • javascript, php, cookies

    - by kennedy
    When i declare mac = 123, my internet explorer and firefox will keep refresh non-stop. And if i declare mac = getMacAddress it returns a value 1... I'm able to do a document.write(getMacAddress()) and it would able to display the mac address nicely. 1) Why my explorer will keep refreshing non-stop when i code it manually with "123" 2) why is the document.write able to display out, and when i store it to the cookie, somehow it didnt mange to capture into the cookie and it return a value of "1". Anyone help? create_users.php <script language="JavaScript"> function getMacAddress(){ document.macaddressapplet.setSep( "-" ); return (document.macaddressapplet.getMacAddress()); } function setCookie(c_name,value) { document.cookie = c_name + "=" +escape(value); } //error checking //var mac = getMacAddress(); var mac = "123"; setCookie('cookie_name',mac); window.location = "checkAvailability.php"; </script> checkAvailability.php $javascript_cookie_value = isset($_COOKIE["cookie_name"]) ? $_COOKIE["cookie_name"] : 1; mysql_query("INSERT INTO test (mac) VALUES ('$javascript_cookie_value')");

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  • What should I do if i have a factory method which requires different parameters for different implem

    - by Sam Holder
    I have an interface, IMessage and a class which have several methods for creating different types of message like so: class MessageService { IMessage TypeAMessage(param 1, param 2) IMessage TypeBMessage(param 1, param 2, param 3, param 4) IMessage TypeCMessage(param 1, param 2, param 3) IMessage TypeDMessage(param 1) } I don't want this class to do all the work for creating these messages so it simply delegates to a MessageCreatorFactory which produces an IMessageCreator depending on the type given (an enumeration based on the type of the message TypeA, TypeB, TypeC etc) interface IMessageCreator { IMessage Create(MessageParams params); } So I have 4 implementations of IMessageCreator: TypeAMessageCreator, TypeBMessageCreator, TypeCMessageCreator, TypeDMessageCreator I ok with this except for the fact that because each type requires different parameters I have had to create a MessageParams object which contains 4 properties for the 4 different params, but only some of them are used in each IMessageCreator. Is there an alternative to this? One other thought I had was to have a param array as the parameter in the Create emthod, but this seems even worse as you don't have any idea what the params are. Or to create several overloads of Create in the interface and have some of them throw an exception if they are not suitable for that particular implementation (ie you called a method which needs more params, so you should have called one of the other overloads.) Does this seem ok? Is there a better solution?

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  • Preventing HTML character entities in locale files from getting munged by Rails3 xss protection

    - by Chris S
    We're building an app, our first using Rails 3, and we're having to build I18n in from the outset. Being perfectionists, we want real typography to be used in our views: dashes, curled quotes, ellipses et al. This means in our locales/xx.yml files we have two choices: Use real UTF-8 characters inline. Should work, but hard to type, and scares me due to the amount of software which still does naughty things to unicode. Use HTML character entities (&#8217; &#8212; etc). Easier to type, and probably more compatible with misbehaving software. I'd rather take the second option, however the auto-escaping in Rails 3 makes this problematic, as the ampersands in the YAML get auto-converted into character entities themselves, resulting in 'visible' &8217;s in the browser. Obviously this can be worked around by using raw on strings, i.e.: raw t('views.signup.organisation_details') But we're not happy going down the route of globally raw-ing every time we t something as it leaves us open to making an error and producing an XSS hole. We could selectively raw strings which we know contain character entities, but this would be hard to scale, and just feels wrong - besides, a string which contains an entity in one language may not in another. Any suggestions on a clever rails-y way to fix this? Or are we doomed to crap typography, xss holes, hours of wasted effort or all thre?

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  • switching C compiler causes: Error Initializer cannot be specified for a flexible array member

    - by user1054210
    I am trying to convert our code from one IDE to be used in a different one. The current one uses gcc which allows for this structure to be initialized from a variable array. The new tool does not use gcc gives me an error "Initializer cannot be specified for a flexible array member". So can someone help me understand how to set this up? Should I set up a blank array of variable size and then somewhere assign the #define array as seen below? Here would be an example of the code…(this is current implementation current IDE) In one header file that is Build switchable so we can build this on different hardware platforms we have the following #define #define GPIOS \ /* BANK, PIN, SPD, MODE,… */ GPIOINIT( A, 0, 2, AIN, …) \ GPIOINIT( A, 1, 2, AIN, …) \ GPIOINTINIT(A, 2, 2, AIN, …) \ . . . Then in a different header file that is used in all builds we have PLATFORM_CONFIG_T g_platformConfig = { .name = {PLATFORM_NAME}, (bunch of other stuff), .allGpios = { GPIOS /* here I get the error */ }, }; So I am thinking I can make the error line a variable array and assign to it later in some other way? The problem is the actual array "GPIO" is of different types and pin orders on different designs are different.

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  • 'C++ object destroyed' in QComboBox descendant editor in delegate

    - by Max
    Hi, all! I have modified combobox to hold colors, using QtColorCombo (http://qt.nokia.com/products/appdev/add-on-products/catalog/4/Widgets/qtcolorcombobox) as howto for the 'more...' button implementation details. It works fine in C++ and in PyQt on linux, but I get 'underlying C++ object was destroyed' when use this control in PyQt on Windows. It seels like the error happens when: ... # in constructor: self.activated.connect(self._emitActivatedColor) ... def _emitActivatedColor(self, index): if self._colorDialogEnabled and index == self.colorCount(): print '!!!!!!!!! QtGui.QColorDialog.getColor()' c = QtGui.QColorDialog.getColor() # <----- :( delegate fires 'closeEditor' print '!!!!!!!!! ' + c.name() if c.isValid(): self._numUserColors += 1 #at the next line currentColor() tries to access C++ layer and fails self.addColor(c, self.currentColor().name()) self.setCurrentIndex(index) ... Maybe console output will help. I've overridden event() in editor and got: ... MouseButtonRelease FocusOut Leave Paint Enter Leave FocusIn !!!!!!!!! QtGui.QColorDialog.getColor() WindowBlocked Paint WindowDeactivate !!!!!!!!! 'CloseEditor' fires! Hide HideToParent FocusOut DeferredDelete !!!!!!!!! #6e6eff ... Can someone explain, why there is such a different behaviour in the different environments, and maybe give a workaround to fix this. Here is minimal example: http://docs.google.com/Doc?docid=0Aa0otNVdbWrrZDdxYnF3NV80Y20yam1nZHM&hl=en

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  • Drupal module permissions

    - by Trevor Newhook
    When I run the code with an admin user, the module returns what it should. However, when I run it with a normal user, I get a 403 error. The module returns data from an AJAX call. I've already tried adding a 'access callback' = 'user_access'); line to the exoticlang_chat_logger_menu() function. I'd appreciate any pointers you might have. Thanks for the help The AJAX call: jQuery.ajax({ type: 'POST', url: '/chatlog', success: exoticlangAjaxCompleted, data:'messageLog=' + privateMessageLogJson, dataType: 'json' }); The module code: function exoticlang_chat_logger_init(){ drupal_add_js('misc/jquery.form.js'); drupal_add_library('system', 'drupal.ajax'); } function exoticlang_chat_logger_permission() { return array( 'Save chat data' => array( 'title' => t('Save ExoticLang Chat Data'), 'description' => t('Send private message on chat close') ), ); } /** * Implementation of hook_menu(). */ function exoticlang_chat_logger_menu() { $items = array(); $items['chatlog'] = array( 'type' => MENU_CALLBACK, 'page callback' => 'exoticlang_chat_log_ajax', 'access arguments' => 'Save chat data'); //'access callback' => 'user_access'); return $items; } function exoticlang_chat_logger_ajax(){ $messageLog=stripslashes($_POST['messageLog']); $chatLog= 'Drupal has processed this. Message log is: '.$messageLog; $chatLog=str_replace('":"{[{','":[{',$chatLog); $chatLog=str_replace(',,',',',$chatLog); $chatLog=str_replace('"}"','"}',$chatLog); $chatLog=str_replace('"}]}"','"}]',$chatLog); echo json_encode(array('messageLog' => $chatLog)); // echo $chatLog; echo print_r(privatemsg_new_thread(array(user_load(1)), 'The subject', 'The body text')); drupal_exit(); }

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  • Change title of UINavigationBar

    - by Lemmy
    I've created a view-based application. I've placed a Navigation Bar on the view and two buttons. I'd like to change the title of the nav bar after pressing the buttons. In IB I've connected the buttons with the corresponding actions. Debugging shows that the actions are getting called but the title of the nav bar is not changed. Kindly help! // // NavBarViewController.h #import <UIKit/UIKit.h> @interface NavBarViewController : UIViewController { } -(IBAction) clickedOne: (id)sender; -(IBAction) clickedTwo: (id)sender; @end // // NavBarViewController.m #import "NavBarViewController.h" @implementation NavBarViewController -(IBAction) clickedOne: (id)sender { self.navigationItem.title = @"1"; } -(IBAction) clickedTwo: (id)sender { self.navigationItem.title = @"2"; } - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Release any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Release any retained subviews of the main view. // e.g. self.myOutlet = nil; } - (void)dealloc { [super dealloc]; } @end

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  • How do I send the mutable string to the NSTextField properly?

    - by Merle
    So I have all this code that I have debugged and it seems to be fine. I made a mutable string and for some reason I can not get it to be displayed on my label. the debugger says "2010-04-22 22:50:26.126 Fibonacci[24836:10b] * -[NSTextField setString:]: unrecognized selector sent to instance 0x130150" What is wrong with this? When I just send the string to NSLog, it comes out fine. here's all my code, any help would be appreciated. "elementNum" is a comboBox and "display" is a Label. Thanks #import "Controller.h" @implementation Controller - (IBAction)computeNumber:(id)sender { int x = 1; int y = 1; NSMutableString *numbers = [[NSMutableString alloc] init]; [numbers setString:@"1, 1,"]; int num = [[elementNum objectValueOfSelectedItem]intValue]; int count = 1; while (count<=num) { int z = y; y+=x; x=z; [numbers appendString:[NSString stringWithFormat:@" %d,", y]]; count++; } [display setString:numbers]; NSLog(numbers); } @end `

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  • Safe and polymorphic toEnum

    - by jetxee
    I'd like to write a safe version of toEnum: safeToEnum :: (Enum t, Bounded t) => Int -> Maybe t A naive implementation: safeToEnum :: (Enum t, Bounded t) => Int -> Maybe t safeToEnum i = if (i >= fromEnum (minBound :: t)) && (i <= fromEnum (maxBound :: t)) then Just . toEnum $ i else Nothing main = do print $ (safeToEnum 1 :: Maybe Bool) print $ (safeToEnum 2 :: Maybe Bool) And it doesn't work: safeToEnum.hs:3:21: Could not deduce (Bounded t1) from the context () arising from a use of `minBound' at safeToEnum.hs:3:21-28 Possible fix: add (Bounded t1) to the context of an expression type signature In the first argument of `fromEnum', namely `(minBound :: t)' In the second argument of `(>=)', namely `fromEnum (minBound :: t)' In the first argument of `(&&)', namely `(i >= fromEnum (minBound :: t))' safeToEnum.hs:3:56: Could not deduce (Bounded t1) from the context () arising from a use of `maxBound' at safeToEnum.hs:3:56-63 Possible fix: add (Bounded t1) to the context of an expression type signature In the first argument of `fromEnum', namely `(maxBound :: t)' In the second argument of `(<=)', namely `fromEnum (maxBound :: t)' In the second argument of `(&&)', namely `(i <= fromEnum (maxBound :: t))' As well as I understand the message, the compiler does not recognize that minBound and maxBound should produce exactly the same type as in the result type of safeToEnum inspite of the explicit type declaration (:: t). Any idea how to fix it?

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  • creating matrix with probabilities

    - by John Chan
    Hi all, I want to generate a matrix of NxN to test some code that I have where each row contains floats as the elements and has to add up to 1 (i.e. a row with a set of probabilities). Where it gets tricky is that I want to make sure that randomly some of the elements should be 0 (in fact most of the elements should be 0 except for some random ones to be the probabilities). I need the probabilities to be 1/m where m is the number of elements that are not 0 within a single row. I tried to think of ways to output this, but essentially I would need this stored in a C++ array. So even if I output to a file I would still have the issue of not having it in array as I need it. At the end of it all I need that array because I want to generate a Market Matrix file. I found an implementation in C++ to take an array and convert it to the market matrix file, so this is what I am basing my findings on. My input for the rest of the code takes in this market matrix file so I need that to be the primary form of output. The language does not matter, I just want to generate the file at the end (I found a way mmwrite and mmread in python as well) Please help, I am stuck and not really sure how to implement this.

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  • Fastest inline-assembly spinlock

    - by sigvardsen
    I'm writing a multithreaded application in c++, where performance is critical. I need to use a lot of locking while copying small structures between threads, for this I have chosen to use spinlocks. I have done some research and speed testing on this and I found that most implementations are roughly equally fast: Microsofts CRITICAL_SECTION, with SpinCount set to 1000, scores about 140 time units Implementing this algorithm with Microsofts InterlockedCompareExchange scores about 95 time units Ive also tried to use some inline assembly with __asm {} using something like this code and it scores about 70 time units, but I am not sure that a proper memory barrier has been created. Edit: The times given here are the time it takes for 2 threads to lock and unlock the spinlock 1,000,000 times. I know this isn't a lot of difference but as a spinlock is a heavily used object, one would think that programmers would have agreed on the fastest possible way to make a spinlock. Googling it leads to many different approaches however. I would think this aforementioned method would be the fastest if implemented using inline assembly and using the instruction CMPXCHG8B instead of comparing 32bit registers. Furthermore memory barriers must be taken into account, this could be done by LOCK CMPXHG8B (I think?), which guarantees "exclusive rights" to the shared memory between cores. At last [some suggests] that for busy waits should be accompanied by NOP:REP that would enable Hyper-threading processors to switch to another thread, but I am not sure whether this is true or not? From my performance-test of different spinlocks, it is seen that there is not much difference, but for purely academic purpose I would like to know which one is fastest. However as I have extremely limited experience in the assembly-language and with memory barriers, I would be happy if someone could write the assembly code for the last example I provided with LOCK CMPXCHG8B and proper memory barriers in the following template: __asm { spin_lock: ;locking code. spin_unlock: ;unlocking code. }

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  • Unity in C# for Platform Specific Implementations

    - by DxCK
    My program has heavy interaction with the operating system through Win32API functions. now i want to migrate my program to run under Mono under Linux (No wine), and this requires different implementations to the interaction with the operating system. I started designing a code that can have different implementation for difference platform and is extensible for new future platforms. public interface ISomeInterface { void SomePlatformSpecificOperation(); } [PlatformSpecific(PlatformID.Unix)] public class SomeImplementation : ISomeInterface { #region ISomeInterface Members public void SomePlatformSpecificOperation() { Console.WriteLine("From SomeImplementation"); } #endregion } public class PlatformSpecificAttribute : Attribute { private PlatformID _platform; public PlatformSpecificAttribute(PlatformID platform) { _platform = platform; } public PlatformID Platform { get { return _platform; } } } public static class PlatformSpecificUtils { public static IEnumerable<Type> GetImplementationTypes<T>() { foreach (Assembly assembly in AppDomain.CurrentDomain.GetAssemblies()) { foreach (Type type in assembly.GetTypes()) { if (typeof(T).IsAssignableFrom(type) && type != typeof(T) && IsPlatformMatch(type)) { yield return type; } } } } private static bool IsPlatformMatch(Type type) { return GetPlatforms(type).Any(platform => platform == Environment.OSVersion.Platform); } private static IEnumerable<PlatformID> GetPlatforms(Type type) { return type.GetCustomAttributes(typeof(PlatformSpecificAttribute), false) .Select(obj => ((PlatformSpecificAttribute)obj).Platform); } } class Program { static void Main(string[] args) { Type first = PlatformSpecificUtils.GetImplementationTypes<ISomeInterface>().FirstOrDefault(); } } I see two problems with this design: I can't force the implementations of ISomeInterface to have a PlatformSpecificAttribute. Multiple implementations can be marked with the same PlatformID, and i dont know witch to use in the Main. Using the first one is ummm ugly. How to solve those problems? Can you suggest another design?

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  • How to find an embedded platform?

    - by gmagana
    I am new to the locating hardware side of embedded programming and so after being completely overwhelmed with all the choices out there (pc104, custom boards, a zillion option for each board, volume discounts, devel kits, ahhh!!) I am asking here for some direction. Basically, I must find a new motherboard and (most likely) re-implement the program logic. Rewriting this in C/C++/Java/C#/Pascal/BASIC is not a problem for me. so my real problem is finding the hardware. This motherboard will have several other devices attached to it. Here is a summary of what I need to do: Required: 2 RS232 serial ports (one used all the time for primary UI, the second one not continuous) 1 modem (9600+ baud ok) [Modem will be in simultaneous use with only one of the serial port devices, so interrupt sharing with one serial port is OK, but not both] Minimum permanent/long term storage: Whatever O/S requires + 1 MB (executable) + 512 KB (Data files) RAM: Minimal, whatever the O/S requires plus maybe 1MB for executable. Nice to have: USB port(s) Ethernet network port Wireless network Implementation languages (any O/S I will adapt to): First choice Java/C# (Mono ok) Second choice is C/Pascal Third is BASIC Ok, given all this, I am having a lot of trouble finding hardware that will support this that is low in cost. Every manufacturer site I visit has a lot of options, and it's difficult to see if their offering will even satisfy my must-have requirements (for example they sometimes list 3 "serial ports", but it appears that only one of the three is RS232, for example, and don't mention what the other two are). The #1 constraint is cost, #2 is size. Can anyone help me with this? This little task has left me thinking I should have gone for EE and not CS :-). EDIT: A bit of background: This is a system currently in production, but the original programmer passed away, and the current hardware manufacturer cannot find hardware to run the (currently) DOS system, so I need to reimplement this in a modern platform. I can only change the programming and the motherboard hardware.

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  • What is a good automated data import method for SQL Server?

    - by Joel Potter
    I'm in the process of porting some SQL Server 2005 databases to SQL Server 2008. One of these databases has an associated import application (Windows task) which uses SSIS with a DTS package to import a large dataset from an MS Access database nightly. In upgrading to SQL Server 2008, I discovered that I can't run the same console application which has been performing the imports due to the missing manageddts DLL in SQL Server 2008. It's several years old and in need of a rewrite for various reason, plus, I've been fairly unhappy with DTS in general. The original reason DTS was chosen was for speed (5 min import time compared to 30+ for ADO.NET). The format of the data to import is out of my control (the client likes Access). I would also like to be able to run the import from a machine completely separate from the server hosting SQL Server and preferably with minimal SQL features installed. Options I've considered: Creating an Access application to connect to both databases (SQL Server and Access) and perform the import (Ugh!) Revisiting ADO.NET to see if the original implementation was poorly written. Updated SSIS packages. What other technologies should I be considering for this job?

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  • Multiple websites, Single sign-on design

    - by Yannis
    Hi all, I have a question. A client I have been doing some work recently has a range of websites with different login mechanisms. He is looking to slowly migrate to a single sign-on mechanism for his websites (all written in asp.net mvc). I am looking at my options here, so here is a list of requirements: 1) It has to be secure (duh) 2) It needs to support extra user properties over and above the usual name, address stuff (such as money or credits for a user) 3) It has to provide a centralized user management web console for his convenience (I understand that this will be a small project on top of whatever design solution I choose to go for) 4) It has to integrate with the existing websites without re-engineering the whole product (I understand that this depends on the current product implementation). 5) It has to deal with emailing the user when he registers (in order for him to activate his account) 6) It has to deal with activating the user when he clicks the activate me link in the email (I understand that 5 and 6 require some form of email templating system to support different emails per application) I was thinking of creating a library working together with forms authentication that exposes whatever methods are required (e.g. login, logout, activate, etc. and a small restful service to implement activation from email, registration processing etc. Taking into account that loads of things have been left out to make this question brief and to the point, does this sound like a good design? But this looks like a very common problem so arent there any existing projects that I could use? Thanks for reading.

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  • DotNetOpenAuth / WebSecurity Basic Info Exchange

    - by Jammer
    I've gotten a good number of OAuth logins working on my site now. My implementation is based on the WebSecurity classes with amends to the code to suit my needs (I pulled the WebSecurity source into mine). However I'm now facing a new set of problems. In my application I have opted to make the user email address the login identifier of choice. It's naturally unique and suits this use case. However, the OAuth "standards" strikes again. Some providers will return your email address as "username" (Google) some will return the display name (Facebook). As it stands I see to options given my particular scenario: Option 1 Pull even more framework source code into my solution until I can chase down where the OpenIdRelyingParty class is actually interacted with (via the DotNetOpenAuth.AspNet facade) and make addition information requests from the OpenID Providers. Option 2 When a user first logs in using an OpenID provider I can display a kind of "complete registration" form that requests missing info based on the provider selected.* Option 2 is the most immediate and probably the quickest to implement but also includes some code smells through having to do something different based on the provider selected. Option 1 will take longer but will ultimately make things more future proof. I will need to perform richer interactions down the line so this also has an edge in that regard. The more I get into the code it does seem that the WebSecurity class itself is actually very limiting as it hides lots of useful DotNetOpenAuth functionality in the name of making integration easier. Andrew (the author of DNOA) has said that the Attribute Exchange stuff happens in the OpenIdRelyingParty class but I cannot see from the DotNetOpenAuth.AspNet source code where this class is used so I'm unsure of what source would need to be pulled into my code in order to enable the functionality I need. Has anyone completely something similar?

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