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  • How much is too much memory allocation in NDK?

    - by Maximus
    The NDK download page notes that, "Typical good candidates for the NDK are self-contained, CPU-intensive operations that don't allocate much memory, such as signal processing, physics simulation, and so on." I came from a C background and was excited to try to use the NDK to operate most of my OpenGL ES functions and any native functions related to physics, animation of vertices, etc... I'm finding that I'm relying quite a bit on Native code and wondering if I may be making some mistakes. I've had no trouble with testing at this point, but I'm curious if I may run into problems in the future. For example, I have game struct defined (somewhat like is seen in the San-Angeles example). I'm loading vertex information for objects dynamically (just what is needed for an active game area) so there's quite a bit of memory allocation happening for vertices, normals, texture coordinates, indices and texture graphic data... just to name the essentials. I'm quite careful about freeing what is allocated between game areas. Would I be safer setting some caps on array sizes or should I charge bravely forward as I'm going now?

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  • Setting WCF service for multiple client calls

    - by user348255
    Hi all, I have made a WCF service which is defined like this: [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple)] binding is done using netTcpBinding. We support 50+ clients that call the server from time to time. Each client opens a channel using channelfactory once it is loaded and uses that channel for all calls (creates the channel and proxy only once). we have built a small load tester that imitates the client by calling the server by 50 different threads at once (using 50 different channels). when we run this tester, after the 10th client tries to connect, all other client fail connecting. We have set throttling to 100. My questions are: 1. is it correct for each client to create a channel and use it through the client life time? or, do i need to use a using statement for each call to the server (create and distroy a new channel for each call). 2. does the service have a limit of channel connections to it? other then throttling? thanks alot, Guy.

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  • C header file won't compile with C, but will with C++.

    - by Leif Andersen
    I have the following chunk of a header file BKE_mesh.h: /* Connectivity data */ typedef struct IndexNode { struct IndexNode *next, *prev; int index; } IndexNode; void create_vert_face_map(ListBase **map, IndexNode **mem, const struct MFace *mface, const int totvert, const int totface); void create_vert_edge_map(ListBase **map, IndexNode **mem, const struct MEdge *medge, const int totvert, const int totedge); Note that the header file was prepared for the possibility of being used in a C++ file, as it had: #ifdef __cplusplus extern "C" { #endif at the top of the file, and the needed finish at the bottom. But the class implementing it was written in C. Next, whenever I try to #include the header file, I get an odd error. If the file has a .cpp extension, it compiles just fine, no complaints whatsoever. However, if I do: #include "BKE_mesh.h" inside of a file with a .c extension, I get the following errors: expected ')' before '*' token for the two last functions, in specific, the variable: ListBase **map in both classes. (Note that earlier in the header file, it declared, but not defined ListBase). So, my question is: why is this valid C++ code, but not C code? Thank you.

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  • IE textarea wrap bug?

    - by user2227033
    It seems that IE starting from IE7 to IE10 wraps text in the textarea control incorrectly when using \n (or \r\n - doesn't matter - results are the same). Is this a bug in IE or they treat the html standard differently than other browsers - who is right? I have defined: <textarea id="TextArea1" runat="server" style="width: 190px; height: 390px; white-space: normal; word-wrap: normal; overflow: scroll" ></textarea> When I try to add long string like "VeryLongStringEndingWithNewLine\n" by using JavaScript code (obj.value += text;) the text is shown in one line with scroll (this is ok) but added with an additional empty line (\r\n) - why? When I try to add short string like "Short\n" multiple times, again via JavaScript code the text is on the same line (should be on the separate lines because normal wrapping should be applied). Moreover when I do postback then all \r\n's are replaced with spaces (why?) and then text parsed correctly (assuming if I used spaces instead of crlf normal wraping with space only wraps when does not fit in the area). When using FF or Chrome same control behaves correctly - long lines are shown without an additional empty next line, short lines are on the different lines, no replacement with spaces when doing postback. I know I could probably use other options or white space characters, but I feel that above is not correct about IE. Any comments? Mindaugas

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  • Drools - Doing Complex Stuff inside a Rule Condition or Consequence

    - by mfcabrera
    Hello, In my company we are planning to use Drools a BRE for couple of projects. Now we trying to define some best-practices. My question is what should be and shouldn't be done inside a Rule Condition/Consequence. Given that we can write Java directly or call methods (for example From a Global object in the Working Memory). Example. Given a Rule that evaluates a generic Object (e.g. Person) have property set to true. Now, that specific propertie can only be defined for that Object going to the database and fetching that info. So we have two ways of implementing that: Alternative A: Go to the database and fetch the object property (true/false, a code) Insert the Object in the working memory Evaluate the rule Alternative B: Insert a Global Object that has a method that connects to the database and check for the property for the given object. Insert the Object to eval in Working Memory In the rule, call the Global Object and perform the access to the database Which of those is considered better? I really like A, but sometimes B is more straightforward, however what would happen if something like a Exception from the Database is raised? I have seen the alternative B implemented in the Drools 5.0 Book from Packt Publishing,however they are doing a mocking and they don't talk about the actual implications of going to the database at all. Thank you,

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  • SSE (SIMD extensions) support in gcc

    - by goldenmean
    Hi, I see a code as below: include "stdio.h" #define VECTOR_SIZE 4 typedef float v4sf __attribute__ ((vector_size(sizeof(float)*VECTOR_SIZE))); // vector of four single floats typedef union f4vector { v4sf v; float f[VECTOR_SIZE]; } f4vector; void print_vector (f4vector *v) { printf("%f,%f,%f,%f\n", v->f[0], v->f[1], v->f[2], v->f[3]); } int main() { union f4vector a, b, c; a.v = (v4sf){1.2, 2.3, 3.4, 4.5}; b.v = (v4sf){5., 6., 7., 8.}; c.v = a.v + b.v; print_vector(&a); print_vector(&b); print_vector(&c); } This code builds fine and works expectedly using gcc (it's inbuild SSE / MMX extensions and vector data types. this code is doing a SIMD vector addition using 4 single floats. I want to understand in detail what does each keyword/function call on this typedef line means and does: typedef float v4sf __attribute__ ((vector_size(sizeof(float)*VECTOR_SIZE))); What is the vector_size() function return; What is the __attribute__ keyword for Here is the float data type being type defined to vfsf type? I understand the rest part. thanks, -AD

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  • Effective communication in a component-based system

    - by Tesserex
    Yes, this is another question about my game engine, which is coming along very nicely, with much thanks to you guys. So, if you watched the video (or didn't), the objects in the game are composed of various components for things like position, sprites, movement, collision, sounds, health, etc. I have several message types defined for "tell" type communication between entities and components, but this only goes so far. There are plenty of times when I just need to ask for something, for example an entity's position. There are dozens of lines in my code that look like this: SomeComponent comp = (SomeComponent)entity.GetComponent(typeof(SomeComponent)); if (comp != null) comp.GetSomething(); I know this is very ugly, and I know that casting smells of improper OO design. But as complex as things are, there doesn't seem to be a better way. I could of course "hard-code" my component types and just have SomeComponent comp = entity.GetSomeComponent(); but that seems like a cop-out, and a bad one. I literally JUST REALIZED, while writing this, after having my code this way for months with no solution, that a generic will help me. SomeComponent comp = entity.GetComponent<SomeComponent>(); Amazing how that works. Anyway, this is still only a semantic improvement. My questions remain. Is this actually that bad? What's a better alternative?

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  • Why do I get null objects in a many-to-many bag?

    - by Jim Geurts
    I have a bag defined for a many-to-many list: <class name="Author" table="Authors"> <id name="Id" column="AuthorId"> <generator class="identity" /> </id> <property name="Name" /> <bag name="Books" table="Author_Book_Map" where="IsDeleted=0" fetch="join"> <key column="AuthorId" /> <many-to-many class="Book" column="BookId" where="IsDeleted=0" /> </bag> </class> If I return all author objects using something like the following, I will get what initially appeared to be duplicate Author records: Session.Query<Author>().List<Author>() The extra author objects are created when an author is mapped to Book objects that have IsDeleted = 1 and IsDeleted = 0. Rather than creating one Author object with an enumerable that contains only the books with IsDeleted = 0, it will create two author objects. The first author object has a Books enumerable that contains books with IsDeleted = 0. The second author object will contain an enumerable of null book objects. Similarly, if an object only has one book map, and that map points to a book with IsDeleted = 1, then an author object is returned with a Books collection having one null object. I'm thinking part of the problem stems from the map table objects linking to rows that satisfy the where condition on the bag object but do not meet the many-to-many where condition. This is happening with NHibernate version 3.0.0.4980. Is this a configuration issue or something else?

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  • Problem Routing domains subfolder

    - by hkda150
    Hi there, I'm pretty new to ASP.NET MVC and I hope it is not a too silly question. So here it comes. I have ... a ASP.NET MVC application with a domain similar to http://mydomain/mysubfoler1/myappfolder My problem... The problem for me is the routing of my application (it worked fine without using a subfolder after the domain-name). The applications homepage loads not to bad, with css files but without ressources like images (defined in css files) and without jQuery ajax calls similar to /mycontroller/myaction links are only working once (the second time I get a page similar to this link: http://mydomain/mysubfoler1/myappfolder/myController/myController/myAction) Here's my Global.asax contaning the routing: public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.MapRoute( "Default", "{controller}/{action}/{id}", new { controller = "myController", action = "Index", id = "" } defaults ); routes.MapRoute( "Root", "", new { controller = "myController", action = "Index", id = "" } ); } protected void Application_Start() { ViewEngines.Engines.Clear(); ViewEngines.Engines.Add(new MyApplicationWeb.LocalizationWebFormViewEngine()); RegisterRoutes(RouteTable.Routes); //RouteDebug.RouteDebugger.RewriteRoutesForTesting(RouteTable.Routes); } Any suggestions? My first suggestion was to use areas like: "mysubfolder1/myappfolder/{controller}/{action}/{id}" (but without any luck) Thank you very much for your help!

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  • PHP Function parameters - problem with var not being set

    - by Marty
    So I am obviously not a very good programmer. I have written this small function: function dispAdjuggler($atts) { extract(shortcode_atts(array( 'slot' => '' ), $atts)); $adspot = ''; $adtype = ''; // Get blog # we're on global $blog_id; switch ($blog_id) { case 1: // root blog HOME page if (is_home()) { switch ($slot) { case 'top_leaderboard': $adspot = '855525'; $adtype = '608934'; break; case 'right_halfpage': $adspot = '855216'; $adtype = '855220'; break; case 'right_med-rectangle': $adspot = '858222'; $adtype = '613526'; break; default: throw new Exception("Ad slot is not defined"); break; } When I reference the function on a page like so: <?php dispAdjuggler("top_leaderboard"); ?> The switch is throwing the default exception. What am I doing wrong here? Thanks!!

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  • hibernate: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException

    - by user121196
    when saving an object to database using hibernate, sometimes it fails because certain fields of the object exceed the maximum varchar length defined in the database. There force I am using the following approach: 1. attempt to save 2. if getting an DataException, then I truncate the fields in the object to the max length specified in the db definition, then try to save again. However, in the second save after truncation. I'm getting the following exception: hibernate: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails here's the relevant code, what's wrong? public static void saveLenientObject(Object obj){ try { save2(rec); } catch (org.hibernate.exception.DataException e) { // TODO Auto-generated catch block e.printStackTrace(); saveLenientObject(rec, e); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } private static void saveLenientObject(Object rec, DataException e) { Util.truncateObject(rec); System.out.println("after truncation "); save2(rec); } public static void save2(Object obj) throws Exception{ try{ beginTransaction(); getSession().save(obj); commitTransaction(); }catch(Exception e){ e.printStackTrace(); rollbackTransaction(); //closeSession(); throw e; }finally{ closeSession(); } }

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  • Using variables before include()ing them

    - by phenry
    I'm using a file, page.php, as an HTML container for several content files; i.e., page.php defines most of the common structure of the page, and the content files just contain the text that's unique to every page. What I would like to do is include some PHP code with each content file that defines metadata for the page such as its title, a banner graphic to use, etc. For example, a content file might look like this (simplified): <?php $page_title="My Title"; ?> <h1>Hello world!</h1> The name of the file would be passed as a URL parameter to page.php, which would look like this: <html> <head> <title><?php echo $page_title; ?></title> </head> <body> <?php include($_GET['page']); ?> </body> </html> The problem with this approach is that the variable gets defined after it is used, which of course won't work. Output buffering also doesn't seem to help. Is there an alternate approach I can use? I'd prefer not to define the text in the content file as a PHP heredoc block, because that smashes the HTML syntax highlighting in my text editor. I also don't want to use JavaScript to rewrite page elements after the fact, because many of these pages don't otherwise use JavaScript and I'd rather not introduce it as a dependency if I don't have to.

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  • Advanced XPath query

    - by alex
    Hello, I have an XML file that looks like this: <?xml version="1.0" encoding="utf-8" ?> <PrivateSchool> <Teacher id="teacher1"> <Name> teacher1Name </Name> </Teacher> <Teacher id="teacher2"> <Name> teacher2Name </Name> </Teacher> <Student id="student1"> <Name> student1Name </Name> </Student> <Student id="student2"> <Name> student2Name </Name> </Student> <Lesson student="student1" teacher="teacher1" /> <Lesson student="student2" teacher="teacher2" /> <Lesson student="student3" teacher="teacher3" /> <Lesson student="student1" teacher="teacher2" /> <Lesson student="student3" teacher="teacher3" /> <Lesson student="student1" teacher="teacher1" /> <Lesson student="student2" teacher="teacher4" /> <Lesson student="student1" teacher="teacher1" /> </PrivateSchool> There's also a DTD associated with this XML, but I assume it's not much relevant to my question. Let's assume all needed teachers and students are well defined. What is the XPath query that returns the teachers' NAMES, that have at least one student that took more than 10 lessons with them? I was looking at many XPath sites/examples. Nothing seemed advanced enough for this kind of question... Thank you

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  • There is a Default instance of form in VB.Net but not in C#, WHY?

    - by Shekhar_Pro
    I'm just curious to know that there is The (Name) property, which represents the name of the Form class.This property is used within the namespace to uniquely identify the class that the Form is an instance of and, in the case of Visual Basic, is used to access the default instance of the form. Now where this Default Instance come from, why can't C# have a equivalent method to this. Also for example to show a form in C# we do something like this: //Only method Form1 frm = new Form1(); frm.Show(); But in VB.Net we have both ways to do it: //'First common method (used slash because editor wouldn't format it properly) Form1.Show(); //'Second method Dim frm as New Form1(); frm.Show(); My question comes from this first method. What is this Form1, is it an instance of Form1 or the Form1 class itself. Now as i mentioned above the Form name is the Default instance in VB.Net. But we also know that Form1 is a class defined in Designer so how can the names be same for both the Instance and class name. If Form1 is Class then there is no (Static\Shared) method named Show(). So where does this method come from. And finally why C# can't have an equivalent of this. If there some mistake in my question Please let me know *I've checked this on stackoverflow, but couldn't find an answer to this.If you do find then please give a link to it.*

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  • Best way reading from dirty excel sheets

    - by Ten Ton Gorilla
    I have to manipulate some Excel documents with C#. It's a batch process with no user interaction. It's going to parse data into a database, then output nice reports. The data is very dirty and cannot be ready using ADO. The data is nowhere near a nice table format. Best is defined as the most stable(updates less likely to break)/ clear(succinct) code. Fast doesn't matter. If it runs in less than 8 hours I'm fine. I have the logic to find the data worked out. All I need to make it run is basic cell navigation and getvalue type functions. Give me X cell value as string, if it matches Y value with levenshtein distance < 3, then give me Z cell value. My question is, what is the best way to dig into the excel? VSTO? Excel Objects Library? Third Option I'm not aware of?

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  • Random syntactical error in my php code that I can't find

    - by user348538
    Ordinarily I hate coming here with newbie code questions but nobody can find the error with this code. Maybe you guys can :-) <?php defined('SYSPATH') or die('No direct script access.'); /** * to interact with photos * * @author Max Padraig Wolfgang Bucknell-Leahy */ class Model_Photos { private $apiKey = '12664498208a1380fe49fb1b5a238ef0'; private $secret = '03d43dee65a34513'; private $perms = 'read'; private $sigString = 'test'; private $apiSig = md5($_sigString); private $authArray = array('api_key' => $apiKey, 'perms' => $perms, 'api_sig' => $apiSig); private $authArrayImploded = implode('&', $authArray); private $authLink = 'http://www.flickr.com/services/auth/?' . $authArrayImploded; public function get_photos($number = 5) { if(file_exists(APPPATH . 'cache/main_cache.xml') { echo $authLink; } else { echo 'not so good'; /** */ } } } $class = new Model_Photos; $class->get_photos; the error is: Parse error: syntax error, unexpected '(', expecting ',' or ';' in /home/p14s9nnd/public_html/testing.php on line 15 Thank you in advance and sorry Regards, Max

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  • NHibernate - Retrieving Lots of Data Becomes Exponentially Slow

    - by nfplee
    Hi, I have an issue when I retrieve lots of data in NHibernate (such as when producing a report) the page becomes exponentially slower the more data it has to retrieve. I found the following article: http://nhforge.org/blogs/nhibernate/archive/2008/10/30/bulk-data-operations-with-nhibernate-s-stateless-sessions.aspx It explains how doing bulk data operations in NHibernate is slow since the first level cache grows too large and how you should use the IStatelessSession instead. The trouble I have is that I don't wish to tie my application to NHibernate so I've added a wrapper around ISession. I then use Linq as my query mechanism but IStatelessSession does not support Linq (it may do in NHibernate 3 but the Linq provider is not stable as it stands at the moment). I then read that you could do a clear after so many iterations to clear out the first level cache. The problem now is that you can't use lazy loading. The linq provider doesn't allow you to override the mapping defined (or eagerly fetch the additional data) so whenever I grab data which is lazy loaded after I have cleared the session an exception is thrown. I'm completely lost on what do now. I like the ease of producing reports with linq but the limitations of the inbuilt linq provider in NHibernate seem to be holding me back. I'd really appreciate it if someone could show me an alternative approach. Thanks

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  • My project is no longer used - how should I feel?

    - by flybywire
    For the last two years I have been developing and supporting an important project for a big customer. The project included mining data from the customer's existing systems, processing, and displaying and updating in the customer's public home page. The project was defined as crucial by the customer and I was payed good money and flown at the customer's expense to meet key employees. Some months ago, when the project was finished and in maintainance mode, I informed the customer that I am no longer interested in doing it as I had a new opportunity that would not be compatible with my existing customer. I was payed to train one of their employees, flown to meet him, make sure everything works and that he can be safely left in charge of the project. We finished in good terms after I complied with all my obligations and they payed me all they owed me. Some days ago, just out of curiosity, I entered to their website to see how the data continues to be updated and much to my dismay I discovered that the day after my contract was finished my system was "turned off" and it ceased to feed data to the public website. Let's put it clear, there is no issue of money or broken contract here. They are in they full right to do whatever they want with my software. But it is an issue of broken "programmer's ego". Should I feel bad about it (I do). Should I care and check out with my customer if they need some help? Or is it none of my matters?

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  • Magento - Add a button to system.xml with method attached to it

    - by vrnet
    Hi, I have created a module that has an "export like" method running regularly as defined in my module's cron area of the config.xml file. But I'd like to give the user the ability to run this export method on demand by adding a "Run now" button in the system configuration, thus using the system.xml file. It seems that the "frontend type" button may be working as I've tried and it adds a tiny clickable button in the config section. But I am not able to attach a method nor a label on the button itself. I thought about adding a button in the "Grid.php" file of the module but this not what I'd like to do as it does fit with my acl. Below is my system.xml file with the "button" frontend type. Does anyone have a clue on how to : add a label/value to the button add a class to the button add a method to call when the button is clicked Many thanks for your help ! <?xml version="1.0" encoding="UTF-8"?> <config> ... <fields> ... <run translate="label"> <label>Run now</label> <frontend_type>button</frontend_type> <backend_model>SOME BACKEND MODEL</backend_model> <sort_order>20</sort_order> <show_in_default>1</show_in_default> <show_in_website>1</show_in_website> <show_in_store>1</show_in_store> </run> </fields> ... </config>

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  • SQL Server 2008 - Full Text Query

    - by user208662
    Hello, I have two tables in a SQL Server 2008 database in my company. The first table represents the products that my company sells. The second table contains the product manufacturer’s details. These tables are defined as follows: Product ------- ID Name ManufacturerID Description Manufacturer ------------ ID Name As you can imagine, I want to make this as easy as possible for our customers to query this data. However, I’m having problems writing a forgiving, yet powerful search query. For instance, I’m anticipating people to search based on phonetical spellings. Because of this, the data may not match the exact data in my database. In addition, I think some individuals will search by manufacturer’s name first, but I want the matching product names to appear first. Based on these requirements, I’m currently working on the following query: select p.Name as 'ProductName', m.Name as 'Manufacturer', r.Rank as 'Rank' from Product p inner join Manufacturer m on p.ManufacturerID=m.ID inner join CONTAINSTABLE(Product, Name, @searchQuery) as r Oddly, this query is throwing an error. However, I have no idea why. Squiggles appear to the right of the last parenthesis in management studio. The tool tip says "An expression of non-boolean type specified in a context where a condition is expected". I understand what this statement means. However, I guess I do not know how COntainsTable works. What am I doing wrong? Thank you

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  • RadioButtonGroup with each RadioButton added in components?

    - by futureal
    Hi, Working in Flex 3, I have a series of components being rendered on a canvas, each of which should represent a single potential selection, ideally in a RadioButtonGroup. So in my parent canvas I am defining the RadioButtonGroup, and each component provides a single RadioButton. However, this doesn't seem to work. Suppose there is a component called aComponent defined as such: <mx:Canvas ...> ... <mx:RadioButton id="someButton" groupName="myRadioButtonGroup" ... /> </mx:Canvas> The outer canvas: <mx:Canvas ...> ... <mx:Script> public function doesSomething():void { var myComponent:aComponent = new aComponent(); outerCanvas.addChild(myComponent); } </mx:Script> ... <mx:RadioButtonGroup id="myRadioButtonGroup" /> </mx:Canvas> So my guess was that at this point if, say, four of these components were added, the radio buttons would behave in mutually exclusive fashion and I'd be able to access myRadioButtonGroup.selectedValue to get the current selection. However, it doesn't seem to work that way. Is what I'm trying to do even possible, or have I maybe just missed something? Thanks!

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  • How to take a collection of bytes and pull typed values out of it?

    - by Pat
    Say I have a collection of bytes var bytes = new byte[] {0, 1, 2, 3, 4, 5, 6, 7}; and I want to pull out a defined value from the bytes as a managed type, e.g. a ushort. What is a simple way to define what types reside at what location in the collection and pull out those values? One (ugly) way is to use System.BitConverter and a Queue or byte[] with an index and simply iterate through, e.g.: int index = 0; ushort first = System.BitConverter.ToUint16(bytes, index); index += 2; // size of a ushort int second = System.BitConverter.ToInt32(bytes, index); index += 4; ... This method gets very, very tedious when you deal with a lot of these structures! I know that there is the System.Runtime.InteropServices.StructLayoutAttribute which allows me to define the locations of types inside a struct or class, but there doesn't seem to be a way to import the collection of bytes into that struct. If I could somehow overlay the struct on the collection of bytes and pull out the values, that would be ideal. E.g. Foo foo = (Foo)bytes; // doesn't work because I'd need to implement the implicit operator ushort first = foo.first; int second = foo.second; ... [StructLayout(LayoutKind.Explicit, Size=FOO_SIZE)] public struct Foo { [FieldOffset(0)] public ushort first; [FieldOffset(2)] public int second; } Any thoughts on how to achieve this?

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  • Thread mutex behaviour

    - by Alberteddu
    Hi there, I'm learning C. I'm writing an application with multiple threads; I know that when a variable is shared between two or more threads, it is better to lock/unlock using a mutex to avoid deadlock and inconsistency of variables. This is very clear when I want to change or view one variable. int i = 0; /** Global */ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; /** Thread 1. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); /** Thread 2. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); This is correct, I think. The variable i, at the end of the executions, contains the integer 2. Anyway, there are some situations in which I don't know exactly where to put the two function calls. For example, suppose you have a function obtain(), which returns a global variable. I need to call that function from within the two threads. I have also two other threads that call the function set(), defined with a few arguments; this function will set the same global variable. The two functions are necessary when you need to do something before getting/setting the var. /** (0) */ /** Thread 1, or 2, or 3... */ if(obtain() == something) { if(obtain() == somethingElse) { // Do this, sometimes obtain() and sometimes set(random number) (1) } else { // Do that, just obtain(). (2) } } else { // Do this and do that (3) // If # of thread * 3 > 10, then set(3*10) For example. (4) } /** (5) */ Where I have to lock, and where I have to unlock? The situation can be, I think, even more complex. I will appreciate an exhaustive answer. Thank you in advance. —Alberto

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  • Create unique identifier for different row-groups

    - by Max van der Heijden
    I want to number certain combinations of row in a dataframe (which is ordered on ID and on Time) tc <- textConnection(' id time end_yn number abc 10 0 1 abc 11 0 2 abc 12 1 3 abc 13 0 1 def 10 0 1 def 15 1 2 def 16 0 1 def 17 0 2 def 18 1 3 ') test <- read.table(tc, header=TRUE) The goal is to create a new column ("journey_nr") that give a unique number to each row based on the journey it belongs to. Journeys are defined as a sequence of rows per id up until to end_yn == 1, also if end_ynnever becomes 1, the journey should also be numbered (see the expected outcome example). It is only possible to have end_yn == 0 journeys at the end of a collection of rows for an ID (as shown at row 4 for id 3). So either no end_yn == 1 has occured for that ID or that happened before the end_yn == 0-journey (see id == abc in the example). I know how to number using the data.table package, but I do not know which columns to combine in order to get the expected outcome. I've searched the data.table-tag on SO, but could not find a similar problem. Expected outcome: id time end_yn number journey abc 10 0 1 1 abc 11 0 2 1 abc 12 1 3 1 abc 13 0 1 2 def 10 0 1 3 def 15 1 2 3 def 16 0 1 4 def 17 0 2 4 def 18 1 3 4

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  • How can I serialize this .NET Collection item?

    - by Pure.Krome
    Hi folks, I'm trying to xml serialize a POCO view data class into xml. It serializes, but incorrectly generates some xml. eg. (current result .. not the one I'm after) <ReviewListViewData> <reviews> <review>....</review> ... </reviews> </ReviewListViewData> I'm trying to get (notice how I've removed the bad root node?) ... <reviews> <review>....</review> ... </reviews> Class is defined as... public class ReviewListViewData { [XmlArray("reviews")] [XmlArrayItem("review")] public ReviewViewData[] Reviews { get; set; } } and here's a sample way it's called in an ASP.NET MVC ActionMethod :- var reviewListViewData = GetReviewListViewData(...); return XmlResult(reviewListViewData); // (XmlResult referenced from MVCContrib). anyone have any ideas, please?

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