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  • Another dynamic memory allocation bug.

    - by m4design
    I'm trying to allocate memory for a multidimensional array (8 rows, 3 columns). Here's the code for the allocation (I'm sure the error is clear for you) char **ptr = (char **) malloc( sizeof(char) * 8); for (i = 0; i < 3; i++) ptr[i] = (char *) malloc( sizeof(char) * 3); The crash happens when I reference this: ptr[3][0]; Unhandled exception at 0x0135144d in xxxx.exe: 0xC0000005: Access violation writing location 0xabababab. Are there any recommended references/readings for this kind of subject? Thanks.

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  • Building and rendering a bitmap from a double array

    - by Ami
    I'm new to c# and I'm sure I'm missing something simple here. I'm trying to build a bitmap from integer values (0-255) in a double array and then render it in a PictureBox. I think my Bitmap is getting generated but it isn't displaying in my PictureBox. Bitmap bmp = new Bitmap(image_width, image_height); Color pxl_color = new Color(); for (int i = 0; i < image_width; i++) { for (int j = 0; j < image_height; j++) { pxl_color = Color.FromArgb(array_bitmap[i][j]); bmp.SetPixel(i, j, pxl_color); } } PictureBox1.Image = bmp; Thanks in advance.

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  • How do I get a MessageBox like information window to appear in Java?

    - by John McClane
    I'm learning Java and I have no idea how to do this. I dragged a button on the form in Netbeans, double clicked it and it created this event: @Action public void HelloClickMethod() { JOptionPane.showMessageDialog(this, "The message!", "This is supposed to be the MessageBox title."); } This is the exception the IDE brings up. Cannot find symbol. Symbol: showMessageDialog() Edit 1 Now I changed it to this: @Action public void HelloClickMethod() { JOptionPane.showMessageDialog(this, "The message!", "This is supposed to be the MessageBox title.",JOptionPane.ERROR_MESSAGE); } However the IDE is saying I have an error in the word 'this'. "Cannot find symbol". I don't understand. Why is it so dificult and why are the errors so esoteric. :P

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  • "_FILE_AND_LINE_ is not defined in this scope" (compiling RakNet NAT examples in OS X)

    - by Michael F
    Hello! I'm working on a RakNet-based project (using 3.8 on OS X 10.6), and I'm trying to work through the various examples that demonstrate the parts of RakNet I want to use. For the "NatCompleteClient" example, I've imported the source into a command-line project in XCode, along with the UPNP dependency. At compile time I've had a few errors in the UPNP section, though, and I can't find any guidance on this. In UPNPPortForwarder.mm, there are 7 lines that use _FILE_AND_LINE_, and the compiler is not happy; for example on line 232: foundInterfaces.Deallocate(r1,_FILE_AND_LINE_); causes: UPNPPortForwarder.mm:232: error: '_FILE_AND_LINE_' was not declared in this scope Can anyone tell me what this is all about? That variable doesn't seem to get talked about very often... or Google doesn't like to find it.

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  • How to corelate gtk.ListStore items with my own models

    - by Victor Stanciu
    Hello, I have a list of Project objects, that I display in a GTK TreeView. I am trying to open a dialog with a Project's details when the user double-clicks on the item's row in the TreeView. Right now I get the selected value from the TreeView (which is the name of the Project) via get_selection(), and search for that Project by name in my own list to corelate the selection with my own model. However, this doesn't feel quite right (plus, it assumes that a Project's name is unique), and I was wondering if there is a more elegant way of doing it.

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  • Would it be faster to use CMS for building the first site in ASP.NET?

    - by rem
    I need an opinion and advise from experienced ASP.NET people, what way to go. Assuming that a developer has some practical background with HTML/JavaScript/PHP on one side and some .NET/C#/WPF experience on the other side. No previous hands on experience with ASP.NET - only theory and some read books on the topic. The task is to build ASP.NET web site with User Managment functionality (user authentication, user account, user buying history, user points and so on) and E-commerce functionality with shopping cart, checkout and all needed for this. Is it worth, i.e. will it be faster, more reliable and secure in the result to use a ASP.NET CMS system (for example Sitefinity from Telerik as declared developer friendly) to build such first site? In what case the learning curve will be more steep and it will take more time to achieve similar results? Notes to take into consideration: 1) Price of the CMS matters not very much 2) E-commerce module should be written from scratch in any case (and integrated in case of using CMS) due to very specific requirements

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  • What is a really simple explanation of unit testing?

    - by ensnare
    I've never done any unit testing before, and would like to learn what it is and how it can be useful in my Python code. I've read through a few Python unit testing tutorials online but they're all so complicated and assume an extended programming background. I'm using Python with Pylons to create a simple web app. Any simple examples would be greatly appreciated. Thanks!

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  • Java cannot find symbol enum

    - by JDelage
    Hi, I'm modeling a chess game on Java, and I'm having some problem. Here's what the code looks like (the relevant parts): Enum class Couleur.java: public enum Couleur {BLANC, NOIR} Piece.java: public abstract class Piece { (...) public Piece(Couleur couleurParam){ this.couleurPiece = couleurParam; } (...) } And finally Tour.java: public class Tour extends Piece { (...) public Tour(Couleur couleurParam){ super(couleurParam); } (...) } All the .java files are in the same folder. Yet at compile I get a "cannot find symbol symbol : variable NOIR location: class Plateau" (Plateau is the class that instantiates Tour.) Can anyone help me figure out what's wrong here? Many thanks, JDelage

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  • run multiple programs in linux

    - by Betamoo
    I am trying to write a .sh file that runs many programs simultaneously I tried this prog1 prog2 But that runs prog1 then waits until prog1 ends and then starts prog2... So how can I run them in parallel? Thanks

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  • C++: Cannot convert from foo& to foo*

    - by Rosarch
    I have a method: odp(foo& bar); I'm trying to call it: foo baz; odp(&baz); I get a compiler error: error C2664: "odp" cannot convert parameter 1 from 'foo *' to 'foo &' What am I doing wrong? Aren't I passing in a reference to baz? UPDATE: Perhaps I have a misconception about the relationship between pointers and references. I thought that they were the same, except references couldn't be null. Is that incorrect?

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  • C#- Console Program Ideas for Noob

    - by user335932
    So, Im a beginning C# programmer. I know basic syntax and simple things like if statements and loops(methods and classes too). I've only used console apps right now havent bothered with windows forms yet. So any simple app ideas that introduce new things important for C# programming. Also, NO tutorials. I want to make all by myself.

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  • Background Image w/Quartz Drawing

    - by James
    I'm using Quartz to do some basic drawing. I recently decided I wanted a background image for my app. So I went into my XIB file and added a UIImageView and set the background, looks good. However, when I run it, the Z-Index of the image is above my drawing. I googled a bit and found that you can do Layout Send to Back in IB...but that option is grayed out to me when I have my UIImageView selected. Is there an easy way to move this UIImageView permanently to the background? Is there perhaps an alternate method to doing this that I should consider? Thanks

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  • Why won't the following haskell code compile?

    - by voxcogitatio
    I'm in the process of writing a small lisp interpreter in haskell. In the process i defined this datatype, to get a less typed number; data Number = _Int Integer | _Rational Rational | _Float Double deriving(Eq,Show) Compiling this fails with the following error: ERROR "types.hs":16 - Syntax error in data type declaration (unexpected `|') Line 16 is the line w. the first '|' in the code above.

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  • How to sanely read and dump structs to disk when some fields are pointers?

    - by bp
    Hello, I'm writing a FUSE plugin in C. I'm keeping track of data structures in the filesystem through structs like: typedef struct { block_number_t inode; filename_t filename; //char[SOME_SIZE] some_other_field_t other_field; } fs_directory_table_item_t; Obviously, I have to read (write) these structs from (to) disk at some point. I could treat the struct as a sequence of bytes and do something like this: read(disk_fd, directory_table_item, sizeof(fs_directory_table_item_t)); ...except that cannot possibly work as filename is actually a pointer to the char array. I'd really like to avoid having to write code like: read(disk_df, *directory_table_item.inode, sizeof(block_number_t)); read(disk_df, directory_table_item.filename, sizeof(filename_t)); read(disk_df, *directory_table_item.other_field, sizeof(some_other_field_t)); ...for each struct in the code, because I'd have to replicate code and changes in no less than three different places (definition, reading, writing). Any DRYer but still maintainable ideas?

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  • Java: how to have global values inside a class?

    - by HH
    I want less methods. I want a common global TestClass from which I could use any of its value inside the class. import java.util.*; import java.io.*; public class TestClass { TestClass(String hello){ String hallo = hello; String halloSecond = "Saluto!"; } public static void main(String[] args) { TestClass test = new TestClass("Tjena!"); System.out.println("I want "Tjena!": " + test.hallo); TestClass testSecond = new TestClass("1"); System.out.println("I want Saluto!:" + test.halloSecond); System.out.println("I want Saluto!:" + testSecond.halloSecond); // How can I get glob.vars like the "Saluto!"? } }

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  • Which MS technologies would be suited for a data intensive application?

    - by steve.tse
    I'm a junior VB.net developer with little application design knowledge. I've been reading a lot of material online regarding different design patterns, frameworks, and methodologies. It's become a bit confusing for me. Right now I'm trying to decide on what language would be best suited to convert an existing VB6 application (with SQL server backend.) I need to update the UI and add more user functionality and reporting capabilities. Initially I was thinking of using WPF and attempting the MVVM model for this big project. Reports would be generated from SSRS. A peer suggested using ASP.net and I don't have enough experience to determine what would be better. The senior programmers here are stuck on using VB6 and don't have any input on what to use. They are encouraging me to use the latest technologies. This application would be for ~20 users in a central location. Ideally I would stick to a Microsoft .net language. Current interface is similar to a datagrid table where the user would click in to see the detail of each record. They would need to have multiple records open at any given time. I look forward to all the advice I can get. EDIT 2010/04/22 2:47 PM EST What is your audience? Internal clients within an intranet How complex are the interactions you expect to implement? not very... displaying data from SQL server to UI. Allow user updates to said data. Typically just one user modifying a record. Do you require near real-time data updates? no How often do you expect to update the application after the first release? twice/year Do you expect a well-defined set of client platforms? Yes, windows xp environment, potentially upgrading to Win7. Currently in IE.6 moving to IE7 or 8 within a couple of months. Do users need access from anywhere? No, just from their PC.

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  • Unexpected behaviour of Order by clause

    - by Newbie
    I have a table which looks like Col1 col2 col3 col4 col5 1 5 1 4 6 1 4 0 3 7 0 1 5 6 3 1 8 2 1 5 4 3 2 1 4 The script is declare @t table(col1 int, col2 int, col3 int,col4 int,col5 int) insert into @t select 1,5,1,4,6 union all select 1,4,0,3,7 union all select 0,1,5,6,3 union all select 1,8,2,1,5 union all select 4,3,2,1,4 If I do a sorting (ascending), the output is Col1 col2 col3 col4 col5 0 1 5 6 3 1 4 0 3 7 1 5 1 4 6 1 8 2 1 5 4 3 2 1 4 The query is Select * from @t order by col1,col2,col3,col4,col5 But as can be seen that the sorting output is wrong (col2 to col5). I want the output to be every column being sorted in ascending order i.e. Col1 col2 col3 col4 col5 0 1 0 1 3 1 3 1 1 4 1 4 2 3 5 1 5 2 4 6 4 8 5 6 7 Why so and how to overcome this? Thanks in advance

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  • NZEC Run time Error Occured

    - by madan
    import math def gen_caller(a): for z in a: x,y=z if x==1: x=2 if y>=x and y-x<=100000: for i in range(x,y+1): flag=0 for j in range(2,(long(math.sqrt(i))+1)): if(i%j==0): flag=1 break if flag==0: print i print "" n=(int(raw_input())) gen_caller([[(long(raw_input())) for j in range(0,2)] for i in range(0,n) if n<=10])

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  • jQuery: Stopping a periodic ajax call?

    - by Legend
    I am writing a small jQuery plugin to update a set of Divs with content obtained using Ajax calls. Initially, let's assume we have 4 divs. I am doing something like this: (function($) { .... .... //main function $.fn.jDIV = { init: function() { ... ... for(var i = 0; i < numDivs; i++) { this.query(i); } this.handlers(); }, query: function(divNum) { //Makes the relevant ajax call }, handlers: function() { for(var i = 0; i < numDivs; i++) { setInterval("$.fn.jDIV.query(" + i + ")", 5000); } } }; })(jQuery); I would like to be able to enable and disable a particular ajax query. I was thinking of adding a "start" and "stop" instead of the "handlers" function and subsequently storing the setInterval handler like this: start: function(divNum) { divs[divNum] = setInterval("$.fn.jDIV.query(" + i + ")", 5000); }, stop: function(divNum) { clearInterval(divs[divNum]); } I did not use jQuery to setup and destroy the event handlers. Is there a better approach (perhaps using more of jQuery) to achieve this?

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  • [Python] OR in regular expression?

    - by www.yegorov-p.ru
    Hello. I have text file with several thousands lines. I want to parse this file into database and decided to write a regexp. Here's part of file: blablabla checked=12 unchecked=1 blablabla unchecked=13 blablabla checked=14 As a result, I would like to get something like (12,1) (0,13) (14,0) Is it possible?

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  • vector related memory allocation question

    - by memC
    hi all, I am encountering the following bug. I have a class Foo . Instances of this class are stored in a std::vector vec of class B. in class Foo, I am creating an instance of class A by allocating memory using new and deleting that object in ~Foo(). the code compiles, but I get a crash at the runtime. If I disable delete my_a from desstructor of class Foo. The code runs fine (but there is going to be a memory leak). Could someone please explain what is going wrong here and suggest a fix? thank you! class A{ public: A(int val); ~A(){}; int val_a; }; A::A(int val){ val_a = val; }; class Foo { public: Foo(); ~Foo(); void createA(); A* my_a; }; Foo::Foo(){ createA(); }; void Foo::createA(){ my_a = new A(20); }; Foo::~Foo(){ delete my_a; }; class B { public: vector<Foo> vec; void createFoo(); B(){}; ~B(){}; }; void B::createFoo(){ vec.push_back(Foo()); }; int main(){ B b; int i =0; for (i = 0; i < 5; i ++){ std::cout<<"\n creating Foo"; b.createFoo(); std::cout<<"\n Foo created"; } std::cout<<"\nDone with Foo creation"; std::cout << "\nPress RETURN to continue..."; std::cin.get(); return 0; }

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  • how to start learning Java scripting

    - by antriksh
    Dear All, I am experienced in the technical support like Linux, oracle, sunos etc and but if i say scripting i know little bit of bash. Now i promoted to manage technical engineers inuding some java script developers, so i want to learn java scripting so that i can understand engineers. Hope you understand. Can you please advise me how can i start java scripting and point me to some simple docs and examples.

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