Search Results

Search found 13578 results on 544 pages for 'graphical programming'.

Page 489/544 | < Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >

  • Using GCC (MinGW) to compile OpenGL on Windows

    - by Casey
    I've searched on google and haven't been able to come up with a solution. I would like to compile some OpenGL programming using GCC. In the GL folder in GCC I have the following headers: gl.h glext.h glu.h Then in my system32 file I have the following .dll opengl32.dll glu32.dll glut32.dll If I wanted to write a simple OpenGL "Hello World" and link and compile with GCC, what is the correct process? I'm attempting to use this code: #include <GL/gl.h> #include <GL/glut.h> void display() { glClear(GL_COLOR_BUFFER_BIT); glFlush(); } int main(int argc, char **argv) { glutInit(&argc, argv); glutInitWindowSize(512,512); glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutCreateWindow("The glut hello world program"); glutDisplayFunc(display); glClearColor(0.0, 0.0, 0.0, 1.0); glutMainLoop(); // Infinite event loop return 0; } Thank you in advance for the help.

    Read the article

  • Why does this data YYYY-MM-DD regex fail in Java?

    - by ProfessionalAmateur
    Hello StackOverFlow, My first question and Im excited... I've lurked since go-live and love the site, however I apologize for any newbie errors, formatting, etc... I'm attempting to validate the format of a string field that contains a date in Java. We will receive the date in a string, I will validate its format before parsing it into a real Date object. The format being passed in is in the YYYY-MM-DD format. However I'm stuck on one of my tests, if I pass in "1999-12-33" the test will fail (as it should with a day number 33) with this incomplete pattern: ((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-([12][0-9]|3[01]) However as soon as I add the characters in bold below it passes the test (but should not) ((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-(0[1-9]|[1-9]|[12][0-9]|3[01]) *additional note, I know I can change the 0[1-9]|[1-9] into 0?[1-9] but I wanted to break everything down to its most simple format to try and find why this isn't working. Here is the scrap test I've put together to run through all the different date scenarios: import java.util.regex.Matcher; import java.util.regex.Pattern; public class scrapTest { public scrapTest() { } public static void main(String[] args) { scrapTest a = new scrapTest(); boolean flag = a.verfiyDateFormat("1999-12-33"); } private boolean verfiyDateFormat(String dateStr){ Pattern datePattern = Pattern.compile("((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-(0[1-9]|[1-9]|[12][0-9]|3[01])"); Matcher dateMatcher = datePattern.matcher(dateStr); if(!dateMatcher.find()){ System.out.println("Invalid date format!!! -> " + dateStr); return false; } System.out.println("Valid date format."); return true; } } Ive been programming for ~10 years but extremely new to Java, so please feel free to explain anything as elementary as you see fit.

    Read the article

  • Need guidelines for optimizing WebGL performance by minimizing shader changes

    - by brainjam
    I'm trying to get an idea of the practicality of WebGL for rendering large architectural interior scenes, consisting of 100K's of triangles. These triangles are distributed over many objects, and there are many materials in the scene. On the other hand, there are no moving parts. And the materials tend to be fairly simple, mostly based on texture maps. There is a lot of texture map sharing .. for example all the chairs in scene will share a common map. There is also some multitexturing - up to three textures overlaid in a material. I've been doing a little experimentation and reading, and gather that frequently switching materials during a rendering pass will slow things down. For example, a scene with 200K triangles will have significant performance differences, depending on whether there are 10 or 1000 objects, assuming that each time an object is displayed a new material is set up. So it seems that if performance is important the scene should be sorted by materials so as to minimize material switching. What I'm looking for is guidelines on how to think of the overhead of various state changes, and where do I get the biggest bang for the buck. For example, what are the relative performance costs of, say, gl.useProgram(), gl.uniformMatrix4fv(), gl.drawElements() should I try to write ubershaders to minimize shader switching? should I try to aggregate geometry to minimize the number of gl.drawElements() calls I realize that mileage may vary depending on browser, OS, and graphics hardware. And I'm also not looking for heroic measures. Just some guidelines from people who have already had some experience in making scenes fast. I'll add that while I've had some experience with fixed-pipeline OpenGL programming in the past, I'm rather new to the WebGL/OpenGL ES 2.0 way of doing things.

    Read the article

  • Why is this exception thrown in the visual studio C compiler?

    - by Shane Larson
    Hello. I am trying to get more adept and my C programming and I was attempting to test out displaying a character from the input stream while inside of the loop that is getting the character. I am using the getchar() method. I am getting an exception thrown at the time that the printf statement in my code is present. (If I comment out the printf line in this function, the exception is not thrown). Exception: Unhandled exception at 0x611c91ad (msvcr90d.dll) in firstOS.exe: 0xC0000005: Access violation reading location 0x00002573. Here is the code... Any thoughts? Thank you. PS. I am using the stdio.h library. /*getCommandPromptNew - obtains a string command prompt.*/ void getCommandPromptNew(char s[], int lim){ int i, c; for(i=0; i < lim-1 && (c=getchar())!=EOF && c!='\n'; ++i){ s[i] = c; printf('%s', c); } }

    Read the article

  • Method of transforming 3D vectors with a matrix

    - by Drew Noakes
    I've been doing some reading on transforming Vector3 with matrices, and am tossing up digging deeper into the math and coding this myself versus using existing code. For whatever reason my school curriculum never included matrices, so I'm filling a gap in my knowledge. Thankfully I only need a few simple things, I think. Context is that I'm programming a robot for the RoboCup 3D league. I'm coding it in C# but it'll have to run on Mono. Ideally I wouldn't use any existing graphics libraries for this (WinForms/WPF/XNA) as all I really need is a neat subset of matrix transformations. Specifically, I need translation and x/y/z rotations, and a way of combining multiple transformations into a single matrix. This will then be applied to my own Vector3 type to produce the transformed Vector3. I've read different advice about this. For example, some model the transformation with a 4x3 matrix, others with a 4x4 matrix. Also, some examples show that you need a forth value for the vector's matrix of 1. What happens to this value when it's included in the output? [1 0 0 0] [x y z 1] * [0 1 0 0] = [a b c d] [0 0 1 0] [2 4 6 1] The parts I'm missing are: What sizes my matrices should be Compositing transformations by multiplying the transformation matrices together Transforming 3D vectors with the resulting matrix As I mostly just want to get this running, any psuedo-code would be great. Information about what matrix values perform what transformations is quite clearly defined on many pages, so need not be discussed here unless you're very keen :)

    Read the article

  • Access violations in strange places when using Windows file dialogs

    - by Robert Oschler
    A long time ago I found out that I was getting access violations in my code due to the use of the Delphi Open File and/or Save File dialogs, which encapsulate the Windows dialogs. I asked some questions on a few forums and I was told that it may have been due to the way some programs add hooks to the shell system that result in DLLs getting injected in every process, some of which can cause havoc with a program. For the record, the programming environment I use is Delphi 6 Professional running on Windows XP 32-bit. At the time I got around it by not using Delphi's Dialog components and instead calling straight into comdlg32.dll. This solved the problem wonderfully. Today I was working with memory mapped files for the first time and sure enough, access violations started cropping up in weird parts of the code. I tried my comdlg32.dll direct calls and this time it didn't help. To isolate the problem as a test I created a list box with the exact same files I was using during testing. These are the exact same test files I was selecting from an Open File dialog and then launching my memory mapped file with. I set things up so that by clicking on a file in the list box, I would use that file in my memory mapped file test instead of calling into a comdlg32.dll dialog function to select a test file. Again, the access violatons vanished. To show you how dramatic a fix it was I went from experiencing an access violation within 1 to 3 trials to none at all. Unfortunately, it's going to bite me later on of course when I do need to use file dialogs. Has anyone else dealt with this issue too and found the real culprit? Did any of you find a solution I could use to fix this problem instead of dancing around it like I am now? Thanks in advance.

    Read the article

  • What's wrong with this jQuery fading gallery code?

    - by Meep3D
    So I am creating a fading gallery and am a bit of a noob to javascript (but not to programming). I have no idea what is wrong though. Here's the function in question: /* */ function show_next () { // Hide current $('.s_gallery_images li.s_current').fadeTo(200, .2); $('.s_gallery_images li.s_current').css("border","1px green solid"); // if ($('.s_gallery_images li').hasClass ('.s_current')) { console.log ('Incrementing existing'); // Class already exists $('.s_current:first').removeClass('s_current').next().addClass('s_current'); // Was that the last one? if ($('.s_gallery_images li').hasClass ('.s_current')) { console.log ('Current found'); } else { // Class doesn't exist - add to first $('.s_gallery_images li:first').addClass ('.s_current'); console.log ('Wrapping'); } } else { console.log ('Adding new class'); // Class doesn't exist - add to first $('.s_gallery_images li:first').addClass ('.s_current'); } // Show new marked item $('.s_gallery_images li.s_current').fadeTo(200, .8); } The HTML is a very simple: <ul class="s_gallery_images"> <li><img src="imagename" alt="alt" /></li> <li><img src="imagename" alt="alt" /></li> <li><img src="imagename" alt="alt" /></li> </ul> And it displays the list and the images fine. I am using firebugs console.log for debugging, plus have a class set for s_current (bright border) but nothing happens at all. The firebug console log says: Adding New Class Incrementing Existing Current Found Incrementing Existing Current Found Incrementing Existing Current Found Incrementing Existing Current Found ... to infinity The function is called on a setInterval timer, and as far as I can tell it should be working (and I have done something similar before), but it just isn't happening :(

    Read the article

  • asyncronous call doesn't return json

    - by Rebecca
    I am running wamp on an xp box. I am fairly new to web programming, this is for a student project, and have run out of avenues to try to solve this problem. Problem We have client side JavaScript code that uses GDownloadUrl- from the Google api- to wrap xmlHttpRequest calls to a php server side program that is accessing our database. In my callback program, the result of this call is always " ". However, if I use an alert to display the http:// call, with the arguments, and cut and paste that into my browser, the json I expected is displayed. I zipped my dir containing all the files, and tried it out on another team member's computer, and they were able to get the json in the callback function. Note this is exactly the same code and structure I was using, he just unzipped and ran. So now I'm thinking this is something about Firefox or Wamp? Would this be a config problem? I'm running wamp server 2.0, and Firefox 3.5.8. I have no problems with syncronous php, or reading in files asyncronously. Any help would be greatly appreciated. Rebecca

    Read the article

  • How can i get rid of 0xFEEFEE in VC

    - by egebilmuh
    Hi guys I m programming C for an assingment in VC++ 2008. I simulate adjList for graph implementation. i can readly add edge between two vertex and print the graph. and i want to remove edge between two vertex and print the graph again. whatever i do,i cant print the graph after deleting the edge. i get 0xfeefee :( what is this? and how can i resolve this program. my delete function and print the graph function are illustrated below. void deleteEdge(Graph G, Vertex V, Vertex W) { Edge list,prev,temp; list=V->list; prev=NULL; // while(list!=NULL && list->to->value!=W->value){ prev=list; list=list->next; } // have found the element. if(list!=NULL){ temp=list; // if first element of list is deleted. if(prev==NULL) list=list->next; else prev->next=list->next; // reallocate. free(temp); } } void GRAPHprint(Graph G) { Vertex tmp; Edge list; for(tmp = G->head;tmp!=NULL;tmp=tmp->next) { fprintf(stdout,"V:%d\t",tmp->value); list=tmp->list; while(list!=NULL) { fprintf(stdout,"%d\t",list->to->value); list=list->next; } fprintf(stdout, "\n"); } system("pause"); }

    Read the article

  • OpenCL - incremental summation during compute

    - by user1721997
    I'm absolutelly novice in OpenCL programming. For my app. (molecular simulaton) I wrote a kernel for calculate intermolecular potential of lennard-jones liquid. In this kernel I need to compute cumulative value of the potential of all particles with one: __kernel void Molsim(__global const float* inmatrix, __global float* fi, const int c, const float r1, const float r2, const float r3, const float rc, const float epsilon, const float sigma, const float h1, const float h23) { float fi0; float fi1; float d; unsigned int i = get_global_id(0); //number of particles (typically 2000) if(c!=i) { // potential before particle movement d=sqrt(pow((0.5*h1-fabs(0.5*h1-fabs(inmatrix[c*3]-inmatrix[i*3]))),2.0)+pow((0.5*h23-fabs(0.5*h23-fabs(inmatrix[c*3+1]-inmatrix[i*3+1]))),2.0)+pow((0.5*h23-fabs(0.5*h23-fabs(inmatrix[c*3+2]-inmatrix[i*3+2]))),2.0)); if(d<rc) { fi0=4.0*epsilon*(pow(sigma/d,12.0)-pow(sigma/d,6.0)); } else { fi0=0; } // potential after particle movement d=sqrt(pow((0.5*h1-fabs(0.5*h1-fabs(r1-inmatrix[i*3]))),2.0)+pow((0.5*h23-fabs(0.5*h23-fabs(r2-inmatrix[i*3+1]))),2.0)+pow((0.5*h23-fabs(0.5*h23-fabs(r3-inmatrix[i*3+2]))),2.0)); if(d<rc) { fi1=4.0*epsilon*(pow(sigma/d,12.0)-pow(sigma/d,6.0)); } else { fi1=0; } // cumulative difference of potentials fi[0]+=fi1-fi0; } } My problem is in the line: fi[0]+=fi1-fi0;. In the one-element vector fi[0] are wrong results. I read something about sum reduction, but I do not know how to do it during the calculation. Exist any simple solution of my problem?

    Read the article

  • Android: Error trying to edit button text after thread sleep

    - by Vass
    (programming Android in Eclipse) I am trying to set up a delay in changing the text in a button. I am getting errors only after there is a delay and the text needs to be changed. Here is the simplified code without a while loop: final Button button_target = (Button) findViewById(R.id.button_target); Thread textChange = new Thread(new Runnable() { public void run(){ button_target.setText("fog"); try{ Thread.sleep(3000); }catch(InterruptedException e){} } }); textChange.start(); And now here is the code where a change of text on the button is required after the sleep which now causes and error and exit (forced): final Button button_target = (Button) findViewById(R.id.button_target); Thread textChange = new Thread(new Runnable() { public void run(){ button_target.setText("cat"); try{ Thread.sleep(3000); }catch(InterruptedException e){} button_target.setText("dog"); } }); textChange.start(); what am I doing to cause the error? Is there another method that I should do to be able to invoke a sleep or delay to the thread so that a text change operation can be performed? (the actual code has a while loop but I believe this form puts the error in highlight)

    Read the article

  • Avoid loading unnecessary data from db into objects (web pages)

    - by GmGr
    Really newbie question coming up. Is there a standard (or good) way to deal with not needing all of the information that a database table contains loaded into every associated object. I'm thinking in the context of web pages where you're only going to use the objects to build a single page rather than an application with longer lived objects. For example, lets say you have an Article table containing id, title, author, date, summary and fullContents fields. You don't need the fullContents to be loaded into the associated objects if you're just showing a page containing a list of articles with their summaries. On the other hand if you're displaying a specific article you might want every field loaded for that one article and maybe just the titles for the other articles (e.g. for display in a recent articles sidebar). Some techniques I can think of: Don't worry about it, just load everything from the database every time. Have several different, possibly inherited, classes for each table and create the appropriate one for the situation (e.g. SummaryArticle, FullArticle). Use one class but set unused properties to null at creation if that field is not needed and be careful. Give the objects access to the database so they can load some fields on demand. Something else? All of the above seem to have fairly major disadvantages. I'm fairly new to programming, very new to OOP and totally new to databases so I might be completely missing the obvious answer here. :)

    Read the article

  • FILE* issue PPU side code

    - by Cristina
    We are working on a homework on CELL programming for college and their feedback response to our questions is kinda slow, thought i can get some faster answers here. I have a PPU side code which tries to open a file passed down through char* argv[], however this doesn't work it cannot make the assignment of the pointer, i get a NULL. Now my first idea was that the file isn't in the correct directory and i copied in every possible and logical place, my second idea is that maybe the PPU wants this pointer in its LS area, but i can't deduce if that's the bug or not. So... My question is what am i doing wrong? I am working with a Fedora 7 SDK Cell, with Eclipse as an IDE. Maybe my argument setup is wrong tho he gets the name of the file correctly. Code on request: images_t *read_bin_data(char *name) { FILE *file; images_t *img; uint32_t *buffer; uint8_t buf; unsigned long fileLen; unsigned long i; //Open file file = (FILE*)malloc(sizeof(FILE)); file = fopen(name, "rb"); printf("[Debug]Opening file %s\n",name); if (!file) { fprintf(stderr, "Unable to open file %s", name); return NULL; } //....... } Main launch: int main(int argc,char* argv[]) { int i,img_width; int modif_this[4] __attribute__ ((aligned(16))) = {1,2,3,4}; images_t *faces, *nonfaces; spe_context_ptr_t ctxs[SPU_THREADS]; pthread_t threads[SPU_THREADS]; thread_arg_t arg[SPU_THREADS]; //intializare img_width img_width = atoi(argv[1]); printf("[Debug]Img size is %i\n",img_width); faces = read_bin_data(argv[3]); //....... } Thanks for the help.

    Read the article

  • Can't Display Bitmap of Higher Resolution than CDC area

    - by T. Jones
    Hi there dear gurus and expert coders. i am not gonna start with im a newbie and don't know much about image programming but unfortunately those are the facts :( I am trying to display an image from a bitmap pointer *ImageData which is of resolution 1392x1032. I am trying to draw that at an area of resolution or size 627x474. However, repeated trying doesnt seem to work. It works when I change the bitmap image I created from *ImageData width and height to resolution or size of around 627x474 I really do not know how to solve this after trying all possible solutions from various forums and google. pDC is a CDC* and memDC is a CDC initialized in an earlier method Anything uninitialized here was initialized in other methods. Here is my code dear humble gurus. Do provide me with guidance Yoda and Obi-Wan provided to Luke Skywalker. void DemoControl::ShowImage( void *ImageData ) { int Width; //Width of Image From Camera int Height; //Height of Image From Camera int m_DisplayWidth = 627 ;//width of rectangle area to display int m_DisplayHeight = 474;//height of rectangle area to display GetImageSize( &Width, &Height ) ; //this will return Width = 1392, Height 1032 CBitmap bitmap; bitmap.CreateBitmap(Width,Height,32,1,ImageData); CBitmap* pOldBitmap = memDC.SelectObject((CBitmap*)&bitmap); pDC->BitBlt(22, 24, 627, 474, &memDC, 0, 0, SRCCOPY); memDC.SelectObject((CBitmap*)pOldBitmap); ReleaseDC(pDC); }

    Read the article

  • wxpython: adding panel to wx.Frame disables/conflicts with wx.Frame's OnPaint?!

    - by sdaau
    Hi all, I just encountered this strange situation: I found an example, where wx.Frame's OnPaint is overridden, and a circle is drawn. Funnily, as soon as I add even a single panel to the frame, the circle is not drawn anymore - in fact, OnPaint is not called at all anymore ! Can anyone explain me if this is the expected behavior, and how to correctly handle a wx.Frame's OnPaint, if the wx.Frame has child panels ? Small code example is below.. Thanks in advance for any answers, Cheers! The code: #!/usr/bin/env python # http://www.linuxquestions.org/questions/programming-9/wxwidgets-wxpython-drawing-problems-with-onpaint-event-703946/ import wx class MainWindow(wx.Frame): def __init__(self, parent, title, size=wx.DefaultSize): wx.Frame.__init__(self, parent, wx.ID_ANY, title, wx.DefaultPosition, size) self.circles = list() self.displaceX = 30 self.displaceY = 30 circlePos = (self.displaceX, self.displaceY) self.circles.append(circlePos) ## uncommenting either only first, or both of ## the commands below, causes OnPaint *not* to be called anymore! #~ self.panel = wx.Panel(self, wx.ID_ANY) #~ self.mpanelA = wx.Panel(self.panel, -1, size=(200,50)) self.Bind(wx.EVT_PAINT, self.OnPaint) def OnPaint(self, e): print "OnPaint called" dc = wx.PaintDC(self) dc.SetPen(wx.Pen(wx.BLUE)) dc.SetBrush(wx.Brush(wx.BLUE)) # Go through the list of circles to draw all of them for circle in self.circles: dc.DrawCircle(circle[0], circle[1], 10) def main(): app = wx.App() win = MainWindow(None, "Draw delayed circles", size=(620,460)) win.Show() app.MainLoop() if __name__ == "__main__": main()

    Read the article

  • Hiring my first employee

    - by Ady
    A few years ago I moved to a new job having been programming for 2 years using C#, however this new company was mainly using VB6. I made the case for .NET and won, but one of the consessions I had to make was to use VB.NET and not C# (understandable as most of the other developers were already using VB). Three years later it was time to move on, but when applying for jobs I couldn't get past the recruitment agents. I realised that when they were looking at the basic requirements (5 years experience) that they could not add 2 and 3 together to make 5. They were looking for 5 years in VB or C# not across both. Frustrated I decided to combine my skills with a designer friend and start my own company. After two years of hard graft we are now looking for our first employee (a programmer), and this question has hit me again, but now I see the employers perspective. Why take the risk of someone getting up to speed when you have thousands of applicants to choose from. So my question is this, if I define the requirements to be too narrow, I could miss the really great candidates. But if they are too broad it's going to take ages to go through them all. This will be our first 'employee' so the choice needs to be good, I can't afford to make a mistake and employ someone naff. Another option would be to choose a bright university graduate, and train them up (less of a risk because we can pay them less). What have others done in this situation, and what would you recommend I do?

    Read the article

  • Given 4 objects, how to figure out whether exactly 2 have a certain property

    - by Cocorico
    Hi guys! I have another question on how to make most elegant solution to this problem, since I cannot afford to go to computer school right so my actual "pure programming" CS knowledge is not perfect or great. This is basically an algorhythm problem (someone please correct me if I am using that wrong, since I don't want to keep saying them and embarass myself) I have 4 objects. Each of them has an species property that can either be a dog, cat, pig or monkey. So a sample situation could be: object1.species=pig object2.species=cat object3.species=pig object4.species=dog Now, if I want to figure out if all 4 are the same species, I know I could just say: if ( (object1.species==object2.species) && (object2.species==object3.species) && (object3.species==object4.species) ) { // They are all the same animal (don't care WHICH animal they are) } But that isn't so elegant right? And if I suddenly want to know if EXACTLY 3 or 2 of them are the same species (don't care WHICH species it is though), suddenly I'm in spaghetti code. I am using Objective C although I don't know if that matters really, since the most elegant solution to this is I assume the same in all languages conceptually? Anyone got good idea? Thanks!!

    Read the article

  • Python: Beginning problems

    - by Blogger
    ok so basically i very new to programming and have no idea how to go about these problems help if you will ^^ Numerologists claim to be able to determine a person’s character traits based on the “numeric value” of a name. The value of a name is determined by summing up the values of the letters of the name, where ‘a’ is 1, ‘b’ is 2, ‘c’ is 3 etc., up to ‘z’ being 26. For example, the name “Zelle” would have the value 26 + 5 + 12 + 12 + 5 = 60 (which happens to be a very suspicious number, by the way). Write a program that calculates the numeric value of a single name provided as input. Word count. A common utility on Unix/Linux systems is a small program called “wc”. This program counts the number of lines, words (strings of characters separated by blanks, tabs, or new lines), and characters in a file. Write your own version of this program. The program should accept a file name as input and then print three numbers showing the count of lines, words, and characters in the file.

    Read the article

  • Using boost asio for pub/sub style tcp in a game loop

    - by unohoo
    I have been reading through the boost asio documentation for a couple of hours now, and while I think the documentation is really great, I am still left a bit confused on how to implement the system that I need. I have to stream info, from a game engine, to a list of computers over tcp. One snag is that, unlike traditional pub/sub, the computer that does the distribution of info is actually the computer that has to connect to the subscribers as well (instead of the subscribers registering with the publisher). This is done via a config file - a list of ip's/ports along with the data that they each require. The subscribers listen, but do not know the ip of the publisher. (As a side note, I'm quite new to network programming, so maybe I'm missing something .. but it's strange that I do not find much information regarding this style of "inverted" client-server model..) I am looking for suggestions for the implementation of such a system using boost asio. Of course I have to integrate the networking into an already existing engine, so with regards to that: What would be a good way to handle messages being sent to multiple computers every frame? Use async_write, call io_service.run and then reset every frame? Would having io_service.run have its own thread be better? Or should I just use threads and use blocking writes?

    Read the article

  • How to pass a function in a function?

    - by SoulBeaver
    That's an odd title. I would greatly appreciate it if somebody could clarify what exactly I'm asking because I'm not so sure myself. I'm watching the Stanford videos on Programming Paradigms(that teacher is awesome) and I'm up to video five when he started doing this: void *lSearch( void* key, void* base, int elemSize, int n, int (*cmpFn)(void*, void*)) Naturally, I thought to myself, "Oi, I didn't know you could declare a function and define it later!". So I created my own C++ test version. int foo(int (*bar)(void*, void*)); int bar(void* a, void* b); int main(int argc, char** argv) { int *func = 0; foo(bar); cin.get(); return 0; } int foo(int (*bar)(void*, void*)) { int c(10), d(15); int *a = &c; int *b = &d; bar(a, b); return 0; } int bar(void* a, void* b) { cout << "Why hello there." << endl; return 0; } The question about the code is this: it fails if I declare function int *bar as a parameter of foo, but not int (*bar). Why!? Also, the video confuses me in the fact that his lSearch definition void* lSearch( /*params*/ , int (*cmpFn)(void*, void*)) is calling cmpFn in the definition, but when calling the lSearch function lSearch( /*params*/, intCmp ); also calls the defined function int intCmp(void* elem1, void* elem2); and I don't get how that works. Why, in lSearch, is the function called cmpFn, but defined as intCmp, which is of type int, not int* and still works? And why does the function in lSearch not have to have defined parameters?

    Read the article

  • How to debug PHP?

    - by NutMotion
    Anyone's been trying himself at object oriented programming ? Most probably every developer I guess:D I for one have never studied OO design patterns thoroughly, and trying to put it all together now does prove at times thrilling, and many times frustrating also. Even more so when trying to do it in : PHP! All-in-all, my boss asked me to add some Database persistence functions to her server, but most of all, she asked me to translate her already working procedural code into a working Object Oriented code. Here I am, still standing on my PHP OO project. I'm (already) fed up with this "file logging only" PHP capability. I believe there must be some (free or not too much expansive) PHP debugging utility ? I've heard about Zend Studio and PHPEd so far, which didn't quite do the trick for whatever reasons. WIRCW("Which I don't Remember Correctly Why" lol) What say yé? on debugging PHP ? Is there a tool that provides a good debug mode? what's more, don't forget I'm not speaking about the classical web Request/response model. Talking about a debugging facility which can enable you to trigger a web service (aka client request) and go into debug mode on the SOAP web service side. Thks for any input.

    Read the article

  • How do the size standard libraries compare for different languages

    - by Roman A. Taycher
    Someone was recently raving about how great jQuery was and how it made javascript into a pleasure and also how the whole source code was so small(and one file). I looked it up on www.ohloh.net/ and it said it was about 30,000 lines of javascript, when I tired curl piped to wc it said about 5000 lines(strange discrepancy that, maybe test suites, ect?). I thought well it isn't that strange since javascript from what I've heard has a lot of fun dynamic tricks, so you can probably get away with a small library. But then I thought what about other high level languages, the ones with large standard libraries and wondered how big the standard are for python/ruby/haskell/pharo(smalltalk)/*ml/ect. (libraries not vm stuff to the degree its possible to separate it) Anybody know? Any details (comment/blank/code lines , test code lines, lines in language vs lines in ffi/byte-code) are appreciated! edit: ps. since it started this me asking about jQuery as a bonus if you could please list the size of mega frameworks, a megaframewok provides so much that people using an x megaframework in language y might sometimes refer to programming in xy or even x rather then in y (ie. : qt, jQuery, etc.).

    Read the article

  • Why doesn't my test run tearDownAfterTestClass when it fails

    - by Memor-X
    in a test i am writing the setUpBeforeTests creates a new customer in the database who is then used to perform the tests with so naturally when i finish the test i should get rid of this test customer in tearDownAfterTestClass so that i can create then anew when i rerun the test and not get any false positives how when the tests all run fine i have no problem but if a test fails and i go to rerun it my setUpBeforeTests fails because i check for mysql errors in it like this try { if(!mysqli_query($connection,$query)) { $this->assertTrue(false); } } catch (Exception $exc) { $msg = '[tearDownAfterTestClass] Exception Error' . PHP_EOL . PHP_EOL; $msg .= 'Could not run query - '.mysqli_error($connection). PHP_EOL;; $this->fail($msg); } the error i get is that there is a primary key violation which is expected cause i'm trying to create a new customer using the same data (primary key is on email which is also used to log in) however that means when the test failed it didn't run tearDownAfterTestClass now i could just move everything in tearDownAfterTestClass to the start of setUpBeforeTests however to me that seems like bad programming since it defeates the purpose of even have tearDownAfterTestClass so i am wondering, why isn't my tearDownAfterTestClass running when a test fails NOTE: the database is a fundamental part of the system i'm testing and the database and system are on a separate development environment not the live one, the backup files for the database are almost 2 GBs and takes almost 1/2 an hour to restore, the purpose of the tear down is to remove any data we have added because of the test so that we don't have to restore the database every time we run the tests

    Read the article

  • OOP - Handling Automated Instances of a Class - PHP

    - by dscher
    This is a topic that, as a beginner to PHP and programming, sort of perplexes me. I'm building a stockmarket website and want users to add their own stocks. I can clearly see the benefit of having each stock be a class instance with all the methods of a class. What I am stumped on is the best way to give that instance a name when I instantiate it. If I have: class Stock() { ....doing stuff..... } what is the best way to give my instances of it a name. Obviously I can write: $newStock = new Stock(); $newStock.getPrice(); or whatever, but if a user adds a stock via the app, where can the name of that instance come from? I guess that there is little harm in always creating a new child with $newStock = new Stock() and then storing that to the DB which leads me to my next question! What would be the best way to retrieve 20 user stocks(for example) into instances of class Stock()? Do I need to instantiate 20 new instances of class Stock() every time the user logs in or is there something I'm missing? I hope someone answers this and more important hope a bunch of people answer this and it somehow helps someone else who is having a hard time wrapping their head around what probably leads to a really elegant solution. Thanks guys!

    Read the article

  • How to link pnglite library in c?

    - by zaplec
    Hi, I installed from kubuntu's package management this handy pnglite library. It contains just one header file "pnglite.h" and one object file "pnglite.o". I have found out where those files are, but I don't know how to link them. I'm using netbeans, but don't know how to link them in there. Also I don't understand how to link them at console. I have a little test program that I would like to test, but I get the error message "undefined reference to function: XXXXXXX". Both netbeans and at console I'm using gcc. That header file is in /usr/include directory, object file is in /usr/lib directory and my test program is under my programming directory at my home directory. Should I put that header and object into the same directory as where my source is? Or is there a way to link them from their current locations? I know that it should be possible to link them from where they are at the moment and I would like to know and understand how to do that. Any help will be appreciated :)

    Read the article

< Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >