#include<stdlib.h> #include<stdio.h> int main(){ int row; int col; int i=1; double ** doubleNode; // *(*(doubleNode+row)+coln) doubleNode=malloc(sizeof(double)*4); *doubleNode=malloc(sizeof(double *)*4); for(row=0; row <4; row++){ for(col =0; col<4;col++){ *(*(doubleNode+row)+col)=i; i++; } } free(doubleNode)...
I am a beginner in C# I wonder how to write in C# C's static void example(const char *filename) { FILE *f; outbuf_size = 10000; outbuf = malloc(outbuf_size); f = fopen(filename, "wb"); if (!f) { fprintf(stderr, "could not open %s\n", filename); exit(1); } fwrite(outbuf, 1, outbuf_size, f); fclose(f); } Plas...
I have an OpenCV project mixing Python and C. After changing to OpenCV 2.1, my calls to C code are not working any more, probably because OpenCV is no more using SWIG bindings. From Python, I was used to call a C function with the following prototype: int fast_support_transform(CvMat * I, CvMat * N,...); Now, I get the following err...
I,m using gcc compiler(MinGW) on Windows XP.I created a .dll library libdir.dll than I tried to build a program that is using that library. I don't want to put that .dll file into System or System32 folder nor to set path to it in PATH variable, what i want is to give that information to the program itself. I know there is a -R and -rpat...
How can I access to the contents of a zip file? I'm trying write a program in C and I want use the libraries used by zip. ...
I started implementing something similar to task switching in my app on atmega8. The main idea is that there's a pointer to a "current screen" structure. The "current screen" contains handlers for refreshing the screen, handling buttons and interrupts. Unfortunately I discovered that changing a function pointer is done in done in 2 oper...
What is a fast way to compute the (long int) ceiling(log_2(i)), where the input and output are 64-bit integers? Solutions for signed or unsigned integers are acceptable. I suspect the best way will be a bit-twiddling method similar to those found here, but rather than attempt my own I would like to use something that is already well test...
Let's say I have a variadic function foo(int tmp, ...), when calling foo function I need to know how many arguments there are. I'm aware of two ways of finding out how many arguments there are: Use a final argument when calling foo, like -1, so your function call will be like this: foo(tmp, 1, 2, 9, -1) and when you are inside foo and...
How to implement saved-set user id using C language? ...
I am trying to write a custom propercase user defined function for mysql so i took the str_ucwords function from http://www.mysqludf.org/index.php as an example to build my own. my_bool str_ucwords_init(UDF_INIT *initid, UDF_ARGS *args, char *message) { /* make sure user has provided exactly one string argument */ if (args->arg_...
I'm making a vector drawing application and noticed that Anti Grain Geometry have an example that does exactly what I want. http://www.antigrain.com/demo/index.html then below there is an example on perspective for Win32. I don't understand their cpp file. Based on this example. If I have a bunch of verticies to form an object, like thei...
Hi, i want to floor a double by its decimal place with variable decimal length (in iphone sdk). here some examples to show you what i mean NSLog(@"%f",[self floorMyNumber:34.52462 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52662 toPlace:2); // should return 34.52 NSLog(@"%f",[self floorMyNumber:34.52432 toP...
// Arg0 - Map, Arg1 - X, Arg2 - Y, Arg3 - Distance, Arg4 - MaxDistance var xx,yy,dist, x1, y1, dir, maxdist, obj, res, map; map = argument0 x1 = argument1 y1 = argument2 dir = argument3 maxdist = argument4 dist = 0 do { dist+=1 xx = x1+round(lengthdir_x(dist,dir)) yy = y1+round(lengthdir_y(dist,dir)) }...
GNU libc's backtrace and In-circuit emulators/debuggers are not always available when porting code to a new platform, especially when the target is a micro C compiler such as for the Z80. (Typically a program bug would "just hang" somewhere, or crash the gadget.) Is there an alternative to the classic "wolf fencing" method of manually i...
In C and embedded, one frequently uses enumerated constants where every value is a bit mask with exactly 1-bit set. (e.g. 0x0001, 0x0002, 0x0004, etc.) Is there a standard name for this type of bitmask? I've seen them referred to as flags, but more in passing than as a standard definition. I know it sounds snobbish, but "flags" doesn't r...
I have a struct called Point (which happens to be a Python Extension) that looks like this: struct Point { PyObject_HEAD // Macro that expands to include a few more members double x; double y; }; And I have another struct that will hold a bunch of these in two arrays: struct Polygon { int length; Point **vertex...
I'm doing something similar to the following code. I have already gone through AddtoStructFunction() filling mystruct once. Now, what I would like to do is to append every new entry directly to the mystruct without having to free mystruct and iterate over again the whole g_hash_table containing the new key(s) to insert them into mystruct...
Very simple problem, but can't seem to solve it. I'm probably just not thinking right. So I'm using C and I need to be able to sort some images I download into two rows. Like this: http://i.imgur.com/lWkEO.png So my program will, say, download 30 images and it has to sort it into these two rows just like you see in the picture. So I know...
I asked a question regarding Bi linear transformations and received this answer: From that very page you posted, there's a link to the source code. I'll explain the bilinear transformation in http://www.antigrain.com/__code/include/agg_trans_bilinear.h.html The idea here is to find a transformation of the form: output_x = a * input_x...
Many embedded engineers use c++, but some argue it's bad because it's "object oriented"? Is it true that being object oriented makes it bad for embedded systems, and if so, why is that really the case? Edit: Here's a quick reference for those who asked: so we prefer people not to use divide ..., malloc ..., or other object ori...