Initializing Dynamic (Allocated) Array?
Hello.
Although I've already spotted this thread "Initializing a 2D array dynamically allocated" I could not understand why following code gets not compiled with GCC (C99-standard):
Code:#include <stdio.h> #include <stdlib.h> int main (void) { int *array = malloc(2*sizeof(int)); array = {2,1};//error: expected expression before ‘{’ token free(array); return EXIT_SUCCESS; }
Way off. I strongly suggest that you go read a C language reference first before trying this. Basics, basics, basics...Originally Posted by Mekeor
Last edited by Sebastiani; 02-17-2011 at 03:35 PM. Reason: (emphasis mine)
Code:#include <cmath> #include <complex> bool euler_flip(bool value) { return std::pow ( std::complex<float>(std::exp(1.0)), std::complex<float>(0, 1) * std::complex<float>(std::atan(1.0) *(1 << (value + 2))) ).real() < 0; }
If you spotted the thread, actually read it and noted that people said that it was not possible with a dynamically-allocated array, why did you
a. insist on trying anyway
b. complain when what you were told would happen actually happened?
Alternative?
All right. Thank you very much for your replies. I've just one question left over:
Do you know an alternative way to achieve my aim?
Nope, and it really doesn't make sense to. If you know how big you want your array to be at compile time (obviously you do, since you initialize exactly that number of elements), there's no point in dynamic memory, you would just use a regular array. Dynamic memory is for allocating stuff at run time, implying you don't know how many things you have until you're running your program, thus you can't have a valid initializer at compile time.
You're trying to use the wrong tool for the wrong job.
Should be possible to use a compound literal with memcpy, but it will end up being more to write and be less clear than to simply do it manually.
Do explain.
What I meant was, (half jokingly) that this is a more complicated and in reality not practical solution:
compared to this:Code:memcpy(array, ((int []){2,1}), sizeof(int)*2);
Code:array[0] = 2; array[1] = 1;
