Thread: Memory allocation question

Originally Posted by dakarn

I switched up my code a little bit but my understanding may be faulty here:

A = (double **)calloc(16, sizeof(double *));
Allocates enough memory for 16 doubles?

No, it allocates 16 rows (that don't yet have any memory in it).

Code:

	

		

			

			
				for(row=0;row<4;row++)
{
A[row] = (double *)calloc(4, sizeof(double *));
if(A[row]==NULL)
{
printf("(main) calloc failed in double *A[]\n");
exit(4);
}
}
			
		
	

allocates memory for 4 doubles for each row of 4?

Thanks for the replies tabstop!

It allocates memory for four pointers-to-double, not four doubles. (This may be enough memory, but is not guaranteed to be.)