How to initialize large size of array to 0 in C [duplicate]

Question

I am trying to initialize all columns and rows of array of large size to 0, without using pointers in C. But sometimes it is getting a crash and sometimes it shows an error message about 'not enough memory'. And I don't want to use pointers in my application.

I have a local variable (inside a function) defined like this:

 double myArray[50][785190]={0}; 

I tried the code above but it's not working.

Answer 1

I thought you could do this, at least in C++, not sure if/when that was added to C.

double myArray[50][785190]={{0}}; 

But, as you said you're getting out of memory errors. Declaring 300meg on the stack is generally not a good idea. Move that to a global variable (outside of any functions) and it will no longer be on the stack. Or declare it static. In either case your code will not be reentrant with a global or static array but I'm assuming you don't need it to be for such a large array.

Otherwise you can do this to clear it as well

double myArray[50][785190]
memset(myArray, 0, sizeof(myArray));

Though any good compiler will likely generate the same code under the hood for either style.

Answer 2

If you don't want to use pointers in your 2-D array, you will need to know what size your array is ahead of time. If you declare your array as something like this:

double array[x][y];

Then to initialize it you should use a nested for loop like this (with i and j declared elsewhere):

for(i = 0; i<x; i++)  
    for(j = 0; j<y; j++)  
        array[i][j] = 0;  

I hope this helps!

EDIT- As others have pointed out, the issue is with the size, listen to them!