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chuck87	3 Jul, 2008 - 01:18 PM Post #1
D.I.C Head Joined: 7 Sep, 2007 Posts: 65 My Contributions	I am trying to dynamically allocate memory for a 2D-array. The output shows that the array contains only zeros which is my problem.Here is the code CODE #include <stdio.h> #include <stdlib.h> int main(void) { int i,j,n=6; double *array; array=malloc(n sizeof(double )); for(i=0; i<n; i++) { array[i]=malloc( n sizeof(double *)); } for(i=0; i<n; i++){ for(j=0; j<n; j++){ array[i][j]=0.2; printf("%d\t",array[i][j]); } } return 0; }
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Cerolobo	3 Jul, 2008 - 01:26 PM Post #2
D.I.C Regular Joined: 5 Apr, 2008 Posts: 440 Thanked 30 times My Contributions	You've got two issues Issue Number 1: CODE for(i=0; i<n; i++) { array[i]=malloc( n * sizeof(double )); } In the above code, you are allocating n sizeof(double ) bytes. Assuming 32 bit CPU, sizeof(double ) is 4 bytes. What you wanted is sizeof(double), which is 8 bytes, since you are allocating doubles and not double pointers. Issue Number 2: CODE printf("%d\t",array[i][j]); %d is used to print out integers, not doubles. What you want is %f. %f actually prints out doubles.
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