atof reads string as 0

Question

I suppose I am just stupid (I tried all). Help me out of here:

#include <stdio.h>
#include <string.h>
int main()
{
    const char * y = "747.0";
    double x;
    x = atof(y);
    printf("%.5f\n",x);
    printf("%e\n",x);
    return 0;
}

result:

0.00000
0.000000e+00

score 6 · Accepted Answer · answered Mar 01 '14 at 21:46

6

You need to include stdlib.h to offer atof() a prototype, without proper prototype, compiler will suppose its return value be an int.

answered Mar 01 '14 at 21:46

Lee Duhem

14,695
3
29
47

that's why it's recommended to turn on all warnings – phuclv Mar 02 '14 at 09:14

score 0 · Answer 2 · answered Mar 01 '14 at 21:52

0

Try including stdlib.h because I think that is the package you need for atoi in C.

answered Mar 01 '14 at 21:52

user1497892

39
3

atof reads string as 0

2 Answers2