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atof() and sscanf() do not work for me

Posted on 2002-07-09
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Last Modified: 2009-12-16
I'm trying to convert a string into a double.  I've tried both the atof() and sscanf() functions with no success.  What am I doing wrong?

I am running on a Solaris 2.8 UNIX box.

Here is the code:

#include <stdio.h>
#include <string.h>
main() {
  char numstring[] = "12.34";
  double d;
  d = atof(numstring);
  printf("String = %s\n",numstring);
  printf("Double = %f\n",d);
}

Here are the results:

String = 12.34
Double = -4264242.000000

Playing around with the format string in the second printf statement seems to change the answer, but not to 12.34.

Using sscanf() instead of atof() yields different incorrect results.

Any ideas?
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Question by:dastrw
3 Comments
 
LVL 84

Accepted Solution

by:
ozo earned 50 total points
ID: 7142542
#include <stdlib.h>
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LVL 30

Expert Comment

by:SteveGTR
ID: 7143200
You should be using the long float formater for the seconds printf:

#include <stdio.h>
#include <string.h>
main() {
 char numstring[] = "12.34";
 double d;
 d = atof(numstring);
 printf("String = %s\n",numstring);
 printf("Double = %lf\n",d);  // %f should be %lf
}

Good Luck,
Steve
0
 
LVL 2

Author Comment

by:dastrw
ID: 7143930
Thanks.  I must have zoned and thought stdio.h was the same as stdlib.h!
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