Atof() - C library function Program

Declaration :

double atof(const char *str)

1	double atof(const char *str)

Explanation :

Purpose	The C library function *double atof(const char str) converts the string argument str** to a floating-point number (type double).
Parameters	str ===> This is the string having the representation of a floating-point number.
Return Value	This function returns the converted floating point number as a double value. If no valid conversion could be performed it returns zero (0.0).
Exception

C Program : Example

The following example shows the usage of atof() function.

<span style='color:#004a43; '>#</span><span style='color:#004a43; '>include </span><span style='color:#800000; '><</span><span style='color:#40015a; '>stdio.h</span><span style='color:#800000; '>></span>
<span style='color:#004a43; '>#</span><span style='color:#004a43; '>include </span><span style='color:#800000; '><</span><span style='color:#40015a; '>stdlib.h</span><span style='color:#800000; '>></span>
<span style='color:#004a43; '>#</span><span style='color:#004a43; '>include </span><span style='color:#800000; '><</span><span style='color:#40015a; '>string.h</span><span style='color:#800000; '>></span>
<span style='color:#200080; font-weight:bold; '>int</span> <span style='color:#400000; '>main</span><span style='color:#308080; '>(</span><span style='color:#308080; '>)</span>
<span style='color:#406080; '>{</span>
   <span style='color:#200080; font-weight:bold; '>float</span> value<span style='color:#406080; '>;</span>
   <span style='color:#200080; font-weight:bold; '>char</span> str<span style='color:#308080; '>[</span><span style='color:#008c00; '>20</span><span style='color:#308080; '>]</span><span style='color:#406080; '>;</span>
   <span style='color:#003060; '>strcpy</span><span style='color:#308080; '>(</span>str<span style='color:#308080; '>,</span> <span style='color:#800000; '>"</span><span style='color:#1060b6; '>12.34</span><span style='color:#800000; '>"</span><span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   value<span style='color:#308080; '>=</span> <span style='color:#003060; '>atof</span><span style='color:#308080; '>(</span>str<span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   <span style='color:#003060; '>printf</span><span style='color:#308080; '>(</span><span style='color:#800000; '>"</span><span style='color:#0f69ff; '>n</span><span style='color:#1060b6; '>String equivalent value of </span><span style='color:#0f69ff; '>%s</span><span style='color:#1060b6; '> = </span><span style='color:#0f69ff; '>%f</span><span style='color:#800000; '>"</span><span style='color:#308080; '>,</span> str<span style='color:#308080; '>,</span> value<span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   <span style='color:#003060; '>strcpy</span><span style='color:#308080; '>(</span>str<span style='color:#308080; '>,</span> <span style='color:#800000; '>"</span><span style='color:#1060b6; '>pritesh</span><span style='color:#800000; '>"</span><span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   value<span style='color:#308080; '>=</span> <span style='color:#003060; '>atoi</span><span style='color:#308080; '>(</span>str<span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   <span style='color:#003060; '>printf</span><span style='color:#308080; '>(</span><span style='color:#800000; '>"</span><span style='color:#0f69ff; '>n</span><span style='color:#1060b6; '>String equivalent value of </span><span style='color:#0f69ff; '>%s</span><span style='color:#1060b6; '> = </span><span style='color:#0f69ff; '>%f</span><span style='color:#800000; '>"</span><span style='color:#308080; '>,</span> str<span style='color:#308080; '>,</span> value<span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
   <span style='color:#200080; font-weight:bold; '>return</span><span style='color:#308080; '>(</span><span style='color:#008c00; '>0</span><span style='color:#308080; '>)</span><span style='color:#406080; '>;</span>
<span style='color:#406080; '>}</span>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

int main()

{

float value;

char str[20];

strcpy(str, "12.34");

value= atof(str);

printf("nString equivalent value of %s = %f", str, value);

strcpy(str, "pritesh");

value= atoi(str);

return(0);

}

Table of Content

Atof() - C library function Program

Declaration :

Explanation :

C Program : Example