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v0.5.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision f34bef2378460cacf97e8574148f5d5168f26bc8 authored by Eric Smith on 25 February 2010, 14:16:46 UTC, committed by Eric Smith on 25 February 2010, 14:16:46 UTC 
Merged revisions 78440 via svnmerge from
 
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r78440 | eric.smith | 2010-02-25 09:14:35 -0500 (Thu, 25 Feb 2010) | 1 line

  Issue #5965: Add documentation for parts of format specification language.
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Tip revision: f34bef2378460cacf97e8574148f5d5168f26bc8 authored by Eric Smith on 25 February 2010, 14:16:46 UTC
Merged revisions 78440 via svnmerge from
Tip revision: f34bef2
atof.c 

/* Just in case you haven't got an atof() around...
   This one doesn't check for bad syntax or overflow,
   and is slow and inaccurate.
   But it's good enough for the occasional string literal... */

#include "pyconfig.h"

#include <ctype.h>

double atof(char *s)
{
	double a = 0.0;
	int e = 0;
	int c;
	while ((c = *s++) != '\0' && isdigit(c)) {
		a = a*10.0 + (c - '0');
	}
	if (c == '.') {
		while ((c = *s++) != '\0' && isdigit(c)) {
			a = a*10.0 + (c - '0');
			e = e-1;
		}
	}
	if (c == 'e' || c == 'E') {
		int sign = 1;
		int i = 0;
		c = *s++;
		if (c == '+')
			c = *s++;
		else if (c == '-') {
			c = *s++;
			sign = -1;
		}
		while (isdigit(c)) {
			i = i*10 + (c - '0');
			c = *s++;
		}
		e += i*sign;
	}
	while (e > 0) {
		a *= 10.0;
		e--;
	}
	while (e < 0) {
		a *= 0.1;
		e++;
	}
	return a;
}
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