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v0.8.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision 6cc7940e10372aa696ac62d9ab00bf0717a94ae6 authored by Barry Warsaw on 08 May 2008, 13:16:19 UTC, committed by Barry Warsaw on 08 May 2008, 13:16:19 UTC 
Bump to 2.6a3
1 parent c27b8b8
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Tip revision: 6cc7940e10372aa696ac62d9ab00bf0717a94ae6 authored by Barry Warsaw on 08 May 2008, 13:16:19 UTC
Bump to 2.6a3
Tip revision: 6cc7940
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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