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v0.8.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision 07a4a3851d29eb117508dd292ee347db33b50a1a authored by Barry Warsaw on 21 August 2008, 01:15:08 UTC, committed by Barry Warsaw on 21 August 2008, 01:15:08 UTC 
Bump to 2.6b3.
1 parent cd3b74d
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Tip revision: 07a4a3851d29eb117508dd292ee347db33b50a1a authored by Barry Warsaw on 21 August 2008, 01:15:08 UTC
Bump to 2.6b3.
Tip revision: 07a4a38
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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