view Python/atof.c @ 50640:368df0060740 3.0

Blocked revisions 68417 via svnmerge ................ r68417 | tarek.ziade | 2009-01-09 01:15:45 +0100 (Fri, 09 Jan 2009) | 9 lines Merged revisions 68415 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r68415 | tarek.ziade | 2009-01-09 00:56:31 +0100 (Fri, 09 Jan 2009) | 1 line fixed #4394 make the storage of the password optional in .pypirc ........ ................
author Tarek Ziadé <ziade.tarek@gmail.com>
date Fri, 09 Jan 2009 00:17:40 +0000
parents 2dea40e40d9d
children fd25030223b0
line wrap: on
line source


/* 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;
}