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v0.8.1
https://github.com/python/cpython
09 December 2020, 11:06:31 UTC
Revision c707893f9cee870bba8364b3a06eb9cfa3b80e58 authored by Benjamin Peterson on 26 August 2017, 18:18:30 UTC, committed by Benjamin Peterson on 26 August 2017, 18:18:30 UTC 
version bumps for 2.7.14rc1
1 parent 48455e2
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Tip revision: c707893f9cee870bba8364b3a06eb9cfa3b80e58 authored by Benjamin Peterson on 26 August 2017, 18:18:30 UTC
version bumps for 2.7.14rc1
Tip revision: c707893
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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