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| 1 | + | |
| 2 | +/* Just in case you haven't got an atof() around... | |
| 3 | + This one doesn't check for bad syntax or overflow, | |
| 4 | + and is slow and inaccurate. | |
| 5 | + But it's good enough for the occasional string literal... */ | |
| 6 | + | |
| 7 | +#include "pyconfig.h" | |
| 8 | + | |
| 9 | +#include <ctype.h> | |
| 10 | + | |
| 11 | +double atof(char *s) | |
| 12 | +{ | |
| 13 | + double a = 0.0; | |
| 14 | + int e = 0; | |
| 15 | + int c; | |
| 16 | + while ((c = *s++) != '\0' && isdigit(c)) { | |
| 17 | + a = a*10.0 + (c - '0'); | |
| 18 | + } | |
| 19 | + if (c == '.') { | |
| 20 | + while ((c = *s++) != '\0' && isdigit(c)) { | |
| 21 | + a = a*10.0 + (c - '0'); | |
| 22 | + e = e-1; | |
| 23 | + } | |
| 24 | + } | |
| 25 | + if (c == 'e' || c == 'E') { | |
| 26 | + int sign = 1; | |
| 27 | + int i = 0; | |
| 28 | + c = *s++; | |
| 29 | + if (c == '+') | |
| 30 | + c = *s++; | |
| 31 | + else if (c == '-') { | |
| 32 | + c = *s++; | |
| 33 | + sign = -1; | |
| 34 | + } | |
| 35 | + while (isdigit(c)) { | |
| 36 | + i = i*10 + (c - '0'); | |
| 37 | + c = *s++; | |
| 38 | + } | |
| 39 | + e += i*sign; | |
| 40 | + } | |
| 41 | + while (e > 0) { | |
| 42 | + a *= 10.0; | |
| 43 | + e--; | |
| 44 | + } | |
| 45 | + while (e < 0) { | |
| 46 | + a *= 0.1; | |
| 47 | + e++; | |
| 48 | + } | |
| 49 | + return a; | |
| 50 | +} | |