Mercurial > cpython-lru_cache-weakref
view Python/atof.c @ 17581:c1937faabb23 2.1
Added support for optional explanation parameter to the \versionadded
macro.
Refactored do_cmd_versionadded() and do_cmd_versionchanged() to do most
of the work in a helper function, with the do_cmd_*() wrappers just supplying
a portion of the replacement text.
| author | Fred Drake <fdrake@acm.org> |
|---|---|
| date | Wed, 18 Apr 2001 17:29:14 +0000 |
| parents | 6f6f965c5e2d |
| children | 2dea40e40d9d |
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/* 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 "config.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; }
