Mercurial > cpython-lru_cache-weakref
view Python/atof.c @ 22200:dab05ab0347b legacy-trunk
Docstring for filter(): Someone on the Tutor list reasonably complained
that it didn't tell enough of the truth.
Bugfix candidate (I guess -- it helps and it's harmless).
| author | Tim Peters <tim.peters@gmail.com> |
|---|---|
| date | Sat, 09 Mar 2002 00:06:26 +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; }
