Mercurial > cpython-lru_cache-weakref
view Python/atof.c @ 19283:b865cd5c1925 legacy-trunk
Added comments before recently added/assigned slots in the type object,
so the backward compatibility issues will be easier to understand. I only
added comments indicating additions and assignments back to Python 2.0.
| author | Fred Drake <fdrake@acm.org> |
|---|---|
| date | Wed, 15 Aug 2001 18:32:33 +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; }
