Mercurial > cpython-lru_cache-weakref
annotate Python/fmod.c @ 19051:f20727cc3d0f legacy-trunk
Implement PEP 238 in its (almost) full glory.
This introduces:
- A new operator // that means floor division (the kind of division
where 1/2 is 0).
- The "future division" statement ("from __future__ import division)
which changes the meaning of the / operator to implement "true
division" (where 1/2 is 0.5).
- New overloadable operators __truediv__ and __floordiv__.
- New slots in the PyNumberMethods struct for true and floor division,
new abstract APIs for them, new opcodes, and so on.
I emphasize that without the future division statement, the semantics
of / will remain unchanged until Python 3.0.
Not yet implemented are warnings (default off) when / is used with int
or long arguments.
This has been on display since 7/31 as SF patch #443474.
Flames to /dev/null.
| author | Guido van Rossum <guido@python.org> |
|---|---|
| date | Wed, 08 Aug 2001 05:00:18 +0000 |
| parents | 2dea40e40d9d |
| children |
| rev | line source |
|---|---|
| 145 | 1 |
| 6 | 2 /* Portable fmod(x, y) implementation for systems that don't have it */ |
| 3 | |
|
18835
2dea40e40d9d
Patch #411138: Rename config.h to pyconfig.h. Closes bug #231774.
Martin v. Löwis <martin@v.loewis.de>
parents:
14375
diff
changeset
|
4 #include "pyconfig.h" |
| 2434 | 5 |
|
13761
59f8cedcf049
merge Include/my*.h into Include/pyport.h
Peter Schneider-Kamp <nowonder@nowonder.de>
parents:
13256
diff
changeset
|
6 #include "pyport.h" |
| 6 | 7 #include <errno.h> |
| 8 | |
| 9 double | |
| 2434 | 10 fmod(double x, double y) |
| 6 | 11 { |
| 12 double i, f; | |
| 13 | |
| 14 if (y == 0.0) { | |
| 15 errno = EDOM; | |
| 16 return 0.0; | |
| 17 } | |
| 18 | |
| 19 /* return f such that x = i*y + f for some integer i | |
| 20 such that |f| < |y| and f has the same sign as x */ | |
| 21 | |
| 22 i = floor(x/y); | |
| 23 f = x - i*y; | |
| 24 if ((x < 0.0) != (y < 0.0)) | |
| 25 f = f-y; | |
| 26 return f; | |
| 27 } |