[SciPy-dev] Inclusion of cython code in scipy
Stéfan van der Walt
stefan at sun.ac.za
Wed Apr 23 13:11:10 EDT 2008
2008/4/23 Nathan Bell <wnbell at gmail.com>:
> I don't see how writing Cython is easier than writing C/C++/Fortran.
> Clearly if you only know Python, then Cython is an easier language to
> learn. However, I doubt the Cython abstraction is so complete that
> one can avoid learning C.
For one, memory management. Teaching someone to use the Python C API
properly is a pain, which is why we often revert to tools like SWIG
and Ctypes.
Look at ndimage, or the numpy core -- why do so few people dare touch
it? That code is hard to wrap your head around.
If C code has a well designed API (in other words, if it is being used
like FORTRAN), then sure -- it is easy to wrap in almost any language.
The moment you start to implement anything more advanced than bit
twiddling in pre-allocated memory, you're in for a long haul.
> Clearly I think SciPy has a long life ahead of it. At the same time,
> I spent effort ensuring that sparsetools knows absolutely nothing
> about NumPy/SciPy. IMO the utility of a stand-alone library is
> greater than a tighter coupling between sparsetools and Python. For
> instance, I can now combine the C++ I've written for PyAMG with
> sparsetools to make a lightweight algebraic multigrid code in pure
> C++.
I think you made the right decision for your specific application, but
I don't think that is necessarily the route all our packages should
take. Besides, most of the code we write is in Python, and cannot be
used in non-Python libraries anyway.
Regards
Stéfan
More information about the SciPy-Dev
mailing list