[Numpy-discussion] Fortran was dead ... [was Re: rewriting NumPy code in C or C++ or similar]

[Neal Becker]

Charles R Harris wrote:

> On Tue, Mar 15, 2011 at 9:12 AM, Sturla Molden <sturla at molden.no> wrote:
> 
>> Den 14.03.2011 23:10, skrev Matthieu Brucher:
>> > - Fortran 95 has an excellent array support, which is not currently
>> > available in C/C++ (perhaps with ArBB?)
>>
>> In C++ you can actually make array libraries that behave almost like a
>> Fortran compiler (cf. Blitz++, Intel Array Building Blocks), but they
>> must be maintained to keep pace with Fortran compilers.
>>
>>
> There really isn't a satisfactory array library for C++. The fact that every
> couple of years there is another project to produce one testifies to that
> fact. And don't overlook that Fortran knows about complex numbers as well as
> arrays.
> 
> Chuck

This is partly (largely?) because different users want different things from the 
array abstraction.  I don't know if I can even start to list the differences, 
but let's try:

* 1-d, 2-d only or N-d??
* support for slice views?  What exactly kind of support?
* semantics like numpy, that make many operations avoid copy?
* what support for arithmetic operations?  Do views support arithmetic 
operations?
* expression templates?
* How's the performance with indexing?  Multi-D indexing?  How about iteration?
* What are the semantics of iterators?  I don't think I've seen 2 libs that 
treat multi-d iterators the same way (and I've tried a lot of them).