[SciPy-dev] gsl and scipy

[Pearu Peterson]

On 3 May 2002, Jochen Küpper wrote:

> On Fri, 3 May 2002 09:52:24 -0500 (CDT) pearu  wrote:
> 
> arnd> Is there the possibility to use f2py etc. to generate the
> arnd> necessary wrappers for scipy in an automatic way ?  (on the gsl
> arnd> page they recommend: swig, g-wrap) How difficult would this be ?
> >> 
> >> Pearu,  that's actually exactly the question I was going to ask for
> >> the last couple of months:)
> 
> pearu> It is rather straightforward for functions with scalar
> pearu> (int,float,double,..), *scalar, scalar[] arguments.
> 
> Well, more important, besides the "complex"-problem: What's about
> functions taking arrays or function arguments (which in general are
> some fancy struct again)?  I.e.
> ,----
> | void gsl_siman_solve (const gsl_rng * R, void *X0_P,
> |           gsl_siman_Efunc_t EF, gsl_siman_step_t TAKE_STEP,
> |           gsl_siman_metric_t DISTANCE, gsl_siman_print_t
> |           PRINT_POSITION, gsl_siman_copy_t COPYFUNC,
> |           gsl_siman_copy_construct_t COPY_CONSTRUCTOR,
> |           gsl_siman_destroy_t DESTRUCTOR, size_t ELEMENT_SIZE,
> |           gsl_siman_params_t PARAMS)
> `----

Function arguments are fine for f2py provided that they are
expected to take only scalar or array arguments.

So, let me restate what f2py can wrap:

  C/Fortran functions with scalar[+], array[++], 
      and function [*] arguments
  Global C structs [**]/Fortran COMMON blocks
  Fortran F90 module subroutines/functions
  Fortran F90 module data

[+] scalar is C char, short, int, long, float, double, {float,float},
    {double,double}
[++] array is a pointer of a scalar type, eg. *int, *double, etc.
[*] with only scalar and array arguments
[**] containing only scalars and arrays

For some "fancy" C functions it is possible to write simple interface
functions that fall into the category that f2py can wrap.

For anything else f2py is silent.

Regards,
	Pearu