[SciPy-dev] Re: Slicot library and scipy

[Nils Wagner]

On Tue, 28 Sep 2004 10:52:17 -0600
  Travis Oliphant <oliphant at ee.byu.edu> wrote:
>Nils Wagner wrote:
>
>>Dear Travis,
>>
>>As you encouraged me to learn f2py I would like to ask 
>>you,
>>if you can help me with an interface for continuous and 
>>discrete Lyapunov
>>equations as a starting point.  Once I know how to manage 
>>it in general,
>>I would be glad to submit more slicot routines to scipy.
>
>
>It looks like your problems are related to making sure 
>SB03MD has the libraries it needs to run.   It looks like 
>it needs a dummy SELECT function for DGEES (it actually 
>never calls it but the interface requires it).
>
>You also need to be sure that SB03MY and SB03MX and 
>MB01RD are compiled and linked along with SB03MD (it 
>calls them). 
>I'm attaching a modified .pyf file that you could use and 
>a util.f file with the SELECT function defined. 
>You need to compile like this (assuming you have a 
>libslicot.a placed in <path-to-slicot>)
>
>f2py -L<path-to-slicot> -lslicot -L<path-to-atlas> 
>-llapack -lf77blas -latlas  -c slicot.pyf utils.f
>
>This is the better way to do it and will allow you to 
>grow slicot.pyf until you've made available all of the 
>routines. 
>You can start the process of wrapping all of the slicot 
>library by letting f2py construct the basic .pyf file by 
>going to the slicot src directory and doing
>
>f2py -h slicot.pyf -m slicot *.f
>
>This will give you a basic, raw interface to all of the 
>slicot routines.  You will then want to edit the 
>slicot.pyf file (like I did here for sb03md) to make the 
>routine more useful --- hide some variables, show that 
>some are input and some are output variables --- and so 
>forth.
>
>You will find along the way that f2py will fail to parse 
>some of the SLICOT fortran routines.  Just don't include 
>them in the list of routines to make an interface for.  I 
>needed to move IB03AD.f  and IB03BD.f out of the way 
>before running the command to get it to complete.   The 
>resulting slicot.pyf file is huge and contains a very raw 
>interface to the entire slicot library (minus those two 
>routines --- I'm submitting a bug report to Pearu now). 
>The slicot.pyf file can be compiled with f2py as before. 
> If you want to write a setup.py file you can (but that 
>is another story).
>
>
>>
>>I am quite sure that many scipy users are interested in 
>>features 
>>provided by
>>the slicot library.
>>
>>What do you think ?
>>
>
>SLICOT would be a nice addition to SciPy.
>
>But...
>
>I noticed that the SLICOT folks don't want people 
>distributing SLICOT with their library, so it looks like 
>only the interface could be distributed with SciPy and 
>you would have to go and download the SLICOT tools from 
>them, which is too bad unless some kind of agreement and 
>separate license for SciPy could be obtained --- it looks 
>like they mainly want credit, so in SciPy we could put in 
>the help for the tools that if you use them you must 
>credit them in a paper.
>
>At any rate, perhaps the interface could be distributed 
>and then a check made at compile time (by default off) to 
>see if the library is already there then the interface 
>could be built. 
>-Travis
>
>
>
>>I look forward to heraring from you.
>>
>>Cheers,
>>                  Nils

Travis,

Thank you very much for your detailed hints !
I will ask the developers of slicot for a possible
integration of slicot in scipy and get back to
you as soon as possible.

Cheers,

              Nils

>>
>>
>>
>

Dr.-Ing. Nils Wagner

Universität Stuttgart
Institut A für Mechanik

Pfaffenwaldring 9
D-70550 Stuttgart

Phone: +49 (0)711 685 6262
Fax:   +49 (0)711 685 6282

E-mail: nwagner at mecha.uni-stuttgart.de