GSL, FFI, GCL, Windows; was: find_root with bfloats

On Wed, Sep 29, 2010 at 11:56 AM, Kostas Oikonomou <ko at research.att.com> wrote:

> I agree that the ideal is a library that fits the computer algebra way of
> doing things, sometimes symbolic, sometimes numeric. ?The GSL is purely
> numeric, as far as I know. ?But maxima is missing a lot of numerical
> capabilities: optimization is the one that is prominent for me right now, I
> have to do it in Mathematica and move the results to maxima. ?I was
> encouraged by the ease by which Ray converted find_root to use bigfloats,
> and thought something similar might be doable with the GSL and its Common
> Lisp interface.

Whatever the merits of GSL, it certainly cannot make use of Maxima
bigfloats. GSL can provide Maxima with functions that compute with
ordinary floats, but that's it.

The Lisp interface for GSL is almost certainly (I didn't look at it)
just a glue layer that translates Lisp function calls to C and
converts Lisp objects to/from C; almost certainly it is not an
implementation of the GSL functions in C, which would be
susceptible to bigfloatification as with find_root.

It is conceivable that GSL could be reworked to make use of
generic arithmetic, in which case it could use Maxima bigfloats
or other Maxima-specific numeric types. I wouldn't be surprised
if it has been suggested before.

best

Robert Dodier