changeset: fsolve

[John W. Eaton]

On 31-Oct-2008, Jaroslav Hajek wrote:

| please consider the attached changeset, reimplementing fsolve as
| m-file function and removing the old fsolve code, including MINPACK.
| The advantages we get using an m-file include:
| 1. more understandable, modifiable and maintainable code (hopefully :)
| 2. reentrancy
| 3. will compute in single precision if given single precision inputs.
| 4. possibly faster for large problems, because it uses blocked QR from
| LAPACK instead of MINPACK's own implementation.

These are all reasonable advantages.

One disadvantage that I can see is that we no longer have a simple
interface to use from liboctave, or in standalone programs.  But if no
other parts of Octave other than the fsolve function were using that
anyway, then it is probably not a significant problem for us directly.
But there might be users out there who have been using the NLEqn
class, so they will be surprised when it is missing in 3.2.  I don't
know whether this is a sufficient reason to keep the old code around.
I don't think anyone ever promised that liboctave provided a stable
API.  Also, the code could probably be extracted from an old version
of Octave and used in individual applications if needed.

What happened to the doc string for fsolve?

jwe