3.1 status report

[David Bateman]

Jaroslav Hajek wrote:

> I see, however, a couple drawbacks:
> 1. most of GSL uses hard-coded double as the real type. Now that we
> have true single precision, this is really a big drawback. I don't
> reckon there are plans to change this state in GSL. And I can't see
> any good way out of this.
> 2. the "core" linear algebra operation of the MINPACK algorithms
> (trust-region Levenberg-Marquardt and Powell's hybrid method) is the
> QRP factorization. GSL has its own QRP code (as well as other linear
> algebra codes) and employs it here. I think, however, that LAPACK is
> fairly better.

To me these are both good reasons not to use GSL. What I thought we were
gaining with GSL was

* upto date and maintained code
* code that generally performed better
* code that returned valid results for a wider range of input values.

Though given the two points above I'm not sure GSL is worth it.

D.