names in multimin section

Brian Gough bjg@network-theory.co.uk
Thu Mar 2 19:20:00 GMT 2006


Ivo Alxneit-Kamber writes:
 > i tend to agree here (see my previous post on the modified
 > initialization of nm_simplex), but i think we might get along using ONLY
 > gsl_multimin_function_fdf i.e. only one type of function. if a minimizer
 > does not use gradients you could set void * df and void * fdf to a NULL
 > pointer (or leave it, it is never been used). currently only nm_simplex
 > falls into the latter category (i do not know of any other algorithm
 > that does not make use of derivatives, but we should check before we
 > make any changes here to make sure it will not break in the future).
 > with this change the interface would be simpler.

It should be simple enough to switch between an fdfminizer and
fminimizer function by copying the three elements of the struct.

While it's true that odeinitval doesn't distinguish between the two
cases of with/without jacobian, it's an exception to the main scheme
in the design document ("Minimal Structs").  

Passing a null value for the jacobian is a just suggested as trick
that happens to work, not really part of the design.

-- 
Brian Gough



More information about the Gsl-discuss mailing list