When trying to figure out why some of my optimizations were failing, I
wrapped a number of optimizers available in GSL so they can be used in
IMP. These include another implementation of CG, a quasi-newton
optimizer and simplex (I mostly wanted CG, but the other came for free).
We can't ship the wrappers (unless we want to ship a GPL-ed special
edition of IMP along with the LGPL one), but they might be useful to
people to experiment with. If others are interested, I'll add a
salilab_modules directory in IMP for such in-house code which would not
be released (we can figure out how to make it inaccessible to the
outside world when such is needed).