Differences between revisions 10 and 11
 ⇤ ← Revision 10 as of 2006-12-09 07:08:45 → Size: 1701 Editor: ChrisBurke Comment: ← Revision 11 as of 2008-12-08 10:45:40 → ⇥ Size: 1705 Editor: anonymous Comment: converted to 1.6 markup Deletions are marked like this. Additions are marked like this. Line 42: Line 42: attachment:lbfgs.zip [[attachment:lbfgs.zip]]

This script calls LBFGS Subroutine converted from Fortran to C. Install the files in the Addon directory and load the script lbfgs.ijs. You can test the subroutine by running:

,.lbfgs_test ''

Notes from the Fortran Subroutine:

{{{ LIMITED MEMORY BFGS METHOD FOR LARGE SCALE OPTIMIZATION

• JORGE NOCEDAL
• ** July 1990 ***
• This subroutine solves the unconstrained minimization problem
• min F(x), x= (x1,x2,...,xN),
using the limited memory BFGS method. The routine is especially effective on problems involving a large number of variables. In a typical iteration of this method an approximation Hk to the inverse of the Hessian is obtained by applying M BFGS updates to a diagonal matrix Hk0, using information from the previous M steps. The user specifies the number M, which determines the amount of storage required by the routine. The user may also provide the diagonal matrices Hk0 if not satisfied with the default choice. The algorithm is described in "On the limited memory BFGS method for large scale optimization", by D. Liu and J. Nocedal, Mathematical Programming B 45 (1989) 503-528. }}}

There is also the script lbfgsb.ijs. It can be tested by running:

,.lbfgsb_test ''

{{{L-BFGS-B is a code for solving large nonlinear optimization problems with simple bounds on the variables.

The code can also be used for unconstrained problems and is as efficient for these problems as the earlier limited memory code L-BFGS.}}}

Trash/Packages/LBFGS (last edited 2008-12-08 10:45:40 by anonymous)