You might want to investigate FeasNewt from Todd Munson, which is a very elegant solution of this problem.
Matt On 10/29/07, Lisandro Dalcin <dalcinl at gmail.com> wrote: > Some time ago I made a request for adding SNESSetLinearSolve(), in > order to let users set a custom linear solve routine to SNES. I was > not clear to me if this idea was finally accepted, so I want to ask > again. > > I really needs this feature in the near future, I I would like this to > go in the next petsc release. My use case is rather simple: I'm > helping a coworker to use SNES for solving a nonlinear optimization > problem related to mesh movement (that is, move nodes retaining > element connectivities). This problem uses a regularized functional, > wich introduces a global degree of freedom coupled with all others > dofs. To avoid assembling a sparse parallel AIJ matrix with a dense > column and row, we endup needing to solve two linear systems with the > same matrix for actually solving the Hessian of the regularized > functional. > > > > -- > Lisandro Dalc?n > --------------- > Centro Internacional de M?todos Computacionales en Ingenier?a (CIMEC) > Instituto de Desarrollo Tecnol?gico para la Industria Qu?mica (INTEC) > Consejo Nacional de Investigaciones Cient?ficas y T?cnicas (CONICET) > PTLC - G?emes 3450, (3000) Santa Fe, Argentina > Tel/Fax: +54-(0)342-451.1594 > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
