On Mon, May 4, 2015 at 2:11 PM, Reza Yaghmaie <[email protected]> wrote:
> > Dear PETSC representatives, > > I am solving a nonlinear problem with SNESNGMRES and it converges faster > with less iterations compared to otehr SNES methods. Any idea why that is > the case? > It is impossible to tell with this information. > Also SNESQN diverges quickly. I tried to use SNESLINESEARCHBASIC for the > linesearch option and nothing changes. > This can happen, especially if your matrix is far from the identity. > I presume it is using the default SNESQN method. Btw, there are three > options for QN, as "SNES_QN_LBFGS, SNES_QN_BROYDEN, SNES_QN_BADBROYEN" in > teh manual. I tried to associate them with SNES however it seems these > hyphened names don't work there. What am I missing? > -snes_qn_scale_type <lbfgs,broyden,badbroyden> from http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/SNES/SNESQNSetType.html Thanks, Matt Best regards, > Ray > -- 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
