David , > I'm curious about how to do a symmetric LDL^T factorization (instead of > LU) with MUMPS and SuperLU. Based on this example: > > > http://www.mcs.anl.gov/petsc/petsc-3.4/src/ksp/ksp/examples/tutorials/ex52.c.html > > my understanding is as follows: > > - With MUMPS I gather that we need to specify: > > MatSetOption(A,MAT_SPD,PETSC_TRUE); > PCSetType(pc,PCCHOLESKY); > > I guess "-pc_type cholesky" on the command line is equivalent to the > PCSetType call, right? Is specifying MAT_SPD required in order for MUMPS to > do an LDL^T factorization? > Mumps supports Cholesky factorization for symmetric, and symmetric+spd matrices. You may consult mumps user manual.
> > - I gather that SuperLU doesn't provide a symmetric factorization. > SuperLU does not support Cholesky factorization. Hong
