petsc-3.7.3 2016-07-24
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# MATSOLVERUMFPACK

"umfpack" - A matrix type providing direct solvers (LU) for sequential matrices via the external package UMFPACK. Use ./configure --download-suitesparse to install PETSc to use UMFPACK

Use -pc_type lu -pc_factor_mat_solver_package umfpack to us this direct solver

Consult UMFPACK documentation for more information about the Control parameters which correspond to the options database keys below.

### Options Database Keys

| -mat_umfpack_ordering | - CHOLMOD, AMD, GIVEN, METIS, BEST, NONE
| -mat_umfpack_prl | - UMFPACK print level: Control[UMFPACK_PRL]
| -mat_umfpack_strategy <AUTO> | - (choose one of) AUTO UNSYMMETRIC SYMMETRIC 2BY2
| -mat_umfpack_dense_col <alpha_c> | - UMFPACK dense column threshold: Control[UMFPACK_DENSE_COL]
| -mat_umfpack_dense_row <0.2> | - Control[UMFPACK_DENSE_ROW]
| -mat_umfpack_amd_dense <10> | - Control[UMFPACK_AMD_DENSE]
| -mat_umfpack_block_size <bs> | - UMFPACK block size for BLAS-Level 3 calls: Control[UMFPACK_BLOCK_SIZE]
| -mat_umfpack_2by2_tolerance <0.01> | - Control[UMFPACK_2BY2_TOLERANCE]
| -mat_umfpack_fixq <0> | - Control[UMFPACK_FIXQ]
| -mat_umfpack_aggressive <1> | - Control[UMFPACK_AGGRESSIVE]
| -mat_umfpack_pivot_tolerance <delta> | - UMFPACK partial pivot tolerance: Control[UMFPACK_PIVOT_TOLERANCE]
| -mat_umfpack_sym_pivot_tolerance <0.001> | - Control[UMFPACK_SYM_PIVOT_TOLERANCE]
| -mat_umfpack_scale <NONE> | - (choose one of) NONE SUM MAX
| -mat_umfpack_alloc_init <delta> | - UMFPACK factorized matrix allocation modifier: Control[UMFPACK_ALLOC_INIT]
| -mat_umfpack_droptol <0> | - Control[UMFPACK_DROPTOL]
| -mat_umfpack_irstep <maxit> | - UMFPACK maximum number of iterative refinement steps: Control[UMFPACK_IRSTEP]

Note: UMFPACK is part of SuiteSparse http://faculty.cse.tamu.edu/davis/suitesparse.html

### See Also

PCLU, MATSOLVERSUPERLU, MATSOLVERMUMPS, PCFactorSetMatSolverPackage(), MatSolverPackage

Level:beginner
Location: src/mat/impls/aij/seq/umfpack/umfpack.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages