Preconditioner - LU

Usage

-pc_type lu

Options:

-pc_factor_in_place

Form LU in the same memory as the matrix

-pc_factor_fill

Expected non-zeros in LU/non-zeros in matrix. Default = 5

-pc_factor_shift_nonzero

Shift added to diagonal

-pc_factor_shift_nonzero

Shift added to diagonal. Default = 0

-pc_factor_shift_positive_definite

Manteuffel shift applied to diagonal

-pc_factor_zeropivot

Pivot is considered zero if less than ?. Default = 1e-12

-pc_factor_reuse_fill

Use fill from previous factorization

-pc_factor_reuse_ordering

Reuse ordering from previous factorization

-pc_factor_mat_ordering_type

Reordering to reduce nonzeros in LU:(one of) natural nd 1wd rcm qmd rowlength

-pc_factor_nonzeros_along_diagonal

Reorder to remove zeros from diagonal

-pc_factor_pivoting

Pivoting tolerance (used only for some factorization). Default = 1e-06

-pc_factor_pivot_in_blocks

Pivot inside matrix blocks for BAIJ and SBAIJ

Info: Often used for solving linear systems directly using -ksp_type preonly

Back to Main Page