MatLUFactor#

Performs in-place LU factorization of matrix.

Synopsis#

#include "petscmat.h" 
PetscErrorCode MatLUFactor(Mat mat, IS row, IS col, const MatFactorInfo *info)

Collective

Input Parameters#

mat - the matrix
row - row permutation
col - column permutation
info - options for factorization, includes

          fill - expected fill as ratio of original fill.
          dtcol - pivot tolerance (0 no pivot, 1 full column pivoting)
                   Run with the option -info to determine an optimal value to use

Notes#

Most users should employ the KSP interface for linear solvers instead of working directly with matrix algebra routines such as this. See, e.g., KSPCreate().

This changes the state of the matrix to a factored matrix; it cannot be used for example with MatSetValues() unless one first calls MatSetUnfactored().

This is really in-place only for dense matrices, the preferred approach is to use MatGetFactor(), MatLUFactorSymbolic(), and MatLUFactorNumeric() when not using KSP.