petscmain 20210420
MatILUFactorSymbolic
Performs symbolic ILU factorization of a matrix. Uses levels of fill only, not drop tolerance. Use MatLUFactorNumeric() to complete the factorization.
Synopsis
#include "petscmat.h"
PetscErrorCode MatILUFactorSymbolic(Mat fact,Mat mat,IS row,IS col,const MatFactorInfo *info)
Collective on Mat
Input Parameters
 mat   the matrix

 row   row permutation

 column   column permutation

 info   structure containing

levels  number of levels of fill.
expected fill  as ratio of original fill.
1 or 0  indicating force fill on diagonal (improves robustness for matrices
missing diagonal entries)
Output Parameters
 fact   new matrix that has been symbolically factored

Notes
See UsersManual: ch_mat for additional information about choosing the fill factor for better efficiency.
Most users should employ the simplified KSP interface for linear solvers
instead of working directly with matrix algebra routines such as this.
See, e.g., KSPCreate().
See Also
MatLUFactorSymbolic(), MatLUFactorNumeric(), MatCholeskyFactor()
MatGetOrdering(), MatFactorInfo
Note: this uses the definition of level of fill as in Y. Saad, 2003
Developer Note: fortran interface is not autogenerated as the f90
interface defintion cannot be generated correctly [due to MatFactorInfo]
References
Y. Saad, Iterative methods for sparse linear systems Philadelphia: Society for Industrial and Applied Mathematics, 2003
Level
developer
Location
src/mat/interface/matrix.c
Implementations
MatILUFactorSymbolic_SeqAIJ in src/mat/impls/aij/seq/aijfact.c
MatILUFactorSymbolic_SeqAIJCUSPARSE in src/mat/impls/aij/seq/seqcusparse/aijcusparse.cu
MatILUFactorSymbolic_SeqBAIJ in src/mat/impls/baij/seq/baijfact2.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages