MatGetInfo#
Returns information about matrix storage (number of nonzeros, memory, etc.).
Synopsis#
#include "petscmat.h"
PetscErrorCode MatGetInfo(Mat mat, MatInfoType flag, MatInfo *info)
Collective if MAT_GLOBAL_MAX
or MAT_GLOBAL_SUM
is used as the flag
Input Parameters#
mat - the matrix
flag - flag indicating the type of parameters to be returned (
MAT_LOCAL
- local matrix,MAT_GLOBAL_MAX
- maximum over all processors,MAT_GLOBAL_SUM
- sum over all processors)
Output Parameters#
info - matrix information context
Notes#
The MatInfo
context contains a variety of matrix data, including
number of nonzeros allocated and used, number of mallocs during
matrix assembly, etc. Additional information for factored matrices
is provided (such as the fill ratio, number of mallocs during
factorization, etc.). Much of this info is printed to PETSC_STDOUT
when using the runtime options
-info -mat_view ::ascii_info
Example for C/C++ Users#
See the file ${PETSC_DIR}/include/petscmat.h for a complete list of data within the MatInfo context. For example,
MatInfo info;
Mat A;
double mal, nz_a, nz_u;
MatGetInfo(A,MAT_LOCAL,&info);
mal = info.mallocs;
nz_a = info.nz_allocated;
Example for Fortran Users#
Fortran users should declare info as a double precision
array of dimension MAT_INFO_SIZE
, and then extract the parameters
of interest. See the file ${PETSC_DIR}/include/petsc/finclude/petscmat.h
a complete list of parameter names.
double precision info(MAT_INFO_SIZE)
double precision mal, nz_a
Mat A
integer ierr
call MatGetInfo(A,MAT_LOCAL,info,ierr)
mal = info(MAT_INFO_MALLOCS)
nz_a = info(MAT_INFO_NZ_ALLOCATED)
Developer Note#
Fortran interface is not autogenerated as the interface definition cannot be generated correctly [due to MatInfo]
See Also#
Level#
intermediate
Location#
Examples#
Implementations#
MatGetInfo_MPIAIJ in src/mat/impls/aij/mpi/mpiaij.c
MatGetInfo_MUMPS in src/mat/impls/aij/mpi/mumps/mumps.c
MatGetInfo_PaStiX in src/mat/impls/aij/mpi/pastix/pastix.c
MatGetInfo_SeqAIJ in src/mat/impls/aij/seq/aij.c
MatGetInfo_MPIBAIJ in src/mat/impls/baij/mpi/mpibaij.c
MatGetInfo_SeqBAIJ in src/mat/impls/baij/seq/baij2.c
MatGetInfo_ConstantDiagonal in src/mat/impls/cdiagonal/cdiagonal.c
MatGetInfo_MPIDense in src/mat/impls/dense/mpi/mpidense.c
MatGetInfo_SeqDense in src/mat/impls/dense/seq/dense.c
MatGetInfo_Elemental in src/mat/impls/elemental/matelem.cxx
MatGetInfo_IS in src/mat/impls/is/matis.c
MatGetInfo_MPISBAIJ in src/mat/impls/sbaij/mpi/mpisbaij.c
MatGetInfo_CHOLMOD in src/mat/impls/sbaij/seq/cholmod/sbaijcholmod.c
MatGetInfo_SeqSBAIJ in src/mat/impls/sbaij/seq/sbaij2.c
MatGetInfo_ScaLAPACK in src/mat/impls/scalapack/matscalapack.c
MatGetInfo_MPISELL in src/mat/impls/sell/mpi/mpisell.c
MatGetInfo_SeqSELL in src/mat/impls/sell/seq/sell.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages