MatDiagonalGetDiagonal#
Get the diagonal of a MATDIAGONAL
Synopsis#
#include "petscmat.h"
PetscErrorCode MatDiagonalGetDiagonal(Mat A, Vec *diag)
Input Parameter#
A - the
MATDIAGONAL
Output Parameter#
diag - the
Vec
that defines the diagonal
Note#
The user must call
MatDiagonalRestoreDiagonal()
before using the matrix again.
For a copy of the diagonal values, rather than a reference, use MatGetDiagonal()
Any changes to the obtained vector immediately change the action of the Mat
. The matrix can be changed more efficiently by accessing this vector and changing its values, instead of filling a work vector and using MatDiagonalSet()
See Also#
Matrices, MATDIAGONAL
, MatCreateDiagonal()
, MatDiagonalRestoreDiagonal()
, MatDiagonalGetInverseDiagonal()
, MatGetDiagonal()
Level#
developer
Location#
Implementations#
MatDiagonalGetDiagonal_Diagonal() in src/mat/impls/diagonal/diagonal.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages