petsc-3.10.5 2019-03-28
MatDiagonalSet
Computes Y = Y + D, where D is a diagonal matrix that is represented as a vector. Or Y[i,i] = D[i] if InsertMode is INSERT_VALUES.
Synopsis
#include "petscmat.h"
PetscErrorCode MatDiagonalSet(Mat Y,Vec D,InsertMode is)
Input Parameters
Neighbor-wise Collective on Mat and Vec
Notes
If the matrix Y is missing some diagonal entries this routine can be very slow. To make it fast one should initially
fill the matrix so that all diagonal entries have a value (with a value of zero for those locations that would not have an
entry).
Keywords
matrix, add, shift, diagonal
See Also
MatShift(), MatScale(), MatDiagonalScale()
Level
intermediate
Location
src/mat/utils/axpy.c
Examples
src/ts/examples/tutorials/ex50.c.html
src/tao/pde_constrained/examples/tutorials/elliptic.c.html
Implementations
MatDiagonalSet_MPIAIJ in src/mat/impls/aij/mpi/mpiaij.c
MatDiagonalSet_SeqAIJ in src/mat/impls/aij/seq/aij.c
MatDiagonalSet_IS in src/mat/impls/is/matis.c
MatDiagonalSet_MFFD in src/mat/impls/mffd/mffd.c
MatDiagonalSet_Nest in src/mat/impls/nest/matnest.c
MatDiagonalSet_MPISELL in src/mat/impls/sell/mpi/mpisell.c
MatDiagonalSet_Shell in src/mat/impls/shell/shell.c
Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages