petsc-3.11.4 2019-09-28

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

	Y	- the input matrix
	D	- the diagonal matrix, represented as a vector
	i	- INSERT_VALUES or ADD_VALUES

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

Level

intermediate

MatDiagonalSet

Synopsis

Input Parameters

Notes

Keywords

See Also

Level

Location

Examples

Implementations