MatSetValue#

Set a single entry into a matrix. This value may be cached, so MatAssemblyBegin() and MatAssemblyEnd() MUST be called after all calls to MatSetValue() have been completed.

Synopsis#

#include <petscmat.h>
PetscErrorCode MatSetValue(Mat m,PetscInt i,PetscInt j,PetscScalar va,InsertMode mode)

Not Collective

Input Parameters#

  • m - the matrix

  • i - the row location of the entry

  • j - the column location of the entry

  • va - the value to insert

  • mode - either INSERT_VALUES or ADD_VALUES

Note#

For efficiency one should use MatSetValues() and set several values simultaneously.

See Also#

Matrices, Mat, MatAssemblyBegin(), MatAssemblyEnd, InsertMode, MatGetValue(), MatSetValues(), MatSetValueLocal(), MatSetValuesLocal()

Level#

beginner

Location#

include/petscmat.h

Examples#

src/ksp/ksp/tutorials/ex21.c
src/ksp/ksp/tutorials/ex27.c
src/ksp/ksp/tutorials/ex4.c
src/ksp/ksp/tutorials/ex44f.F90
src/ksp/ksp/tutorials/ex59.c
src/ksp/ksp/tutorials/ex61f.F90
src/ksp/ksp/tutorials/ex73.c
src/ksp/ksp/tutorials/ex76.c
src/mat/tutorials/ex4.c
src/mat/tutorials/ex4f.F90
src/snes/tutorials/ex47cu.cu

Edit on GitLab

Index of all Mat routines
Table of Contents for all manual pages
Index of all manual pages