petsc-3.12.5 2020-03-29

DMStagVecSetValuesStencil

Set Vec values using global grid indexing

Synopsis

PetscErrorCode DMStagVecSetValuesStencil(DM dm,Vec vec,PetscInt n,const DMStagStencil *pos,const PetscScalar *val,InsertMode insertMode)

Not Collective

Input Parameters

	dm	- the DMStag object
	vec	- the Vec
	n	- the number of values to set
	pos	- the locations to set values, as an array of DMStagStencil structs
	val	- the values to set
	insertMode	- INSERT_VALUES or ADD_VALUES

Notes

The vector is expected to be a global vector compatible with the DM (usually obtained by DMGetGlobalVector() or DMCreateGlobalVector()).

This approach is not as efficient as setting values directly with DMStagVecGetArrayDOF(), which is recommended for matrix-free operators. For assembling systems, where overhead may be less important than convenience, this routine could be helpful in assembling a righthand side and a matrix (using DMStagMatSetValuesStencil()).

Level

advanced

Location