petsc-3.8.4 2018-03-24

DMPlexSetAnchors

Set the layout of the local anchor (point-to-point) constraints. Unlike boundary conditions, when a point's degrees of freedom in a section are constrained to an outside value, the anchor constraints set a point's degrees of freedom to be a linear combination of other points' degrees of freedom.

Synopsis

#include "petscdmplex.h"   
PetscErrorCode DMPlexSetAnchors(DM dm, PetscSection anchorSection, IS anchorIS)

After specifying the layout of constraints with DMPlexSetAnchors(), one specifies the constraints by calling DMGetConstraints() and filling in the entries in the constraint matrix.

collective on dm

Input Parameters

	dm	- The DMPlex object
	anchorSection	- The section that describes the mapping from constrained points to the anchor points listed in anchorIS. Must have a local communicator (PETSC_COMM_SELF or derivative).
	anchorIS	- The list of all anchor points. Must have a local communicator (PETSC_COMM_SELF or derivative).

The reference counts of anchorSection and anchorIS are incremented.

DMPlexSetAnchors

Synopsis

Input Parameters

See Also