DMNetworkGetLocalVecOffset#

Get the offset for accessing the variables associated with a component at the given vertex/edge from the local vector

Synopsis#

#include "petscdmnetwork.h"  
PetscErrorCode DMNetworkGetLocalVecOffset(DM dm, PetscInt p, PetscInt compnum, PetscInt *offset)

Not Collective

Input Parameters#

dm - the DMNETWORK object
p - the edge or vertex point
compnum - component number; use ALL_COMPONENTS if no specific component is requested

Output Parameter#

offset - the local offset

Notes#

These offsets can be passed to MatSetValuesLocal() for matrices obtained with DMCreateMatrix().

For vectors obtained with DMCreateLocalVector() the offsets can be used with VecSetValues().

For vectors obtained with DMCreateLocalVector() and the array obtained with VecGetArray(vec,&array) you can access or set the vector values with array[offset].

For vectors obtained with DMCreateGlobalVector() the offsets can be used with VecSetValuesLocal().