DMLocalToGlobal

updates global vectors from local vectors

Synopsis

#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMLocalToGlobal(DM dm, Vec l, InsertMode mode, Vec g)

Neighbor-wise Collective

Input Parameters

• dm - the DM object

• l - the local vector

• mode - if INSERT_VALUES then no parallel communication is used, if ADD_VALUES then all ghost points from the same base point accumulate into that base point.

• g - the global vector

Notes

The communication involved in this update can be overlapped with computation by using DMLocalToGlobalBegin() and DMLocalToGlobalEnd().

In the ADD_VALUES case you normally would zero the receiving vector before beginning this operation.

INSERT_VALUES is not supported for DMDA; in that case simply compute the values directly into a global vector instead of a local one.

Use DMLocalToGlobalHookAdd() to add additional operations that are performed on the data during the update process

See Also

DM Basics, DM, DMLocalToGlobalBegin(), DMLocalToGlobalEnd(), DMCoarsen(), DMDestroy(), DMView(), DMCreateGlobalVector(), DMCreateInterpolation(), DMGlobalToLocal(), DMGlobalToLocalEnd(), DMGlobalToLocalBegin(), DMLocalToGlobalHookAdd(), DMGlobaToLocallHookAdd()

Level

beginner

Location

src/dm/interface/dm.c

Examples

src/dm/impls/stag/tutorials/ex4.c
src/dm/impls/stag/tutorials/ex6.c
src/dm/tutorials/ex2.c
src/dm/impls/stag/tutorials/ex3.c
src/snes/tutorials/ex11.c
src/dm/impls/stag/tutorials/ex1.c
src/snes/tutorials/ex16.c
src/dm/impls/stag/tutorials/ex2.c

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Index of all DM routines
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Index of all manual pages