PETSc version 3.16.6
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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 on dm

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.

See Also

DMLocalToGlobalBegin(), DMLocalToGlobalEnd(), DMCoarsen(), DMDestroy(), DMView(), DMCreateGlobalVector(), DMCreateInterpolation(), DMGlobalToLocal(), DMGlobalToLocalEnd(), DMGlobalToLocalBegin()

Level

beginner

Location

src/dm/interface/dm.c

Examples

src/dm/impls/stag/tutorials/ex1.c.html
src/dm/impls/stag/tutorials/ex2.c.html
src/dm/impls/stag/tutorials/ex3.c.html
src/dm/impls/stag/tutorials/ex6.c.html

Index of all DM routines
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Index of all manual pages