PetscSFCreateFromLayouts

Creates a parallel star forest mapping between two PetscLayout objects

Synopsis

#include "petscsf.h"   
PetscErrorCode PetscSFCreateFromLayouts(PetscLayout rmap, PetscLayout lmap, PetscSF *sf)

Collective

Input Parameters

• rmap - PetscLayout defining the global root space

• lmap - PetscLayout defining the global leaf space

Output Parameter

• sf - The parallel star forest

Notes

If the global length of lmap differs from the global length of rmap then the excess entries are ignored.

The resulting sf used with PetscSFBcastBegin() and PetscSFBcastEnd() merely copies the array entries of rootdata to leafdata; moving them between MPI processes if needed. For example, if rmap is [0, 3, 5) and lmap is [0, 2, 6) and rootdata is (1, 2, 3) on MPI rank 0 and (4, 5) on MPI rank 1 then the leafdata would become (1, 2) on MPI rank 0 and (3, 4, 5, x) on MPI rank 1.

See Also

PetscSF - an alternative to low-level MPI calls for data communication, PetscSF, PetscLayout, PetscSFCreate(), PetscSFSetGraph(), PetscLayoutCreate(), PetscSFSetGraphLayout()

Level

intermediate

Location

src/vec/is/sf/utils/sfutils.c

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Index of all PetscSF routines
Table of Contents for all manual pages
Index of all manual pages