PetscSFBcastBegin#

begin pointwise broadcast with root value being reduced to leaf value, to be concluded with call to PetscSFBcastEnd()

Synopsis#

#include "petscsf.h" 
PetscErrorCode PetscSFBcastBegin(PetscSF sf, MPI_Datatype unit, const void *rootdata, void *leafdata, MPI_Op op)

Collective

Input Parameters#

  • sf - star forest on which to communicate

  • unit - data type associated with each node

  • rootdata - buffer to broadcast

  • op - operation to use for reduction

Output Parameter#

  • leafdata - buffer to be reduced with values from each leaf’s respective root

Note#

When PETSc is configured with device support, it will use its own mechanism to figure out whether the given data pointers are host pointers or device pointers, which may incur a noticeable cost. If you already knew the info, you should use PetscSFBcastWithMemTypeBegin() instead.

See Also#

PetscSF, PetscSFBcastEnd(), PetscSFBcastWithMemTypeBegin()

Level#

intermediate

Location#

src/vec/is/sf/interface/sf.c

Examples#

src/ts/tutorials/ex11_sa.c
src/dm/impls/plex/tutorials/ex14.c
src/vec/is/sf/tutorials/ex1.c
src/vec/is/sf/tutorials/ex2.c
src/vec/is/sf/tutorials/ex3.c

Implementations#

PetscSFBcastBegin_Allgather() in src/vec/is/sf/impls/basic/allgather/sfallgather.c
PetscSFBcastBegin_Allgatherv() in src/vec/is/sf/impls/basic/allgatherv/sfallgatherv.c
PetscSFBcastBegin_Alltoall() in src/vec/is/sf/impls/basic/alltoall/sfalltoall.c
PetscSFBcastBegin_Gather() in src/vec/is/sf/impls/basic/gather/sfgather.c
PetscSFBcastBegin_Gatherv() in src/vec/is/sf/impls/basic/gatherv/sfgatherv.c
PetscSFBcastBegin_Neighbor() in src/vec/is/sf/impls/basic/neighbor/sfneighbor.c
PetscSFBcastBegin_Basic() in src/vec/is/sf/impls/basic/sfbasic.c
PetscSFBcastBegin_Window() in src/vec/is/sf/impls/window/sfwindow.c

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