petsc-3.4.5 2014-06-29

PetscSFReduceBegin

begin reduction of leafdata into rootdata, to be completed with call to PetscSFReduceEnd()

Synopsis

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

Collective

Input Arguments

	sf	- star forest
	unit	- data type
	leafdata	- values to reduce
	op	- reduction operation

Output Arguments

rootdata -result of reduction of values from all leaves of each root

See Also

PetscSFBcastBegin()

Level:intermediate
Location:src/vec/is/sf/interface/sf.c
Index of all PetscSF routines
Table of Contents for all manual pages
Index of all manual pages

Examples

src/vec/is/sf/examples/tutorials/ex1.c.html