ISPartitioningCount#
Takes a IS that represents a partitioning (the MPI rank that each local entry belongs to) and determines the number of resulting elements on each (partition) rank
Synopsis#
#include "petscis.h"
PetscErrorCode ISPartitioningCount(IS part, PetscInt len, PetscInt count[])
Collective
Input Parameters#
part - a partitioning as generated by
MatPartitioningApply()orMatPartitioningApplyND()len - length of the array count, this is the total number of partitions
Output Parameter#
count - array of length size, to contain the number of elements assigned to each partition, where size is the number of partitions generated (see notes below).
Notes#
By default the number of partitions generated (and thus the length
of count) is the size of the communicator associated with IS,
but it can be set by MatPartitioningSetNParts().
The resulting array of lengths can for instance serve as input of PCBJacobiSetTotalBlocks().
If the partitioning has been obtained by MatPartitioningApplyND(), the returned count does not include the separators.
See Also#
Low-level Vector Communication, IS, MatPartitioningCreate(), AOCreateBasic(), ISPartitioningToNumbering(),
MatPartitioningSetNParts(), MatPartitioningApply(), MatPartitioningApplyND()
Level#
advanced
Location#
src/vec/is/is/utils/iscoloring.c
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages