ISListToPair#
Convert an IS list to a pair of IS of equal length defining an equivalent integer multimap. Each IS on the input list is assigned an integer j so that all of the indices of that IS are mapped to j.
Synopsis#
#include "petscis.h"
PetscErrorCode ISListToPair(MPI_Comm comm, PetscInt listlen, IS islist[], IS *xis, IS *yis)
Collective.
Input Parameters#
Output Parameters#
xis - domain
ISyis - range
IS
Notes#
The global integers assigned to the IS of the local input list might not correspond to the
local numbers of the IS on that list, but the two orderings are the same: the global
integers assigned to the IS on the local list form a strictly increasing sequence.
The IS on the input list can belong to subcommunicators of comm, and the subcommunicators
on the input IS list are assumed to be in a “deadlock-free” order.
Local lists of PetscObjects (or their subcomms) on a comm are “deadlock-free” if subcomm1
preceeds subcomm2 on any local list, then it preceeds subcomm2 on all ranks.
Equivalently, the local numbers of the subcomms on each local list are drawn from some global
numbering. This is ensured, for example, by ISPairToList().
See Also#
IS, ISPairToList()
Level#
developer
Location#
Index of all IS routines
Table of Contents for all manual pages
Index of all manual pages