This module contains routines for translating global array indices into their local counterparts (that is, the indices into the local data structure holding a given process' chunk of a distributed array). The MCT domain decomposition descriptors GlobalMap and GlobalSegMap are both supported. Indices can be translated one-at-a-time using the GlobalToLocalIndex routine or many at once using the GlobalToLocalIndices routine.
This module also provides facilities for setting the local row and column indices for a SparseMatrix through the GlobalToLocalMatrix routines.
INTERFACE:
module m_GlobalToLocalUSES:
No external modules are used in the declaration section of this module.
implicit none
private ! except
PUBLIC MEMBER FUNCTIONS:
public :: GlobalToLocalIndex ! Translate Global to Local index
! (i.e. recover local index for a
! point from its global index).
public :: GlobalToLocalIndices ! Translate Global to Local indices
! (i.e. recover local starts/lengths
! of distributed data segments).
public :: GlobalToLocalMatrix ! Re-indexing of row or column
! indices for a SparseMatrix
interface GlobalToLocalIndices ; module procedure &
GlobalSegMapToIndices_, & ! local arrays of starts/lengths
GlobalSegMapToNavigator_, & ! return local indices as Navigator
GlobalSegMapToIndexArr_
end interface
interface GlobalToLocalIndex ; module procedure &
GlobalSegMapToIndex_, &
GlobalMapToIndex_
end interface
interface GlobalToLocalMatrix ; module procedure &
GlobalSegMapToLocalMatrix_
end interface
SEE ALSO:
The MCT modules {\tt m\_GlobalMap} and {m\_GlobalSegMap} for more
information regarding MCT's domain decomposition descriptors.
The MCT module {\tt m\_SparseMatrix} for more information regarding
the {\tt SparseMatrix} datatype.
REVISION HISTORY:
2Feb01 - J.W. Larson <[email protected]> - initial prototype
GlobalSegMapToIndices_() takes a user-supplied GlobalSegMap data type GSMap, which desribes a decomposition on the input MPI communicator corresponding to the Fortran INTEGER handle comm to translate the global directory of segment locations into local indices for referencing the on-pe storage of the mapped distributed data.
N.B.: This routine returns two allocated arrays--start(:) and length(:)--which must be deallocated once the user no longer needs them. Failure to do this will create a memory leak.
INTERFACE:
subroutine GlobalSegMapToIndices_(GSMap, comm, start, length)USES:
use m_mpif90
use m_die, only : MP_perr_die, die, warn
use m_GlobalSegMap, only : GlobalSegMap
use m_GlobalSegMap, only : GlobalSegMap_ngseg => ngseg
use m_GlobalSegMap, only : GlobalSegMap_nlseg => nlseg
implicit none
INPUT PARAMETERS:
type(GlobalSegMap), intent(in) :: GSMap ! Output GlobalSegMap
integer, intent(in) :: comm ! communicator handle
OUTPUT PARAMETERS:
integer,dimension(:), pointer :: start ! local segment start indices
integer,dimension(:), pointer :: length ! local segment sizes
REVISION HISTORY:
2Feb01 - J.W. Larson <[email protected]> - initial version
This INTEGER query function takes a user-supplied GlobalSegMap data type GSMap, which desribes a decomposition on the input MPI communicator corresponding to the Fortran INTEGER handle comm, and the input global index value i_g, and returns a positive local index value if the datum i_g. If the datum i_g is not stored on the local process ID, a value of -1 is returned.
INTERFACE:
integer function GlobalSegMapToIndex_(GSMap, i_g, comm)USES:
use m_mpif90
use m_die, only : MP_perr_die, die, warn
use m_GlobalSegMap, only : GlobalSegMap
use m_GlobalSegMap, only : GlobalSegMap_ngseg => ngseg
use m_GlobalSegMap, only : GlobalSegMap_nlseg => nlseg
implicit none
INPUT PARAMETERS:
type(GlobalSegMap), intent(in) :: GSMap ! Output GlobalSegMap
integer, intent(in) :: i_g ! global index
integer, intent(in) :: comm ! communicator handle
REVISION HISTORY:
2Feb01 - J.W. Larson <[email protected]> - initial version
Given a GlobalSegMap data type GSMap and MPI communicator corresponding to the Fortran INTEGER handle comm, convert an array of global index values i_global() to an array of local index values i_local(). If the datum i_global(j) is not stored on the local process ID, then i_local(j) will be set to -1/
INTERFACE:
subroutine GlobalSegMapToIndexArr_(GSMap, i_global, i_local, nindex, comm)USES:
use m_stdio
use m_mpif90
use m_die, only : MP_perr_die, die, warn
use m_GlobalSegMap, only : GlobalSegMap
use m_GlobalSegMap, only : GlobalSegMap_ngseg => ngseg
use m_GlobalSegMap, only : GlobalSegMap_nlseg => nlseg
implicit none
INPUT PARAMETERS:
type(GlobalSegMap), intent(in) :: GSMap ! Output GlobalSegMap
integer, intent(in) :: i_global(:) ! global index
integer, intent(out) :: i_local(:) ! local index
integer, intent(in) :: nindex ! size of i_global()
integer, intent(in) :: comm ! communicator handle
REVISION HISTORY:
12-apr-2006 R. Loy <[email protected]> - initial version
This INTEGER query function takes as its input a user-supplied GlobalMap data type GMap, which desribes a decomposition on the input MPI communicator corresponding to the Fortran INTEGER handle comm, and the input global index value i_g, and returns a positive local index value if the datum i_g. If the datum i_g is not stored on the local process ID, a value of -1 is returned.
INTERFACE:
integer function GlobalMapToIndex_(GMap, i_g, comm)USES:
use m_mpif90
use m_die, only : MP_perr_die, die, warn
use m_GlobalMap, only : GlobalMap
implicit none
INPUT PARAMETERS:
type(GlobalMap), intent(in) :: GMap ! Input GlobalMap
integer, intent(in) :: i_g ! global index
integer, intent(in) :: comm ! communicator handle
REVISION HISTORY:
2Feb01 - J.W. Larson <[email protected]> - initial version
This routine takes as its input takes a user-supplied GlobalSegMap data type GSMap, which desribes a decomposition on the input MPI communicator corresponding to the Fortran INTEGER handle comm, and returns the local segment start index and length information for referencing the on-pe storage of the mapped distributed data. These data are returned in the form of the output Navigator argument Nav.
N.B.: This routine returns a Navigator variable Nav, which must be deallocated once the user no longer needs it. Failure to do this will create a memory leak.
INTERFACE:
subroutine GlobalSegMapToNavigator_(GSMap, comm, oNav)USES:
use m_mpif90
use m_die, only : MP_perr_die, die, warn
use m_GlobalSegMap, only : GlobalSegMap
use m_GlobalSegMap, only : GlobalSegMap_ngseg => ngseg
use m_GlobalSegMap, only : GlobalSegMap_nlseg => nlseg
use m_Navigator, only : Navigator
use m_Navigator, only : Navigator_init => init
implicit none
INPUT PARAMETERS:
type(GlobalSegMap), intent(in) :: GSMap ! Input GlobalSegMap
integer, intent(in) :: comm ! communicator handle
OUTPUT PARAMETERS:
type(Navigator), intent(out) :: oNav ! Output Navigator
REVISION HISTORY:
2Feb01 - J.W. Larson <[email protected]> - initial version
This routine takes as its input a user-supplied GlobalSegMap domain decomposition GSMap, which describes the decomposition of either the rows or columns of the input/output SparseMatrix argument sMat on the communicator associated with the INTEGER handle comm, and to translate the global row or column indices of sMat into their local counterparts. The choice of either row or column is governed by the value of the input CHARACTER argument RCFlag. One sets this variable to either 'ROW' or 'row' to specify row re-indexing (which are stored in sMat and retrieved by indexing the attribute lrow), and 'COLUMN' or 'column' to specify column re-indexing (which are stored in sMat and retrieved by indexing the SparseMatrix attribute lcol).
INTERFACE:
subroutine GlobalSegMapToLocalMatrix_(sMat, GSMap, RCFlag, comm)USES:
use m_stdio
use m_die, only : die
use m_SparseMatrix, only : SparseMatrix
use m_SparseMatrix, only : SparseMatrix_indexIA => indexIA
use m_SparseMatrix, only : SparseMatrix_lsize => lsize
use m_GlobalSegMap, only : GlobalSegMap
implicit none
INPUT PARAMETERS:
type(GlobalSegMap), intent(in) :: GSMap ! Input GlobalSegMap
character(len=*), intent(in) :: RCFlag ! 'row' or 'column'
integer, intent(in) :: comm ! communicator handle
INPUT/OUTPUT PARAMETERS:
type(SparseMatrix), intent(inout) :: sMat
SEE ALSO:
The MCT module m_SparseMatrix for more information about the SparseMatrix type and its storage of global and local row-and column indices.REVISION HISTORY:
3May01 - J.W. Larson <[email protected]> - initial version, which
is _extremely_ slow, but safe. This must be re-examined
later.