SuperLU_DIST  4.0
superlu_dist on CPU and GPU clusters
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get_perm_c_parmetis.c File Reference

Gets matrix permutation. More...

#include <limits.h>
#include <math.h>
#include "parmetis.h"
#include "superlu_ddefs.h"

Functions

float get_perm_c_parmetis (SuperMatrix *A, int_t *perm_r, int_t *perm_c, int nprocs_i, int noDomains, int_t **sizes, int_t **fstVtxSep, gridinfo_t *grid, MPI_Comm *metis_comm)
 

Detailed Description

Gets matrix permutation.

– Distributed symbolic factorization auxialiary routine  (version 2.1) –
Lawrence Berkeley National Lab, Univ. of California Berkeley - July 2003
INRIA France - January 2004
Laura Grigori
November 1, 2007

Function Documentation

float get_perm_c_parmetis ( SuperMatrix A,
int_t perm_r,
int_t perm_c,
int  nprocs_i,
int  noDomains,
int_t **  sizes,
int_t **  fstVtxSep,
gridinfo_t grid,
MPI_Comm *  metis_comm 
)

Purpose

GET_PERM_C_PARMETIS obtains a permutation matrix Pc, by applying a
graph partitioning algorithm to the symmetrized graph A+A'.  The
multilevel graph partitioning algorithm used is the
ParMETIS_V3_NodeND routine available in the parallel graph
partitioning package parMETIS.
The number of independent sub-domains noDomains computed by this
algorithm has to be a power of 2.  Hence noDomains is the larger
number power of 2 that is smaller than nprocs_i, where nprocs_i = nprow
* npcol is the number of processors used in SuperLU_DIST.

Arguments

A       (input) SuperMatrix*
        Matrix A in A*X=B, of dimension (A->nrow, A->ncol). The number
        of the linear equations is A->nrow.  Matrix A is distributed
        in NRformat_loc format.
perm_r  (input) int_t*
        Row permutation vector of size A->nrow, which defines the 
        permutation matrix Pr; perm_r[i] = j means row i of A is in 
        position j in Pr*A.
perm_c  (output) int_t*
    Column permutation vector of size A->ncol, which defines the 
        permutation matrix Pc; perm_c[i] = j means column i of A is 
        in position j in A*Pc.
nprocs_i (input) int*
        Number of processors the input matrix is distributed on in a block
        row format.  It corresponds to number of processors used in
        SuperLU_DIST.
noDomains (input) int*, must be power of 2
        Number of independent domains to be computed by the graph
        partitioning algorithm.  ( noDomains <= nprocs_i )
sizes   (output) int_t**, of size 2 * noDomains
        Returns pointer to an array containing the number of nodes
        for each sub-domain and each separator.  Separators are stored 
        from left to right.
        Memory for the array is allocated in this routine.
fstVtxSep (output) int_t**, of size 2 * noDomains
        Returns pointer to an array containing first node for each
        sub-domain and each separator.
        Memory for the array is allocated in this routine.

Return value

  < 0, number of bytes allocated on return from the symbolic factorization.

0, number of bytes allocated when out of memory.