SuperLU Distributed 8.2.1
Distributed memory sparse direct solver
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Gets matrix permutation. More...
Macros | |
#define | METISOPTIONS 40 |
Functions | |
void | get_metis_dist (int_t n, int_t bnz, int_t *b_colptr, int_t *b_rowind, int_t *perm_c) |
void | get_colamd_dist (const int m, const int n, const int nnz, int_t *colptr, int_t *rowind, int_t *perm_c) |
void | getata_dist (const int_t m, const int_t n, const int_t nz, int_t *colptr, int_t *rowind, int_t *atanz, int_t **ata_colptr, int_t **ata_rowind) |
void | at_plus_a_dist (const int_t n, const int_t nz, int_t *colptr, int_t *rowind, int_t *bnz, int_t **b_colptr, int_t **b_rowind) |
void | get_perm_c_dist (int_t pnum, int_t ispec, SuperMatrix *A, int_t *perm_c) |
Gets matrix permutation.
Copyright (c) 2003, The Regents of the University of California, through Lawrence Berkeley National Laboratory (subject to receipt of any required approvals from U.S. Dept. of Energy)
All rights reserved.
The source code is distributed under BSD license, see the file License.txt at the top-level directory.
-- Distributed SuperLU routine (version 2.1) -- Lawrence Berkeley National Lab, Univ. of California Berkeley, November 1, 2007 Feburary 20, 2008
Last update: 7/27/2011 fix a bug with metis ordering on empty graph.
#define METISOPTIONS 40 |
void at_plus_a_dist | ( | const int_t | n, |
const int_t | nz, | ||
int_t * | colptr, | ||
int_t * | rowind, | ||
int_t * | bnz, | ||
int_t ** | b_colptr, | ||
int_t ** | b_rowind | ||
) |
Purpose ======= Form the structure of A'+A. A is an n-by-n matrix in column oriented format represented by (colptr, rowind). The output A'+A is in column oriented format (symmetrically, also row oriented), represented by (b_colptr, b_rowind).
void get_colamd_dist | ( | const int | m, |
const int | n, | ||
const int | nnz, | ||
int_t * | colptr, | ||
int_t * | rowind, | ||
int_t * | perm_c | ||
) |
void get_perm_c_dist | ( | int_t | pnum, |
int_t | ispec, | ||
SuperMatrix * | A, | ||
int_t * | perm_c | ||
) |
Purpose ======= GET_PERM_C_DIST obtains a permutation matrix Pc, by applying the multiple minimum degree ordering code by Joseph Liu to matrix A'*A or A+A', or using approximate minimum degree column ordering by Davis et. al. The LU factorization of A*Pc tends to have less fill than the LU factorization of A. Arguments ========= ispec (input) colperm_t Specifies what type of column permutation to use to reduce fill. = NATURAL: natural ordering (i.e., Pc = I) = MMD_AT_PLUS_A: minimum degree ordering on structure of A'+A = MMD_ATA: minimum degree ordering on structure of A'*A = METIS_AT_PLUS_A: MeTis on A'+A A (input) SuperMatrix* Matrix A in A*X=B, of dimension (A->nrow, A->ncol). The number of the linear equations is A->nrow. Currently, the type of A can be: Stype = SLU_NC; Dtype = SLU_D; Mtype = SLU_GE. In the future, more general A can be handled. perm_c (output) int* 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.
void getata_dist | ( | const int_t | m, |
const int_t | n, | ||
const int_t | nz, | ||
int_t * | colptr, | ||
int_t * | rowind, | ||
int_t * | atanz, | ||
int_t ** | ata_colptr, | ||
int_t ** | ata_rowind | ||
) |
Purpose ======= Form the structure of A'*A. A is an m-by-n matrix in column oriented format represented by (colptr, rowind). The output A'*A is in column oriented format (symmetrically, also row oriented), represented by (ata_colptr, ata_rowind). This routine is modified from GETATA routine by Tim Davis. The complexity of this algorithm is: SUM_{i=1,m} r(i)^2, i.e., the sum of the square of the row counts. Questions ========= o Do I need to withhold the *dense* rows? o How do I know the number of nonzeros in A'*A?