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Diffstat (limited to 'intern/opennl/superlu/get_perm_c.c')
-rw-r--r-- | intern/opennl/superlu/get_perm_c.c | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/intern/opennl/superlu/get_perm_c.c b/intern/opennl/superlu/get_perm_c.c new file mode 100644 index 00000000000..9cdf5a876bf --- /dev/null +++ b/intern/opennl/superlu/get_perm_c.c @@ -0,0 +1,453 @@ +/* + * -- SuperLU routine (version 2.0) -- + * Univ. of California Berkeley, Xerox Palo Alto Research Center, + * and Lawrence Berkeley National Lab. + * November 15, 1997 + * + */ + +#include "ssp_defs.h" +#include "colamd.h" + +extern int genmmd_(int *, int *, int *, int *, int *, int *, int *, + int *, int *, int *, int *, int *); + +void +get_colamd( + const int m, /* number of rows in matrix A. */ + const int n, /* number of columns in matrix A. */ + const int nnz,/* number of nonzeros in matrix A. */ + int *colptr, /* column pointer of size n+1 for matrix A. */ + int *rowind, /* row indices of size nz for matrix A. */ + int *perm_c /* out - the column permutation vector. */ + ) +{ + int Alen, *A, i, info, *p; + double *knobs; + + Alen = colamd_recommended(nnz, m, n); + + if ( !(knobs = (double *) SUPERLU_MALLOC(COLAMD_KNOBS * sizeof(double))) ) + ABORT("Malloc fails for knobs"); + colamd_set_defaults(knobs); + + if (!(A = (int *) SUPERLU_MALLOC(Alen * sizeof(int))) ) + ABORT("Malloc fails for A[]"); + if (!(p = (int *) SUPERLU_MALLOC((n+1) * sizeof(int))) ) + ABORT("Malloc fails for p[]"); + for (i = 0; i <= n; ++i) p[i] = colptr[i]; + for (i = 0; i < nnz; ++i) A[i] = rowind[i]; + info = colamd(m, n, Alen, A, p, knobs); + if ( info == FALSE ) ABORT("COLAMD failed"); + + for (i = 0; i < n; ++i) perm_c[p[i]] = i; + + SUPERLU_FREE(knobs); + SUPERLU_FREE(A); + SUPERLU_FREE(p); +} + +void +getata( + const int m, /* number of rows in matrix A. */ + const int n, /* number of columns in matrix A. */ + const int nz, /* number of nonzeros in matrix A */ + int *colptr, /* column pointer of size n+1 for matrix A. */ + int *rowind, /* row indices of size nz for matrix A. */ + int *atanz, /* out - on exit, returns the actual number of + nonzeros in matrix A'*A. */ + int **ata_colptr, /* out - size n+1 */ + int **ata_rowind /* out - size *atanz */ + ) +/* + * 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? + * + */ +{ + register int i, j, k, col, num_nz, ti, trow; + int *marker, *b_colptr, *b_rowind; + int *t_colptr, *t_rowind; /* a column oriented form of T = A' */ + + if ( !(marker = (int*) SUPERLU_MALLOC((SUPERLU_MAX(m,n)+1)*sizeof(int))) ) + ABORT("SUPERLU_MALLOC fails for marker[]"); + if ( !(t_colptr = (int*) SUPERLU_MALLOC((m+1) * sizeof(int))) ) + ABORT("SUPERLU_MALLOC t_colptr[]"); + if ( !(t_rowind = (int*) SUPERLU_MALLOC(nz * sizeof(int))) ) + ABORT("SUPERLU_MALLOC fails for t_rowind[]"); + + + /* Get counts of each column of T, and set up column pointers */ + for (i = 0; i < m; ++i) marker[i] = 0; + for (j = 0; j < n; ++j) { + for (i = colptr[j]; i < colptr[j+1]; ++i) + ++marker[rowind[i]]; + } + t_colptr[0] = 0; + for (i = 0; i < m; ++i) { + t_colptr[i+1] = t_colptr[i] + marker[i]; + marker[i] = t_colptr[i]; + } + + /* Transpose the matrix from A to T */ + for (j = 0; j < n; ++j) + for (i = colptr[j]; i < colptr[j+1]; ++i) { + col = rowind[i]; + t_rowind[marker[col]] = j; + ++marker[col]; + } + + + /* ---------------------------------------------------------------- + compute B = T * A, where column j of B is: + + Struct (B_*j) = UNION ( Struct (T_*k) ) + A_kj != 0 + + do not include the diagonal entry + + ( Partition A as: A = (A_*1, ..., A_*n) + Then B = T * A = (T * A_*1, ..., T * A_*n), where + T * A_*j = (T_*1, ..., T_*m) * A_*j. ) + ---------------------------------------------------------------- */ + + /* Zero the diagonal flag */ + for (i = 0; i < n; ++i) marker[i] = -1; + + /* First pass determines number of nonzeros in B */ + num_nz = 0; + for (j = 0; j < n; ++j) { + /* Flag the diagonal so it's not included in the B matrix */ + marker[j] = j; + + for (i = colptr[j]; i < colptr[j+1]; ++i) { + /* A_kj is nonzero, add pattern of column T_*k to B_*j */ + k = rowind[i]; + for (ti = t_colptr[k]; ti < t_colptr[k+1]; ++ti) { + trow = t_rowind[ti]; + if ( marker[trow] != j ) { + marker[trow] = j; + num_nz++; + } + } + } + } + *atanz = num_nz; + + /* Allocate storage for A'*A */ + if ( !(*ata_colptr = (int*) SUPERLU_MALLOC( (n+1) * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for ata_colptr[]"); + if ( *atanz ) { + if ( !(*ata_rowind = (int*) SUPERLU_MALLOC( *atanz * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for ata_rowind[]"); + } + b_colptr = *ata_colptr; /* aliasing */ + b_rowind = *ata_rowind; + + /* Zero the diagonal flag */ + for (i = 0; i < n; ++i) marker[i] = -1; + + /* Compute each column of B, one at a time */ + num_nz = 0; + for (j = 0; j < n; ++j) { + b_colptr[j] = num_nz; + + /* Flag the diagonal so it's not included in the B matrix */ + marker[j] = j; + + for (i = colptr[j]; i < colptr[j+1]; ++i) { + /* A_kj is nonzero, add pattern of column T_*k to B_*j */ + k = rowind[i]; + for (ti = t_colptr[k]; ti < t_colptr[k+1]; ++ti) { + trow = t_rowind[ti]; + if ( marker[trow] != j ) { + marker[trow] = j; + b_rowind[num_nz++] = trow; + } + } + } + } + b_colptr[n] = num_nz; + + SUPERLU_FREE(marker); + SUPERLU_FREE(t_colptr); + SUPERLU_FREE(t_rowind); +} + + +void +at_plus_a( + const int n, /* number of columns in matrix A. */ + const int nz, /* number of nonzeros in matrix A */ + int *colptr, /* column pointer of size n+1 for matrix A. */ + int *rowind, /* row indices of size nz for matrix A. */ + int *bnz, /* out - on exit, returns the actual number of + nonzeros in matrix A'*A. */ + int **b_colptr, /* out - size n+1 */ + int **b_rowind /* out - size *bnz */ + ) +{ +/* + * 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). + * + */ + register int i, j, k, col, num_nz; + int *t_colptr, *t_rowind; /* a column oriented form of T = A' */ + int *marker; + + if ( !(marker = (int*) SUPERLU_MALLOC( n * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for marker[]"); + if ( !(t_colptr = (int*) SUPERLU_MALLOC( (n+1) * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for t_colptr[]"); + if ( !(t_rowind = (int*) SUPERLU_MALLOC( nz * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails t_rowind[]"); + + + /* Get counts of each column of T, and set up column pointers */ + for (i = 0; i < n; ++i) marker[i] = 0; + for (j = 0; j < n; ++j) { + for (i = colptr[j]; i < colptr[j+1]; ++i) + ++marker[rowind[i]]; + } + t_colptr[0] = 0; + for (i = 0; i < n; ++i) { + t_colptr[i+1] = t_colptr[i] + marker[i]; + marker[i] = t_colptr[i]; + } + + /* Transpose the matrix from A to T */ + for (j = 0; j < n; ++j) + for (i = colptr[j]; i < colptr[j+1]; ++i) { + col = rowind[i]; + t_rowind[marker[col]] = j; + ++marker[col]; + } + + + /* ---------------------------------------------------------------- + compute B = A + T, where column j of B is: + + Struct (B_*j) = Struct (A_*k) UNION Struct (T_*k) + + do not include the diagonal entry + ---------------------------------------------------------------- */ + + /* Zero the diagonal flag */ + for (i = 0; i < n; ++i) marker[i] = -1; + + /* First pass determines number of nonzeros in B */ + num_nz = 0; + for (j = 0; j < n; ++j) { + /* Flag the diagonal so it's not included in the B matrix */ + marker[j] = j; + + /* Add pattern of column A_*k to B_*j */ + for (i = colptr[j]; i < colptr[j+1]; ++i) { + k = rowind[i]; + if ( marker[k] != j ) { + marker[k] = j; + ++num_nz; + } + } + + /* Add pattern of column T_*k to B_*j */ + for (i = t_colptr[j]; i < t_colptr[j+1]; ++i) { + k = t_rowind[i]; + if ( marker[k] != j ) { + marker[k] = j; + ++num_nz; + } + } + } + *bnz = num_nz; + + /* Allocate storage for A+A' */ + if ( !(*b_colptr = (int*) SUPERLU_MALLOC( (n+1) * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for b_colptr[]"); + if ( *bnz) { + if ( !(*b_rowind = (int*) SUPERLU_MALLOC( *bnz * sizeof(int)) ) ) + ABORT("SUPERLU_MALLOC fails for b_rowind[]"); + } + + /* Zero the diagonal flag */ + for (i = 0; i < n; ++i) marker[i] = -1; + + /* Compute each column of B, one at a time */ + num_nz = 0; + for (j = 0; j < n; ++j) { + (*b_colptr)[j] = num_nz; + + /* Flag the diagonal so it's not included in the B matrix */ + marker[j] = j; + + /* Add pattern of column A_*k to B_*j */ + for (i = colptr[j]; i < colptr[j+1]; ++i) { + k = rowind[i]; + if ( marker[k] != j ) { + marker[k] = j; + (*b_rowind)[num_nz++] = k; + } + } + + /* Add pattern of column T_*k to B_*j */ + for (i = t_colptr[j]; i < t_colptr[j+1]; ++i) { + k = t_rowind[i]; + if ( marker[k] != j ) { + marker[k] = j; + (*b_rowind)[num_nz++] = k; + } + } + } + (*b_colptr)[n] = num_nz; + + SUPERLU_FREE(marker); + SUPERLU_FREE(t_colptr); + SUPERLU_FREE(t_rowind); +} + +void +get_perm_c(int ispec, SuperMatrix *A, int *perm_c) +/* + * Purpose + * ======= + * + * GET_PERM_C 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) int + * Specifies the type of column ordering to reduce fill: + * = 1: minimum degree on the structure of A^T * A + * = 2: minimum degree on the structure of A^T + A + * = 3: approximate minimum degree for unsymmetric matrices + * If ispec == 0, the natural ordering (i.e., Pc = I) is returned. + * + * 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 = NC; Dtype = _D; Mtype = 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. + * + */ +{ + NCformat *Astore = A->Store; + int m, n, bnz, *b_colptr, i; + int delta, maxint, nofsub, *invp; + int *b_rowind, *dhead, *qsize, *llist, *marker; + double t, SuperLU_timer_(); + + m = A->nrow; + n = A->ncol; + + t = SuperLU_timer_(); + switch ( ispec ) { + case 0: /* Natural ordering */ + for (i = 0; i < n; ++i) perm_c[i] = i; +#if ( PRNTlevel>=1 ) + printf("Use natural column ordering.\n"); +#endif + return; + case 1: /* Minimum degree ordering on A'*A */ + getata(m, n, Astore->nnz, Astore->colptr, Astore->rowind, + &bnz, &b_colptr, &b_rowind); +#if ( PRNTlevel>=1 ) + printf("Use minimum degree ordering on A'*A.\n"); +#endif + t = SuperLU_timer_() - t; + /*printf("Form A'*A time = %8.3f\n", t);*/ + break; + case 2: /* Minimum degree ordering on A'+A */ + if ( m != n ) ABORT("Matrix is not square"); + at_plus_a(n, Astore->nnz, Astore->colptr, Astore->rowind, + &bnz, &b_colptr, &b_rowind); +#if ( PRNTlevel>=1 ) + printf("Use minimum degree ordering on A'+A.\n"); +#endif + t = SuperLU_timer_() - t; + /*printf("Form A'+A time = %8.3f\n", t);*/ + break; + case 3: /* Approximate minimum degree column ordering. */ + get_colamd(m, n, Astore->nnz, Astore->colptr, Astore->rowind, + perm_c); +#if ( PRNTlevel>=1 ) + printf(".. Use approximate minimum degree column ordering.\n"); +#endif + return; + default: + ABORT("Invalid ISPEC"); + } + + if ( bnz != 0 ) { + t = SuperLU_timer_(); + + /* Initialize and allocate storage for GENMMD. */ + delta = 1; /* DELTA is a parameter to allow the choice of nodes + whose degree <= min-degree + DELTA. */ + maxint = 2147483647; /* 2**31 - 1 */ + invp = (int *) SUPERLU_MALLOC((n+delta)*sizeof(int)); + if ( !invp ) ABORT("SUPERLU_MALLOC fails for invp."); + dhead = (int *) SUPERLU_MALLOC((n+delta)*sizeof(int)); + if ( !dhead ) ABORT("SUPERLU_MALLOC fails for dhead."); + qsize = (int *) SUPERLU_MALLOC((n+delta)*sizeof(int)); + if ( !qsize ) ABORT("SUPERLU_MALLOC fails for qsize."); + llist = (int *) SUPERLU_MALLOC(n*sizeof(int)); + if ( !llist ) ABORT("SUPERLU_MALLOC fails for llist."); + marker = (int *) SUPERLU_MALLOC(n*sizeof(int)); + if ( !marker ) ABORT("SUPERLU_MALLOC fails for marker."); + + /* Transform adjacency list into 1-based indexing required by GENMMD.*/ + for (i = 0; i <= n; ++i) ++b_colptr[i]; + for (i = 0; i < bnz; ++i) ++b_rowind[i]; + + genmmd_(&n, b_colptr, b_rowind, perm_c, invp, &delta, dhead, + qsize, llist, marker, &maxint, &nofsub); + + /* Transform perm_c into 0-based indexing. */ + for (i = 0; i < n; ++i) --perm_c[i]; + + SUPERLU_FREE(b_colptr); + SUPERLU_FREE(b_rowind); + SUPERLU_FREE(invp); + SUPERLU_FREE(dhead); + SUPERLU_FREE(qsize); + SUPERLU_FREE(llist); + SUPERLU_FREE(marker); + + t = SuperLU_timer_() - t; + /* printf("call GENMMD time = %8.3f\n", t);*/ + + } else { /* Empty adjacency structure */ + for (i = 0; i < n; ++i) perm_c[i] = i; + } + +} |