Contents
zcscmm - compressed sparse column format matrix-matrix
multiply
SUBROUTINE ZCSCMM( TRANSA, M, N, K, ALPHA, DESCRA,
* VAL, INDX, PNTRB, PNTRE,
* B, LDB, BETA, C, LDC, WORK, LWORK)
INTEGER TRANSA, M, N, K, DESCRA(5),
* LDB, LDC, LWORK
INTEGER INDX(NNZ), PNTRB(K), PNTRE(K)
DOUBLE COMPLEX ALPHA, BETA
DOUBLE COMPLEX VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)
SUBROUTINE ZCSCMM_64( TRANSA, M, N, K, ALPHA, DESCRA,
* VAL, INDX, PNTRB, PNTRE,
* B, LDB, BETA, C, LDC, WORK, LWORK)
INTEGER*8 TRANSA, M, N, K, DESCRA(5),
* LDB, LDC, LWORK
INTEGER*8 INDX(NNZ), PNTRB(K), PNTRE(K)
DOUBLE COMPLEX ALPHA, BETA
DOUBLE COMPLEX VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)
where NNZ = PNTRE(K)-PNTRB(1)
F95 INTERFACE
SUBROUTINE CSCMM( TRANSA, M, [N], K, ALPHA, DESCRA, VAL, INDX,
* PNTRB, PNTRE, B, [LDB], BETA, C, [LDC], [WORK], [LWORK] )
INTEGER TRANSA, M, K
INTEGER, DIMENSION(:) :: DESCRA, INDX, PNTRB, PNTRE
DOUBLE COMPLEX ALPHA, BETA
DOUBLE COMPLEX, DIMENSION(:) :: VAL
DOUBLE COMPLEX, DIMENSION(:, :) :: B, C
SUBROUTINE CSCMM_64( TRANSA, M, [N], K, ALPHA, DESCRA, VAL, INDX,
* PNTRB, PNTRE, B, [LDB], BETA, C, [LDC], [WORK], [LWORK] )
INTEGER*8 TRANSA, M, K
INTEGER*8, DIMENSION(:) :: DESCRA, INDX, PNTRB, PNTRE
DOUBLE COMPLEX ALPHA, BETA
DOUBLE COMPLEX, DIMENSION(:) :: VAL
DOUBLE COMPLEX, DIMENSION(:, :) :: B, C
C INTERFACE
#include <sunperf.h>
void zcscmm(int transa, int m, int n, int k, doublecomplex
*alpha, int *descra, doublecomplex *val, int *indx, int
*pntrb, int *pntre, doublecomplex *b, int ldb,
doublecomplex *beta, doublecomplex* c, int ldc);
void zcscmm_64(long transa, long m, long n, long k,
doublecomplex *alpha, long *descra, doublecomplex *val, long
*indx, long *pntrb, long *pntre, doublecomplex *b, long ldb,
doublecomplex *beta, doublecomplex *c, long ldc);
zcscmm performs one of the matrix-matrix operations
C <- alpha op(A) B + beta C
where op( A ) is one of
op( A ) = A or op( A ) = A' or op( A ) = conjg( A' )
( ' indicates matrix transpose),
A is an M-by-K sparse matrix represented in the compressed sparse column
format, alpha and beta are scalars, C and B are dense matrices.
TRANSA(input) TRANSA specifies the form of op( A ) to be used in
the matrix multiplication as follows:
0 : operate with matrix
1 : operate with transpose matrix
2 : operate with the conjugate transpose of matrix.
2 is equivalent to 1 if matrix is real.
Unchanged on exit.
M(input) On entry, M specifies the number of rows in
the matrix A. Unchanged on exit.
N(input) On entry, N specifies the number of columns in
the matrix C. Unchanged on exit.
K(input) On entry, K specifies the number of columns
in the matrix A. Unchanged on exit.
ALPHA(input) On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
DESCRA (input) Descriptor argument. Five element integer array:
DESCRA(1) matrix structure
0 : general
1 : symmetric (A=A')
2 : Hermitian (A= CONJG(A'))
3 : Triangular
4 : Skew(Anti)-Symmetric (A=-A')
5 : Diagonal
6 : Skew-Hermitian (A= -CONJG(A'))
DESCRA(2) upper/lower triangular indicator
1 : lower
2 : upper
DESCRA(3) main diagonal type
0 : non-unit
1 : unit
DESCRA(4) Array base (NOT IMPLEMENTED)
0 : C/C++ compatible
1 : Fortran compatible
DESCRA(5) repeated indices? (NOT IMPLEMENTED)
0 : unknown
1 : no repeated indices
VAL(input) On entry, VAL is a scalar array of length
NNZ = PNTRE(K)-PNTRB(1) consisting of nonzero
entries of A. Unchanged on exit.
INDX(input) On entry, INDX is an integer array of length
NNZ = PNTRE(K)-PNTRB(1) consisting of the row
indices of nonzero entries of A.
Unchanged on exit.
PNTRB(input) On entry, PNTRB is an integer array of length K
such that PNTRB(J)-PNTRB(1)+1 points to location
in VAL of the first nonzero element in column J.
Unchanged on exit.
PNTRE(input) On entry, PNTRE is an integer array of length K
such that PNTRE(J)-PNTRB(1) points to location
in VAL of the last nonzero element in column J.
Unchanged on exit.
B (input) Array of DIMENSION ( LDB, N ).
Before entry with TRANSA = 0, the leading k by n
part of the array B must contain the matrix B, otherwise
the leading m by n part of the array B must contain the
matrix B. Unchanged on exit.
LDB (input) On entry, LDB specifies the first dimension of B as declared
in the calling (sub) program. Unchanged on exit.
BETA (input) On entry, BETA specifies the scalar beta. Unchanged on exit.
C(input/output) Array of DIMENSION ( LDC, N ).
Before entry with TRANSA = 0, the leading m by n
part of the array C must contain the matrix C, otherwise
the leading k by n part of the array C must contain the
matrix C. On exit, the array C is overwritten by the matrix
( alpha*op( A )* B + beta*C ).
LDC (input) On entry, LDC specifies the first dimension of C as declared
in the calling (sub) program. Unchanged on exit.
WORK (is not referenced in the current version)
LWORK (is not referenced in the current version)
Libsunperf SPARSE BLAS is fully parallel and compatible
with NIST FORTRAN Sparse Blas but the sources are different.
Libsunperf SPARSE BLAS is free of bugs found in NIST FORTRAN
Sparse Blas. Besides several new features and routines are
implemented.
NIST FORTRAN Sparse Blas User's Guide available at:
http://math.nist.gov/mcsd/Staff/KRemington/fspblas/
Based on the standard proposed in
"Document for the Basic Linear Algebra Subprograms (BLAS)
Standard", University of Tennessee, Knoxville, Tennessee,
1996:
http://www.netlib.org/utk/papers/sparse.ps
The routine is designed so that it provides a possibility to
use just one sparse matrix representation of a general
matrix A for computing matrix-matrix multiply for another
sparse matrix composed by triangles and/or the main
diagonal of A. The full description of the feature for point
entry formats in the case of complex matrices is given in
section NOTES/BUGS for the ccoomm manpage.
NOTES/BUGS
It is known that there exists another representation of the
compressed sparse column format (see for example Y.Saad,
"Iterative Methods for Sparse Linear Systems", WPS, 1996).
Its data structure consists of three array instead of the
four used in the current implementation. The main
difference is that only one array, IA, containing the
pointers to the beginning of each column in the arrays VAL
and INDX is used instead of two arrays PNTRB and PNTRE. To
use the routine with this kind of sparse column format the
following calling sequence should be used
SUBROUTINE ZCSCMM( TRANSA, M, N, K, ALPHA, DESCRA,
* VAL, INDX, IA, IA(2), B, LDB, BETA,
* C, LDC, WORK, LWORK )