dcsrmm(3P) Sun Performance Library dcsrmm(3P)NAMEdcsrmm - compressed sparse row format matrix-matrix multiply
SYNOPSIS
SUBROUTINE DCSRMM( 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(M), PNTRE(M)
DOUBLE PRECISION ALPHA, BETA
DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)
SUBROUTINE DCSRMM_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(M), PNTRE(M)
DOUBLE PRECISION ALPHA, BETA
DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)
where NNZ = PNTRE(M)-PNTRB(1)
F95 INTERFACE
SUBROUTINE CSRMM( 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 PRECISION ALPHA, BETA
DOUBLE PRECISION, DIMENSION(:) :: VAL
DOUBLE PRECISION, DIMENSION(:, :) :: B, C
SUBROUTINE CSRMM_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 PRECISION ALPHA, BETA
DOUBLE PRECISION, DIMENSION(:) :: VAL
DOUBLE PRECISION, DIMENSION(:, :) :: B, C
C INTERFACE
#include <sunperf.h>
void dcsrmm (const int transa, const int m, const int n, const int k,
const double alpha, const int* descra, const double* val,
const int* indx, const int* pntrb, const int* pntre, const
double* b, const int ldb, const double beta, double* c, const
int ldc);
void dcsrmm_64 (const long transa, const long m, const long n, const
long k, const double alpha, const long* descra, const double*
val, const long* indx, const long* pntrb, const long* pntre,
const double* b, const long ldb, const double beta, double*
c, const long ldc);
DESCRIPTIONdcsrmm 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 row
format, alpha and beta are scalars, C and B are dense matrices.
ARGUMENTSTRANSA(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(M)-PNTRB(1) consisting of nonzero entries
of A. Unchanged on exit.
INDX(input) On entry, INDX is an integer array of length
NNZ = PNTRE(M)-PNTRB(1) consisting of the column
indices of nonzero entries of A. Unchanged on exit.
PNTRB(input) On entry, PNTRB is an integer array of length M such
that PNTRB(J)-PNTRB(1)+1 points to location in VAL
of the first nonzero element in row J.
Unchanged on exit.
PNTRE(input) On entry, PNTRE is an integer array of length M
such that PNTRE(J)-PNTRB(1) points to location
in VAL of the last nonzero element in row 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)
SEE ALSO
Libsunperf SPARSE BLAS is fully parallel and compatible with NIST FOR‐
TRAN 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 trian‐
gles and/or the main diagonal of A. The full description of the feature
for point entry formats is given in section NOTES/BUGS for the scoomm
manpage.
NOTES/BUGS
It is known that there exists another representation of the compressed
sparse row 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 row in the arrays VAL and INDX is used instead
of two arrays PNTRB and PNTRE. To use the routine with this kind of
compressed sparse row format the following calling sequence should be
used
SUBROUTINE DCSRMM( TRANSA, M, N, K, ALPHA, DESCRA,
* VAL, INDX, IA, IA(2), B, LDB, BETA,
* C, LDC, WORK, LWORK )
3rd Berkeley Distribution 6 Mar 2009 dcsrmm(3P)