Contents


NAME

     dcoomm - coordinate matrix-matrix multiply

SYNOPSIS

       SUBROUTINE DCOOMM( TRANSA, M, N, K, ALPHA, DESCRA,
      *           VAL, INDX, JNDX, NNZ,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER    TRANSA, M, N, K, DESCRA(5), NNZ
      *           LDB, LDC, LWORK
       INTEGER    INDX(NNZ), JNDX(NNZ)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

       SUBROUTINE DCOOMM_64( TRANSA, M, N, K, ALPHA, DESCRA,
      *           VAL, INDX, JNDX, NNZ,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER*8  TRANSA, M, N, K, DESCRA(5), NNZ
      *           LDB, LDC, LWORK
       INTEGER*8  INDX(NNZ), JNDX(NNZ)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

     F95 INTERFACE

       SUBROUTINE COOMM( TRANSA, M, [N], K, ALPHA, DESCRA,
      *           VAL, INDX, JNDX, NNZ, B, [LDB], BETA, C, [LDC],
      *           [WORK], [LWORK] )
       INTEGER TRANSA, M, K,  NNZ
       INTEGER, DIMENSION(:) ::   DESCRA, INDX, JNDX
       DOUBLE PRECISION   ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) :: VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

       SUBROUTINE COOMM_64( TRANSA, M, [N], K, ALPHA, DESCRA,
      *           VAL, INDX, JNDX, NNZ, B, [LDB], BETA, C, [LDC],
      *           [WORK], [LWORK] )
       INTEGER*8 TRANSA, M, K,  NNZ
       INTEGER*8, DIMENSION(:) ::   DESCRA, INDX, JNDX
       DOUBLE PRECISION   ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) :: VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

     C INTERFACE

     #include <sunperf.h>

     void dcoomm (int transa, int m, int n, int k, double alpha,
     int *descra, double *val, int *indx, int *jndx, int nnz,
     double *b, int ldb, double beta, double *c, int ldc);
     void dcoomm_64 (long transa, long m, long n, long k,
      double alpha, long *descra, double *val, long *indx,
      long *jndx, long nnz, double *b, long ldb,
      double beta, double *c, long ldc);

DESCRIPTION

      dcoomm 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 coordinate format,
      alpha and beta are scalars, C and B are dense matrices.

ARGUMENTS

      TRANSA(input)   On entry, integer 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, integer M  specifies the number of rows in
                      the matrix A. Unchanged on exit.

      N(input)        On entry, integer N specifies the number of columns in
                      the matrix C. Unchanged on exit.

      K(input)        On entry, integer 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 array of length
                      NNZ consisting of the non-zero entries of A,
                      in any order. Unchanged on exit.

      INDX (input)    On entry, INDX is an integer array of length NNZ
                      consisting of the corresponding row indices of
                      the entries of A. Unchanged on exit.

      JNDX (input)    On entry, JNDX is an integer array of length NNZ
                      consisting of the corresponding column indices of
                      the entries of A. Unchanged on exit.

      NNZ (input)     On entry, integer NNZ specifies the number of
                      non-zero elements in A. 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 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 is given in section NOTES/BUGS for the scoomm
     manpage.