Contents


NAME

     zbcomm - block coordinate matrix-matrix multiply

SYNOPSIS

       SUBROUTINE ZBCOMM( TRANSA, MB, N, KB, ALPHA, DESCRA,
      *           VAL, BINDX, BJNDX, BNNZ, LB,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER    TRANSA, MB, N, KB, DESCRA(5), BNNZ, LB,
      *           LDB, LDC, LWORK
       INTEGER    BINDX(BNNZ), BJNDX(BNNZ)
       DOUBLE COMPLEX ALPHA, BETA
       DOUBLE COMPLEX VAL(LB*LB*BNNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

       SUBROUTINE ZBCOMM_64( TRANSA, MB, N, KB, ALPHA, DESCRA,
      *           VAL, BINDX, BJNDX, BNNZ, LB,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER*8  TRANSA, MB, N, KB, DESCRA(5), BNNZ, LB,
      *           LDB, LDC, LWORK
       INTEGER*8  BINDX(BNNZ), BJNDX(BNNZ)
       DOUBLE COMPLEX ALPHA, BETA
       DOUBLE COMPLEX VAL(LB*LB*BNNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

     F95 INTERFACE

        SUBROUTINE BCOMM(TRANSA,MB,[N],KB,ALPHA,DESCRA,VAL,BINDX, BJNDX,
      *   BNNZ, LB, B, [LDB], BETA, C,[LDC], [WORK], [LWORK])
       INTEGER    TRANSA, MB, N, KB, BNNZ, LB
       INTEGER, DIMENSION(:) ::    DESCRA, BINDX, BJNDX
       DOUBLE COMPLEX    ALPHA, BETA
       DOUBLE COMPLEX, DIMENSION(:) :: VAL
       DOUBLE COMPLEX, DIMENSION(:, :) ::  B, C

        SUBROUTINE BCOMM_64(TRANSA,MB,[N],KB,ALPHA,DESCRA,VAL,BINDX, BJNDX,
      *   BNNZ, LB, B, [LDB], BETA, C,[LDC], [WORK], [LWORK])
       INTEGER*8    TRANSA, MB, N, KB, BNNZ, LB
       INTEGER*8, DIMENSION(:) ::   DESCRA, BINDX, BJNDX
       DOUBLE COMPLEX    ALPHA, BETA
       DOUBLE COMPLEX, DIMENSION(:) :: VAL
       DOUBLE COMPLEX, DIMENSION(:, :) ::  B, C

     C INTERFACE

     #include <sunperf.h>

     void zbcomm(int transa, int mb, int n, int kb, doublecomplex
     *alpha, int *descra, doublecomplex *val, int *bindx, int
     *bjndx, int bnnz, int lb,
      doublecomplex *b, int ldb, doublecomplex *beta,
     doublecomplex *c, int ldc);
     void zbcomm_64(long transa, long mb, long n, long kb,
     complex *alpha, long *descra, doublecomplex *val, long
     *bindx, long *bjndx, long bnnz, long lb, doublecomplex *b,
     long ldb,
      doublecomplex *beta, doublecomplex *c, long ldc);

DESCRIPTION

      cbcomm 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 (mb*lb) by (kb*lb) sparse matrix represented in the block
      coordinate format, alpha and beta  are scalars, C and B are dense
      matrices.

ARGUMENTS

      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.

      MB(input)       On entry,  MB  specifies the number of block rows
                      in matrix A. Unchanged on exit.

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

      KB(input)       On entry, KB specifies the number of block columns in
                      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 block 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,  scalar array of length LB*LB*BNNZ consisting of
                      the non-zero block entries of A, in any order.
                      Each block is stored in standard column-major form.
                      Unchanged on exit.

      BINDX(input)    On entry, integer array of length BNNZ consisting of the
                      block row indices of the non-zero block entries of A.
                      Unchanged on exit.

      BJNDX(input)    On entry, integer array of length BNNZ consisting of the
                      block column indices of the non-zero block entries of A.
                      Unchanged on exit.

      BNNZ (input)    On entry, BNNZ specifies the number of nonzero block
                      entries in A. Unchanged on exit.

      LB (input)      On entry, LB specifies the  dimension of dense blocks
                      composing A.  Unchanged on exit.

      B (input)       Array of DIMENSION ( LDB, N ).
                      Before entry with  TRANSA = 0,  the leading  kb*lb by n
                      part of the array  B  must contain the matrix  B,  otherwise
                      the leading  mb*lb 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  mb*lb by n
                      part of the array  C  must contain the matrix C,  otherwise
                      the leading  kb*lb 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
     complex matrix A for computing matrix-matrix multiply for
     another sparse matrix composed by block triangles and/or the
     main block diagonal of A. The full description of the
     feature for block entry formats is given in section
     NOTES/BUGS for the cbcomm manpage.