Contents


NAME

     dbdimm - block diagonal format matrix-matrix multiply

SYNOPSIS

       SUBROUTINE DBDIMM( TRANSA, MB, N, KB, ALPHA, DESCRA,
      *           VAL, BLDA, IBDIAG, NBDIAG, LB,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER    TRANSA, MB, N, KB, DESCRA(5), BLDA, NBDIAG, LB,
      *           LDB, LDC, LWORK
       INTEGER    IBDIAG(NBDIAG)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(LB*LB*BLDA*NBDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)

       SUBROUTINE DBDIMM_64( TRANSA, MB, N, KB, ALPHA, DESCRA,
      *           VAL, BLDA, IBDIAG, NBDIAG, LB,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER*8  TRANSA, MB, N, KB, DESCRA(5), BLDA, NBDIAG, LB,
      *           LDB, LDC, LWORK
       INTEGER*8  IBDIAG(NBDIAG)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(LB*LB*BLDA*NBDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)

     F95 INTERFACE

        SUBROUTINE BDIMM(TRANSA,MB, [N], KB, ALPHA, DESCRA, VAL, BLDA,
      *    IBDIAG, NBDIAG, LB, B, [LDB], BETA, C, [LDC], [WORK], [LWORK])
       INTEGER    TRANSA, MB, KB, BLDA, NBDIAG, LB
       INTEGER, DIMENSION(:) ::    DESCRA, IBDIAG
       DOUBLE PRECISION    ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) :: VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

        SUBROUTINE BDIMM_64(TRANSA,MB, [N], KB, ALPHA, DESCRA, VAL, BLDA,
      *    IBDIAG, NBDIAG, LB, B, [LDB], BETA, C, [LDC], [WORK], [LWORK])
       INTEGER*8    TRANSA, MB, KB, BLDA, NBDIAG, LB
       INTEGER*8, DIMENSION(:) ::    DESCRA, IBDIAG
       DOUBLE PRECISION    ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) :: VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

DESCRIPTION

               C <- alpha op(A) B + beta C

      where ALPHA and BETA are scalar, C and B are dense matrices,
      A is a matrix represented in block diagonal format and
      op( A )  is one  of

      op( A ) = A   or   op( A ) = A'   or   op( A ) = conjg( A' ).
                                         ( ' indicates matrix transpose)

ARGUMENTS

      TRANSA        Indicates how to operate with the sparse matrix
                      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.

      MB            Number of block rows in matrix A

      N             Number of columns in matrix C

      KB            Number of block columns in matrix A

      ALPHA         Scalar parameter

      DESCRA()      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()         two-dimensional LB*LB*BLDA-by-NBDIAG scalar array
                    consisting of the NBDIAG nonzero block diagonal in
                    any order. Each dense block is stored in standard
                    column-major form.

      BLDA          leading block dimension of VAL().

      IBDIAG()      integer array of length NBDIAG consisting of the
                    corresponding diagonal offsets of the non-zero
                    block diagonals of A in VAL.  Lower triangular
                    block diagonals have negative offsets, the main
                    block diagonal has offset 0, and upper triangular
                    block diagonals have positive offset.

      NBDIAG        the number of non-zero block diagonals in A.
      LB            dimension of dense blocks composing A.

      B()           rectangular array with first dimension LDB.

      LDB           leading dimension of B

      BETA          Scalar parameter

      C()           rectangular array with first dimension LDC.

      LDC           leading dimension of C

      WORK()        scratch array of length LWORK. WORK is not
                    referenced in the current version.

      LWORK         length of WORK array. LWORK is not referenced
                    in the current version.

SEE ALSO

     NIST FORTRAN Sparse Blas User's Guide available at:

     http://math.nist.gov/mcsd/Staff/KRemington/fspblas/

     "Document for the Basic Linear Algebra Subprograms (BLAS)
     Standard", University of Tennessee, Knoxville, Tennessee,
     1996:

     http://www.netlib.org/utk/papers/sparse.ps