Contents


NAME

     djadmm - Jagged diagonal matrix-matrix multiply (modified
     Ellpack)

SYNOPSIS

       SUBROUTINE DJADMM( TRANSA, M, N, K, ALPHA, DESCRA,
      *           VAL, INDX, PNTR, MAXNZ, IPERM,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER    TRANSA, M, N, K, DESCRA(5), MAXNZ,
      *           LDB, LDC, LWORK
       INTEGER    INDX(NNZ), PNTR(MAXNZ+1), IPERM(M)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

       SUBROUTINE DJADMM_64( TRANSA, M, N, K, ALPHA, DESCRA,
      *           VAL, INDX, PNTR, MAXNZ, IPERM,
      *           B, LDB, BETA, C, LDC, WORK, LWORK)
       INTEGER*8  TRANSA, M, N, K, DESCRA(5), MAXNZ,
      *           LDB, LDC, LWORK
       INTEGER*8  INDX(NNZ), PNTR(MAXNZ+1), IPERM(M)
       DOUBLE PRECISION ALPHA, BETA
       DOUBLE PRECISION VAL(NNZ), B(LDB,*), C(LDC,*), WORK(LWORK)

      where NNZ=PNTR(MAXNZ+1)-PNTR(1)+1 is the number of non-zero elements.

     F95 INTERFACE

       SUBROUTINE JADMM( TRANSA, M, [N], K, ALPHA, DESCRA, VAL, INDX,
      *    PNTR, MAXNZ, IPERM, B, [LDB], BETA, C, [LDC], [WORK], [LWORK])
       INTEGER    TRANSA, M, K, MAXNZ
       INTEGER, DIMENSION(:) ::  DESCRA, INDX, PNTR, IPERM
       DOUBLE PRECISION    ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) ::  VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

       SUBROUTINE JADMM_64( TRANSA, M, [N], K, ALPHA, DESCRA, VAL, INDX,
      *    PNTR, MAXNZ, IPERM, B, [LDB], BETA, C, [LDC], [WORK], [LWORK])
       INTEGER*8     TRANSA, M, K, MAXNZ
       INTEGER*8, DIMENSION(:) ::  DESCRA, INDX, PNTR, IPERM
       DOUBLE PRECISION    ALPHA, BETA
       DOUBLE PRECISION, DIMENSION(:) ::  VAL
       DOUBLE PRECISION, DIMENSION(:, :) ::  B, C

     C INTERFACE

     #include <sunperf.h>

     void djadmm (int transa, int m, int n, int k, double alpha,
     int *descra, double *val, int *indx, int *pntr, int maxnz,
     int *iperm, double *b, int ldb, double beta, double *c, int
     ldc)

     void djadmm_64(long transa, long m, long n, long k, double
     alpha, long *descra, double *val, long *indx, long *pntr,
     long maxnz, long *iperm, double *b, long ldb, double beta,
     double *c,  long ldc);

DESCRIPTION

      djadmm 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 jagged diagonal 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.

      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=PNTR(MAXNZ+1)-PNTR(1)+1 consisting of entries of A.
                      VAL can be viewed as a column major ordering of a
                      row permutation of the Ellpack representation of A,
                      where the Ellpack representation is permuted so that
                      the rows are non-increasing in the number of nonzero
                      entries.  Values added for padding in Ellpack are
                      not included in the Jagged-Diagonal format.
                      Unchanged on exit.

      INDX(input)     On entry, INDX  is an integer array of length
                      NNZ=PNTR(MAXNZ+1)-PNTR(1)+1 consisting of the column
                      indices of the corresponding entries in VAL.
                      Unchanged on exit.

      PNTR(input)     On entry, PNTR is an integer  array of length
                      MAXNZ+1, where PNTR(I)-PNTR(1)+1 points to
                      the location in VAL of the first element
                      in the row-permuted Ellpack represenation of A.
                      Unchanged on exit.

      MAXNZ(input)    On entry,  MAXNZ  specifies the  max number of
                      nonzeros elements per row. Unchanged on exit.
      IPERM(input)    On entry, IPERM is an integer array of length M
                      such that I = IPERM(I'),  where row I in the
                      original Ellpack representation corresponds
                      to row I' in the permuted representation.
                      If IPERM(1) = 0, it is assumed by convention that
                      IPERM(I) = I. IPERM is used to determine the order
                      in which rows of C are updated. 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