NAME

diamm, sdiamm, ddiamm, cdiamm, zdiamm - diagonal format matrix-matrix multiply


SYNOPSIS

  SUBROUTINE SDIAMM( TRANSA, M, N, K, ALPHA, DESCRA,
 *           VAL, LDA, IDIAG, NDIAG,
 *           B, LDB, BETA, C, LDC, WORK, LWORK )
  INTEGER*4  TRANSA, M, N, K, DESCRA(5), LDA, NDIAG,
 *           LDB, LDC, LWORK
  INTEGER*4  IDIAG(NDIAG)
  REAL*4     ALPHA, BETA
  REAL*4     VAL(LDA,NDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)
  SUBROUTINE DDIAMM( TRANSA, M, N, K, ALPHA, DESCRA,
 *           VAL, LDA, IDIAG, NDIAG,
 *           B, LDB, BETA, C, LDC, WORK, LWORK)
  INTEGER*4  TRANSA, M, N, K, DESCRA(5), LDA, NDIAG,
 *           LDB, LDC, LWORK
  INTEGER*4  IDIAG(NDIAG)
  REAL*8     ALPHA, BETA
  REAL*8     VAL(LDA,NDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)
  SUBROUTINE CDIAMM( TRANSA, M, N, K, ALPHA, DESCRA,
 *           VAL, LDA, IDIAG, NDIAG,
 *           B, LDB, BETA, C, LDC, WORK, LWORK )
  INTEGER*4  TRANSA, M, N, K, DESCRA(5), LDA, NDIAG,
 *           LDB, LDC, LWORK
  INTEGER*4  IDIAG(NDIAG)
  COMPLEX*8  ALPHA, BETA
  COMPLEX*8  VAL(LDA,NDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)
  SUBROUTINE ZDIAMM( TRANSA, M, N, K, ALPHA, DESCRA,
 *           VAL, LDA, IDIAG, NDIAG,
 *           B, LDB, BETA, C, LDC, WORK, LWORK)
  INTEGER*4  TRANSA, M, N, K, DESCRA(5), LDA, NDIAG,
 *           LDB, LDC, LWORK
  INTEGER*4  IDIAG(NDIAG)
  COMPLEX*16 ALPHA, BETA
  COMPLEX*16 VAL(LDA,NDIAG), B(LDB,*), C(LDC,*), WORK(LWORK)


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 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.
 M             Number of rows in matrix A
 N             Number of columns in matrix C
 K             Number of columns in matrix A
 ALPHA         Scalar parameter
 DESCRA()      Descriptor argument.  Five element integer array
                 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 LDA-by-NDIAG array such that VAL(:,I)
               consists of non-zero elements on diagonal IDIAG(I)
               of A.  Diagonals in the lower triangular part of A
               are padded from the top, and those in the upper
               triangular part are padded from the bottom.
 LDA           leading dimension of VAL, must be .GE. MIN(M,K)
 IDIAG()       integer array of length NDIAG consisting of the
               corresponding diagonal offsets of the non-zero 
               diagonals of A in VAL.  Lower triangular diagonals 
               have negative offsets, the main diagonal has offset
               0, and upper triangular diagonals have positive offset.
 NDIAG         number of non-zero diagonals in 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/