TESTING/LIN/dlavsy_rook.f(3)                          Library Functions Manual

NAME
       TESTING/LIN/dlavsy_rook.f

SYNOPSIS
   Functions/Subroutines
       subroutine dlavsy_rook (uplo, trans, diag, n, nrhs, a, lda, ipiv, b,
           ldb, info)
           DLAVSY_ROOK

Function/Subroutine Documentation
   subroutine dlavsy_rook (character uplo, character trans, character diag,
       integer n, integer nrhs, double precision, dimension( lda, * ) a,
       integer lda, integer, dimension( * ) ipiv, double precision, dimension(
       ldb, * ) b, integer ldb, integer info)
       DLAVSY_ROOK

       Purpose:


            DLAVSY_ROOK  performs one of the matrix-vector operations
               x := A*x  or  x := A'*x,
            where x is an N element vector and A is one of the factors
            from the block U*D*U' or L*D*L' factorization computed by DSYTRF_ROOK.

            If TRANS = 'N', multiplies by U  or U * D  (or L  or L * D)
            If TRANS = 'T', multiplies by U' or D * U' (or L' or D * L')
            If TRANS = 'C', multiplies by U' or D * U' (or L' or D * L')

       Parameters
           UPLO

                     UPLO is CHARACTER*1
                     Specifies whether the factor stored in A is upper or lower
                     triangular.
                     = 'U':  Upper triangular
                     = 'L':  Lower triangular

           TRANS

                     TRANS is CHARACTER*1
                     Specifies the operation to be performed:
                     = 'N':  x := A*x
                     = 'T':  x := A'*x
                     = 'C':  x := A'*x

           DIAG

                     DIAG is CHARACTER*1
                     Specifies whether or not the diagonal blocks are unit
                     matrices.  If the diagonal blocks are assumed to be unit,
                     then A = U or A = L, otherwise A = U*D or A = L*D.
                     = 'U':  Diagonal blocks are assumed to be unit matrices.
                     = 'N':  Diagonal blocks are assumed to be non-unit matrices.

           N

                     N is INTEGER
                     The number of rows and columns of the matrix A.  N >= 0.

           NRHS

                     NRHS is INTEGER
                     The number of right hand sides, i.e., the number of vectors
                     x to be multiplied by A.  NRHS >= 0.

           A

                     A is DOUBLE PRECISION array, dimension (LDA,N)
                     The block diagonal matrix D and the multipliers used to
                     obtain the factor U or L as computed by DSYTRF_ROOK.
                     Stored as a 2-D triangular matrix.

           LDA

                     LDA is INTEGER
                     The leading dimension of the array A.  LDA >= max(1,N).

           IPIV

                     IPIV is INTEGER array, dimension (N)
                     Details of the interchanges and the block structure of D,
                     as determined by DSYTRF_ROOK.

                     If UPLO = 'U':
                          If IPIV(k) > 0, then rows and columns k and IPIV(k)
                          were interchanged and D(k,k) is a 1-by-1 diagonal block.
                          (If IPIV( k ) = k, no interchange was done).

                          If IPIV(k) < 0 and IPIV(k-1) < 0, then rows and
                          columns k and -IPIV(k) were interchanged and rows and
                          columns k-1 and -IPIV(k-1) were inerchaged,
                          D(k-1:k,k-1:k) is a 2-by-2 diagonal block.

                     If UPLO = 'L':
                          If IPIV(k) > 0, then rows and columns k and IPIV(k)
                          were interchanged and D(k,k) is a 1-by-1 diagonal block.
                          (If IPIV( k ) = k, no interchange was done).

                          If IPIV(k) < 0 and IPIV(k+1) < 0, then rows and
                          columns k and -IPIV(k) were interchanged and rows and
                          columns k+1 and -IPIV(k+1) were inerchaged,
                          D(k:k+1,k:k+1) is a 2-by-2 diagonal block.

           B

                     B is DOUBLE PRECISION array, dimension (LDB,NRHS)
                     On entry, B contains NRHS vectors of length N.
                     On exit, B is overwritten with the product A * B.

           LDB

                     LDB is INTEGER
                     The leading dimension of the array B.  LDB >= max(1,N).

           INFO

                     INFO is INTEGER
                     = 0: successful exit
                     < 0: if INFO = -k, the k-th argument had an illegal value

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 155 of file dlavsy_rook.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0    TESTING/LIN/dlavsy_rook.f(3)