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

NAME
       TESTING/LIN/clavhp.f

SYNOPSIS
   Functions/Subroutines
       subroutine clavhp (uplo, trans, diag, n, nrhs, a, ipiv, b, ldb, info)
           CLAVHP

Function/Subroutine Documentation
   subroutine clavhp (character uplo, character trans, character diag, integer
       n, integer nrhs, complex, dimension( * ) a, integer, dimension( * )
       ipiv, complex, dimension( ldb, * ) b, integer ldb, integer info)
       CLAVHP

       Purpose:


               CLAVHP  performs one of the matrix-vector operations
                  x := A*x  or  x := A^H*x,
               where x is an N element vector and  A is one of the factors
               from the symmetric factorization computed by CHPTRF.
               CHPTRF produces a factorization of the form
                    U * D * U^H     or     L * D * L^H,
               where U (or L) is a product of permutation and unit upper (lower)
               triangular matrices, U^H (or L^H) is the conjugate transpose of
               U (or L), and D is Hermitian and block diagonal with 1 x 1 and
               2 x 2 diagonal blocks.  The multipliers for the transformations
               and the upper or lower triangular parts of the diagonal blocks
               are stored columnwise in packed format in the linear array A.

               If TRANS = 'N' or 'n', CLAVHP multiplies either by U or U * D
               (or L or L * D).
               If TRANS = 'C' or 'c', CLAVHP multiplies either by U^H or D * U^H
               (or L^H or D * L^H ).

             UPLO   - CHARACTER*1
                      On entry, UPLO specifies whether the triangular matrix
                      stored in A is upper or lower triangular.
                         UPLO = 'U' or 'u'   The matrix is upper triangular.
                         UPLO = 'L' or 'l'   The matrix is lower triangular.
                      Unchanged on exit.

             TRANS  - CHARACTER*1
                      On entry, TRANS specifies the operation to be performed as
                      follows:
                         TRANS = 'N' or 'n'   x := A*x.
                         TRANS = 'C' or 'c'   x := A^H*x.
                      Unchanged on exit.

             DIAG   - CHARACTER*1
                      On entry, DIAG specifies whether the diagonal blocks are
                      assumed to be unit matrices, as follows:
                         DIAG = 'U' or 'u'   Diagonal blocks are unit matrices.
                         DIAG = 'N' or 'n'   Diagonal blocks are non-unit.
                      Unchanged on exit.

             N      - INTEGER
                      On entry, N specifies the order of the matrix A.
                      N must be at least zero.
                      Unchanged on exit.

             NRHS   - INTEGER
                      On entry, NRHS specifies the number of right hand sides,
                      i.e., the number of vectors x to be multiplied by A.
                      NRHS must be at least zero.
                      Unchanged on exit.

             A      - COMPLEX array, dimension( N*(N+1)/2 )
                      On entry, A contains a block diagonal matrix and the
                      multipliers of the transformations used to obtain it,
                      stored as a packed triangular matrix.
                      Unchanged on exit.

             IPIV   - INTEGER array, dimension( N )
                      On entry, IPIV contains the vector of pivot indices as
                      determined by CSPTRF or CHPTRF.
                      If IPIV( K ) = K, no interchange was done.
                      If IPIV( K ) <> K but IPIV( K ) > 0, then row K was inter-
                      changed with row IPIV( K ) and a 1 x 1 pivot block was used.
                      If IPIV( K ) < 0 and UPLO = 'U', then row K-1 was exchanged
                      with row | IPIV( K ) | and a 2 x 2 pivot block was used.
                      If IPIV( K ) < 0 and UPLO = 'L', then row K+1 was exchanged
                      with row | IPIV( K ) | and a 2 x 2 pivot block was used.

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

             LDB    - INTEGER
                      On entry, LDB contains the leading dimension of B as
                      declared in the calling program.  LDB must be at least
                      max( 1, N ).
                      Unchanged on exit.

             INFO   - INTEGER
                      INFO is the error flag.
                      On exit, a value of 0 indicates a successful exit.
                      A negative value, say -K, indicates that the K-th argument
                      has an illegal value.

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 129 of file clavhp.f.

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

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