TESTING/MATGEN/claror.f(3)                            Library Functions Manual

NAME
       TESTING/MATGEN/claror.f

SYNOPSIS
   Functions/Subroutines
       subroutine claror (side, init, m, n, a, lda, iseed, x, info)
           CLAROR

Function/Subroutine Documentation
   subroutine claror (character side, character init, integer m, integer n,
       complex, dimension( lda, * ) a, integer lda, integer, dimension( 4 )
       iseed, complex, dimension( * ) x, integer info)
       CLAROR

       Purpose:


               CLAROR pre- or post-multiplies an M by N matrix A by a random
               unitary matrix U, overwriting A. A may optionally be
               initialized to the identity matrix before multiplying by U.
               U is generated using the method of G.W. Stewart
               ( SIAM J. Numer. Anal. 17, 1980, pp. 403-409 ).
               (BLAS-2 version)

       Parameters
           SIDE

                     SIDE is CHARACTER*1
                      SIDE specifies whether A is multiplied on the left or right
                      by U.
                  SIDE = 'L'   Multiply A on the left (premultiply) by U
                  SIDE = 'R'   Multiply A on the right (postmultiply) by UC>       SIDE = 'C'   Multiply A on the left by U and the right by UC>       SIDE = 'T'   Multiply A on the left by U and the right by U'
                      Not modified.

           INIT

                     INIT is CHARACTER*1
                      INIT specifies whether or not A should be initialized to
                      the identity matrix.
                         INIT = 'I'   Initialize A to (a section of) the
                                      identity matrix before applying U.
                         INIT = 'N'   No initialization.  Apply U to the
                                      input matrix A.

                      INIT = 'I' may be used to generate square (i.e., unitary)
                      or rectangular orthogonal matrices (orthogonality being
                      in the sense of CDOTC):

                      For square matrices, M=N, and SIDE many be either 'L' or
                      'R'; the rows will be orthogonal to each other, as will the
                      columns.
                      For rectangular matrices where M < N, SIDE = 'R' will
                      produce a dense matrix whose rows will be orthogonal and
                      whose columns will not, while SIDE = 'L' will produce a
                      matrix whose rows will be orthogonal, and whose first M
                      columns will be orthogonal, the remaining columns being
                      zero.
                      For matrices where M > N, just use the previous
                      explanation, interchanging 'L' and 'R' and 'rows' and
                      'columns'.

                      Not modified.

           M

                     M is INTEGER
                      Number of rows of A. Not modified.

           N

                     N is INTEGER
                      Number of columns of A. Not modified.

           A

                     A is COMPLEX array, dimension ( LDA, N )
                      Input and output array. Overwritten by U A ( if SIDE = 'L' )
                      or by A U ( if SIDE = 'R' )
                      or by U A U* ( if SIDE = 'C')
                      or by U A U' ( if SIDE = 'T') on exit.

           LDA

                     LDA is INTEGER
                      Leading dimension of A. Must be at least MAX ( 1, M ).
                      Not modified.

           ISEED

                     ISEED is INTEGER array, dimension ( 4 )
                      On entry ISEED specifies the seed of the random number
                      generator. The array elements should be between 0 and 4095;
                      if not they will be reduced mod 4096.  Also, ISEED(4) must
                      be odd.  The random number generator uses a linear
                      congruential sequence limited to small integers, and so
                      should produce machine independent random numbers. The
                      values of ISEED are changed on exit, and can be used in the
                      next call to CLAROR to continue the same random number
                      sequence.
                      Modified.

           X

                     X is COMPLEX array, dimension ( 3*MAX( M, N ) )
                      Workspace. Of length:
                          2*M + N if SIDE = 'L',
                          2*N + M if SIDE = 'R',
                          3*N     if SIDE = 'C' or 'T'.
                      Modified.

           INFO

                     INFO is INTEGER
                      An error flag.  It is set to:
                       0  if no error.
                       1  if CLARND returned a bad random number (installation
                          problem)
                      -1  if SIDE is not L, R, C, or T.
                      -3  if M is negative.
                      -4  if N is negative or if SIDE is C or T and N is not equal
                          to M.
                      -6  if LDA is less than M.

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 157 of file claror.f.

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

LAPACK                          Version 3.12.0      TESTING/MATGEN/claror.f(3)