643 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Fortran
		
	
	
	
			
		
		
	
	
			643 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Fortran
		
	
	
	
| *> \brief \b CLATME
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| *
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| *  =========== DOCUMENTATION ===========
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| *
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| * Online html documentation available at
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| *            http://www.netlib.org/lapack/explore-html/
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| *
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| *  Definition:
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| *  ===========
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| *
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| *       SUBROUTINE CLATME( N, DIST, ISEED, D, MODE, COND, DMAX,
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| *         RSIGN,
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| *                          UPPER, SIM, DS, MODES, CONDS, KL, KU, ANORM,
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| *         A,
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| *                          LDA, WORK, INFO )
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| *
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| *       .. Scalar Arguments ..
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| *       CHARACTER          DIST, RSIGN, SIM, UPPER
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| *       INTEGER            INFO, KL, KU, LDA, MODE, MODES, N
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| *       REAL               ANORM, COND, CONDS
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| *       COMPLEX            DMAX
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| *       ..
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| *       .. Array Arguments ..
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| *       INTEGER            ISEED( 4 )
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| *       REAL               DS( * )
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| *       COMPLEX            A( LDA, * ), D( * ), WORK( * )
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| *       ..
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| *
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| *
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| *> \par Purpose:
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| *  =============
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| *>
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| *> \verbatim
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| *>
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| *>    CLATME generates random non-symmetric square matrices with
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| *>    specified eigenvalues for testing LAPACK programs.
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| *>
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| *>    CLATME operates by applying the following sequence of
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| *>    operations:
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| *>
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| *>    1. Set the diagonal to D, where D may be input or
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| *>         computed according to MODE, COND, DMAX, and RSIGN
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| *>         as described below.
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| *>
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| *>    2. If UPPER='T', the upper triangle of A is set to random values
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| *>         out of distribution DIST.
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| *>
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| *>    3. If SIM='T', A is multiplied on the left by a random matrix
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| *>         X, whose singular values are specified by DS, MODES, and
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| *>         CONDS, and on the right by X inverse.
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| *>
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| *>    4. If KL < N-1, the lower bandwidth is reduced to KL using
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| *>         Householder transformations.  If KU < N-1, the upper
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| *>         bandwidth is reduced to KU.
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| *>
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| *>    5. If ANORM is not negative, the matrix is scaled to have
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| *>         maximum-element-norm ANORM.
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| *>
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| *>    (Note: since the matrix cannot be reduced beyond Hessenberg form,
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| *>     no packing options are available.)
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| *> \endverbatim
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| *
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| *  Arguments:
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| *  ==========
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| *
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| *> \param[in] N
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| *> \verbatim
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| *>          N is INTEGER
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| *>           The number of columns (or rows) of A. Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] DIST
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| *> \verbatim
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| *>          DIST is CHARACTER*1
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| *>           On entry, DIST specifies the type of distribution to be used
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| *>           to generate the random eigen-/singular values, and on the
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| *>           upper triangle (see UPPER).
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| *>           'U' => UNIFORM( 0, 1 )  ( 'U' for uniform )
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| *>           'S' => UNIFORM( -1, 1 ) ( 'S' for symmetric )
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| *>           'N' => NORMAL( 0, 1 )   ( 'N' for normal )
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| *>           'D' => uniform on the complex disc |z| < 1.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in,out] ISEED
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| *> \verbatim
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| *>          ISEED is INTEGER array, dimension ( 4 )
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| *>           On entry ISEED specifies the seed of the random number
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| *>           generator. They should lie between 0 and 4095 inclusive,
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| *>           and ISEED(4) should be odd. The random number generator
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| *>           uses a linear congruential sequence limited to small
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| *>           integers, and so should produce machine independent
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| *>           random numbers. The values of ISEED are changed on
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| *>           exit, and can be used in the next call to CLATME
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| *>           to continue the same random number sequence.
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| *>           Changed on exit.
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| *> \endverbatim
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| *>
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| *> \param[in,out] D
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| *> \verbatim
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| *>          D is COMPLEX array, dimension ( N )
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| *>           This array is used to specify the eigenvalues of A.  If
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| *>           MODE=0, then D is assumed to contain the eigenvalues
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| *>           otherwise they will be computed according to MODE, COND,
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| *>           DMAX, and RSIGN and placed in D.
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| *>           Modified if MODE is nonzero.
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| *> \endverbatim
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| *>
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| *> \param[in] MODE
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| *> \verbatim
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| *>          MODE is INTEGER
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| *>           On entry this describes how the eigenvalues are to
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| *>           be specified:
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| *>           MODE = 0 means use D as input
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| *>           MODE = 1 sets D(1)=1 and D(2:N)=1.0/COND
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| *>           MODE = 2 sets D(1:N-1)=1 and D(N)=1.0/COND
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| *>           MODE = 3 sets D(I)=COND**(-(I-1)/(N-1))
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| *>           MODE = 4 sets D(i)=1 - (i-1)/(N-1)*(1 - 1/COND)
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| *>           MODE = 5 sets D to random numbers in the range
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| *>                    ( 1/COND , 1 ) such that their logarithms
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| *>                    are uniformly distributed.
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| *>           MODE = 6 set D to random numbers from same distribution
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| *>                    as the rest of the matrix.
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| *>           MODE < 0 has the same meaning as ABS(MODE), except that
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| *>              the order of the elements of D is reversed.
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| *>           Thus if MODE is between 1 and 4, D has entries ranging
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| *>              from 1 to 1/COND, if between -1 and -4, D has entries
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| *>              ranging from 1/COND to 1,
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] COND
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| *> \verbatim
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| *>          COND is REAL
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| *>           On entry, this is used as described under MODE above.
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| *>           If used, it must be >= 1. Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] DMAX
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| *> \verbatim
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| *>          DMAX is COMPLEX
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| *>           If MODE is neither -6, 0 nor 6, the contents of D, as
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| *>           computed according to MODE and COND, will be scaled by
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| *>           DMAX / max(abs(D(i))).  Note that DMAX need not be
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| *>           positive or real: if DMAX is negative or complex (or zero),
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| *>           D will be scaled by a negative or complex number (or zero).
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| *>           If RSIGN='F' then the largest (absolute) eigenvalue will be
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| *>           equal to DMAX.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] RSIGN
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| *> \verbatim
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| *>          RSIGN is CHARACTER*1
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| *>           If MODE is not 0, 6, or -6, and RSIGN='T', then the
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| *>           elements of D, as computed according to MODE and COND, will
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| *>           be multiplied by a random complex number from the unit
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| *>           circle |z| = 1.  If RSIGN='F', they will not be.  RSIGN may
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| *>           only have the values 'T' or 'F'.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] UPPER
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| *> \verbatim
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| *>          UPPER is CHARACTER*1
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| *>           If UPPER='T', then the elements of A above the diagonal
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| *>           will be set to random numbers out of DIST.  If UPPER='F',
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| *>           they will not.  UPPER may only have the values 'T' or 'F'.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] SIM
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| *> \verbatim
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| *>          SIM is CHARACTER*1
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| *>           If SIM='T', then A will be operated on by a "similarity
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| *>           transform", i.e., multiplied on the left by a matrix X and
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| *>           on the right by X inverse.  X = U S V, where U and V are
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| *>           random unitary matrices and S is a (diagonal) matrix of
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| *>           singular values specified by DS, MODES, and CONDS.  If
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| *>           SIM='F', then A will not be transformed.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in,out] DS
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| *> \verbatim
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| *>          DS is REAL array, dimension ( N )
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| *>           This array is used to specify the singular values of X,
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| *>           in the same way that D specifies the eigenvalues of A.
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| *>           If MODE=0, the DS contains the singular values, which
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| *>           may not be zero.
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| *>           Modified if MODE is nonzero.
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| *> \endverbatim
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| *>
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| *> \param[in] MODES
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| *> \verbatim
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| *>          MODES is INTEGER
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| *> \endverbatim
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| *>
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| *> \param[in] CONDS
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| *> \verbatim
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| *>          CONDS is REAL
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| *>           Similar to MODE and COND, but for specifying the diagonal
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| *>           of S.  MODES=-6 and +6 are not allowed (since they would
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| *>           result in randomly ill-conditioned eigenvalues.)
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| *> \endverbatim
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| *>
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| *> \param[in] KL
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| *> \verbatim
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| *>          KL is INTEGER
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| *>           This specifies the lower bandwidth of the  matrix.  KL=1
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| *>           specifies upper Hessenberg form.  If KL is at least N-1,
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| *>           then A will have full lower bandwidth.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] KU
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| *> \verbatim
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| *>          KU is INTEGER
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| *>           This specifies the upper bandwidth of the  matrix.  KU=1
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| *>           specifies lower Hessenberg form.  If KU is at least N-1,
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| *>           then A will have full upper bandwidth; if KU and KL
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| *>           are both at least N-1, then A will be dense.  Only one of
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| *>           KU and KL may be less than N-1.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] ANORM
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| *> \verbatim
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| *>          ANORM is REAL
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| *>           If ANORM is not negative, then A will be scaled by a non-
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| *>           negative real number to make the maximum-element-norm of A
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| *>           to be ANORM.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[out] A
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| *> \verbatim
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| *>          A is COMPLEX array, dimension ( LDA, N )
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| *>           On exit A is the desired test matrix.
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| *>           Modified.
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| *> \endverbatim
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| *>
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| *> \param[in] LDA
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| *> \verbatim
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| *>          LDA is INTEGER
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| *>           LDA specifies the first dimension of A as declared in the
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| *>           calling program.  LDA must be at least M.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[out] WORK
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| *> \verbatim
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| *>          WORK is COMPLEX array, dimension ( 3*N )
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| *>           Workspace.
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| *>           Modified.
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| *> \endverbatim
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| *>
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| *> \param[out] INFO
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| *> \verbatim
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| *>          INFO is INTEGER
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| *>           Error code.  On exit, INFO will be set to one of the
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| *>           following values:
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| *>             0 => normal return
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| *>            -1 => N negative
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| *>            -2 => DIST illegal string
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| *>            -5 => MODE not in range -6 to 6
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| *>            -6 => COND less than 1.0, and MODE neither -6, 0 nor 6
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| *>            -9 => RSIGN is not 'T' or 'F'
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| *>           -10 => UPPER is not 'T' or 'F'
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| *>           -11 => SIM   is not 'T' or 'F'
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| *>           -12 => MODES=0 and DS has a zero singular value.
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| *>           -13 => MODES is not in the range -5 to 5.
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| *>           -14 => MODES is nonzero and CONDS is less than 1.
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| *>           -15 => KL is less than 1.
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| *>           -16 => KU is less than 1, or KL and KU are both less than
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| *>                  N-1.
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| *>           -19 => LDA is less than M.
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| *>            1  => Error return from CLATM1 (computing D)
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| *>            2  => Cannot scale to DMAX (max. eigenvalue is 0)
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| *>            3  => Error return from SLATM1 (computing DS)
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| *>            4  => Error return from CLARGE
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| *>            5  => Zero singular value from SLATM1.
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| *> \endverbatim
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| *
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| *  Authors:
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| *  ========
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| *
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| *> \author Univ. of Tennessee
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| *> \author Univ. of California Berkeley
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| *> \author Univ. of Colorado Denver
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| *> \author NAG Ltd.
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| *
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| *> \date December 2016
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| *
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| *> \ingroup complex_matgen
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| *
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| *  =====================================================================
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|       SUBROUTINE CLATME( N, DIST, ISEED, D, MODE, COND, DMAX,
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|      $  RSIGN,
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|      $                   UPPER, SIM, DS, MODES, CONDS, KL, KU, ANORM,
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|      $  A,
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|      $                   LDA, WORK, INFO )
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| *
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| *  -- LAPACK computational routine (version 3.7.0) --
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| *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
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| *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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| *     December 2016
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| *
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| *     .. Scalar Arguments ..
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|       CHARACTER          DIST, RSIGN, SIM, UPPER
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|       INTEGER            INFO, KL, KU, LDA, MODE, MODES, N
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|       REAL               ANORM, COND, CONDS
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|       COMPLEX            DMAX
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| *     ..
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| *     .. Array Arguments ..
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|       INTEGER            ISEED( 4 )
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|       REAL               DS( * )
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|       COMPLEX            A( LDA, * ), D( * ), WORK( * )
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| *     ..
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| *
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| *  =====================================================================
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| *
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| *     .. Parameters ..
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|       REAL               ZERO
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|       PARAMETER          ( ZERO = 0.0E+0 )
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|       REAL               ONE
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|       PARAMETER          ( ONE = 1.0E+0 )
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|       COMPLEX            CZERO
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|       PARAMETER          ( CZERO = ( 0.0E+0, 0.0E+0 ) )
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|       COMPLEX            CONE
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|       PARAMETER          ( CONE = ( 1.0E+0, 0.0E+0 ) )
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| *     ..
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| *     .. Local Scalars ..
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|       LOGICAL            BADS
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|       INTEGER            I, IC, ICOLS, IDIST, IINFO, IR, IROWS, IRSIGN,
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|      $                   ISIM, IUPPER, J, JC, JCR
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|       REAL               RALPHA, TEMP
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|       COMPLEX            ALPHA, TAU, XNORMS
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| *     ..
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| *     .. Local Arrays ..
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|       REAL               TEMPA( 1 )
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| *     ..
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| *     .. External Functions ..
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|       LOGICAL            LSAME
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|       REAL               CLANGE
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|       COMPLEX            CLARND
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|       EXTERNAL           LSAME, CLANGE, CLARND
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| *     ..
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| *     .. External Subroutines ..
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|       EXTERNAL           CCOPY, CGEMV, CGERC, CLACGV, CLARFG, CLARGE,
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|      $                   CLARNV, CLATM1, CLASET, CSCAL, CSSCAL, SLATM1,
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|      $                   XERBLA
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| *     ..
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| *     .. Intrinsic Functions ..
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|       INTRINSIC          ABS, CONJG, MAX, MOD
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| *     ..
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| *     .. Executable Statements ..
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| *
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| *     1)      Decode and Test the input parameters.
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| *             Initialize flags & seed.
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| *
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|       INFO = 0
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| *
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| *     Quick return if possible
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| *
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|       IF( N.EQ.0 )
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|      $   RETURN
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| *
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| *     Decode DIST
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| *
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|       IF( LSAME( DIST, 'U' ) ) THEN
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|          IDIST = 1
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|       ELSE IF( LSAME( DIST, 'S' ) ) THEN
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|          IDIST = 2
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|       ELSE IF( LSAME( DIST, 'N' ) ) THEN
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|          IDIST = 3
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|       ELSE IF( LSAME( DIST, 'D' ) ) THEN
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|          IDIST = 4
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|       ELSE
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|          IDIST = -1
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|       END IF
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| *
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| *     Decode RSIGN
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| *
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|       IF( LSAME( RSIGN, 'T' ) ) THEN
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|          IRSIGN = 1
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|       ELSE IF( LSAME( RSIGN, 'F' ) ) THEN
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|          IRSIGN = 0
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|       ELSE
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|          IRSIGN = -1
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|       END IF
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| *
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| *     Decode UPPER
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| *
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|       IF( LSAME( UPPER, 'T' ) ) THEN
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|          IUPPER = 1
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|       ELSE IF( LSAME( UPPER, 'F' ) ) THEN
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|          IUPPER = 0
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|       ELSE
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|          IUPPER = -1
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|       END IF
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| *
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| *     Decode SIM
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| *
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|       IF( LSAME( SIM, 'T' ) ) THEN
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|          ISIM = 1
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|       ELSE IF( LSAME( SIM, 'F' ) ) THEN
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|          ISIM = 0
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|       ELSE
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|          ISIM = -1
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|       END IF
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| *
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| *     Check DS, if MODES=0 and ISIM=1
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| *
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|       BADS = .FALSE.
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|       IF( MODES.EQ.0 .AND. ISIM.EQ.1 ) THEN
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|          DO 10 J = 1, N
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|             IF( DS( J ).EQ.ZERO )
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|      $         BADS = .TRUE.
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|    10    CONTINUE
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|       END IF
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| *
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| *     Set INFO if an error
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| *
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|       IF( N.LT.0 ) THEN
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|          INFO = -1
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|       ELSE IF( IDIST.EQ.-1 ) THEN
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|          INFO = -2
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|       ELSE IF( ABS( MODE ).GT.6 ) THEN
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|          INFO = -5
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|       ELSE IF( ( MODE.NE.0 .AND. ABS( MODE ).NE.6 ) .AND. COND.LT.ONE )
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|      $          THEN
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|          INFO = -6
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|       ELSE IF( IRSIGN.EQ.-1 ) THEN
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|          INFO = -9
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|       ELSE IF( IUPPER.EQ.-1 ) THEN
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|          INFO = -10
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|       ELSE IF( ISIM.EQ.-1 ) THEN
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|          INFO = -11
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|       ELSE IF( BADS ) THEN
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|          INFO = -12
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|       ELSE IF( ISIM.EQ.1 .AND. ABS( MODES ).GT.5 ) THEN
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|          INFO = -13
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|       ELSE IF( ISIM.EQ.1 .AND. MODES.NE.0 .AND. CONDS.LT.ONE ) THEN
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|          INFO = -14
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|       ELSE IF( KL.LT.1 ) THEN
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|          INFO = -15
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|       ELSE IF( KU.LT.1 .OR. ( KU.LT.N-1 .AND. KL.LT.N-1 ) ) THEN
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|          INFO = -16
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|       ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
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|          INFO = -19
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|       END IF
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| *
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|       IF( INFO.NE.0 ) THEN
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|          CALL XERBLA( 'CLATME', -INFO )
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|          RETURN
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|       END IF
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| *
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| *     Initialize random number generator
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| *
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|       DO 20 I = 1, 4
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|          ISEED( I ) = MOD( ABS( ISEED( I ) ), 4096 )
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|    20 CONTINUE
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| *
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|       IF( MOD( ISEED( 4 ), 2 ).NE.1 )
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|      $   ISEED( 4 ) = ISEED( 4 ) + 1
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| *
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| *     2)      Set up diagonal of A
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| *
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| *             Compute D according to COND and MODE
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| *
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|       CALL CLATM1( MODE, COND, IRSIGN, IDIST, ISEED, D, N, IINFO )
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|       IF( IINFO.NE.0 ) THEN
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|          INFO = 1
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|          RETURN
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|       END IF
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|       IF( MODE.NE.0 .AND. ABS( MODE ).NE.6 ) THEN
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| *
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| *        Scale by DMAX
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| *
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|          TEMP = ABS( D( 1 ) )
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|          DO 30 I = 2, N
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|             TEMP = MAX( TEMP, ABS( D( I ) ) )
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|    30    CONTINUE
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| *
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|          IF( TEMP.GT.ZERO ) THEN
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|             ALPHA = DMAX / TEMP
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|          ELSE
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|             INFO = 2
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|             RETURN
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|          END IF
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| *
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|          CALL CSCAL( N, ALPHA, D, 1 )
 | |
| *
 | |
|       END IF
 | |
| *
 | |
|       CALL CLASET( 'Full', N, N, CZERO, CZERO, A, LDA )
 | |
|       CALL CCOPY( N, D, 1, A, LDA+1 )
 | |
| *
 | |
| *     3)      If UPPER='T', set upper triangle of A to random numbers.
 | |
| *
 | |
|       IF( IUPPER.NE.0 ) THEN
 | |
|          DO 40 JC = 2, N
 | |
|             CALL CLARNV( IDIST, ISEED, JC-1, A( 1, JC ) )
 | |
|    40    CONTINUE
 | |
|       END IF
 | |
| *
 | |
| *     4)      If SIM='T', apply similarity transformation.
 | |
| *
 | |
| *                                -1
 | |
| *             Transform is  X A X  , where X = U S V, thus
 | |
| *
 | |
| *             it is  U S V A V' (1/S) U'
 | |
| *
 | |
|       IF( ISIM.NE.0 ) THEN
 | |
| *
 | |
| *        Compute S (singular values of the eigenvector matrix)
 | |
| *        according to CONDS and MODES
 | |
| *
 | |
|          CALL SLATM1( MODES, CONDS, 0, 0, ISEED, DS, N, IINFO )
 | |
|          IF( IINFO.NE.0 ) THEN
 | |
|             INFO = 3
 | |
|             RETURN
 | |
|          END IF
 | |
| *
 | |
| *        Multiply by V and V'
 | |
| *
 | |
|          CALL CLARGE( N, A, LDA, ISEED, WORK, IINFO )
 | |
|          IF( IINFO.NE.0 ) THEN
 | |
|             INFO = 4
 | |
|             RETURN
 | |
|          END IF
 | |
| *
 | |
| *        Multiply by S and (1/S)
 | |
| *
 | |
|          DO 50 J = 1, N
 | |
|             CALL CSSCAL( N, DS( J ), A( J, 1 ), LDA )
 | |
|             IF( DS( J ).NE.ZERO ) THEN
 | |
|                CALL CSSCAL( N, ONE / DS( J ), A( 1, J ), 1 )
 | |
|             ELSE
 | |
|                INFO = 5
 | |
|                RETURN
 | |
|             END IF
 | |
|    50    CONTINUE
 | |
| *
 | |
| *        Multiply by U and U'
 | |
| *
 | |
|          CALL CLARGE( N, A, LDA, ISEED, WORK, IINFO )
 | |
|          IF( IINFO.NE.0 ) THEN
 | |
|             INFO = 4
 | |
|             RETURN
 | |
|          END IF
 | |
|       END IF
 | |
| *
 | |
| *     5)      Reduce the bandwidth.
 | |
| *
 | |
|       IF( KL.LT.N-1 ) THEN
 | |
| *
 | |
| *        Reduce bandwidth -- kill column
 | |
| *
 | |
|          DO 60 JCR = KL + 1, N - 1
 | |
|             IC = JCR - KL
 | |
|             IROWS = N + 1 - JCR
 | |
|             ICOLS = N + KL - JCR
 | |
| *
 | |
|             CALL CCOPY( IROWS, A( JCR, IC ), 1, WORK, 1 )
 | |
|             XNORMS = WORK( 1 )
 | |
|             CALL CLARFG( IROWS, XNORMS, WORK( 2 ), 1, TAU )
 | |
|             TAU = CONJG( TAU )
 | |
|             WORK( 1 ) = CONE
 | |
|             ALPHA = CLARND( 5, ISEED )
 | |
| *
 | |
|             CALL CGEMV( 'C', IROWS, ICOLS, CONE, A( JCR, IC+1 ), LDA,
 | |
|      $                  WORK, 1, CZERO, WORK( IROWS+1 ), 1 )
 | |
|             CALL CGERC( IROWS, ICOLS, -TAU, WORK, 1, WORK( IROWS+1 ), 1,
 | |
|      $                  A( JCR, IC+1 ), LDA )
 | |
| *
 | |
|             CALL CGEMV( 'N', N, IROWS, CONE, A( 1, JCR ), LDA, WORK, 1,
 | |
|      $                  CZERO, WORK( IROWS+1 ), 1 )
 | |
|             CALL CGERC( N, IROWS, -CONJG( TAU ), WORK( IROWS+1 ), 1,
 | |
|      $                  WORK, 1, A( 1, JCR ), LDA )
 | |
| *
 | |
|             A( JCR, IC ) = XNORMS
 | |
|             CALL CLASET( 'Full', IROWS-1, 1, CZERO, CZERO,
 | |
|      $                   A( JCR+1, IC ), LDA )
 | |
| *
 | |
|             CALL CSCAL( ICOLS+1, ALPHA, A( JCR, IC ), LDA )
 | |
|             CALL CSCAL( N, CONJG( ALPHA ), A( 1, JCR ), 1 )
 | |
|    60    CONTINUE
 | |
|       ELSE IF( KU.LT.N-1 ) THEN
 | |
| *
 | |
| *        Reduce upper bandwidth -- kill a row at a time.
 | |
| *
 | |
|          DO 70 JCR = KU + 1, N - 1
 | |
|             IR = JCR - KU
 | |
|             IROWS = N + KU - JCR
 | |
|             ICOLS = N + 1 - JCR
 | |
| *
 | |
|             CALL CCOPY( ICOLS, A( IR, JCR ), LDA, WORK, 1 )
 | |
|             XNORMS = WORK( 1 )
 | |
|             CALL CLARFG( ICOLS, XNORMS, WORK( 2 ), 1, TAU )
 | |
|             TAU = CONJG( TAU )
 | |
|             WORK( 1 ) = CONE
 | |
|             CALL CLACGV( ICOLS-1, WORK( 2 ), 1 )
 | |
|             ALPHA = CLARND( 5, ISEED )
 | |
| *
 | |
|             CALL CGEMV( 'N', IROWS, ICOLS, CONE, A( IR+1, JCR ), LDA,
 | |
|      $                  WORK, 1, CZERO, WORK( ICOLS+1 ), 1 )
 | |
|             CALL CGERC( IROWS, ICOLS, -TAU, WORK( ICOLS+1 ), 1, WORK, 1,
 | |
|      $                  A( IR+1, JCR ), LDA )
 | |
| *
 | |
|             CALL CGEMV( 'C', ICOLS, N, CONE, A( JCR, 1 ), LDA, WORK, 1,
 | |
|      $                  CZERO, WORK( ICOLS+1 ), 1 )
 | |
|             CALL CGERC( ICOLS, N, -CONJG( TAU ), WORK, 1,
 | |
|      $                  WORK( ICOLS+1 ), 1, A( JCR, 1 ), LDA )
 | |
| *
 | |
|             A( IR, JCR ) = XNORMS
 | |
|             CALL CLASET( 'Full', 1, ICOLS-1, CZERO, CZERO,
 | |
|      $                   A( IR, JCR+1 ), LDA )
 | |
| *
 | |
|             CALL CSCAL( IROWS+1, ALPHA, A( IR, JCR ), 1 )
 | |
|             CALL CSCAL( N, CONJG( ALPHA ), A( JCR, 1 ), LDA )
 | |
|    70    CONTINUE
 | |
|       END IF
 | |
| *
 | |
| *     Scale the matrix to have norm ANORM
 | |
| *
 | |
|       IF( ANORM.GE.ZERO ) THEN
 | |
|          TEMP = CLANGE( 'M', N, N, A, LDA, TEMPA )
 | |
|          IF( TEMP.GT.ZERO ) THEN
 | |
|             RALPHA = ANORM / TEMP
 | |
|             DO 80 J = 1, N
 | |
|                CALL CSSCAL( N, RALPHA, A( 1, J ), 1 )
 | |
|    80       CONTINUE
 | |
|          END IF
 | |
|       END IF
 | |
| *
 | |
|       RETURN
 | |
| *
 | |
| *     End of CLATME
 | |
| *
 | |
|       END
 |