1257 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			Fortran
		
	
	
	
			
		
		
	
	
			1257 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			Fortran
		
	
	
	
| *> \brief \b ZLATMS
 | |
| *
 | |
| *  =========== DOCUMENTATION ===========
 | |
| *
 | |
| * Online html documentation available at
 | |
| *            http://www.netlib.org/lapack/explore-html/
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| *
 | |
| *  Definition:
 | |
| *  ===========
 | |
| *
 | |
| *       SUBROUTINE ZLATMS( M, N, DIST, ISEED, SYM, D, MODE, COND, DMAX,
 | |
| *                          KL, KU, PACK, A, LDA, WORK, INFO )
 | |
| *
 | |
| *       .. Scalar Arguments ..
 | |
| *       CHARACTER          DIST, PACK, SYM
 | |
| *       INTEGER            INFO, KL, KU, LDA, M, MODE, N
 | |
| *       DOUBLE PRECISION   COND, DMAX
 | |
| *       ..
 | |
| *       .. Array Arguments ..
 | |
| *       INTEGER            ISEED( 4 )
 | |
| *       DOUBLE PRECISION   D( * )
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| *       COMPLEX*16         A( LDA, * ), WORK( * )
 | |
| *       ..
 | |
| *
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| *
 | |
| *> \par Purpose:
 | |
| *  =============
 | |
| *>
 | |
| *> \verbatim
 | |
| *>
 | |
| *>    ZLATMS generates random matrices with specified singular values
 | |
| *>    (or hermitian with specified eigenvalues)
 | |
| *>    for testing LAPACK programs.
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| *>
 | |
| *>    ZLATMS operates by applying the following sequence of
 | |
| *>    operations:
 | |
| *>
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| *>      Set the diagonal to D, where D may be input or
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| *>         computed according to MODE, COND, DMAX, and SYM
 | |
| *>         as described below.
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| *>
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| *>      Generate a matrix with the appropriate band structure, by one
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| *>         of two methods:
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| *>
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| *>      Method A:
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| *>          Generate a dense M x N matrix by multiplying D on the left
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| *>              and the right by random unitary matrices, then:
 | |
| *>
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| *>          Reduce the bandwidth according to KL and KU, using
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| *>              Householder transformations.
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| *>
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| *>      Method B:
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| *>          Convert the bandwidth-0 (i.e., diagonal) matrix to a
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| *>              bandwidth-1 matrix using Givens rotations, "chasing"
 | |
| *>              out-of-band elements back, much as in QR; then convert
 | |
| *>              the bandwidth-1 to a bandwidth-2 matrix, etc.  Note
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| *>              that for reasonably small bandwidths (relative to M and
 | |
| *>              N) this requires less storage, as a dense matrix is not
 | |
| *>              generated.  Also, for hermitian or symmetric matrices,
 | |
| *>              only one triangle is generated.
 | |
| *>
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| *>      Method A is chosen if the bandwidth is a large fraction of the
 | |
| *>          order of the matrix, and LDA is at least M (so a dense
 | |
| *>          matrix can be stored.)  Method B is chosen if the bandwidth
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| *>          is small (< 1/2 N for hermitian or symmetric, < .3 N+M for
 | |
| *>          non-symmetric), or LDA is less than M and not less than the
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| *>          bandwidth.
 | |
| *>
 | |
| *>      Pack the matrix if desired. Options specified by PACK are:
 | |
| *>         no packing
 | |
| *>         zero out upper half (if hermitian)
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| *>         zero out lower half (if hermitian)
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| *>         store the upper half columnwise (if hermitian or upper
 | |
| *>               triangular)
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| *>         store the lower half columnwise (if hermitian or lower
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| *>               triangular)
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| *>         store the lower triangle in banded format (if hermitian or
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| *>               lower triangular)
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| *>         store the upper triangle in banded format (if hermitian or
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| *>               upper triangular)
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| *>         store the entire matrix in banded format
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| *>      If Method B is chosen, and band format is specified, then the
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| *>         matrix will be generated in the band format, so no repacking
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| *>         will be necessary.
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| *> \endverbatim
 | |
| *
 | |
| *  Arguments:
 | |
| *  ==========
 | |
| *
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| *> \param[in] M
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| *> \verbatim
 | |
| *>          M is INTEGER
 | |
| *>           The number of rows of A. Not modified.
 | |
| *> \endverbatim
 | |
| *>
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| *> \param[in] N
 | |
| *> \verbatim
 | |
| *>          N is INTEGER
 | |
| *>           The number of columns of A. N must equal M if the matrix
 | |
| *>           is symmetric or hermitian (i.e., if SYM is not 'N')
 | |
| *>           Not modified.
 | |
| *> \endverbatim
 | |
| *>
 | |
| *> \param[in] DIST
 | |
| *> \verbatim
 | |
| *>          DIST is CHARACTER*1
 | |
| *>           On entry, DIST specifies the type of distribution to be used
 | |
| *>           to generate the random eigen-/singular values.
 | |
| *>           'U' => UNIFORM( 0, 1 )  ( 'U' for uniform )
 | |
| *>           'S' => UNIFORM( -1, 1 ) ( 'S' for symmetric )
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| *>           'N' => NORMAL( 0, 1 )   ( 'N' for normal )
 | |
| *>           Not modified.
 | |
| *> \endverbatim
 | |
| *>
 | |
| *> \param[in,out] ISEED
 | |
| *> \verbatim
 | |
| *>          ISEED is INTEGER array, dimension ( 4 )
 | |
| *>           On entry ISEED specifies the seed of the random number
 | |
| *>           generator. They should lie between 0 and 4095 inclusive,
 | |
| *>           and ISEED(4) should 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 ZLATMS
 | |
| *>           to continue the same random number sequence.
 | |
| *>           Changed on exit.
 | |
| *> \endverbatim
 | |
| *>
 | |
| *> \param[in] SYM
 | |
| *> \verbatim
 | |
| *>          SYM is CHARACTER*1
 | |
| *>           If SYM='H', the generated matrix is hermitian, with
 | |
| *>             eigenvalues specified by D, COND, MODE, and DMAX; they
 | |
| *>             may be positive, negative, or zero.
 | |
| *>           If SYM='P', the generated matrix is hermitian, with
 | |
| *>             eigenvalues (= singular values) specified by D, COND,
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| *>             MODE, and DMAX; they will not be negative.
 | |
| *>           If SYM='N', the generated matrix is nonsymmetric, with
 | |
| *>             singular values specified by D, COND, MODE, and DMAX;
 | |
| *>             they will not be negative.
 | |
| *>           If SYM='S', the generated matrix is (complex) symmetric,
 | |
| *>             with singular values specified by D, COND, MODE, and
 | |
| *>             DMAX; they will not be negative.
 | |
| *>           Not modified.
 | |
| *> \endverbatim
 | |
| *>
 | |
| *> \param[in,out] D
 | |
| *> \verbatim
 | |
| *>          D is DOUBLE PRECISION array, dimension ( MIN( M, N ) )
 | |
| *>           This array is used to specify the singular values or
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| *>           eigenvalues of A (see SYM, above.)  If MODE=0, then D is
 | |
| *>           assumed to contain the singular/eigenvalues, otherwise
 | |
| *>           they will be computed according to MODE, COND, and DMAX,
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| *>           and placed in D.
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| *>           Modified if MODE is nonzero.
 | |
| *> \endverbatim
 | |
| *>
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| *> \param[in] MODE
 | |
| *> \verbatim
 | |
| *>          MODE is INTEGER
 | |
| *>           On entry this describes how the singular/eigenvalues are to
 | |
| *>           be specified:
 | |
| *>           MODE = 0 means use D as input
 | |
| *>           MODE = 1 sets D(1)=1 and D(2:N)=1.0/COND
 | |
| *>           MODE = 2 sets D(1:N-1)=1 and D(N)=1.0/COND
 | |
| *>           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)
 | |
| *>           MODE = 5 sets D to random numbers in the range
 | |
| *>                    ( 1/COND , 1 ) such that their logarithms
 | |
| *>                    are uniformly distributed.
 | |
| *>           MODE = 6 set D to random numbers from same distribution
 | |
| *>                    as the rest of the matrix.
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| *>           MODE < 0 has the same meaning as ABS(MODE), except that
 | |
| *>              the order of the elements of D is reversed.
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| *>           Thus if MODE is positive, D has entries ranging from
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| *>              1 to 1/COND, if negative, from 1/COND to 1,
 | |
| *>           If SYM='H', and MODE is neither 0, 6, nor -6, then
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| *>              the elements of D will also be multiplied by a random
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| *>              sign (i.e., +1 or -1.)
 | |
| *>           Not modified.
 | |
| *> \endverbatim
 | |
| *>
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| *> \param[in] COND
 | |
| *> \verbatim
 | |
| *>          COND is DOUBLE PRECISION
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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.
 | |
| *> \endverbatim
 | |
| *>
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| *> \param[in] DMAX
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| *> \verbatim
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| *>          DMAX is DOUBLE PRECISION
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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))); thus, the maximum absolute eigen- or
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| *>           singular value (which is to say the norm) will be abs(DMAX).
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| *>           Note that DMAX need not be positive: if DMAX is negative
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| *>           (or zero), D will be scaled by a negative number (or zero).
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| *>           Not modified.
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| *> \endverbatim
 | |
| *>
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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. For
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| *>           example, KL=0 implies upper triangular, KL=1 implies upper
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| *>           Hessenberg, and KL being at least M-1 means that the matrix
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| *>           has full lower bandwidth.  KL must equal KU if the matrix
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| *>           is symmetric or hermitian.
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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. For
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| *>           example, KU=0 implies lower triangular, KU=1 implies lower
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| *>           Hessenberg, and KU being at least N-1 means that the matrix
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| *>           has full upper bandwidth.  KL must equal KU if the matrix
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| *>           is symmetric or hermitian.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in] PACK
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| *> \verbatim
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| *>          PACK is CHARACTER*1
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| *>           This specifies packing of matrix as follows:
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| *>           'N' => no packing
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| *>           'U' => zero out all subdiagonal entries (if symmetric
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| *>                  or hermitian)
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| *>           'L' => zero out all superdiagonal entries (if symmetric
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| *>                  or hermitian)
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| *>           'C' => store the upper triangle columnwise (only if the
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| *>                  matrix is symmetric, hermitian, or upper triangular)
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| *>           'R' => store the lower triangle columnwise (only if the
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| *>                  matrix is symmetric, hermitian, or lower triangular)
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| *>           'B' => store the lower triangle in band storage scheme
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| *>                  (only if the matrix is symmetric, hermitian, or
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| *>                  lower triangular)
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| *>           'Q' => store the upper triangle in band storage scheme
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| *>                  (only if the matrix is symmetric, hermitian, or
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| *>                  upper triangular)
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| *>           'Z' => store the entire matrix in band storage scheme
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| *>                      (pivoting can be provided for by using this
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| *>                      option to store A in the trailing rows of
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| *>                      the allocated storage)
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| *>
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| *>           Using these options, the various LAPACK packed and banded
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| *>           storage schemes can be obtained:
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| *>           GB                    - use 'Z'
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| *>           PB, SB, HB, or TB     - use 'B' or 'Q'
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| *>           PP, SP, HB, or TP     - use 'C' or 'R'
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| *>
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| *>           If two calls to ZLATMS differ only in the PACK parameter,
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| *>           they will generate mathematically equivalent matrices.
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| *>           Not modified.
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| *> \endverbatim
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| *>
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| *> \param[in,out] A
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| *> \verbatim
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| *>          A is COMPLEX*16 array, dimension ( LDA, N )
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| *>           On exit A is the desired test matrix.  A is first generated
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| *>           in full (unpacked) form, and then packed, if so specified
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| *>           by PACK.  Thus, the first M elements of the first N
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| *>           columns will always be modified.  If PACK specifies a
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| *>           packed or banded storage scheme, all LDA elements of the
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| *>           first N columns will be modified; the elements of the
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| *>           array which do not correspond to elements of the generated
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| *>           matrix are set to zero.
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| *>           Modified.
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| *> \endverbatim
 | |
| *>
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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.  If PACK='N', 'U', 'L', 'C', or 'R', then
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| *>           LDA must be at least M.  If PACK='B' or 'Q', then LDA must
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| *>           be at least MIN( KL, M-1) (which is equal to MIN(KU,N-1)).
 | |
| *>           If PACK='Z', LDA must be large enough to hold the packed
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| *>           array: MIN( KU, N-1) + MIN( KL, M-1) + 1.
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| *>           Not modified.
 | |
| *> \endverbatim
 | |
| *>
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| *> \param[out] WORK
 | |
| *> \verbatim
 | |
| *>          WORK is COMPLEX*16 array, dimension ( 3*MAX( N, M ) )
 | |
| *>           Workspace.
 | |
| *>           Modified.
 | |
| *> \endverbatim
 | |
| *>
 | |
| *> \param[out] INFO
 | |
| *> \verbatim
 | |
| *>          INFO is INTEGER
 | |
| *>           Error code.  On exit, INFO will be set to one of the
 | |
| *>           following values:
 | |
| *>             0 => normal return
 | |
| *>            -1 => M negative or unequal to N and SYM='S', 'H', or 'P'
 | |
| *>            -2 => N negative
 | |
| *>            -3 => DIST illegal string
 | |
| *>            -5 => SYM illegal string
 | |
| *>            -7 => MODE not in range -6 to 6
 | |
| *>            -8 => COND less than 1.0, and MODE neither -6, 0 nor 6
 | |
| *>           -10 => KL negative
 | |
| *>           -11 => KU negative, or SYM is not 'N' and KU is not equal to
 | |
| *>                  KL
 | |
| *>           -12 => PACK illegal string, or PACK='U' or 'L', and SYM='N';
 | |
| *>                  or PACK='C' or 'Q' and SYM='N' and KL is not zero;
 | |
| *>                  or PACK='R' or 'B' and SYM='N' and KU is not zero;
 | |
| *>                  or PACK='U', 'L', 'C', 'R', 'B', or 'Q', and M is not
 | |
| *>                  N.
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| *>           -14 => LDA is less than M, or PACK='Z' and LDA is less than
 | |
| *>                  MIN(KU,N-1) + MIN(KL,M-1) + 1.
 | |
| *>            1  => Error return from DLATM1
 | |
| *>            2  => Cannot scale to DMAX (max. sing. value is 0)
 | |
| *>            3  => Error return from ZLAGGE, CLAGHE or CLAGSY
 | |
| *> \endverbatim
 | |
| *
 | |
| *  Authors:
 | |
| *  ========
 | |
| *
 | |
| *> \author Univ. of Tennessee
 | |
| *> \author Univ. of California Berkeley
 | |
| *> \author Univ. of Colorado Denver
 | |
| *> \author NAG Ltd.
 | |
| *
 | |
| *> \date December 2016
 | |
| *
 | |
| *> \ingroup complex16_matgen
 | |
| *
 | |
| *  =====================================================================
 | |
|       SUBROUTINE ZLATMS( M, N, DIST, ISEED, SYM, D, MODE, COND, DMAX,
 | |
|      $                   KL, KU, PACK, A, LDA, WORK, INFO )
 | |
| *
 | |
| *  -- LAPACK computational routine (version 3.7.0) --
 | |
| *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 | |
| *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 | |
| *     December 2016
 | |
| *
 | |
| *     .. Scalar Arguments ..
 | |
|       CHARACTER          DIST, PACK, SYM
 | |
|       INTEGER            INFO, KL, KU, LDA, M, MODE, N
 | |
|       DOUBLE PRECISION   COND, DMAX
 | |
| *     ..
 | |
| *     .. Array Arguments ..
 | |
|       INTEGER            ISEED( 4 )
 | |
|       DOUBLE PRECISION   D( * )
 | |
|       COMPLEX*16         A( LDA, * ), WORK( * )
 | |
| *     ..
 | |
| *
 | |
| *  =====================================================================
 | |
| *
 | |
| *     .. Parameters ..
 | |
|       DOUBLE PRECISION   ZERO
 | |
|       PARAMETER          ( ZERO = 0.0D+0 )
 | |
|       DOUBLE PRECISION   ONE
 | |
|       PARAMETER          ( ONE = 1.0D+0 )
 | |
|       COMPLEX*16         CZERO
 | |
|       PARAMETER          ( CZERO = ( 0.0D+0, 0.0D+0 ) )
 | |
|       DOUBLE PRECISION   TWOPI
 | |
|       PARAMETER          ( TWOPI = 6.2831853071795864769252867663D+0 )
 | |
| *     ..
 | |
| *     .. Local Scalars ..
 | |
|       LOGICAL            GIVENS, ILEXTR, ILTEMP, TOPDWN, ZSYM
 | |
|       INTEGER            I, IC, ICOL, IDIST, IENDCH, IINFO, IL, ILDA,
 | |
|      $                   IOFFG, IOFFST, IPACK, IPACKG, IR, IR1, IR2,
 | |
|      $                   IROW, IRSIGN, ISKEW, ISYM, ISYMPK, J, JC, JCH,
 | |
|      $                   JKL, JKU, JR, K, LLB, MINLDA, MNMIN, MR, NC,
 | |
|      $                   UUB
 | |
|       DOUBLE PRECISION   ALPHA, ANGLE, REALC, TEMP
 | |
|       COMPLEX*16         C, CT, CTEMP, DUMMY, EXTRA, S, ST
 | |
| *     ..
 | |
| *     .. External Functions ..
 | |
|       LOGICAL            LSAME
 | |
|       DOUBLE PRECISION   DLARND
 | |
|       COMPLEX*16         ZLARND
 | |
|       EXTERNAL           LSAME, DLARND, ZLARND
 | |
| *     ..
 | |
| *     .. External Subroutines ..
 | |
|       EXTERNAL           DLATM1, DSCAL, XERBLA, ZLAGGE, ZLAGHE, ZLAGSY,
 | |
|      $                   ZLAROT, ZLARTG, ZLASET
 | |
| *     ..
 | |
| *     .. Intrinsic Functions ..
 | |
|       INTRINSIC          ABS, COS, DBLE, DCMPLX, DCONJG, MAX, MIN, MOD,
 | |
|      $                   SIN
 | |
| *     ..
 | |
| *     .. Executable Statements ..
 | |
| *
 | |
| *     1)      Decode and Test the input parameters.
 | |
| *             Initialize flags & seed.
 | |
| *
 | |
|       INFO = 0
 | |
| *
 | |
| *     Quick return if possible
 | |
| *
 | |
|       IF( M.EQ.0 .OR. N.EQ.0 )
 | |
|      $   RETURN
 | |
| *
 | |
| *     Decode DIST
 | |
| *
 | |
|       IF( LSAME( DIST, 'U' ) ) THEN
 | |
|          IDIST = 1
 | |
|       ELSE IF( LSAME( DIST, 'S' ) ) THEN
 | |
|          IDIST = 2
 | |
|       ELSE IF( LSAME( DIST, 'N' ) ) THEN
 | |
|          IDIST = 3
 | |
|       ELSE
 | |
|          IDIST = -1
 | |
|       END IF
 | |
| *
 | |
| *     Decode SYM
 | |
| *
 | |
|       IF( LSAME( SYM, 'N' ) ) THEN
 | |
|          ISYM = 1
 | |
|          IRSIGN = 0
 | |
|          ZSYM = .FALSE.
 | |
|       ELSE IF( LSAME( SYM, 'P' ) ) THEN
 | |
|          ISYM = 2
 | |
|          IRSIGN = 0
 | |
|          ZSYM = .FALSE.
 | |
|       ELSE IF( LSAME( SYM, 'S' ) ) THEN
 | |
|          ISYM = 2
 | |
|          IRSIGN = 0
 | |
|          ZSYM = .TRUE.
 | |
|       ELSE IF( LSAME( SYM, 'H' ) ) THEN
 | |
|          ISYM = 2
 | |
|          IRSIGN = 1
 | |
|          ZSYM = .FALSE.
 | |
|       ELSE
 | |
|          ISYM = -1
 | |
|       END IF
 | |
| *
 | |
| *     Decode PACK
 | |
| *
 | |
|       ISYMPK = 0
 | |
|       IF( LSAME( PACK, 'N' ) ) THEN
 | |
|          IPACK = 0
 | |
|       ELSE IF( LSAME( PACK, 'U' ) ) THEN
 | |
|          IPACK = 1
 | |
|          ISYMPK = 1
 | |
|       ELSE IF( LSAME( PACK, 'L' ) ) THEN
 | |
|          IPACK = 2
 | |
|          ISYMPK = 1
 | |
|       ELSE IF( LSAME( PACK, 'C' ) ) THEN
 | |
|          IPACK = 3
 | |
|          ISYMPK = 2
 | |
|       ELSE IF( LSAME( PACK, 'R' ) ) THEN
 | |
|          IPACK = 4
 | |
|          ISYMPK = 3
 | |
|       ELSE IF( LSAME( PACK, 'B' ) ) THEN
 | |
|          IPACK = 5
 | |
|          ISYMPK = 3
 | |
|       ELSE IF( LSAME( PACK, 'Q' ) ) THEN
 | |
|          IPACK = 6
 | |
|          ISYMPK = 2
 | |
|       ELSE IF( LSAME( PACK, 'Z' ) ) THEN
 | |
|          IPACK = 7
 | |
|       ELSE
 | |
|          IPACK = -1
 | |
|       END IF
 | |
| *
 | |
| *     Set certain internal parameters
 | |
| *
 | |
|       MNMIN = MIN( M, N )
 | |
|       LLB = MIN( KL, M-1 )
 | |
|       UUB = MIN( KU, N-1 )
 | |
|       MR = MIN( M, N+LLB )
 | |
|       NC = MIN( N, M+UUB )
 | |
| *
 | |
|       IF( IPACK.EQ.5 .OR. IPACK.EQ.6 ) THEN
 | |
|          MINLDA = UUB + 1
 | |
|       ELSE IF( IPACK.EQ.7 ) THEN
 | |
|          MINLDA = LLB + UUB + 1
 | |
|       ELSE
 | |
|          MINLDA = M
 | |
|       END IF
 | |
| *
 | |
| *     Use Givens rotation method if bandwidth small enough,
 | |
| *     or if LDA is too small to store the matrix unpacked.
 | |
| *
 | |
|       GIVENS = .FALSE.
 | |
|       IF( ISYM.EQ.1 ) THEN
 | |
|          IF( DBLE( LLB+UUB ).LT.0.3D0*DBLE( MAX( 1, MR+NC ) ) )
 | |
|      $      GIVENS = .TRUE.
 | |
|       ELSE
 | |
|          IF( 2*LLB.LT.M )
 | |
|      $      GIVENS = .TRUE.
 | |
|       END IF
 | |
|       IF( LDA.LT.M .AND. LDA.GE.MINLDA )
 | |
|      $   GIVENS = .TRUE.
 | |
| *
 | |
| *     Set INFO if an error
 | |
| *
 | |
|       IF( M.LT.0 ) THEN
 | |
|          INFO = -1
 | |
|       ELSE IF( M.NE.N .AND. ISYM.NE.1 ) THEN
 | |
|          INFO = -1
 | |
|       ELSE IF( N.LT.0 ) THEN
 | |
|          INFO = -2
 | |
|       ELSE IF( IDIST.EQ.-1 ) THEN
 | |
|          INFO = -3
 | |
|       ELSE IF( ISYM.EQ.-1 ) THEN
 | |
|          INFO = -5
 | |
|       ELSE IF( ABS( MODE ).GT.6 ) THEN
 | |
|          INFO = -7
 | |
|       ELSE IF( ( MODE.NE.0 .AND. ABS( MODE ).NE.6 ) .AND. COND.LT.ONE )
 | |
|      $          THEN
 | |
|          INFO = -8
 | |
|       ELSE IF( KL.LT.0 ) THEN
 | |
|          INFO = -10
 | |
|       ELSE IF( KU.LT.0 .OR. ( ISYM.NE.1 .AND. KL.NE.KU ) ) THEN
 | |
|          INFO = -11
 | |
|       ELSE IF( IPACK.EQ.-1 .OR. ( ISYMPK.EQ.1 .AND. ISYM.EQ.1 ) .OR.
 | |
|      $         ( ISYMPK.EQ.2 .AND. ISYM.EQ.1 .AND. KL.GT.0 ) .OR.
 | |
|      $         ( ISYMPK.EQ.3 .AND. ISYM.EQ.1 .AND. KU.GT.0 ) .OR.
 | |
|      $         ( ISYMPK.NE.0 .AND. M.NE.N ) ) THEN
 | |
|          INFO = -12
 | |
|       ELSE IF( LDA.LT.MAX( 1, MINLDA ) ) THEN
 | |
|          INFO = -14
 | |
|       END IF
 | |
| *
 | |
|       IF( INFO.NE.0 ) THEN
 | |
|          CALL XERBLA( 'ZLATMS', -INFO )
 | |
|          RETURN
 | |
|       END IF
 | |
| *
 | |
| *     Initialize random number generator
 | |
| *
 | |
|       DO 10 I = 1, 4
 | |
|          ISEED( I ) = MOD( ABS( ISEED( I ) ), 4096 )
 | |
|    10 CONTINUE
 | |
| *
 | |
|       IF( MOD( ISEED( 4 ), 2 ).NE.1 )
 | |
|      $   ISEED( 4 ) = ISEED( 4 ) + 1
 | |
| *
 | |
| *     2)      Set up D  if indicated.
 | |
| *
 | |
| *             Compute D according to COND and MODE
 | |
| *
 | |
|       CALL DLATM1( MODE, COND, IRSIGN, IDIST, ISEED, D, MNMIN, IINFO )
 | |
|       IF( IINFO.NE.0 ) THEN
 | |
|          INFO = 1
 | |
|          RETURN
 | |
|       END IF
 | |
| *
 | |
| *     Choose Top-Down if D is (apparently) increasing,
 | |
| *     Bottom-Up if D is (apparently) decreasing.
 | |
| *
 | |
|       IF( ABS( D( 1 ) ).LE.ABS( D( MNMIN ) ) ) THEN
 | |
|          TOPDWN = .TRUE.
 | |
|       ELSE
 | |
|          TOPDWN = .FALSE.
 | |
|       END IF
 | |
| *
 | |
|       IF( MODE.NE.0 .AND. ABS( MODE ).NE.6 ) THEN
 | |
| *
 | |
| *        Scale by DMAX
 | |
| *
 | |
|          TEMP = ABS( D( 1 ) )
 | |
|          DO 20 I = 2, MNMIN
 | |
|             TEMP = MAX( TEMP, ABS( D( I ) ) )
 | |
|    20    CONTINUE
 | |
| *
 | |
|          IF( TEMP.GT.ZERO ) THEN
 | |
|             ALPHA = DMAX / TEMP
 | |
|          ELSE
 | |
|             INFO = 2
 | |
|             RETURN
 | |
|          END IF
 | |
| *
 | |
|          CALL DSCAL( MNMIN, ALPHA, D, 1 )
 | |
| *
 | |
|       END IF
 | |
| *
 | |
|       CALL ZLASET( 'Full', LDA, N, CZERO, CZERO, A, LDA )
 | |
| *
 | |
| *     3)      Generate Banded Matrix using Givens rotations.
 | |
| *             Also the special case of UUB=LLB=0
 | |
| *
 | |
| *               Compute Addressing constants to cover all
 | |
| *               storage formats.  Whether GE, HE, SY, GB, HB, or SB,
 | |
| *               upper or lower triangle or both,
 | |
| *               the (i,j)-th element is in
 | |
| *               A( i - ISKEW*j + IOFFST, j )
 | |
| *
 | |
|       IF( IPACK.GT.4 ) THEN
 | |
|          ILDA = LDA - 1
 | |
|          ISKEW = 1
 | |
|          IF( IPACK.GT.5 ) THEN
 | |
|             IOFFST = UUB + 1
 | |
|          ELSE
 | |
|             IOFFST = 1
 | |
|          END IF
 | |
|       ELSE
 | |
|          ILDA = LDA
 | |
|          ISKEW = 0
 | |
|          IOFFST = 0
 | |
|       END IF
 | |
| *
 | |
| *     IPACKG is the format that the matrix is generated in. If this is
 | |
| *     different from IPACK, then the matrix must be repacked at the
 | |
| *     end.  It also signals how to compute the norm, for scaling.
 | |
| *
 | |
|       IPACKG = 0
 | |
| *
 | |
| *     Diagonal Matrix -- We are done, unless it
 | |
| *     is to be stored HP/SP/PP/TP (PACK='R' or 'C')
 | |
| *
 | |
|       IF( LLB.EQ.0 .AND. UUB.EQ.0 ) THEN
 | |
|          DO 30 J = 1, MNMIN
 | |
|             A( ( 1-ISKEW )*J+IOFFST, J ) = DCMPLX( D( J ) )
 | |
|    30    CONTINUE
 | |
| *
 | |
|          IF( IPACK.LE.2 .OR. IPACK.GE.5 )
 | |
|      $      IPACKG = IPACK
 | |
| *
 | |
|       ELSE IF( GIVENS ) THEN
 | |
| *
 | |
| *        Check whether to use Givens rotations,
 | |
| *        Householder transformations, or nothing.
 | |
| *
 | |
|          IF( ISYM.EQ.1 ) THEN
 | |
| *
 | |
| *           Non-symmetric -- A = U D V
 | |
| *
 | |
|             IF( IPACK.GT.4 ) THEN
 | |
|                IPACKG = IPACK
 | |
|             ELSE
 | |
|                IPACKG = 0
 | |
|             END IF
 | |
| *
 | |
|             DO 40 J = 1, MNMIN
 | |
|                A( ( 1-ISKEW )*J+IOFFST, J ) = DCMPLX( D( J ) )
 | |
|    40       CONTINUE
 | |
| *
 | |
|             IF( TOPDWN ) THEN
 | |
|                JKL = 0
 | |
|                DO 70 JKU = 1, UUB
 | |
| *
 | |
| *                 Transform from bandwidth JKL, JKU-1 to JKL, JKU
 | |
| *
 | |
| *                 Last row actually rotated is M
 | |
| *                 Last column actually rotated is MIN( M+JKU, N )
 | |
| *
 | |
|                   DO 60 JR = 1, MIN( M+JKU, N ) + JKL - 1
 | |
|                      EXTRA = CZERO
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      ICOL = MAX( 1, JR-JKL )
 | |
|                      IF( JR.LT.M ) THEN
 | |
|                         IL = MIN( N, JR+JKU ) + 1 - ICOL
 | |
|                         CALL ZLAROT( .TRUE., JR.GT.JKL, .FALSE., IL, C,
 | |
|      $                               S, A( JR-ISKEW*ICOL+IOFFST, ICOL ),
 | |
|      $                               ILDA, EXTRA, DUMMY )
 | |
|                      END IF
 | |
| *
 | |
| *                    Chase "EXTRA" back up
 | |
| *
 | |
|                      IR = JR
 | |
|                      IC = ICOL
 | |
|                      DO 50 JCH = JR - JKL, 1, -JKL - JKU
 | |
|                         IF( IR.LT.M ) THEN
 | |
|                            CALL ZLARTG( A( IR+1-ISKEW*( IC+1 )+IOFFST,
 | |
|      $                                  IC+1 ), EXTRA, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = DCONJG( REALC*DUMMY )
 | |
|                            S = DCONJG( -S*DUMMY )
 | |
|                         END IF
 | |
|                         IROW = MAX( 1, JCH-JKU )
 | |
|                         IL = IR + 2 - IROW
 | |
|                         CTEMP = CZERO
 | |
|                         ILTEMP = JCH.GT.JKU
 | |
|                         CALL ZLAROT( .FALSE., ILTEMP, .TRUE., IL, C, S,
 | |
|      $                               A( IROW-ISKEW*IC+IOFFST, IC ),
 | |
|      $                               ILDA, CTEMP, EXTRA )
 | |
|                         IF( ILTEMP ) THEN
 | |
|                            CALL ZLARTG( A( IROW+1-ISKEW*( IC+1 )+IOFFST,
 | |
|      $                                  IC+1 ), CTEMP, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = DCONJG( REALC*DUMMY )
 | |
|                            S = DCONJG( -S*DUMMY )
 | |
| *
 | |
|                            ICOL = MAX( 1, JCH-JKU-JKL )
 | |
|                            IL = IC + 2 - ICOL
 | |
|                            EXTRA = CZERO
 | |
|                            CALL ZLAROT( .TRUE., JCH.GT.JKU+JKL, .TRUE.,
 | |
|      $                                  IL, C, S, A( IROW-ISKEW*ICOL+
 | |
|      $                                  IOFFST, ICOL ), ILDA, EXTRA,
 | |
|      $                                  CTEMP )
 | |
|                            IC = ICOL
 | |
|                            IR = IROW
 | |
|                         END IF
 | |
|    50                CONTINUE
 | |
|    60             CONTINUE
 | |
|    70          CONTINUE
 | |
| *
 | |
|                JKU = UUB
 | |
|                DO 100 JKL = 1, LLB
 | |
| *
 | |
| *                 Transform from bandwidth JKL-1, JKU to JKL, JKU
 | |
| *
 | |
|                   DO 90 JC = 1, MIN( N+JKL, M ) + JKU - 1
 | |
|                      EXTRA = CZERO
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      IROW = MAX( 1, JC-JKU )
 | |
|                      IF( JC.LT.N ) THEN
 | |
|                         IL = MIN( M, JC+JKL ) + 1 - IROW
 | |
|                         CALL ZLAROT( .FALSE., JC.GT.JKU, .FALSE., IL, C,
 | |
|      $                               S, A( IROW-ISKEW*JC+IOFFST, JC ),
 | |
|      $                               ILDA, EXTRA, DUMMY )
 | |
|                      END IF
 | |
| *
 | |
| *                    Chase "EXTRA" back up
 | |
| *
 | |
|                      IC = JC
 | |
|                      IR = IROW
 | |
|                      DO 80 JCH = JC - JKU, 1, -JKL - JKU
 | |
|                         IF( IC.LT.N ) THEN
 | |
|                            CALL ZLARTG( A( IR+1-ISKEW*( IC+1 )+IOFFST,
 | |
|      $                                  IC+1 ), EXTRA, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = DCONJG( REALC*DUMMY )
 | |
|                            S = DCONJG( -S*DUMMY )
 | |
|                         END IF
 | |
|                         ICOL = MAX( 1, JCH-JKL )
 | |
|                         IL = IC + 2 - ICOL
 | |
|                         CTEMP = CZERO
 | |
|                         ILTEMP = JCH.GT.JKL
 | |
|                         CALL ZLAROT( .TRUE., ILTEMP, .TRUE., IL, C, S,
 | |
|      $                               A( IR-ISKEW*ICOL+IOFFST, ICOL ),
 | |
|      $                               ILDA, CTEMP, EXTRA )
 | |
|                         IF( ILTEMP ) THEN
 | |
|                            CALL ZLARTG( A( IR+1-ISKEW*( ICOL+1 )+IOFFST,
 | |
|      $                                  ICOL+1 ), CTEMP, REALC, S,
 | |
|      $                                  DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = DCONJG( REALC*DUMMY )
 | |
|                            S = DCONJG( -S*DUMMY )
 | |
|                            IROW = MAX( 1, JCH-JKL-JKU )
 | |
|                            IL = IR + 2 - IROW
 | |
|                            EXTRA = CZERO
 | |
|                            CALL ZLAROT( .FALSE., JCH.GT.JKL+JKU, .TRUE.,
 | |
|      $                                  IL, C, S, A( IROW-ISKEW*ICOL+
 | |
|      $                                  IOFFST, ICOL ), ILDA, EXTRA,
 | |
|      $                                  CTEMP )
 | |
|                            IC = ICOL
 | |
|                            IR = IROW
 | |
|                         END IF
 | |
|    80                CONTINUE
 | |
|    90             CONTINUE
 | |
|   100          CONTINUE
 | |
| *
 | |
|             ELSE
 | |
| *
 | |
| *              Bottom-Up -- Start at the bottom right.
 | |
| *
 | |
|                JKL = 0
 | |
|                DO 130 JKU = 1, UUB
 | |
| *
 | |
| *                 Transform from bandwidth JKL, JKU-1 to JKL, JKU
 | |
| *
 | |
| *                 First row actually rotated is M
 | |
| *                 First column actually rotated is MIN( M+JKU, N )
 | |
| *
 | |
|                   IENDCH = MIN( M, N+JKL ) - 1
 | |
|                   DO 120 JC = MIN( M+JKU, N ) - 1, 1 - JKL, -1
 | |
|                      EXTRA = CZERO
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      IROW = MAX( 1, JC-JKU+1 )
 | |
|                      IF( JC.GT.0 ) THEN
 | |
|                         IL = MIN( M, JC+JKL+1 ) + 1 - IROW
 | |
|                         CALL ZLAROT( .FALSE., .FALSE., JC+JKL.LT.M, IL,
 | |
|      $                               C, S, A( IROW-ISKEW*JC+IOFFST,
 | |
|      $                               JC ), ILDA, DUMMY, EXTRA )
 | |
|                      END IF
 | |
| *
 | |
| *                    Chase "EXTRA" back down
 | |
| *
 | |
|                      IC = JC
 | |
|                      DO 110 JCH = JC + JKL, IENDCH, JKL + JKU
 | |
|                         ILEXTR = IC.GT.0
 | |
|                         IF( ILEXTR ) THEN
 | |
|                            CALL ZLARTG( A( JCH-ISKEW*IC+IOFFST, IC ),
 | |
|      $                                  EXTRA, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = REALC*DUMMY
 | |
|                            S = S*DUMMY
 | |
|                         END IF
 | |
|                         IC = MAX( 1, IC )
 | |
|                         ICOL = MIN( N-1, JCH+JKU )
 | |
|                         ILTEMP = JCH + JKU.LT.N
 | |
|                         CTEMP = CZERO
 | |
|                         CALL ZLAROT( .TRUE., ILEXTR, ILTEMP, ICOL+2-IC,
 | |
|      $                               C, S, A( JCH-ISKEW*IC+IOFFST, IC ),
 | |
|      $                               ILDA, EXTRA, CTEMP )
 | |
|                         IF( ILTEMP ) THEN
 | |
|                            CALL ZLARTG( A( JCH-ISKEW*ICOL+IOFFST,
 | |
|      $                                  ICOL ), CTEMP, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = REALC*DUMMY
 | |
|                            S = S*DUMMY
 | |
|                            IL = MIN( IENDCH, JCH+JKL+JKU ) + 2 - JCH
 | |
|                            EXTRA = CZERO
 | |
|                            CALL ZLAROT( .FALSE., .TRUE.,
 | |
|      $                                  JCH+JKL+JKU.LE.IENDCH, IL, C, S,
 | |
|      $                                  A( JCH-ISKEW*ICOL+IOFFST,
 | |
|      $                                  ICOL ), ILDA, CTEMP, EXTRA )
 | |
|                            IC = ICOL
 | |
|                         END IF
 | |
|   110                CONTINUE
 | |
|   120             CONTINUE
 | |
|   130          CONTINUE
 | |
| *
 | |
|                JKU = UUB
 | |
|                DO 160 JKL = 1, LLB
 | |
| *
 | |
| *                 Transform from bandwidth JKL-1, JKU to JKL, JKU
 | |
| *
 | |
| *                 First row actually rotated is MIN( N+JKL, M )
 | |
| *                 First column actually rotated is N
 | |
| *
 | |
|                   IENDCH = MIN( N, M+JKU ) - 1
 | |
|                   DO 150 JR = MIN( N+JKL, M ) - 1, 1 - JKU, -1
 | |
|                      EXTRA = CZERO
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      ICOL = MAX( 1, JR-JKL+1 )
 | |
|                      IF( JR.GT.0 ) THEN
 | |
|                         IL = MIN( N, JR+JKU+1 ) + 1 - ICOL
 | |
|                         CALL ZLAROT( .TRUE., .FALSE., JR+JKU.LT.N, IL,
 | |
|      $                               C, S, A( JR-ISKEW*ICOL+IOFFST,
 | |
|      $                               ICOL ), ILDA, DUMMY, EXTRA )
 | |
|                      END IF
 | |
| *
 | |
| *                    Chase "EXTRA" back down
 | |
| *
 | |
|                      IR = JR
 | |
|                      DO 140 JCH = JR + JKU, IENDCH, JKL + JKU
 | |
|                         ILEXTR = IR.GT.0
 | |
|                         IF( ILEXTR ) THEN
 | |
|                            CALL ZLARTG( A( IR-ISKEW*JCH+IOFFST, JCH ),
 | |
|      $                                  EXTRA, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = REALC*DUMMY
 | |
|                            S = S*DUMMY
 | |
|                         END IF
 | |
|                         IR = MAX( 1, IR )
 | |
|                         IROW = MIN( M-1, JCH+JKL )
 | |
|                         ILTEMP = JCH + JKL.LT.M
 | |
|                         CTEMP = CZERO
 | |
|                         CALL ZLAROT( .FALSE., ILEXTR, ILTEMP, IROW+2-IR,
 | |
|      $                               C, S, A( IR-ISKEW*JCH+IOFFST,
 | |
|      $                               JCH ), ILDA, EXTRA, CTEMP )
 | |
|                         IF( ILTEMP ) THEN
 | |
|                            CALL ZLARTG( A( IROW-ISKEW*JCH+IOFFST, JCH ),
 | |
|      $                                  CTEMP, REALC, S, DUMMY )
 | |
|                            DUMMY = ZLARND( 5, ISEED )
 | |
|                            C = REALC*DUMMY
 | |
|                            S = S*DUMMY
 | |
|                            IL = MIN( IENDCH, JCH+JKL+JKU ) + 2 - JCH
 | |
|                            EXTRA = CZERO
 | |
|                            CALL ZLAROT( .TRUE., .TRUE.,
 | |
|      $                                  JCH+JKL+JKU.LE.IENDCH, IL, C, S,
 | |
|      $                                  A( IROW-ISKEW*JCH+IOFFST, JCH ),
 | |
|      $                                  ILDA, CTEMP, EXTRA )
 | |
|                            IR = IROW
 | |
|                         END IF
 | |
|   140                CONTINUE
 | |
|   150             CONTINUE
 | |
|   160          CONTINUE
 | |
| *
 | |
|             END IF
 | |
| *
 | |
|          ELSE
 | |
| *
 | |
| *           Symmetric -- A = U D U'
 | |
| *           Hermitian -- A = U D U*
 | |
| *
 | |
|             IPACKG = IPACK
 | |
|             IOFFG = IOFFST
 | |
| *
 | |
|             IF( TOPDWN ) THEN
 | |
| *
 | |
| *              Top-Down -- Generate Upper triangle only
 | |
| *
 | |
|                IF( IPACK.GE.5 ) THEN
 | |
|                   IPACKG = 6
 | |
|                   IOFFG = UUB + 1
 | |
|                ELSE
 | |
|                   IPACKG = 1
 | |
|                END IF
 | |
| *
 | |
|                DO 170 J = 1, MNMIN
 | |
|                   A( ( 1-ISKEW )*J+IOFFG, J ) = DCMPLX( D( J ) )
 | |
|   170          CONTINUE
 | |
| *
 | |
|                DO 200 K = 1, UUB
 | |
|                   DO 190 JC = 1, N - 1
 | |
|                      IROW = MAX( 1, JC-K )
 | |
|                      IL = MIN( JC+1, K+2 )
 | |
|                      EXTRA = CZERO
 | |
|                      CTEMP = A( JC-ISKEW*( JC+1 )+IOFFG, JC+1 )
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      IF( ZSYM ) THEN
 | |
|                         CT = C
 | |
|                         ST = S
 | |
|                      ELSE
 | |
|                         CTEMP = DCONJG( CTEMP )
 | |
|                         CT = DCONJG( C )
 | |
|                         ST = DCONJG( S )
 | |
|                      END IF
 | |
|                      CALL ZLAROT( .FALSE., JC.GT.K, .TRUE., IL, C, S,
 | |
|      $                            A( IROW-ISKEW*JC+IOFFG, JC ), ILDA,
 | |
|      $                            EXTRA, CTEMP )
 | |
|                      CALL ZLAROT( .TRUE., .TRUE., .FALSE.,
 | |
|      $                            MIN( K, N-JC )+1, CT, ST,
 | |
|      $                            A( ( 1-ISKEW )*JC+IOFFG, JC ), ILDA,
 | |
|      $                            CTEMP, DUMMY )
 | |
| *
 | |
| *                    Chase EXTRA back up the matrix
 | |
| *
 | |
|                      ICOL = JC
 | |
|                      DO 180 JCH = JC - K, 1, -K
 | |
|                         CALL ZLARTG( A( JCH+1-ISKEW*( ICOL+1 )+IOFFG,
 | |
|      $                               ICOL+1 ), EXTRA, REALC, S, DUMMY )
 | |
|                         DUMMY = ZLARND( 5, ISEED )
 | |
|                         C = DCONJG( REALC*DUMMY )
 | |
|                         S = DCONJG( -S*DUMMY )
 | |
|                         CTEMP = A( JCH-ISKEW*( JCH+1 )+IOFFG, JCH+1 )
 | |
|                         IF( ZSYM ) THEN
 | |
|                            CT = C
 | |
|                            ST = S
 | |
|                         ELSE
 | |
|                            CTEMP = DCONJG( CTEMP )
 | |
|                            CT = DCONJG( C )
 | |
|                            ST = DCONJG( S )
 | |
|                         END IF
 | |
|                         CALL ZLAROT( .TRUE., .TRUE., .TRUE., K+2, C, S,
 | |
|      $                               A( ( 1-ISKEW )*JCH+IOFFG, JCH ),
 | |
|      $                               ILDA, CTEMP, EXTRA )
 | |
|                         IROW = MAX( 1, JCH-K )
 | |
|                         IL = MIN( JCH+1, K+2 )
 | |
|                         EXTRA = CZERO
 | |
|                         CALL ZLAROT( .FALSE., JCH.GT.K, .TRUE., IL, CT,
 | |
|      $                               ST, A( IROW-ISKEW*JCH+IOFFG, JCH ),
 | |
|      $                               ILDA, EXTRA, CTEMP )
 | |
|                         ICOL = JCH
 | |
|   180                CONTINUE
 | |
|   190             CONTINUE
 | |
|   200          CONTINUE
 | |
| *
 | |
| *              If we need lower triangle, copy from upper. Note that
 | |
| *              the order of copying is chosen to work for 'q' -> 'b'
 | |
| *
 | |
|                IF( IPACK.NE.IPACKG .AND. IPACK.NE.3 ) THEN
 | |
|                   DO 230 JC = 1, N
 | |
|                      IROW = IOFFST - ISKEW*JC
 | |
|                      IF( ZSYM ) THEN
 | |
|                         DO 210 JR = JC, MIN( N, JC+UUB )
 | |
|                            A( JR+IROW, JC ) = A( JC-ISKEW*JR+IOFFG, JR )
 | |
|   210                   CONTINUE
 | |
|                      ELSE
 | |
|                         DO 220 JR = JC, MIN( N, JC+UUB )
 | |
|                            A( JR+IROW, JC ) = DCONJG( A( JC-ISKEW*JR+
 | |
|      $                                        IOFFG, JR ) )
 | |
|   220                   CONTINUE
 | |
|                      END IF
 | |
|   230             CONTINUE
 | |
|                   IF( IPACK.EQ.5 ) THEN
 | |
|                      DO 250 JC = N - UUB + 1, N
 | |
|                         DO 240 JR = N + 2 - JC, UUB + 1
 | |
|                            A( JR, JC ) = CZERO
 | |
|   240                   CONTINUE
 | |
|   250                CONTINUE
 | |
|                   END IF
 | |
|                   IF( IPACKG.EQ.6 ) THEN
 | |
|                      IPACKG = IPACK
 | |
|                   ELSE
 | |
|                      IPACKG = 0
 | |
|                   END IF
 | |
|                END IF
 | |
|             ELSE
 | |
| *
 | |
| *              Bottom-Up -- Generate Lower triangle only
 | |
| *
 | |
|                IF( IPACK.GE.5 ) THEN
 | |
|                   IPACKG = 5
 | |
|                   IF( IPACK.EQ.6 )
 | |
|      $               IOFFG = 1
 | |
|                ELSE
 | |
|                   IPACKG = 2
 | |
|                END IF
 | |
| *
 | |
|                DO 260 J = 1, MNMIN
 | |
|                   A( ( 1-ISKEW )*J+IOFFG, J ) = DCMPLX( D( J ) )
 | |
|   260          CONTINUE
 | |
| *
 | |
|                DO 290 K = 1, UUB
 | |
|                   DO 280 JC = N - 1, 1, -1
 | |
|                      IL = MIN( N+1-JC, K+2 )
 | |
|                      EXTRA = CZERO
 | |
|                      CTEMP = A( 1+( 1-ISKEW )*JC+IOFFG, JC )
 | |
|                      ANGLE = TWOPI*DLARND( 1, ISEED )
 | |
|                      C = COS( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      S = SIN( ANGLE )*ZLARND( 5, ISEED )
 | |
|                      IF( ZSYM ) THEN
 | |
|                         CT = C
 | |
|                         ST = S
 | |
|                      ELSE
 | |
|                         CTEMP = DCONJG( CTEMP )
 | |
|                         CT = DCONJG( C )
 | |
|                         ST = DCONJG( S )
 | |
|                      END IF
 | |
|                      CALL ZLAROT( .FALSE., .TRUE., N-JC.GT.K, IL, C, S,
 | |
|      $                            A( ( 1-ISKEW )*JC+IOFFG, JC ), ILDA,
 | |
|      $                            CTEMP, EXTRA )
 | |
|                      ICOL = MAX( 1, JC-K+1 )
 | |
|                      CALL ZLAROT( .TRUE., .FALSE., .TRUE., JC+2-ICOL,
 | |
|      $                            CT, ST, A( JC-ISKEW*ICOL+IOFFG,
 | |
|      $                            ICOL ), ILDA, DUMMY, CTEMP )
 | |
| *
 | |
| *                    Chase EXTRA back down the matrix
 | |
| *
 | |
|                      ICOL = JC
 | |
|                      DO 270 JCH = JC + K, N - 1, K
 | |
|                         CALL ZLARTG( A( JCH-ISKEW*ICOL+IOFFG, ICOL ),
 | |
|      $                               EXTRA, REALC, S, DUMMY )
 | |
|                         DUMMY = ZLARND( 5, ISEED )
 | |
|                         C = REALC*DUMMY
 | |
|                         S = S*DUMMY
 | |
|                         CTEMP = A( 1+( 1-ISKEW )*JCH+IOFFG, JCH )
 | |
|                         IF( ZSYM ) THEN
 | |
|                            CT = C
 | |
|                            ST = S
 | |
|                         ELSE
 | |
|                            CTEMP = DCONJG( CTEMP )
 | |
|                            CT = DCONJG( C )
 | |
|                            ST = DCONJG( S )
 | |
|                         END IF
 | |
|                         CALL ZLAROT( .TRUE., .TRUE., .TRUE., K+2, C, S,
 | |
|      $                               A( JCH-ISKEW*ICOL+IOFFG, ICOL ),
 | |
|      $                               ILDA, EXTRA, CTEMP )
 | |
|                         IL = MIN( N+1-JCH, K+2 )
 | |
|                         EXTRA = CZERO
 | |
|                         CALL ZLAROT( .FALSE., .TRUE., N-JCH.GT.K, IL,
 | |
|      $                               CT, ST, A( ( 1-ISKEW )*JCH+IOFFG,
 | |
|      $                               JCH ), ILDA, CTEMP, EXTRA )
 | |
|                         ICOL = JCH
 | |
|   270                CONTINUE
 | |
|   280             CONTINUE
 | |
|   290          CONTINUE
 | |
| *
 | |
| *              If we need upper triangle, copy from lower. Note that
 | |
| *              the order of copying is chosen to work for 'b' -> 'q'
 | |
| *
 | |
|                IF( IPACK.NE.IPACKG .AND. IPACK.NE.4 ) THEN
 | |
|                   DO 320 JC = N, 1, -1
 | |
|                      IROW = IOFFST - ISKEW*JC
 | |
|                      IF( ZSYM ) THEN
 | |
|                         DO 300 JR = JC, MAX( 1, JC-UUB ), -1
 | |
|                            A( JR+IROW, JC ) = A( JC-ISKEW*JR+IOFFG, JR )
 | |
|   300                   CONTINUE
 | |
|                      ELSE
 | |
|                         DO 310 JR = JC, MAX( 1, JC-UUB ), -1
 | |
|                            A( JR+IROW, JC ) = DCONJG( A( JC-ISKEW*JR+
 | |
|      $                                        IOFFG, JR ) )
 | |
|   310                   CONTINUE
 | |
|                      END IF
 | |
|   320             CONTINUE
 | |
|                   IF( IPACK.EQ.6 ) THEN
 | |
|                      DO 340 JC = 1, UUB
 | |
|                         DO 330 JR = 1, UUB + 1 - JC
 | |
|                            A( JR, JC ) = CZERO
 | |
|   330                   CONTINUE
 | |
|   340                CONTINUE
 | |
|                   END IF
 | |
|                   IF( IPACKG.EQ.5 ) THEN
 | |
|                      IPACKG = IPACK
 | |
|                   ELSE
 | |
|                      IPACKG = 0
 | |
|                   END IF
 | |
|                END IF
 | |
|             END IF
 | |
| *
 | |
| *           Ensure that the diagonal is real if Hermitian
 | |
| *
 | |
|             IF( .NOT.ZSYM ) THEN
 | |
|                DO 350 JC = 1, N
 | |
|                   IROW = IOFFST + ( 1-ISKEW )*JC
 | |
|                   A( IROW, JC ) = DCMPLX( DBLE( A( IROW, JC ) ) )
 | |
|   350          CONTINUE
 | |
|             END IF
 | |
| *
 | |
|          END IF
 | |
| *
 | |
|       ELSE
 | |
| *
 | |
| *        4)      Generate Banded Matrix by first
 | |
| *                Rotating by random Unitary matrices,
 | |
| *                then reducing the bandwidth using Householder
 | |
| *                transformations.
 | |
| *
 | |
| *                Note: we should get here only if LDA .ge. N
 | |
| *
 | |
|          IF( ISYM.EQ.1 ) THEN
 | |
| *
 | |
| *           Non-symmetric -- A = U D V
 | |
| *
 | |
|             CALL ZLAGGE( MR, NC, LLB, UUB, D, A, LDA, ISEED, WORK,
 | |
|      $                   IINFO )
 | |
|          ELSE
 | |
| *
 | |
| *           Symmetric -- A = U D U' or
 | |
| *           Hermitian -- A = U D U*
 | |
| *
 | |
|             IF( ZSYM ) THEN
 | |
|                CALL ZLAGSY( M, LLB, D, A, LDA, ISEED, WORK, IINFO )
 | |
|             ELSE
 | |
|                CALL ZLAGHE( M, LLB, D, A, LDA, ISEED, WORK, IINFO )
 | |
|             END IF
 | |
|          END IF
 | |
| *
 | |
|          IF( IINFO.NE.0 ) THEN
 | |
|             INFO = 3
 | |
|             RETURN
 | |
|          END IF
 | |
|       END IF
 | |
| *
 | |
| *     5)      Pack the matrix
 | |
| *
 | |
|       IF( IPACK.NE.IPACKG ) THEN
 | |
|          IF( IPACK.EQ.1 ) THEN
 | |
| *
 | |
| *           'U' -- Upper triangular, not packed
 | |
| *
 | |
|             DO 370 J = 1, M
 | |
|                DO 360 I = J + 1, M
 | |
|                   A( I, J ) = CZERO
 | |
|   360          CONTINUE
 | |
|   370       CONTINUE
 | |
| *
 | |
|          ELSE IF( IPACK.EQ.2 ) THEN
 | |
| *
 | |
| *           'L' -- Lower triangular, not packed
 | |
| *
 | |
|             DO 390 J = 2, M
 | |
|                DO 380 I = 1, J - 1
 | |
|                   A( I, J ) = CZERO
 | |
|   380          CONTINUE
 | |
|   390       CONTINUE
 | |
| *
 | |
|          ELSE IF( IPACK.EQ.3 ) THEN
 | |
| *
 | |
| *           'C' -- Upper triangle packed Columnwise.
 | |
| *
 | |
|             ICOL = 1
 | |
|             IROW = 0
 | |
|             DO 410 J = 1, M
 | |
|                DO 400 I = 1, J
 | |
|                   IROW = IROW + 1
 | |
|                   IF( IROW.GT.LDA ) THEN
 | |
|                      IROW = 1
 | |
|                      ICOL = ICOL + 1
 | |
|                   END IF
 | |
|                   A( IROW, ICOL ) = A( I, J )
 | |
|   400          CONTINUE
 | |
|   410       CONTINUE
 | |
| *
 | |
|          ELSE IF( IPACK.EQ.4 ) THEN
 | |
| *
 | |
| *           'R' -- Lower triangle packed Columnwise.
 | |
| *
 | |
|             ICOL = 1
 | |
|             IROW = 0
 | |
|             DO 430 J = 1, M
 | |
|                DO 420 I = J, M
 | |
|                   IROW = IROW + 1
 | |
|                   IF( IROW.GT.LDA ) THEN
 | |
|                      IROW = 1
 | |
|                      ICOL = ICOL + 1
 | |
|                   END IF
 | |
|                   A( IROW, ICOL ) = A( I, J )
 | |
|   420          CONTINUE
 | |
|   430       CONTINUE
 | |
| *
 | |
|          ELSE IF( IPACK.GE.5 ) THEN
 | |
| *
 | |
| *           'B' -- The lower triangle is packed as a band matrix.
 | |
| *           'Q' -- The upper triangle is packed as a band matrix.
 | |
| *           'Z' -- The whole matrix is packed as a band matrix.
 | |
| *
 | |
|             IF( IPACK.EQ.5 )
 | |
|      $         UUB = 0
 | |
|             IF( IPACK.EQ.6 )
 | |
|      $         LLB = 0
 | |
| *
 | |
|             DO 450 J = 1, UUB
 | |
|                DO 440 I = MIN( J+LLB, M ), 1, -1
 | |
|                   A( I-J+UUB+1, J ) = A( I, J )
 | |
|   440          CONTINUE
 | |
|   450       CONTINUE
 | |
| *
 | |
|             DO 470 J = UUB + 2, N
 | |
|                DO 460 I = J - UUB, MIN( J+LLB, M )
 | |
|                   A( I-J+UUB+1, J ) = A( I, J )
 | |
|   460          CONTINUE
 | |
|   470       CONTINUE
 | |
|          END IF
 | |
| *
 | |
| *        If packed, zero out extraneous elements.
 | |
| *
 | |
| *        Symmetric/Triangular Packed --
 | |
| *        zero out everything after A(IROW,ICOL)
 | |
| *
 | |
|          IF( IPACK.EQ.3 .OR. IPACK.EQ.4 ) THEN
 | |
|             DO 490 JC = ICOL, M
 | |
|                DO 480 JR = IROW + 1, LDA
 | |
|                   A( JR, JC ) = CZERO
 | |
|   480          CONTINUE
 | |
|                IROW = 0
 | |
|   490       CONTINUE
 | |
| *
 | |
|          ELSE IF( IPACK.GE.5 ) THEN
 | |
| *
 | |
| *           Packed Band --
 | |
| *              1st row is now in A( UUB+2-j, j), zero above it
 | |
| *              m-th row is now in A( M+UUB-j,j), zero below it
 | |
| *              last non-zero diagonal is now in A( UUB+LLB+1,j ),
 | |
| *                 zero below it, too.
 | |
| *
 | |
|             IR1 = UUB + LLB + 2
 | |
|             IR2 = UUB + M + 2
 | |
|             DO 520 JC = 1, N
 | |
|                DO 500 JR = 1, UUB + 1 - JC
 | |
|                   A( JR, JC ) = CZERO
 | |
|   500          CONTINUE
 | |
|                DO 510 JR = MAX( 1, MIN( IR1, IR2-JC ) ), LDA
 | |
|                   A( JR, JC ) = CZERO
 | |
|   510          CONTINUE
 | |
|   520       CONTINUE
 | |
|          END IF
 | |
|       END IF
 | |
| *
 | |
|       RETURN
 | |
| *
 | |
| *     End of ZLATMS
 | |
| *
 | |
|       END
 |