1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247
|
*> \brief \b CRQT02
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* SUBROUTINE CRQT02( M, N, K, A, AF, Q, R, LDA, TAU, WORK, LWORK,
* RWORK, RESULT )
*
* .. Scalar Arguments ..
* INTEGER K, LDA, LWORK, M, N
* ..
* .. Array Arguments ..
* REAL RESULT( * ), RWORK( * )
* COMPLEX A( LDA, * ), AF( LDA, * ), Q( LDA, * ),
* $ R( LDA, * ), TAU( * ), WORK( LWORK )
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> CRQT02 tests CUNGRQ, which generates an m-by-n matrix Q with
*> orthonornmal rows that is defined as the product of k elementary
*> reflectors.
*>
*> Given the RQ factorization of an m-by-n matrix A, CRQT02 generates
*> the orthogonal matrix Q defined by the factorization of the last k
*> rows of A; it compares R(m-k+1:m,n-m+1:n) with
*> A(m-k+1:m,1:n)*Q(n-m+1:n,1:n)', and checks that the rows of Q are
*> orthonormal.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] M
*> \verbatim
*> M is INTEGER
*> The number of rows of the matrix Q to be generated. M >= 0.
*> \endverbatim
*>
*> \param[in] N
*> \verbatim
*> N is INTEGER
*> The number of columns of the matrix Q to be generated.
*> N >= M >= 0.
*> \endverbatim
*>
*> \param[in] K
*> \verbatim
*> K is INTEGER
*> The number of elementary reflectors whose product defines the
*> matrix Q. M >= K >= 0.
*> \endverbatim
*>
*> \param[in] A
*> \verbatim
*> A is COMPLEX array, dimension (LDA,N)
*> The m-by-n matrix A which was factorized by CRQT01.
*> \endverbatim
*>
*> \param[in] AF
*> \verbatim
*> AF is COMPLEX array, dimension (LDA,N)
*> Details of the RQ factorization of A, as returned by CGERQF.
*> See CGERQF for further details.
*> \endverbatim
*>
*> \param[out] Q
*> \verbatim
*> Q is COMPLEX array, dimension (LDA,N)
*> \endverbatim
*>
*> \param[out] R
*> \verbatim
*> R is COMPLEX array, dimension (LDA,M)
*> \endverbatim
*>
*> \param[in] LDA
*> \verbatim
*> LDA is INTEGER
*> The leading dimension of the arrays A, AF, Q and L. LDA >= N.
*> \endverbatim
*>
*> \param[in] TAU
*> \verbatim
*> TAU is COMPLEX array, dimension (M)
*> The scalar factors of the elementary reflectors corresponding
*> to the RQ factorization in AF.
*> \endverbatim
*>
*> \param[out] WORK
*> \verbatim
*> WORK is COMPLEX array, dimension (LWORK)
*> \endverbatim
*>
*> \param[in] LWORK
*> \verbatim
*> LWORK is INTEGER
*> The dimension of the array WORK.
*> \endverbatim
*>
*> \param[out] RWORK
*> \verbatim
*> RWORK is REAL array, dimension (M)
*> \endverbatim
*>
*> \param[out] RESULT
*> \verbatim
*> RESULT is REAL array, dimension (2)
*> The test ratios:
*> RESULT(1) = norm( R - A*Q' ) / ( N * norm(A) * EPS )
*> RESULT(2) = norm( I - Q*Q' ) / ( N * EPS )
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date November 2011
*
*> \ingroup complex_lin
*
* =====================================================================
SUBROUTINE CRQT02( M, N, K, A, AF, Q, R, LDA, TAU, WORK, LWORK,
$ RWORK, RESULT )
*
* -- LAPACK test routine (version 3.4.0) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* November 2011
*
* .. Scalar Arguments ..
INTEGER K, LDA, LWORK, M, N
* ..
* .. Array Arguments ..
REAL RESULT( * ), RWORK( * )
COMPLEX A( LDA, * ), AF( LDA, * ), Q( LDA, * ),
$ R( LDA, * ), TAU( * ), WORK( LWORK )
* ..
*
* =====================================================================
*
* .. Parameters ..
REAL ZERO, ONE
PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
COMPLEX ROGUE
PARAMETER ( ROGUE = ( -1.0E+10, -1.0E+10 ) )
* ..
* .. Local Scalars ..
INTEGER INFO
REAL ANORM, EPS, RESID
* ..
* .. External Functions ..
REAL CLANGE, CLANSY, SLAMCH
EXTERNAL CLANGE, CLANSY, SLAMCH
* ..
* .. External Subroutines ..
EXTERNAL CGEMM, CHERK, CLACPY, CLASET, CUNGRQ
* ..
* .. Intrinsic Functions ..
INTRINSIC CMPLX, MAX, REAL
* ..
* .. Scalars in Common ..
CHARACTER*32 SRNAMT
* ..
* .. Common blocks ..
COMMON / SRNAMC / SRNAMT
* ..
* .. Executable Statements ..
*
* Quick return if possible
*
IF( M.EQ.0 .OR. N.EQ.0 .OR. K.EQ.0 ) THEN
RESULT( 1 ) = ZERO
RESULT( 2 ) = ZERO
RETURN
END IF
*
EPS = SLAMCH( 'Epsilon' )
*
* Copy the last k rows of the factorization to the array Q
*
CALL CLASET( 'Full', M, N, ROGUE, ROGUE, Q, LDA )
IF( K.LT.N )
$ CALL CLACPY( 'Full', K, N-K, AF( M-K+1, 1 ), LDA,
$ Q( M-K+1, 1 ), LDA )
IF( K.GT.1 )
$ CALL CLACPY( 'Lower', K-1, K-1, AF( M-K+2, N-K+1 ), LDA,
$ Q( M-K+2, N-K+1 ), LDA )
*
* Generate the last n rows of the matrix Q
*
SRNAMT = 'CUNGRQ'
CALL CUNGRQ( M, N, K, Q, LDA, TAU( M-K+1 ), WORK, LWORK, INFO )
*
* Copy R(m-k+1:m,n-m+1:n)
*
CALL CLASET( 'Full', K, M, CMPLX( ZERO ), CMPLX( ZERO ),
$ R( M-K+1, N-M+1 ), LDA )
CALL CLACPY( 'Upper', K, K, AF( M-K+1, N-K+1 ), LDA,
$ R( M-K+1, N-K+1 ), LDA )
*
* Compute R(m-k+1:m,n-m+1:n) - A(m-k+1:m,1:n) * Q(n-m+1:n,1:n)'
*
CALL CGEMM( 'No transpose', 'Conjugate transpose', K, M, N,
$ CMPLX( -ONE ), A( M-K+1, 1 ), LDA, Q, LDA,
$ CMPLX( ONE ), R( M-K+1, N-M+1 ), LDA )
*
* Compute norm( R - A*Q' ) / ( N * norm(A) * EPS ) .
*
ANORM = CLANGE( '1', K, N, A( M-K+1, 1 ), LDA, RWORK )
RESID = CLANGE( '1', K, M, R( M-K+1, N-M+1 ), LDA, RWORK )
IF( ANORM.GT.ZERO ) THEN
RESULT( 1 ) = ( ( RESID / REAL( MAX( 1, N ) ) ) / ANORM ) / EPS
ELSE
RESULT( 1 ) = ZERO
END IF
*
* Compute I - Q*Q'
*
CALL CLASET( 'Full', M, M, CMPLX( ZERO ), CMPLX( ONE ), R, LDA )
CALL CHERK( 'Upper', 'No transpose', M, N, -ONE, Q, LDA, ONE, R,
$ LDA )
*
* Compute norm( I - Q*Q' ) / ( N * EPS ) .
*
RESID = CLANSY( '1', 'Upper', M, R, LDA, RWORK )
*
RESULT( 2 ) = ( RESID / REAL( MAX( 1, N ) ) ) / EPS
*
RETURN
*
* End of CRQT02
*
END
|