126 SUBROUTINE sqrt01p( M, N, A, AF, Q, R, LDA, TAU, WORK, LWORK,
135 INTEGER LDA, LWORK, M, N
138 REAL A( lda, * ), AF( lda, * ), Q( lda, * ),
139 $ r( lda, * ), result( * ), rwork( * ), tau( * ),
147 parameter ( zero = 0.0e+0, one = 1.0e+0 )
149 parameter ( rogue = -1.0e+10 )
153 REAL ANORM, EPS, RESID
156 REAL SLAMCH, SLANGE, SLANSY
157 EXTERNAL slamch, slange, slansy
163 INTRINSIC max, min, real
169 COMMON / srnamc / srnamt
174 eps = slamch(
'Epsilon' )
178 CALL slacpy(
'Full', m, n, a, lda, af, lda )
183 CALL sgeqrfp( m, n, af, lda, tau, work, lwork, info )
187 CALL slaset(
'Full', m, m, rogue, rogue, q, lda )
188 CALL slacpy(
'Lower', m-1, n, af( 2, 1 ), lda, q( 2, 1 ), lda )
193 CALL sorgqr( m, m, minmn, q, lda, tau, work, lwork, info )
197 CALL slaset(
'Full', m, n, zero, zero, r, lda )
198 CALL slacpy(
'Upper', m, n, af, lda, r, lda )
202 CALL sgemm(
'Transpose',
'No transpose', m, n, m, -one, q, lda, a,
207 anorm = slange(
'1', m, n, a, lda, rwork )
208 resid = slange(
'1', m, n, r, lda, rwork )
209 IF( anorm.GT.zero )
THEN
210 result( 1 ) = ( ( resid /
REAL( MAX( 1, M ) ) ) / anorm ) / eps
217 CALL slaset(
'Full', m, m, zero, one, r, lda )
218 CALL ssyrk(
'Upper',
'Transpose', m, m, -one, q, lda, one, r,
223 resid = slansy(
'1',
'Upper', m, r, lda, rwork )
225 result( 2 ) = ( resid /
REAL( MAX( 1, M ) ) ) / eps
subroutine sgeqrfp(M, N, A, LDA, TAU, WORK, LWORK, INFO)
SGEQRFP
subroutine ssyrk(UPLO, TRANS, N, K, ALPHA, A, LDA, BETA, C, LDC)
SSYRK
subroutine sgemm(TRANSA, TRANSB, M, N, K, ALPHA, A, LDA, B, LDB, BETA, C, LDC)
SGEMM
subroutine slaset(UPLO, M, N, ALPHA, BETA, A, LDA)
SLASET initializes the off-diagonal elements and the diagonal elements of a matrix to given values...
subroutine sorgqr(M, N, K, A, LDA, TAU, WORK, LWORK, INFO)
SORGQR
subroutine sqrt01p(M, N, A, AF, Q, R, LDA, TAU, WORK, LWORK, RWORK, RESULT)
SQRT01P
subroutine slacpy(UPLO, M, N, A, LDA, B, LDB)
SLACPY copies all or part of one two-dimensional array to another.