115 SUBROUTINE dorg2r( M, N, K, A, LDA, TAU, WORK, INFO )
123 INTEGER INFO, K, LDA, M, N
126 DOUBLE PRECISION A( lda, * ), TAU( * ), WORK( * )
132 DOUBLE PRECISION ONE, ZERO
133 parameter ( one = 1.0d+0, zero = 0.0d+0 )
151 ELSE IF( n.LT.0 .OR. n.GT.m )
THEN
153 ELSE IF( k.LT.0 .OR. k.GT.n )
THEN
155 ELSE IF( lda.LT.max( 1, m ) )
THEN
159 CALL xerbla(
'DORG2R', -info )
183 CALL dlarf(
'Left', m-i+1, n-i, a( i, i ), 1, tau( i ),
184 $ a( i, i+1 ), lda, work )
187 $
CALL dscal( m-i, -tau( i ), a( i+1, i ), 1 )
188 a( i, i ) = one - tau( i )
subroutine dlarf(SIDE, M, N, V, INCV, TAU, C, LDC, WORK)
DLARF applies an elementary reflector to a general rectangular matrix.
subroutine dorg2r(M, N, K, A, LDA, TAU, WORK, INFO)
DORG2R generates all or part of the orthogonal matrix Q from a QR factorization determined by sgeqrf ...
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine dscal(N, DA, DX, INCX)
DSCAL