121 SUBROUTINE dgeqrs( M, N, NRHS, A, LDA, TAU, B, LDB, WORK, LWORK,
130 INTEGER info, lda, ldb, lwork, m, n, nrhs
133 DOUBLE PRECISION a( lda, * ),
b( ldb, * ), tau( * ),
141 parameter( one = 1.0d+0 )
156 ELSE IF( n.LT.0 .OR. n.GT.m )
THEN
158 ELSE IF( nrhs.LT.0 )
THEN
160 ELSE IF( lda.LT.max( 1, m ) )
THEN
162 ELSE IF( ldb.LT.max( 1, m ) )
THEN
164 ELSE IF( lwork.LT.1 .OR. lwork.LT.nrhs .AND. m.GT.0 .AND. n.GT.0 )
169 CALL
xerbla(
'DGEQRS', -info )
175 IF( n.EQ.0 .OR. nrhs.EQ.0 .OR. m.EQ.0 )
180 CALL
dormqr(
'Left',
'Transpose', m, nrhs, n, a, lda, tau,
b, ldb,
181 $ work, lwork, info )
185 CALL
dtrsm(
'Left',
'Upper',
'No transpose',
'Non-unit', n, nrhs,
186 $ one, a, lda,
b, ldb )
subroutine dormqr(SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, LWORK, INFO)
DORMQR
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine dgeqrs(M, N, NRHS, A, LDA, TAU, B, LDB, WORK, LWORK, INFO)
DGEQRS
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real b(3) integer i
subroutine dtrsm(SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA, B, LDB)
DTRSM