98 REAL FUNCTION stzt01( M, N, A, AF, LDA, TAU, WORK,
107 INTEGER LDA, LWORK, M, N
110 REAL A( lda, * ), AF( lda, * ), TAU( * ),
118 parameter( zero = 0.0e0, one = 1.0e0 )
129 EXTERNAL slamch, slange
141 IF( lwork.LT.m*n+m )
THEN
142 CALL xerbla(
'STZT01', 8 )
148 IF( m.LE.0 .OR. n.LE.0 )
151 norma = slange(
'One-norm', m, n, a, lda, rwork )
155 CALL slaset(
'Full', m, n, zero, zero, work, m )
158 work( ( j-1 )*m+i ) = af( i, j )
165 CALL slatzm(
'Right', i, n-m+1, af( i, m+1 ), lda, tau( i ),
166 $ work( ( i-1 )*m+1 ), work( m*m+1 ), m,
173 CALL saxpy( m, -one, a( 1, i ), 1, work( ( i-1 )*m+1 ), 1 )
176 stzt01 = slange(
'One-norm', m, n, work, m, rwork )
178 stzt01 =
stzt01 / ( slamch(
'Epsilon' )*
REAL( MAX( M, N ) ) )
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 xerbla(SRNAME, INFO)
XERBLA
subroutine saxpy(N, SA, SX, INCX, SY, INCY)
SAXPY
real function stzt01(M, N, A, AF, LDA, TAU, WORK, LWORK)
STZT01
subroutine slatzm(SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK)
SLATZM