91 REAL FUNCTION stzt02( M, N, AF, LDA, TAU, WORK,
100 INTEGER lda, lwork, m, n
103 REAL af( lda, * ), tau( * ), work( lwork )
110 parameter( zero = 0.0e0, one = 1.0e0 )
132 IF( lwork.LT.n*n+n )
THEN
133 CALL
xerbla(
'STZT02', 7 )
139 IF( m.LE.0 .OR. n.LE.0 )
144 CALL
slaset(
'Full', n, n, zero, one, work, n )
149 CALL
slatzm(
'Left', n-m+1, n, af( i, m+1 ), lda, tau( i ),
150 $ work( i ), work( m+1 ), n, work( n*n+1 ) )
156 CALL
slatzm(
'Left', n-m+1, n, af( i, m+1 ), lda, tau( i ),
157 $ work( i ), work( m+1 ), n, work( n*n+1 ) )
163 work( ( i-1 )*n+i ) = work( ( i-1 )*n+i ) - one
167 $ (
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...
REAL function slamch(CMACH)
SLAMCH
subroutine xerbla(SRNAME, INFO)
XERBLA
REAL function slange(NORM, M, N, A, LDA, WORK)
SLANGE returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value ...
REAL function stzt02(M, N, AF, LDA, TAU, WORK, LWORK)
STZT02
subroutine slatzm(SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK)
SLATZM