146 SUBROUTINE sgtcon( NORM, N, DL, D, DU, DU2, IPIV, ANORM, RCOND,
147 $ work, iwork, info )
160 INTEGER IPIV( * ), IWORK( * )
161 REAL D( * ), DL( * ), DU( * ), DU2( * ), WORK( * )
168 parameter( one = 1.0e+0, zero = 0.0e+0 )
172 INTEGER I, KASE, KASE1
190 onenrm = norm.EQ.
'1' .OR. lsame( norm,
'O' )
191 IF( .NOT.onenrm .AND. .NOT.lsame( norm,
'I' ) )
THEN
193 ELSE IF( n.LT.0 )
THEN
195 ELSE IF( anorm.LT.zero )
THEN
199 CALL
xerbla(
'SGTCON', -info )
209 ELSE IF( anorm.EQ.zero )
THEN
228 CALL
slacn2( n, work( n+1 ), work, iwork, ainvnm, kase, isave )
230 IF( kase.EQ.kase1 )
THEN
234 CALL
sgttrs(
'No transpose', n, 1, dl, d, du, du2, ipiv,
240 CALL
sgttrs(
'Transpose', n, 1, dl, d, du, du2, ipiv, work,
249 $ rcond = ( one / ainvnm ) / anorm
subroutine sgtcon(NORM, N, DL, D, DU, DU2, IPIV, ANORM, RCOND, WORK, IWORK, INFO)
SGTCON
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine sgttrs(TRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB, INFO)
SGTTRS
subroutine slacn2(N, V, X, ISGN, EST, KASE, ISAVE)
SLACN2 estimates the 1-norm of a square matrix, using reverse communication for evaluating matrix-vec...