116 SUBROUTINE ztptri( UPLO, DIAG, N, AP, INFO )
134 parameter( one = ( 1.0d+0, 0.0d+0 ),
135 $ zero = ( 0.0d+0, 0.0d+0 ) )
138 LOGICAL NOUNIT, UPPER
139 INTEGER J, JC, JCLAST, JJ
154 upper = lsame( uplo,
'U' )
155 nounit = lsame( diag,
'N' )
156 IF( .NOT.upper .AND. .NOT.lsame( uplo,
'L' ) )
THEN
158 ELSE IF( .NOT.nounit .AND. .NOT.lsame( diag,
'U' ) )
THEN
160 ELSE IF( n.LT.0 )
THEN
164 CALL xerbla(
'ZTPTRI', -info )
175 IF( ap( jj ).EQ.zero )
181 IF( ap( jj ).EQ.zero )
183 jj = jj + n - info + 1
196 ap( jc+j-1 ) = one / ap( jc+j-1 )
204 CALL ztpmv(
'Upper',
'No transpose', diag, j-1, ap,
206 CALL zscal( j-1, ajj, ap( jc ), 1 )
217 ap( jc ) = one / ap( jc )
226 CALL ztpmv(
'Lower',
'No transpose', diag, n-j,
227 $ ap( jclast ), ap( jc+1 ), 1 )
228 CALL zscal( n-j, ajj, ap( jc+1 ), 1 )
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine zscal(N, ZA, ZX, INCX)
ZSCAL
subroutine ztpmv(UPLO, TRANS, DIAG, N, AP, X, INCX)
ZTPMV
subroutine ztptri(UPLO, DIAG, N, AP, INFO)
ZTPTRI