92 SUBROUTINE zpptri( UPLO, N, AP, INFO )
110 parameter( one = 1.0d+0 )
114 INTEGER J, JC, JJ, JJN
120 EXTERNAL lsame, zdotc
133 upper = lsame( uplo,
'U' )
134 IF( .NOT.upper .AND. .NOT.lsame( uplo,
'L' ) )
THEN
136 ELSE IF( n.LT.0 )
THEN
140 CALL xerbla(
'ZPPTRI', -info )
151 CALL ztptri( uplo,
'Non-unit', n, ap, info )
163 $
CALL zhpr(
'Upper', j-1, one, ap( jc ), 1, ap )
164 ajj = dble( ap( jj ) )
165 CALL zdscal( j, ajj, ap( jc ), 1 )
175 ap( jj ) = dble( zdotc( n-j+1, ap( jj ), 1, ap( jj ), 1 ) )
177 $
CALL ztpmv(
'Lower',
'Conjugate transpose',
'Non-unit',
178 $ n-j, ap( jjn ), ap( jj+1 ), 1 )
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine zdscal(N, DA, ZX, INCX)
ZDSCAL
subroutine zhpr(UPLO, N, ALPHA, X, INCX, AP)
ZHPR
subroutine ztpmv(UPLO, TRANS, DIAG, N, AP, X, INCX)
ZTPMV
subroutine ztptri(UPLO, DIAG, N, AP, INFO)
ZTPTRI
subroutine zpptri(UPLO, N, AP, INFO)
ZPPTRI