redhat man page for zpptri

ZPPTRI(l)								 )								 ZPPTRI(l)

NAME
       ZPPTRI  -  compute  the inverse of a complex Hermitian positive definite matrix A using the Cholesky factorization A = U**H*U or A = L*L**H
       computed by ZPPTRF

SYNOPSIS
       SUBROUTINE ZPPTRI( UPLO, N, AP, INFO )

	   CHARACTER	  UPLO

	   INTEGER	  INFO, N

	   COMPLEX*16	  AP( * )

PURPOSE
       ZPPTRI computes the inverse of a complex Hermitian positive definite matrix A using the Cholesky factorization A = U**H*U  or  A  =  L*L**H
       computed by ZPPTRF.

ARGUMENTS
       UPLO    (input) CHARACTER*1
	       = 'U':  Upper triangular factor is stored in AP;
	       = 'L':  Lower triangular factor is stored in AP.

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.

       AP      (input/output) COMPLEX*16 array, dimension (N*(N+1)/2)
	       On  entry,  the	triangular  factor  U or L from the Cholesky factorization A = U**H*U or A = L*L**H, packed columnwise as a linear
	       array.  The j-th column of U or L is stored in the array AP as follows: if UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for  1<=i<=j;	if
	       UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.

	       On exit, the upper or lower triangle of the (Hermitian) inverse of A, overwriting the input factor U or L.

       INFO    (output) INTEGER
	       = 0:  successful exit
	       < 0:  if INFO = -i, the i-th argument had an illegal value
	       > 0:  if INFO = i, the (i,i) element of the factor U or L is zero, and the inverse could not be computed.

LAPACK version 3.0						   15 June 2000 							 ZPPTRI(l)