Provided by: liblapack-doc_3.3.1-1_all NAME

LAPACK-3  -  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 CPPTRF

SYNOPSIS

SUBROUTINE CPPTRI( UPLO, N, AP, INFO )

CHARACTER      UPLO

INTEGER        INFO, N

COMPLEX        AP( * )

PURPOSE

CPPTRI 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 CPPTRF.

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 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 routine (version 3.3.1)             April 2011                            CPPTRI(3lapack)