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ZSYTRI(1) LAPACK routine (version 3.2) ZSYTRI(1)

NAME

ZSYTRI - computes the inverse of a complex symmetric indefinite matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by ZSYTRF

SYNOPSIS

UPLO, N, A, LDA, IPIV, WORK, INFO )

CHARACTER UPLO INTEGER INFO, LDA, N INTEGER IPIV( * ) COMPLEX*16 A( LDA, * ), WORK( * )

PURPOSE

ZSYTRI computes the inverse of a complex symmetric indefinite matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by ZSYTRF.

ARGUMENTS

Specifies whether the details of the factorization are stored as an upper or lower triangular matrix. = 'U': Upper triangular, form is A = U*D*U**T;
= 'L': Lower triangular, form is A = L*D*L**T.
The order of the matrix A. N >= 0.
On entry, the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ZSYTRF. On exit, if INFO = 0, the (symmetric) inverse of the original matrix. If UPLO = 'U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if UPLO = 'L' the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.
The leading dimension of the array A. LDA >= max(1,N).
Details of the interchanges and the block structure of D as determined by ZSYTRF.
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
> 0: if INFO = i, D(i,i) = 0; the matrix is singular and its inverse could not be computed.
November 2008 LAPACK routine (version 3.2)