chetri2x.f - Man Page

SRC/chetri2x.f

Synopsis

Functions/Subroutines

subroutine chetri2x (uplo, n, a, lda, ipiv, work, nb, info)
CHETRI2X

Function/Subroutine Documentation

subroutine chetri2x (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, integer, dimension( * ) ipiv, complex, dimension( n+nb+1,* ) work, integer nb, integer info)

CHETRI2X  

Purpose:

 CHETRI2X computes the inverse of a complex Hermitian indefinite matrix
 A using the factorization A = U*D*U**H or A = L*D*L**H computed by
 CHETRF.
Parameters

UPLO

          UPLO is CHARACTER*1
          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**H;
          = 'L':  Lower triangular, form is A = L*D*L**H.

N

          N is INTEGER
          The order of the matrix A.  N >= 0.

A

          A is COMPLEX array, dimension (LDA,N)
          On entry, the NNB diagonal matrix D and the multipliers
          used to obtain the factor U or L as computed by CHETRF.

          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.

LDA

          LDA is INTEGER
          The leading dimension of the array A.  LDA >= max(1,N).

IPIV

          IPIV is INTEGER array, dimension (N)
          Details of the interchanges and the NNB structure of D
          as determined by CHETRF.

WORK

          WORK is COMPLEX array, dimension (N+NB+1,NB+3)

NB

          NB is INTEGER
          Block size

INFO

          INFO is INTEGER
          = 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.
Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 119 of file chetri2x.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page chetri2x(3) is an alias of chetri2x.f(3).

Tue Nov 28 2023 12:08:41 Version 3.12.0 LAPACK