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dsytri2x.f(3)                       LAPACK                       dsytri2x.f(3)

NAME
       dsytri2x.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dsytri2x (UPLO, N, A, LDA, IPIV, WORK, NB, INFO)
           DSYTRI2X

Function/Subroutine Documentation
   subroutine dsytri2x (characterUPLO, integerN, double precision, dimension(
       lda, * )A, integerLDA, integer, dimension( * )IPIV, double precision,
       dimension( n+nb+1,* )WORK, integerNB, integerINFO)
       DSYTRI2X

       Purpose:

            DSYTRI2X computes the inverse of a real symmetric indefinite matrix
            A using the factorization A = U*D*U**T or A = L*D*L**T computed by
            DSYTRF.

       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**T;
                     = 'L':  Lower triangular, form is A = L*D*L**T.

           N

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

           A

                     A is DOUBLE PRECISION 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 DSYTRF.

                     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 DSYTRF.

           WORK

                     WORK is DOUBLE PRECISION array, dimension (N+NNB+1,NNB+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.

       Date:
           November 2011

       Definition at line 121 of file dsytri2x.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                  dsytri2x.f(3)