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

NAME

       LAPACK-3  -  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

SYNOPSIS

       SUBROUTINE DSYTRI2X( UPLO, N, A, LDA, IPIV, WORK, NB, INFO )

           CHARACTER        UPLO

           INTEGER          INFO, LDA, N, NB

           INTEGER          IPIV( * )

           DOUBLE           PRECISION A( LDA, * ), WORK( N+NB+1,* )

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.

ARGUMENTS

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

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

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

        WORK    (workspace) DOUBLE PRECISION array, dimension (N+NNB+1,NNB+3)

        NB      (input) INTEGER
                Block size

        INFO    (output) 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.

 LAPACK routine (version 3.3.1)             April 2011                          DSYTRI2X(3lapack)