SRC/zsptri.f(3)

NAME
SRC/zsptri.f

SYNOPSIS

  Functions/Subroutines
subroutine zsptri (uplo, n, ap, ipiv, work, info)
ZSPTRI

Function/Subroutine Documentation

  subroutine zsptri (character uplo, integer n, complex*16, dimension( * ) ap, integer, dimension( * ) ipiv, complex*16, dimension( * ) work, integer info)

ZSPTRI

Purpose:

    !>
    !> ZSPTRI computes the inverse of a complex symmetric indefinite matrix
    !> A in packed storage using the factorization A = U*D*U**T or
    !> A = L*D*L**T computed by ZSPTRF.
    !>

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.
    !>

    AP

    !>          AP is COMPLEX*16 array, dimension (N*(N+1)/2)
    !>          On entry, the block diagonal matrix D and the multipliers
    !>          used to obtain the factor U or L as computed by ZSPTRF,
    !>          stored as a packed triangular matrix.
    !>
    !>          On exit, if INFO = 0, the (symmetric) inverse of the original
    !>          matrix, stored as a packed triangular matrix. The j-th column
    !>          of inv(A) is stored in the array AP as follows:
    !>          if UPLO = 'U', AP(i + (j-1)*j/2) = inv(A)(i,j) for 1<=i<=j;
    !>          if UPLO = 'L',
    !>             AP(i + (j-1)*(2n-j)/2) = inv(A)(i,j) for j<=i<=n.
    !>

    IPIV

    !>          IPIV is INTEGER array, dimension (N)
    !>          Details of the interchanges and the block structure of D
    !>          as determined by ZSPTRF.
    !>

    WORK

    !>          WORK is COMPLEX*16 array, dimension (N)
    !>

    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 108 of file zsptri.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.