SRC/csptri.f(3)

NAME
SRC/csptri.f

SYNOPSIS

  Functions/Subroutines
subroutine csptri (uplo, n, ap, ipiv, work, info)
CSPTRI

Function/Subroutine Documentation

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

CSPTRI

Purpose:

     CSPTRI 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 CSPTRF.

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 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 CSPTRF,
              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 CSPTRF.

    WORK

              WORK is COMPLEX 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 csptri.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.