SSPCON  -  estimate the reciprocal of the condition number
       (in the 1-norm) of a real symmetric packed matrix A  using
       the factorization A = U*D*U**T or A = L*D*L**T computed by
       SSPTRF


SYNOPSIS

       SUBROUTINE SSPCON( UPLO, N, AP, IPIV, ANORM, RCOND,  WORK,
                          IWORK, INFO )

           CHARACTER      UPLO

           INTEGER        INFO, N

           REAL           ANORM, RCOND

           INTEGER        IPIV( * ), IWORK( * )

           REAL           AP( * ), WORK( * )


PURPOSE

       SSPCON  estimates  the  reciprocal of the condition number
       (in the 1-norm) of a real symmetric packed matrix A  using
       the factorization A = U*D*U**T or A = L*D*L**T computed by
       SSPTRF.  An estimate is obtained for norm(inv(A)), and the
       reciprocal  of the condition number is computed as RCOND =
       1 / (ANORM * norm(inv(A))).


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.

       AP      (input) REAL array, dimension (N*(N+1)/2)
               The block diagonal matrix D  and  the  multipliers
               used  to  obtain  the factor U or L as computed by
               SSPTRF, stored as a packed triangular matrix.

       IPIV    (input) INTEGER array, dimension (N)
               Details of the interchanges and the  block  struc­
               ture of D as determined by SSPTRF.

       ANORM   (input) REAL
               The 1-norm of the original matrix A.

       RCOND   (output) REAL
               The  reciprocal  of  the  condition  number of the
               matrix A, computed as RCOND = 1/(ANORM *  AINVNM),

               inv(A) computed in this routine.

       WORK    (workspace) REAL array, dimension (2*N)

       IWORK    (workspace) INTEGER array, dimension (N)

       INFO    (output) INTEGER
               = 0:  successful exit
               < 0:  if INFO = -i, the i-th argument had an ille­
               gal value


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