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NAME
     checon - estimate the reciprocal of the condition number  of
     a  complex  Hermitian  matrix  A using the factorization A =
     U*D*U**H or A = L*D*L**H computed by CHETRF

SYNOPSIS
     SUBROUTINE CHECON( UPLO, N,  A,  LDA,  IPIV,  ANORM,  RCOND,
               WORK, INFO )

     CHARACTER UPLO

     INTEGER INFO, LDA, N

     REAL ANORM, RCOND

     INTEGER IPIV( * )

     COMPLEX A( LDA, * ), WORK( * )



     #include <sunperf.h>

     void checon(char uplo, int n,  complex  *ca,  int  lda,  int
               *ipivot, float anorm, float *srcond, int *info);

PURPOSE
     CHECON estimates the reciprocal of the condition number of a
     complex  Hermitian  matrix  A  using  the  factorization A =
     U*D*U**H or A = L*D*L**H computed by CHETRF.

     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**H;
               = 'L':  Lower triangular, form is A = L*D*L**H.

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

     A         (input) COMPLEX array, dimension (LDA,N)
               The block diagonal matrix D  and  the  multipliers
               used  to  obtain  the factor U or L as computed by
               CHETRF.

     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  block  struc-
               ture of D as determined by CHETRF.

     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),
               where AINVNM is  an  estimate  of  the  1-norm  of
               inv(A) computed in this routine.

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

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

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