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NAME
     zsycon - estimate the reciprocal of the condition number (in
     the  1-norm)  of a complex symmetric matrix A using the fac-
     torization A = U*D*U**T or A = L*D*L**T computed by ZSYTRF

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

     CHARACTER UPLO

     INTEGER INFO, LDA, N

     DOUBLE PRECISION ANORM, RCOND

     INTEGER IPIV( * )

     COMPLEX*16 A( LDA, * ), WORK( * )



     #include <sunperf.h>

     void zsycon(char uplo, int n, doublecomplex  *za,  int  lda,
               int  *ipivot,  double  anorm,  double *drcond, int
               *info);

PURPOSE
     ZSYCON estimates the reciprocal of the condition number  (in
     the  1-norm)  of a complex symmetric matrix A using the fac-
     torization A = U*D*U**T or A = L*D*L**T computed by ZSYTRF.

     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.

     A         (input) COMPLEX*16 array, dimension (LDA,N)
               The block diagonal matrix D  and  the  multipliers
               used  to  obtain  the factor U or L as computed by
               ZSYTRF.

     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 ZSYTRF.

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

     RCOND     (output) DOUBLE PRECISION
               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*16 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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