/* $Id: $ */

/* Copyright (C) 1997 Sverre Hvammen Johansen,
 * Department of Informatics, University of Oslo.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "cim.h"
#include "trigno.h"

/******************************************************************************
                                             REAL PROCEDURE COTAN(r)         */

double 
__rcotan (r)
     double r;
{
  double s;
  s = sin (r);
  if (s == 0.0)
    __rerror ("Cotan: Illegal division by zero");
  return (cos (r) / s);
}