text: /**
   * \copyright
   * Copyright (c) 2020, OpenGeoSys Community (http://www.opengeosys.org)
   *            Distributed under a Modified BSD License.
   *              See accompanying file LICENSE.txt or
   *              http://www.opengeosys.org/project/license
   *
   */
  
  class NR
  {
  private:
  public:
      NR(void);
      ~NR(void);
  
      static double dfridr(double func(double), const double /*x*/);
      static double dfridrX(double func(double, double), const double /*x*/,
                            const double /*y*/);
      static double dfridrY(double func(double, double), const double /*x*/,
                            const double /*y*/);
  };
  