Value.h

//-*-C++-*-
/***************************************************************************
 *
 *   Copyright (C) 2011 by Willem van Straten
 *   Licensed under the Academic Free License version 2.1
 *
 ***************************************************************************/
 
// psrchive/More/MEAL/MEAL/Complex2Value.h
 
#ifndef __MEAL_Value_H
#define __MEAL_Value_H
 
#include "MEAL/NoParameters.h"
#include "MEAL/NotCached.h"
 
namespace MEAL {

  template<typename T>
  class Value : public T {
 
  public:
 
    typedef typename T::Result Result;

    Value () { init(); }

    Value (const Result& _value) { init(); value = _value; }

    void set_value (const Result& _value)
    {
      if (value == _value)
        return;
 
      value = _value;
      this->set_evaluation_changed();
    }

    const Result& get_value () const { return value; }

    std::string get_name () const
    { return "Value<" + std::string(T::Name)+ ">"; }
 
  protected:

    void calculate (Result& result, std::vector<Result>* grad=0)
    {
      result = value;
      if (grad) grad->resize(0);
    }
 
    void init ()
    {
      this->parameter_policy = new NoParameters;
      this->evaluation_policy = new NotCached<T> (this);
    }

    Result value;
 
  };
 
}
 
#endif