/**
   \file bpl.hpp
   \brief broken power law
   \author Junhua Gu
 */


#ifndef BROKEN_POWER_LAW_MODEL_H_
#define BROKEN_POWER_LAW_MODEL_H_
#define OPT_HEADER
#include <core/fitter.hpp>
#include <cmath>
#include <misc/optvec.hpp>

namespace opt_utilities
{
  template <typename T>
  class bpl1d
    :public model<optvec<T>,optvec<T>,optvec<T>,std::string>
  {
  private:
    bpl1d* do_clone()const
    {
      return new bpl1d<T>(*this);
    }

    const char* do_get_type_name()const
    {
      return "broken power law";
    }
  public:
    bpl1d()
    {
      this->push_param_info(param_info<optvec<T> >("bpx",1));
      this->push_param_info(param_info<optvec<T> >("bpy",1));
      this->push_param_info(param_info<optvec<T> >("gamma1",1));
      this->push_param_info(param_info<optvec<T> >("gamma2",1));
    }

    optvec<T> do_eval(const optvec<T>& x,const optvec<T>& param)
    {
      T x_b=get_element(param,0);
      T f_b=get_element(param,1);
      T gamma1=get_element(param,2);
      T gamma2=get_element(param,3);
      
      optvec<T> result(x.size());
      for(int i=0;i<result.size();++i)
	{
	  if(x[i]<x_b)
	    {
	      result[i]=f_b*pow(x[i],gamma1)/pow(x_b,gamma1);
	    }
	  else
	    {
	      result[i]=f_b*pow(x[i],gamma2)/pow(x_b,gamma2);
	    }
	}
      return result;
    }
    

  private:
    std::string do_get_information()const
    {
#include <model_doc/bpl.info>
    }
  };
}



#endif
//EOF