#ifndef __LINEAR_LOGARITHMIC_INTERPOLATION_TEMPLATE_CLASS__
#define __LINEAR_LOGARITHMIC_INTERPOLATION_TEMPLATE_CLASS__ 
/**
      @file LinLogInterp.hpp
      @author Brian Magill
      @datecreated 8/17/2006

	  $Date:$
      $Revision:$

      @copyright
      (©) Copyright 2006 by GATS Inc.
      11864 Canon Blvd., Suite 101, Newport News, VA 23606

      All Rights Reserved. No part of this software or publication may be
      reproduced, stored in a retrieval system, or transmitted, in any form
      or by any means, electronic, mechanical, photocopying, recording, or
      otherwise without the prior written permission of GATS Inc.
 
      @brief Function Template for linear logarithmic interpolation 
      
      Here the independent variable is approximately linear and the 
      logarithm of the dependent variable is approximately linear.
      
*/
//----------------------------------------------------------------------
//

#include "VectorLinInterp.hpp"
#include <cmath>
#include <cassert>
#include <vector>
#include <algorithm>

template <typename T> 
T LinLogInterp(T const x, T const xa, T const xb, T const ya, T const yb) 
{

VectorLinInterp<T> A;

assert( ya > 0. && yb > 0.);

T za = log(ya);
T zb = log(yb);
T z_out = A.linear_interpolate(x, xa, xb, za, zb);

T result = exp(z_out);

return result;

};

template <typename T> 
class Log
{
public:
    Log() {} ;
    
    ~Log() {}; 
    
T operator () (T x)
        {
        return log(x);
        }   
    
};


template <typename T> 
T LinLogInterp(std::vector<T> const &yin, std::vector<T> const  &xin, T const &xout) 
{

assert( yin.size() > 0. && xin.size() > 0.);

VectorLinInterp<T> A;
std::vector<T> z_in(yin.size() );

transform(yin.begin(),yin.end(), z_in.begin(), Log<T>() );

T z_out =  A.Interpol(z_in, xin, xout);

T result = exp(z_out);

return result;

};

#endif