CompareLocalEstimators.h

#pragma once

#if defined(CompareLocalEstimators_RECURSES)
#error Recursive header files inclusion detected in CompareLocalEstimators.h
#else // defined(CompareLocalEstimators_RECURSES)

#define CompareLocalEstimators_RECURSES

#if !defined CompareLocalEstimators_h

#define CompareLocalEstimators_h

// Inclusions
#include <cmath>
#include <iostream>
#include "DGtal/base/Common.h"
#include "DGtal/base/Statistic.h"

namespace DGtal
{
  // template class CompareLocalEstimators
  template <typename TFirstEsimator, typename TSecondEstimator>
  struct CompareLocalEstimators
  {

    // ----------------------- Types ------------------------------
  public:

    typedef TFirstEsimator FirstEstimator;
    typedef TSecondEstimator SecondEstimator;

    typedef typename FirstEstimator::ConstIterator ConstIterator;
    typedef typename FirstEstimator::Quantity Quantity;

    typedef Statistic<Quantity> OutputStatistic;
    typedef Statistic<double> OutputVectorStatistic;
    
    
    // ----------------------- Interface --------------------------------------
  public:

    static 
    Quantity compare(FirstEstimator & aFirstEstimator,
         SecondEstimator & aSecondEstimator,
         const ConstIterator &it)
    {
      ASSERT( aFirstEstimator.isValid());
      ASSERT( aSecondEstimator.isValid());
      
      return aFirstEstimator.eval(it) - aSecondEstimator.eval(it);
    }
    
    
    static
    OutputStatistic
    compare(FirstEstimator & aFirstEstimator,
      SecondEstimator & aSecondEstimator,
      const ConstIterator & itb, 
      const ConstIterator & ite,
      const bool storeSamples = false)
    {
      OutputStatistic stats(storeSamples);
      
      for(ConstIterator it = itb; it!= ite; ++it)
  stats.addValue( compare(aFirstEstimator,aSecondEstimator,it));
      
      stats.terminate();
      return stats;
    }
    
    
    static 
    double 
    compareVectors(FirstEstimator & aFirstEstimator,
       SecondEstimator & aSecondEstimator,
       const ConstIterator &it)
    {
      ASSERT( aFirstEstimator.isValid());
      ASSERT( aSecondEstimator.isValid());
      Quantity v1 = aFirstEstimator.eval(it), v2 = aSecondEstimator.eval(it);
      
      ASSERT( v1.norm() != 0.0 );
      ASSERT( v2.norm() != 0.0 );
      double ndot = (double) v1.dot(v2)
  / ( (double) ( v1.norm() * v2.norm() ) );
      return ( ndot > 1.0 ) ? 0.0
  : ( ndot < -1.0 ) ? M_PI : acos( ndot );
      
    }
    
    
    static
    OutputVectorStatistic
    compareVectors(FirstEstimator & aFirstEstimator,
       SecondEstimator & aSecondEstimator,
       const ConstIterator & itb, 
       const ConstIterator & ite,
       const bool storeSamples = false)
    {
      OutputVectorStatistic stats(storeSamples);
      
      for(ConstIterator it = itb; it!= ite; ++it)
  stats.addValue( compareVectors(aFirstEstimator,aSecondEstimator,it));
      
      stats.terminate();
      return stats;
    }
    
    // ------------------------- Hidden services ------------------------------
  private:
    
    CompareLocalEstimators ( const CompareLocalEstimators & other );

    CompareLocalEstimators & operator= ( const CompareLocalEstimators & other );


  }; // end of class CompareLocalEstimators

} // namespace DGtal



#endif // !defined CompareLocalEstimators_h

#undef CompareLocalEstimators_RECURSES
#endif // else defined(CompareLocalEstimators_RECURSES)