source: trunk/c++_tools/classifier/Kernel_MEV.h @ 651

#ifndef _theplu_classifier_kernel_mev_
#define _theplu_classifier_kernel_mev_

// $Id$

#include <c++_tools/classifier/DataLookup1D.h>
#include <c++_tools/classifier/Kernel.h>
#include <c++_tools/classifier/KernelFunction.h>

namespace theplu {
namespace classifier {
  class MatrixLookup;
  class MatrixLookupWeighted;

  ///
  /// @brief Memory Efficient Kernel 
  ///
  ///   Class taking care of the
  ///   \f$ NxN \f$ kernel matrix, where \f$ N \f$ is number of
  ///   samples. Type of Kernel is defined by a KernelFunction. This
  ///   Memory Efficient Version (MEV) does not store the kernel
  ///   matrix in memory, but calculates an element when it is
  ///   needed. When memory allows do always use Kernel_SEV
  ///   instead. 
  ///
  class Kernel_MEV : public Kernel 
  {
    
  public:
    
    ///
    /// Constructor taking the data matrix and KernelFunction as
    /// input.Each column in the data matrix corresponds to one
    /// sample. @note Can not handle NaNs. 
    ///
    Kernel_MEV(const MatrixLookup& data, const KernelFunction& kf);


    ///
    /// Constructor taking the data matrix and KernelFunction as
    /// input.Each column in the data matrix corresponds to one
    /// sample. @note Can not handle NaNs. 
    ///
    Kernel_MEV(const MatrixLookupWeighted& data, const KernelFunction& kf);


    ///
    /// Constructing a new Kernel based on selected features @a
    /// index. All other seeting are the same.
    ///
    Kernel_MEV(const Kernel_MEV& kernel, const std::vector<size_t>& index);


    ///
    /// Destructor
    ///
    inline virtual ~Kernel_MEV(void) {};

    ///
    /// @return Element at position (\a row, \a column) of the Kernel
    /// matrix
    ///
    double operator()(const size_t row, const size_t column) const;
    
    /// 
    /// @see Kernel_MEV(const Kernel_MEV&, const std::vector<size_t>&);

    ///
    /// @note returns dynamically allocated pointer that must be
    /// deleted by the caller to avoid memory leaks.
    ///
    const Kernel_MEV* selected(const std::vector<size_t>& index) const;

  private:
    ///
    /// Copy constructor (not implemented)
    ///
    Kernel_MEV(const Kernel_MEV&);
    const Kernel_MEV& operator=(const Kernel_MEV&);

  }; // class Kernel_MEV

}} // of namespace classifier and namespace theplu

#endif