source: trunk/lib/classifier/CrossSplitting.h @ 460

// $Id: CrossSplitting.h 460 2005-12-16 12:40:06Z peter $

#ifndef _theplu_classifier_cross_splitting_ 
#define _theplu_classifier_cross_splitting_ 

#include <vector>

namespace theplu {
namespace gslapi {
  class vector;
}
namespace classifier {  

  ///
  /// Class splitting a set into training set and validation set in a
  /// crossvalidation manner.
  ///   
  class CrossSplitting
  {
  
  public:
    ///
    /// Constructor taking \a target and \a k for k-fold cross validation
    ///
    CrossSplitting(const theplu::gslapi::vector& target, const size_t k = 3);

    ///
    /// Function generating a training set. This is done in a balanced
    /// way, meaning the proportions between the classes the
    /// trainingset is close to the proportions in the whole
    /// dataset. In the first \a k rounds each sample is returned k-1
    /// times, for next round the samples are shuffled and...
    ///
    std::vector<size_t> next();

  private:
    int count_;
    std::vector<size_t> index_negative_;
    std::vector<size_t> index_positive_;
    int k_;

         
  };

}} // of namespace classifier and namespace theplu

#endif