source: trunk/lib/classifier/ConsensusInputRanker.cc @ 522

// $Id: ConsensusInputRanker.cc 522 2006-02-23 08:46:13Z peter $


#include <c++_tools/classifier/ConsensusInputRanker.h>

#include <c++_tools/classifier/CrossSplitter.h>
#include <c++_tools/classifier/MatrixLookup.h>
#include <c++_tools/classifier/InputRanker.h>
#include <c++_tools/classifier/Target.h>
#include <c++_tools/statistics/utility.h>
#include <c++_tools/utility/stl_utility.h>
#include <c++_tools/gslapi/matrix.h>

#include <cassert>
#include <iostream>
#include <utility>
#include <vector>


namespace theplu {
namespace classifier {  

  ConsensusInputRanker::ConsensusInputRanker
  (CrossSplitter& sampler, statistics::Score& score_object)
  {
    assert(sampler.size());
    size_t nof_inputs = sampler.training_data().rows();
    id_.resize(nof_inputs);
    rank_.resize(nof_inputs);
    while (sampler.more()){
      // Peter, should support weights also (in sampler???)
      input_rankers_.push_back(InputRanker(sampler.training_data(), 
                                           sampler.training_target(), 
                                           score_object));
      sampler.next();
    }
    update();
  }

  void ConsensusInputRanker::update(void)
  {

    // Sorting with respect to median rank
    std::vector<std::pair<double,size_t> > medians(id_.size());
    for (size_t i=0; i<id_.size(); i++){ 
      std::vector<size_t> ranks(input_rankers_.size());
      for (size_t j=0; j<input_rankers_.size(); j++) {
        ranks[j]=input_rankers_[j].rank(i);
      }
      medians[i].first = statistics::median(ranks);
      medians[i].second = i;
    }
    
    //sort medians and assign id_ and rank_
    sort(medians.begin(), medians.end());
    for (size_t i=0; i<medians.size(); i++){
      id_[i]=medians[i].second;
      rank_[id_[i]]=i;
    }
  }


}} // of namespace classifier and namespace theplu