Example #1
0
void GBDT::LogLossProcess(DataVector *d, size_t samples, int i) {
#ifdef USE_OPENMP
#pragma omp parallel for
#endif
  for (size_t j = 0; j < samples; ++j) {
    ValueType p = Predict(*(*d)[j], i);
    (*d)[j]->target =
        static_cast<ValueType>(LogitLossGradient((*d)[j]->label, p));
  }

  if (g_conf.debug) {
    Auc auc;
    DataVector::iterator iter = d->begin();
    for ( ; iter != d->end(); ++iter) {
      ValueType p = Logit(Predict(**iter, i));
      auc.Add(p, (*iter)->label);
    }
    std::cout << "auc: " << auc.CalculateAuc() << std::endl;
  }
}
Example #2
0
int main(int argc, char *argv[]) {
  std::srand ( unsigned ( std::time(0) ) );

#ifdef USE_OPENMP
  const int threads_wanted = 4;
  omp_set_num_threads(threads_wanted);
#endif

  g_conf.number_of_feature = 79;
  g_conf.max_depth = 6;
  g_conf.iterations = 10;
  g_conf.shrinkage = 0.1F;

  if (argc < 3) return -1;

  std::string train_file(argv[1]);
  std::string test_file(argv[2]);

  if (argc > 3) {
    g_conf.max_depth = boost::lexical_cast<int>(argv[3]);
  }

  if (argc > 4) {
    g_conf.iterations = boost::lexical_cast<int>(argv[4]);
  }

  if (argc > 5) {
    g_conf.shrinkage = boost::lexical_cast<float>(argv[5]);
  }

  if (argc > 6) {
    g_conf.feature_sample_ratio = boost::lexical_cast<float>(argv[6]);
  }

  if (argc > 7) {
    g_conf.data_sample_ratio = boost::lexical_cast<float>(argv[7]);
  }

  int debug = 0;
  if (argc > 8) {
    debug = boost::lexical_cast<int>(argv[8]);
  }

  g_conf.loss = LOG_LIKELIHOOD;
  g_conf.debug = debug > 0? true : false;

  DataVector d;
  bool r = LoadDataFromFile(train_file, &d);
  assert(r);

  g_conf.min_leaf_size = d.size() / 40;
  std::cout << "configure: " << std::endl
            << g_conf.ToString() << std::endl;

  if (argc > 9) {
    g_conf.LoadFeatureCost(argv[9]);
  }

  GBDT gbdt;
  Elapsed elapsed;
  gbdt.Fit(&d);
  std::cout << "fit time: " << elapsed.Tell() << std::endl;

  std::string model_file = train_file + ".model";
  std::ofstream model_output(model_file.c_str());
  model_output << gbdt.Save();

  CleanDataVector(&d);
  FreeVector(&d);

  DataVector d2;
  r = LoadDataFromFile(test_file, &d2);
  assert(r);

  elapsed.Reset();
  DataVector::iterator iter = d2.begin();
  PredictVector predict;
  for ( ; iter != d2.end(); ++iter) {
    ValueType p = Logit(gbdt.Predict(**iter));
    predict.push_back(p);

  }
  std::cout << "predict time: " << elapsed.Tell() << std::endl;

  std::string predict_file = test_file + ".predict";
  std::ofstream predict_output(predict_file.c_str());

  Auc auc;
  for (size_t i = 0; i < d2.size(); ++i) {
    predict_output << predict[i] << " " << d2[i]->ToString() << std::endl;
    auc.Add(predict[i], d2[i]->label);
  }
  std::cout << "auc: " << auc.CalculateAuc() << std::endl;
  auc.PrintConfusionTable();

  CleanDataVector(&d2);

  return 0;
}
Example #3
0
void GBDT::Fit(DataVector *d) {
  delete[] trees;
  trees = new RegressionTree[g_conf.iterations];

  size_t samples = d->size();
  if (g_conf.data_sample_ratio < 1) {
    samples = static_cast<size_t>(d->size() * g_conf.data_sample_ratio);
  }

  Init(*d, d->size());

  for (size_t i = 0; i < g_conf.iterations; ++i) {
    std::cout  << "iteration: " << i << std::endl;

    if (samples < d->size()) {
#ifndef USE_OPENMP
      std::random_shuffle(d->begin(), d->end());
#else
      __gnu_parallel::random_shuffle(d->begin(), d->end());
#endif
    }

    if (g_conf.loss == SQUARED_ERROR) {
      for (size_t j = 0; j < samples; ++j) {
        ValueType p = Predict(*(*d)[j], i);
        (*d)[j]->target = (*d)[j]->label - p;
      }

      if (g_conf.debug) {
        double s = 0;
        double c = 0;
        DataVector::iterator iter = d->begin();
        for ( ; iter != d->end(); ++iter) {
          ValueType p = Predict(**iter, i);
          s += Squared((*iter)->label - p) * (*iter)->weight;
          c += (*iter)->weight;
        }
        std::cout << "rmse: " << std::sqrt(s / c) << std::endl;
      }
    } else if (g_conf.loss == LOG_LIKELIHOOD) {
      for (size_t j = 0; j < samples; ++j) {
        ValueType p = Predict(*(*d)[j], i);
        (*d)[j]->target =
            static_cast<ValueType>(LogitLossGradient((*d)[j]->label, p));
      }

      if (g_conf.debug) {
        Auc auc;
        DataVector::iterator iter = d->begin();
        for ( ; iter != d->end(); ++iter) {
          ValueType p = Logit(Predict(**iter, i));
          auc.Add(p, (*iter)->label);
        }
        std::cout << "auc: " << auc.CalculateAuc() << std::endl;
      }
    }

    trees[i].Fit(d, samples);
  }


  // Calculate gain
  delete[] gain;
  gain = new double[g_conf.number_of_feature];

  for (size_t i = 0; i < g_conf.number_of_feature; ++i) {
    gain[i] = 0.0;
  }

  for (size_t j = 0; j < iterations; ++j) {
    double *g = trees[j].GetGain();
    for (size_t i = 0; i < g_conf.number_of_feature; ++i) {
      gain[i] += g[i];
    }
  }
}