Method NodeToJSON

src/io/tree.cpp:263–321

}

std::string Tree::NodeToJSON(int index) const {
  std::stringstream str_buf;
  str_buf << std::setprecision(std::numeric_limits<double>::digits10 + 2);
  if (index >= 0) {
    // non-leaf
    str_buf << "{" << '\n';
    str_buf << "\"split_index\":" << index << "," << '\n';
    str_buf << "\"split_feature\":" << split_feature_[index] << "," << '\n';
    str_buf << "\"split_gain\":" << Common::AvoidInf(split_gain_[index]) << "," << '\n';
    if (GetDecisionType(decision_type_[index], kCategoricalMask)) {
      int cat_idx = static_cast<int>(threshold_[index]);
      std::vector<int> cats;
      for (int i = cat_boundaries_[cat_idx]; i < cat_boundaries_[cat_idx + 1]; ++i) {
        for (int j = 0; j < 32; ++j) {
          int cat = (i - cat_boundaries_[cat_idx]) * 32 + j;
          if (Common::FindInBitset(cat_threshold_.data() + cat_boundaries_[cat_idx],
                                   cat_boundaries_[cat_idx + 1] - cat_boundaries_[cat_idx], cat)) {
            cats.push_back(cat);
          }
        }
      }
      str_buf << "\"threshold\":\"" << Common::Join(cats, "||") << "\"," << '\n';
      str_buf << "\"decision_type\":\"==\"," << '\n';
    } else {
      str_buf << "\"threshold\":" << Common::AvoidInf(threshold_[index]) << "," << '\n';
      str_buf << "\"decision_type\":\"<=\"," << '\n';
    }
    if (GetDecisionType(decision_type_[index], kDefaultLeftMask)) {
      str_buf << "\"default_left\":true," << '\n';
    } else {
      str_buf << "\"default_left\":false," << '\n';
    }
    uint8_t missing_type = GetMissingType(decision_type_[index]);
    if (missing_type == 0) {
      str_buf << "\"missing_type\":\"None\"," << '\n';
    } else if (missing_type == 1) {
      str_buf << "\"missing_type\":\"Zero\"," << '\n';
    } else {
      str_buf << "\"missing_type\":\"NaN\"," << '\n';
    }
    str_buf << "\"internal_value\":" << internal_value_[index] << "," << '\n';
    str_buf << "\"internal_weight\":" << internal_weight_[index] << "," << '\n';
    str_buf << "\"internal_count\":" << internal_count_[index] << "," << '\n';
    str_buf << "\"left_child\":" << NodeToJSON(left_child_[index]) << "," << '\n';
    str_buf << "\"right_child\":" << NodeToJSON(right_child_[index]) << '\n';
    str_buf << "}";
  } else {
    // leaf
    index = ~index;
    str_buf << "{" << '\n';
    str_buf << "\"leaf_index\":" << index << "," << '\n';
    str_buf << "\"leaf_value\":" << leaf_value_[index] << "," << '\n';
    str_buf << "\"leaf_weight\":" << leaf_weight_[index] << "," << '\n';
    str_buf << "\"leaf_count\":" << leaf_count_[index] << '\n';
    str_buf << "}";
  }

  return str_buf.str();