Class LightSplitInfo

src/treelearner/split_info.hpp:195–287

};

struct LightSplitInfo {
 public:
  /*! \brief Feature index */
  int feature = -1;
  /*! \brief Split gain */
  double gain = kMinScore;
  /*! \brief Left number of data after split */
  data_size_t left_count = 0;
  /*! \brief Right number of data after split */
  data_size_t right_count = 0;

  inline void Reset() {
    // initialize with -1 and -inf gain
    feature = -1;
    gain = kMinScore;
  }

  void CopyFrom(const SplitInfo& other) {
    feature = other.feature;
    gain = other.gain;
    left_count = other.left_count;
    right_count = other.right_count;
  }

  void CopyFrom(const char* buffer) {
    std::memcpy(&feature, buffer, sizeof(feature));
    buffer += sizeof(feature);
    std::memcpy(&left_count, buffer, sizeof(left_count));
    buffer += sizeof(left_count);
    std::memcpy(&right_count, buffer, sizeof(right_count));
    buffer += sizeof(right_count);
    std::memcpy(&gain, buffer, sizeof(gain));
    buffer += sizeof(gain);
  }

  inline bool operator > (const LightSplitInfo& si) const {
    double local_gain = this->gain;
    double other_gain = si.gain;
    // replace nan with -inf
    if (local_gain == NAN) {
      local_gain = kMinScore;
    }
    // replace nan with -inf
    if (other_gain == NAN) {
      other_gain = kMinScore;
    }
    int local_feature = this->feature;
    int other_feature = si.feature;
    // replace -1 with max int
    if (local_feature == -1) {
      local_feature = INT32_MAX;
    }
    // replace -1 with max int
    if (other_feature == -1) {
      other_feature = INT32_MAX;
    }
    if (local_gain != other_gain) {
      return local_gain > other_gain;