Function GenerateRandomCategoricalSingleColumn

tests/cpp/helpers.cc:617–628

}

[[nodiscard]] std::vector<float> GenerateRandomCategoricalSingleColumn(std::size_t n,
                                                                       std::size_t n_categories) {
  std::vector<float> x(n);
  std::mt19937 rng(0);
  std::uniform_int_distribution<size_t> dist(0, n_categories - 1);
  std::generate(x.begin(), x.end(), [&]() { return static_cast<float>(dist(rng)); });
  // Make sure each category is present
  for (size_t i = 0; i < n_categories; i++) {
    x[i] = static_cast<decltype(x)::value_type>(i);
  }
  return x;
}

std::shared_ptr<DMatrix> GetDMatrixFromData(const std::vector<float>& x, std::size_t num_rows,
                                            bst_feature_t num_columns) {