Function GenerateCatDMatrix

tests/cpp/tree/test_column_split.h:15–30

namespace xgboost::tree {
inline std::shared_ptr<DMatrix> GenerateCatDMatrix(std::size_t rows, std::size_t cols,
                                                   float sparsity, bool categorical) {
  if (categorical) {
    std::vector<FeatureType> ft(cols);
    for (size_t i = 0; i < ft.size(); ++i) {
      ft[i] = (i % 3 == 0) ? FeatureType::kNumerical : FeatureType::kCategorical;
    }
    return RandomDataGenerator(rows, cols, sparsity)
        .Seed(3)
        .Type(ft)
        .MaxCategory(17)
        .GenerateDMatrix();
  } else {
    return RandomDataGenerator{rows, cols, sparsity}.Seed(3).GenerateDMatrix();
  }
}

void TestColumnSplit(bst_target_t n_targets, bool categorical, std::string name, float sparsity);
}  // namespace xgboost::tree