Function MakeQDMForTest

tests/cpp/c_api/test_c_api.cc:426–456

}

auto MakeQDMForTest(Context const *ctx, bst_idx_t n_samples, bst_feature_t n_features,
                    Json dconfig) {
  bst_bin_t n_bins{16};
  dconfig["max_bin"] = Integer{n_bins};

  std::size_t n_batches{4};
  std::unique_ptr<ArrayIterForTest> iter_0;
  if (ctx->IsCUDA()) {
    iter_0 = std::make_unique<CudaArrayIterForTest>(0.0f, n_samples, n_features, n_batches);
  } else {
    iter_0 = std::make_unique<NumpyArrayIterForTest>(0.0f, n_samples, n_features, n_batches);
  }
  std::string s_dconfig;
  Json::Dump(dconfig, &s_dconfig);
  DMatrixHandle p_fmat;
  CHECK_EQ(XGQuantileDMatrixCreateFromCallback(static_cast<DataIterHandle>(iter_0.get()),
                                               iter_0->Proxy(), nullptr, Reset, Next,
                                               s_dconfig.c_str(), &p_fmat),
           0);

  std::unique_ptr<ArrayIterForTest> iter_1;
  if (ctx->IsCUDA()) {
    iter_1 = std::make_unique<CudaArrayIterForTest>(0.0f, n_samples, n_features, n_batches);
  } else {
    iter_1 = std::make_unique<NumpyArrayIterForTest>(0.0f, n_samples, n_features, n_batches);
  }
  auto Xy =
      std::make_shared<data::IterativeDMatrix>(iter_1.get(), iter_1->Proxy(), nullptr, Reset, Next,
                                               std::numeric_limits<float>::quiet_NaN(), 0, n_bins);
  return std::pair{p_fmat, Xy};
}

auto MakeExtMemForTest(bst_idx_t n_samples, bst_feature_t n_features, Json dconfig) {
  std::size_t n_batches{4};