Function GetArrayInterface

tests/cpp/helpers.h:212–231

template <typename T>
Json GetArrayInterface(HostDeviceVector<T> const* storage, size_t rows, size_t cols) {
  Json array_interface{Object()};
  array_interface["data"] = std::vector<Json>(2);
  if (storage->DeviceCanRead()) {
    array_interface["data"][0] = Integer{reinterpret_cast<int64_t>(storage->ConstDevicePointer())};
    array_interface["stream"] = nullptr;
  } else {
    array_interface["data"][0] = Integer{reinterpret_cast<int64_t>(storage->ConstHostPointer())};
  }
  array_interface["data"][1] = Boolean(false);

  array_interface["shape"] = std::vector<Json>(2);
  array_interface["shape"][0] = rows;
  array_interface["shape"][1] = cols;

  char t = linalg::detail::ArrayInterfaceHandler::TypeChar<T>();
  array_interface["typestr"] = String(std::string{"<"} + t + std::to_string(sizeof(T)));
  array_interface["version"] = 3;
  return array_interface;
}

// Generate in-memory random data without using DMatrix.
class RandomDataGenerator {