Method getField

src/mesh/data/gridfromfile.cxx:135–327

template <typename T>
bool GridFile::getField(Mesh* m, T& var, const std::string& name, BoutReal def,
                        CELL_LOC location) {
  static_assert(
      bout::utils::is_Field_v<T>,
      "templated GridFile::getField only works for Field2D, Field3D or FieldPerp");

  Timer timer("io");
  AUTO_TRACE();

  if (not data.isSet(name)) {
    // Variable not found
    output_warn.write("\tWARNING: Could not read '{:s}' from grid. Setting to {:e}\n",
                      name, def);
    var = def;
    var.setLocation(location);
    return false;
  }

  Options& option = data[name];

  // Global (x, y, z) dimensions of field
  const std::vector<int> size = option.getShape();

  switch (size.size()) {
  case 1: {
    // 0 or 1 dimension
    if (size[0] != 1) {
      throw BoutException(
          "Expecting a 2D variable, but '{:s}' is 1D with {:d} elements\n", name,
          size[0]);
    }
    var = option.as<BoutReal>();
    var.setLocation(location);
    return true;
  }
  case 2: {
    // Check size
    break;
  }
  case 3: {
    // Check size if getting Field3D
    if constexpr (bout::utils::is_Field2D_v<T> or bout::utils::is_FieldPerp_v<T>) {
      output_warn.write(
          "WARNING: Variable '{:s}' should be 2D, but has {:d} dimensions. Ignored\n",
          name, size.size());
      var = def;
      var.setLocation(location);
      return false;
    }
    break;
  }
  default: {
    output_warn.write(
        "WARNING: Variable '{:s}' should be 2D or 3D, but has {:d} dimensions. Ignored\n",
        name, size.size());
    var = def;
    var.setLocation(location);
    return false;