def get_submap_car(map_car, box, mode="round"):
    """Cut a CAR submap (using pixell).

    Parameters
    ----------
    map : CAR map in ``so_map`` format
      the map to be cut
    box : array_like
      The [[fromy,fromx],[toy,tox]] bounding box to select.
      The resulting map will have a bounding box as close
      as possible to this, but will differ slightly due to
      the finite pixel size.

    mode : str
      How to handle partially selected pixels:
      "round": round bounds using standard rules
      "floor": both upper and lower bounds will be rounded down
      "ceil":  both upper and lower bounds will be rounded up
      "inclusive": lower bounds are rounded down, and upper bounds up
      "exclusive": lower bounds are rounded up, and upper bounds down"""

    submap = map_car.copy()
    submap.data = map_car.data.submap(box, mode=mode)
    submap.geometry = map_car.data.submap(box, mode=mode).geometry[1:]

    return submap