def validate_row_dependent_constants(umf, rdc_valid):
    """
    Check that the row dependent constants associated with a :class:`UMFile`
    object are the expected size.

    .. Note::
        This does not confirm that the constants are present, since
        these constants are optional; the caller must check this separately.

    Args:
        * umf:
            A :class:`UMFile` subclass instance.
        * rdc_valid:
            Tuple containing the size of the two expected dimensions
            of the row dependent constants to be checked against.

    """
    out_msg = []
    rdc_shape = umf.row_dependent_constants.shape
    if rdc_shape != rdc_valid:
        msg = ("Incorrectly shaped row dependent constants based on "
               "file type and number of rows in integer_constants "
               "(found {0}, should be {1})")
        out_msg = [msg.format(rdc_shape, rdc_valid)]
    return out_msg