def METHOD_NAME(self):
    """
    Clear and initialize the predicate's data.
    Returns:
        This predicate.
    """
    self._data.clear()
    for partition in Partition:
        # Column names don't matter, only order.
        # +1 for truth value.
        self._data[partition] = pandas.DataFrame(columns = list(range(len(self._types) + 1)))
    return self