'When the tree needs to be completely recalculated.'

def invalidate_tree(self):

    if (self.model is not None):
        self.ptree.set_tree(self.tree_adapter, weight_adjustment=self.SIZE_CALCULATION[self.size_calc_idx][1], target_class_index=self.target_class_index)
        self.ptree.set_depth_limit(self.depth_limit)
        self._update_main_area()
