# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.## Licensed under the Apache License, Version 2.0 (the "License");# you may not use this file except in compliance with the License.# You may obtain a copy of the License at## http://www.apache.org/licenses/LICENSE-2.0## Unless required by applicable law or agreed to in writing, software# distributed under the License is distributed on an "AS IS" BASIS,# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.# See the License for the specific language governing permissions and# limitations under the License.classIntervalTrigger(object):"""A Predicate to do something every N cycle."""def__init__(self,period:int,unit:str):ifunitnotin("iteration","epoch"):raiseValueError("unit should be 'iteration' or 'epoch'")ifperiod<=0:raiseValueError("period should be a positive integer.")self.period=periodself.unit=unitself.last_index=Nonedef__call__(self,trainer):ifself.last_indexisNone:last_index=getattr(trainer.updater.state,self.unit)self.last_index=last_indexlast_index=self.last_indexindex=getattr(trainer.updater.state,self.unit)fire=index//self.period!=last_index//self.periodself.last_index=indexreturnfire