1 /** 2 * Copyright 2020 Huawei Technologies Co., Ltd 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #ifndef MINDSPORE_LITE_INCLUDE_TRAIN_LR_SCHEDULER_H_ 17 #define MINDSPORE_LITE_INCLUDE_TRAIN_LR_SCHEDULER_H_ 18 #include <vector> 19 #include <string> 20 #include <utility> 21 #include <functional> 22 #include <unordered_map> 23 #include "include/train/train_loop_callback.h" 24 25 namespace mindspore { 26 namespace lite { 27 28 constexpr int DONT_UPDATE_LR = 0; 29 constexpr int UPDATE_LR = 1; 30 31 using LR_Lambda = std::function<int(float *lr, int epoch, void *cb_data)>; 32 33 /// \brief Multiply the LR by a factor of gamma every epoch 34 int MultiplicativeLRLambda(float *lr, int epoch, void *multiplication); 35 36 /// \brief Multiply the LR by a factor of gamma every step_size 37 int StepLRLambda(float *lr, int epoch, void *step_size); 38 struct StepLRLambda { StepLRLambdaStepLRLambda39 StepLRLambda(int step, float g) : step_size(step), gamma(g) {} 40 41 int step_size; // period of LR decay 42 float gamma; // LR decay factor 43 }; 44 45 class LRScheduler : public session::TrainLoopCallBack { 46 public: 47 explicit LRScheduler(LR_Lambda lambda_func, void *lr_cb_data = nullptr, int step_ = 1); 48 virtual ~LRScheduler() = default; 49 int EpochEnd(const session::TrainLoopCallBackData &cb_data) override; 50 51 private: 52 LR_Lambda lambda_func_; 53 void *lr_data_ = nullptr; 54 int step_ = 1; 55 }; 56 57 } // namespace lite 58 } // namespace mindspore 59 #endif // MINDSPORE_LITE_INCLUDE_TRAIN_LR_SCHEDULER_H_ 60