text: # Copyright 2021 Huawei Technologies Co., Ltd
  #
  # 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.
  # ============================================================================
  
  """learning rate generator"""
  import numpy as np
  
  
  def get_lr(lr_init, total_epochs, steps_per_epoch):
      """
      generate learning rate array
  
      Args:
         lr_init(float): init learning rate
         total_epochs(int): total epoch of training
         steps_per_epoch(int): steps of one epoch
  
      Returns:
         np.array, learning rate array
      """
      lr_each_step = []
      half_epoch = total_epochs // 2
      for i in range(total_epochs * steps_per_epoch):
          if i < half_epoch:
              lr_each_step.append(lr_init)
          else:
              lr_each_step.append(lr_init / (1.1 ** (i - half_epoch)))
      learning_rate = np.array(lr_each_step).astype(np.float32)
      return learning_rate
  