# Copyright (c) 2020, Soohwan Kim. 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.
import torch
from kospeech.optim.adamp import AdamP
from kospeech.optim.radam import RAdam
from kospeech.optim.novograd import Novograd
[docs]class Optimizer(object):
"""
This is wrapper classs of torch.optim.Optimizer.
This class provides functionalities for learning rate scheduling and gradient norm clipping.
Args:
optim (torch.optim.Optimizer): optimizer object, the parameters to be optimized
should be given when instantiating the object, e.g. torch.optim.Adam, torch.optim.SGD
scheduler (kospeech.optim.lr_scheduler, optional): learning rate scheduler
scheduler_period (int, optional): timestep with learning rate scheduler
max_grad_norm (int, optional): value used for gradient norm clipping
"""
def __init__(self, optim, scheduler=None, scheduler_period=None, max_grad_norm=0):
self.optimizer = optim
self.scheduler = scheduler
self.scheduler_period = scheduler_period
self.max_grad_norm = max_grad_norm
self.count = 0
def step(self, model):
if self.max_grad_norm > 0:
torch.nn.utils.clip_grad_norm_(model.parameters(), self.max_grad_norm)
self.optimizer.step()
if self.scheduler is not None:
self.update()
self.count += 1
if self.scheduler_period == self.count:
self.scheduler = None
self.scheduler_period = 0
self.count = 0
def set_scheduler(self, scheduler, scheduler_period):
self.scheduler = scheduler
self.scheduler_period = scheduler_period
self.count = 0
def update(self):
if isinstance(self.scheduler, torch.optim.lr_scheduler.ReduceLROnPlateau):
pass
else:
self.scheduler.step()
def zero_grad(self):
self.optimizer.zero_grad()
def get_lr(self):
for g in self.optimizer.param_groups:
return g['lr']
def set_lr(self, lr):
for g in self.optimizer.param_groups:
g['lr'] = lr