PyTorch - How to get learning rate during training?
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Solution 1
For only one parameter group like in the example you've given, you can use this function and call it during training to get the current learning rate:
def get_lr(optimizer):
for param_group in optimizer.param_groups:
return param_group['lr']
Solution 2
Alternatively, you may use an lr_scheduler
along with your optimizer and simply call the built-in lr_scheduler.get_lr()
method.
Here is an example:
my_optimizer = torch.optim.Adam( my_model.parameters(),
lr = 0.001,
weight_decay = 0.002)
my_lr_scheduler = torch.optim.lr_scheduler.StepLR( my_optimizer,
step_size = 50,
gamma = 0.1)
# train
...
my_optimizer.step()
my_lr_scheduler.step()
# get learning rate
my_lr = my_lr_scheduler.get_lr()
# or
my_lr = my_lr_scheduler.optimizer.param_groups[0]['lr']
The added benefit for using lr_scheduler
is more controls on changing lr over time; lr_decay, etc.
For lr_scheduler args, refer to pytorch docs.
Author by
Admin
Updated on July 09, 2022Comments
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Admin almost 2 years
While training, I'd like to know the value of learning_rate. What should I do?
It's my code, like this:
my_optimizer = torch.optim.SGD(my_model.parameters(), lr=0.001, momentum=0.99, weight_decay=2e-3)
Thank you.