29 lines
953 B
Python
29 lines
953 B
Python
from abc import ABC, abstractmethod
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import numpy as np
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import torch
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from torch.optim.lr_scheduler import LambdaLR, LRScheduler
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from tianshou.highlevel.config import SamplingConfig
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from tianshou.utils.string import ToStringMixin
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class LRSchedulerFactory(ToStringMixin, ABC):
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"""Factory for the creation of a learning rate scheduler."""
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@abstractmethod
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def create_scheduler(self, optim: torch.optim.Optimizer) -> LRScheduler:
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pass
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class LRSchedulerFactoryLinear(LRSchedulerFactory):
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def __init__(self, sampling_config: SamplingConfig):
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self.sampling_config = sampling_config
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def create_scheduler(self, optim: torch.optim.Optimizer) -> LRScheduler:
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max_update_num = (
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np.ceil(self.sampling_config.step_per_epoch / self.sampling_config.step_per_collect)
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* self.sampling_config.num_epochs
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)
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return LambdaLR(optim, lr_lambda=lambda epoch: 1 - epoch / max_update_num)
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