22 lines
802 B
Python
22 lines
802 B
Python
# Copyright (c) Meta Platforms, Inc. and affiliates.
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# All rights reserved.
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# This source code is licensed under the license found in the
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# LICENSE file in the root directory of this source tree.
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import math
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def adjust_learning_rate(optimizer, epoch, args):
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"""Decay the learning rate with half-cycle cosine after warmup"""
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if epoch < args.warmup_epochs:
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lr = args.lr * epoch / args.warmup_epochs
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else:
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lr = args.min_lr + (args.lr - args.min_lr) * 0.5 * \
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(1. + math.cos(math.pi * (epoch - args.warmup_epochs) / (args.epochs - args.warmup_epochs)))
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for param_group in optimizer.param_groups:
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if "lr_scale" in param_group:
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param_group["lr"] = lr * param_group["lr_scale"]
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else:
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param_group["lr"] = lr
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return lr
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