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import torch.nn as nn
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from itertools import repeat
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from typing import Iterable
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def _ntuple(n):
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"""Copy item to be a tuple with n length (Implemented as timm)
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"""
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def parse(x):
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if isinstance(x, Iterable):
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return x
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else:
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return tuple(repeat(x, n))
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return parse
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to_2tuple = _ntuple(2)
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to_ntuple = _ntuple
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class DropPath(nn.Module):
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"""Stochasticly zero channels of data.(Implemented as timm)
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"""
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def __init__(self, drop=0.5, scale=True):
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super().__init__()
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self.drop = drop
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self.scale = scale
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def forward(self, x):
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return self.drop_path(x, self.drop, self.training, self.scale)
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def drop_path(self, x, drop=0.5, training=True, scale=True):
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if drop == 0. or not training:
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return x
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drop_p = 1 - drop
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shape = (x.shape[0],) + (1,) * (x.ndim - 1)
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random_tensor = x.new_empty(shape).bernoulli_(drop_p)
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if drop_p > 0. and scale:
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random_tensor.div_(drop_p)
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return x * random_tensor |