"""Modified from https://github.com/rwightman/pytorch-image- | |
models/blob/master/timm/models/layers/drop.py.""" | |
import torch | |
from torch import nn | |
class DropPath(nn.Module): | |
"""Drop paths (Stochastic Depth) per sample (when applied in main path of | |
residual blocks). | |
Args: | |
drop_prob (float): Drop rate for paths of model. Dropout rate has | |
to be between 0 and 1. Default: 0. | |
""" | |
def __init__(self, drop_prob=0.): | |
super(DropPath, self).__init__() | |
self.drop_prob = drop_prob | |
self.keep_prob = 1 - drop_prob | |
def forward(self, x): | |
if self.drop_prob == 0. or not self.training: | |
return x | |
shape = (x.shape[0], ) + (1, ) * ( | |
x.ndim - 1) # work with diff dim tensors, not just 2D ConvNets | |
random_tensor = self.keep_prob + torch.rand( | |
shape, dtype=x.dtype, device=x.device) | |
random_tensor.floor_() # binarize | |
output = x.div(self.keep_prob) * random_tensor | |
return output | |