全局平均池化---torch实现

# target output size of 5x7
m = nn.AdaptiveAvgPool2d((5,7))
input = torch.randn(1, 64, 8, 9)
output = m(input)

# output.shape=(1,64,5,7)

# target output size of 7x7 (square)
m = nn.AdaptiveAvgPool2d(7)
input = torch.randn(1, 64, 10, 9)
output = m(input)

# output.shape=(1,64,7,7)

# target output size of 10x7
m = nn.AdaptiveMaxPool2d((None, 7))
input = torch.randn(1, 64, 10, 9)
output = m(input)

output.shape=(1,64,10,7)