PyTorch学习variable

Posted 2021-06-07 My heart will go ~~

本节主要放置variable的应用代码

import torch
from torch.autograd import Variable

tensor=torch.FloatTensor([[1,2],[3,4]])#tensor不能反向传播
variable=Variable(tensor,requires_grad=True)#true：可以反向传播。所以网络中都要用variable

t_out=torch.mean(tensor*tensor)#x^2求平均
v_out=torch.mean(variable*variable)

v_out.backward()#误差的反向传递
#1/4 *sum(var*var)
print(variable.grad)#反向传递之后的更新值[0.5  1  1.5  2]
print(variable.data)#variable中的data
print(variable.data.numpy())#var.data相当于tensor