Tensorflow implemention is different from the pytorch version

[pdoublerainbow]

Hi, thanks for your job. When I read the code, I find possible problem here,
This is the tensorflow version:
tf.tensordot(errors_sorted, tf.stop_gradient(grad), 1, name="loss_class_{}".format(c))
This is ht pytorch version:
loss = torch.dot(F.relu(errors_sorted), Variable(grad))
The tensorflow version have no no Nonlinear，but pytorch have it. I have no idea about which one is right or which one is better.
A more question here, if I want to understand submodular completely, what should I do, do you have some link or book to recommend to me.
Thanks!

[pdoublerainbow]

I have find what mistake I have made, you just need to answer the second question now. It is too stupid, I'm sorry about that.