The Pytorch version is : 0.4.1
The pow function is used as follows:
The para is a Parameter object with size [out, int, h]-----my custom net layer
band = para[:,:,2].reshape(num,1,1).repeat(1,h,w)
ratio = torch.tensor(np.sqrt(np.log(2)/2)/np.pi) * (torch.pow(2,band)+1)/(torch.pow(2,band)-1)
when  loss.backward() is executed it raise:
RuntimeError: the derivative for pow is not implemented
Besides, I test the code in Windows OS. Is it the reason?