Solved by Nikronic in post #2 
              
              
                Hi, 
There is no mathematical difference between them, except the dimension of input data. 
nn.BatchNorm2d only accepts 4D inputs while nn.BatchNorm1d accepts 2D or 3D inputs. And because of that, in features which has been constructed of nn.Conv2d layers, inputs are [batch, ch, h, w] (4D) we need B…