I am trying to constraint the final layer of my NN to have non negative weights in the final layer, for my binary classification task ( the reason for me wanting to have non negative weights does not matter right now)

This is basically what my code looks like :

```
class Classifier(nn.Module):
def __init__(self, in_dim, hidden_dim1 , hidden_dim2 , hidden_dim3 , n_classes):
super(Classifier, self).__init__()
# other layers
self.classify = nn.Linear(hidden_dim3 , n_classes)
def forward(self, g , h ):
# other layers
hg = self.classify(h)
self.classify.weight.data = self.classify.weight.data.clamp(min=0)
hg = torch.sigmoid ( hg )
return hg
```

so am i doing this right? is this proper way of forcing the final layer to only have positive weights and therefore only looks for âpositiveâ features to do classification ?

wouldnât there be problems because sigmoid with only positive input only outputs +50% probabilities? the bias should fix this problem, right?

Note that keras has

```
tf.keras.constraints.NonNeg()
```

which does the same thing and i am trying to do that in pytorch.