Lesson 5 MovieLens - EmbeddingDot forward function

(Derek Liang) #1

The following code is from lession 5.

I don’t understand why forward function that returns of type [torch.cuda.FloatTensor of size 32 (GPU 0)] based on the input mini batch users, and movies size 64. It contains only 32 distinct values. I am not sure what the value represents.

I am trying to visualize in the callab_filter.xlsx. If I choose 32 users, and 32 movies, I will get cells size 32 x 32. How does the forward function related to the spreadsheet? Shouldn’t the output be Tensor of size 32 x 32 in the forward function?

class EmbeddingDot(nn.Module):
    def __init__(self, n_users, n_movies):
        self.u = nn.Embedding(n_users, n_factors)
        self.m = nn.Embedding(n_movies, n_factors)
    def forward(self, cats, conts):
        users,movies = cats[:,0],cats[:,1]
        u,m = self.u(users),self.m(movies)
        return (u*m).sum(1)