Assert error in BPR without user/item features

[zzzrbx]

I'm using precision_at_k from lightFM library with the code below.

    lightfm_model = LightFM(loss="bpr", no_components=25, random_state=0)

    lightfm_model.fit(interactions=coo_matrix((np.ones(len(training)), (training["user"], training["product"]))), num_threads=20)

    print lightfm_model.user_embeddings.shape 
    print lightfm_model.item_embeddings.shape

    print (precision_at_k(model=lightfm_model,
                              train_interactions=coo_matrix((np.ones(len(training)), (training["user"], training["product"]))),
                              test_interactions=coo_matrix((np.ones(len(test)), (test["user"], test["product"]))),
                              k=5,
                              user_features=None,
                              item_features=None) )

the size of user and item embeddings is correct (25 for both) but I'm getting:

assert self.user_embeddings.shape[0] >= user_features.shape[1]

AssertionError

Notice that I'm not using user/item features.

[maciejkula]

This assertion is meant to prevent you from passing interaction matrices of incompatible shapes into fit and predict. In this case, I think your test matrix has a larger first dimension than your train matrix, and so there are some users in the test set that were not in the original train set.

Can you check that this is not the case?

[zzzrbx]

silly mistake. I think you are right :)

…

On Fri, Dec 16, 2016 at 4:45 PM, maciejkula ***@***.***> wrote: This assertion is meant to prevent you from passing interaction matrices of incompatible shapes into fit and predict. In this case, I think your test matrix has a larger first dimension than your train matrix, and so there are some users in the test set that were not in the original train set. Can you check that this is not the case? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#133 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AWJKwyejmIm5lziE8PUg6jfxCOvgwRAsks5rIsA9gaJpZM4LPQ2c> .

[maciejkula]

Arguably the library should be more informative about what's wrong. I'll look into providing a better error message.