Method recommend

implicit/ann/annoy.py:148–227

(
        self,
        userid,
        user_items,
        N=10,
        filter_already_liked_items=True,
        filter_items=None,
        recalculate_user=False,
        items=None,
    )

        return ids, 1 - (scores**2) / 2

    def recommend(
        self,
        userid,
        user_items,
        N=10,
        filter_already_liked_items=True,
        filter_items=None,
        recalculate_user=False,
        items=None,
    ):
        if (filter_already_liked_items or recalculate_user) and not isinstance(
            user_items, csr_matrix
        ):
            raise ValueError("user_items needs to be a CSR sparse matrix")

        if items is not None and self.approximate_recommend:
            raise NotImplementedError("using a 'items' list with ANN search isn't supported")

        if not self.approximate_recommend:
            return self.model.recommend(
                userid,
                user_items,
                N=N,
                filter_already_liked_items=filter_already_liked_items,
                filter_items=filter_items,
                recalculate_user=recalculate_user,
                items=items,
            )

        # batch computation isn't supported by annoy, fallback to looping over items
        if not np.isscalar(userid):
            return _batch_call(
                self.recommend,
                userid,
                user_items=user_items,
                N=N,
                filter_already_liked_items=filter_already_liked_items,
                filter_items=filter_items,
                recalculate_user=recalculate_user,
                items=items,
            )

        # support recalculate_user if possible (TODO: come back to this since its a bit of a hack)
        if hasattr(self.model, "+_user_factor"):
            user = self.model._user_factor(userid, user_items, recalculate_user)  # pylint: disable=protected-access
        elif recalculate_user:
            raise NotImplementedError(f"recalculate_user isn't supported with {self.model}")
        else:
            user = self.model.user_factors[userid]
            if implicit.gpu.HAS_CUDA and isinstance(user, implicit.gpu.Matrix):
                user = user.to_numpy()

        # calculate the top N items, removing the users own liked items from
        # the results
        count = N
        if filter_items:
            count += len(filter_items)
            filter_items = np.array(filter_items)