es.uam.eps.ir.ranksys.nn.sim

Interface Similarity

All Known Implementing Classes:

ItemSimilarity, SetCosineItemSimilarity, SetCosineSimilarity, SetCosineUserSimilarity, SetJaccardItemSimilarity, SetJaccardSimilarity, SetJaccardUserSimilarity, SetSimilarity, UserSimilarity, VectorCosineItemSimilarity, VectorCosineSimilarity, VectorCosineUserSimilarity, VectorJaccardItemSimilarity, VectorJaccardSimilarity, VectorJaccardUserSimilarity, VectorSimilarity

public interface Similarity

Generic similarity for fast data. This is the interface that is under the hood of the user and item similarities. It is does not need be symmetric.

Author:

Saúl Vargas (saul.vargas@uam.es)

Method Summary

Modifier and Type	Method and Description
Stream<Tuple2id>	similarElems(int idx) Returns all the users/items having a similarity greater than 0, together with the value of the similarity.
IntToDoubleFunction	similarity(int idx) Returns a function that returns the similarity with the user/item.
default double	similarity(int idx1, int idx2) Returns the similarity between two users/items.

Method Detail

similarity

IntToDoubleFunction similarity(int idx)

Returns a function that returns the similarity with the user/item.

Parameters:

idx - index of the user/item

Returns:

function that returns the similarity with the index

similarity

default double similarity(int idx1,
                          int idx2)

Returns the similarity between two users/items.

Parameters:

idx1 - index of user/item

idx2 - index of user/item

Returns:

similarity between the pair

similarElems

Stream<Tuple2id> similarElems(int idx)

Returns all the users/items having a similarity greater than 0, together with the value of the similarity.

Parameters:

idx - index of user/item

Returns:

stream of index-similarity pairs