org.grouplens.lenskit.knn.user

Class SnapshotNeighborFinder

java.lang.Object

org.grouplens.lenskit.knn.user.SnapshotNeighborFinder

All Implemented Interfaces:

NeighborFinder

@ThreadSafe
public class SnapshotNeighborFinder
extends Object
implements NeighborFinder

A neighborhood finder that has a snapshot of the rating data for efficiency. This is built by backing a LiveNeighborFinder with a BinaryRatingDAO.

Since:

2.1

Constructor Summary

Constructors

Constructor and Description
SnapshotNeighborFinder(UserSnapshot snap, UserSimilarity sim, UserHistorySummarizer sum, UserVectorNormalizer norm, Threshold thresh)

Method Summary

Modifier and Type	Method and Description
Iterable<Neighbor>	getCandidateNeighbors(UserHistory<? extends Event> user, LongSet items) Get potential neighbors for a particular user.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SnapshotNeighborFinder

@Inject
public SnapshotNeighborFinder(UserSnapshot snap,
                                      UserSimilarity sim,
                                      UserHistorySummarizer sum,
                                      UserVectorNormalizer norm,
                                      @UserSimilarityThreshold
                                      Threshold thresh)

Method Detail

getCandidateNeighbors

public Iterable<Neighbor> getCandidateNeighbors(UserHistory<? extends Event> user,
                                                LongSet items)

Description copied from interface: NeighborFinder

Get potential neighbors for a particular user.

Specified by:

getCandidateNeighbors in interface NeighborFinder

Parameters:

user - The user whose neighbors are wanted.

items - The items that the client needs to be able to score or recommend.

Returns:

A collection of potential neighbors for user. This collection may include neighbors that are not useful for scoring any item in items; the item set is just to help the neighbor finder guide its search if relevant.