org.lenskit.knn.user

Class UserSnapshot

java.lang.Object

org.lenskit.knn.user.UserSnapshot

All Implemented Interfaces:

java.io.Serializable

@Shareable
 @ThreadSafe
 @DefaultProvider(value=UserSnapshot.Builder.class)
public class UserSnapshot
extends java.lang.Object
implements java.io.Serializable

User snapshot used by SnapshotNeighborFinder.

Since:

2.1

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UserSnapshot.Builder

Method Summary

Modifier and Type	Method and Description
LongSet	getItemUsers(long item)
Long2DoubleMap	getNormalizedUserVector(long user) Get a user vector normalized for similarity computations.
Long2DoubleMap	getUserVector(long user) Get a user vector normalized for score computations.

Methods inherited from class java.lang.Object

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

Method Detail

getUserVector

public Long2DoubleMap getUserVector(long user)

Get a user vector normalized for score computations.

Parameters:

user - The user ID.

Returns:

The normalized user rating vector (with ScoreNormalizer).

getNormalizedUserVector

public Long2DoubleMap getNormalizedUserVector(long user)

Get a user vector normalized for similarity computations.

Returns:

The normalized user rating vector (with SimilarityNormalizer).

getItemUsers

public LongSet getItemUsers(long item)