es.uam.eps.ir.ranksys.fast.preference

Class SimpleFastPreferenceData<U,I>

java.lang.Object

es.uam.eps.ir.ranksys.fast.preference.AbstractFastPreferenceData<U,I>

org.ranksys.fast.preference.StreamsAbstractFastPreferenceData<U,I>

es.uam.eps.ir.ranksys.fast.preference.SimpleFastPreferenceData<U,I>

Type Parameters:

U - type of the users

I - type of the items

All Implemented Interfaces:

ItemIndex<I>, UserIndex<U>, PreferenceData<U,I>, FastItemIndex<I>, FastUserIndex<U>, FastPreferenceData<U,I>, Serializable, PointWisePreferenceData<U,I>, FastPointWisePreferenceData<U,I>

public class SimpleFastPreferenceData<U,I>
extends StreamsAbstractFastPreferenceData<U,I>
implements FastPointWisePreferenceData<U,I>, Serializable

Simple implementation of FastPreferenceData backed by nested lists.

Author:

Saúl Vargas (saul.vargas@uam.es)

See Also:

Serialized Form

Field Summary

Fields inherited from class es.uam.eps.ir.ranksys.fast.preference.AbstractFastPreferenceData

ii, iPrefFun, ui, uPrefFun

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SimpleFastPreferenceData(int numPreferences, List<List<IdxPref>> uidxList, List<List<IdxPref>> iidxList, FastUserIndex<U> uIndex, FastItemIndex<I> iIndex) Constructor with default IdxPref to IdPref converter.
protected	SimpleFastPreferenceData(int numPreferences, List<List<IdxPref>> uidxList, List<List<IdxPref>> iidxList, FastUserIndex<U> uIndex, FastItemIndex<I> iIndex, Function<IdxPref,IdPref<I>> uPrefFun, Function<IdxPref,IdPref<U>> iPrefFun) Constructor with custom IdxPref to IdPref converter.

Method Summary

Modifier and Type	Method and Description
Stream<IdxPref>	getIidxPreferences(int iidx) Gets the preferences of an item.
IntStream	getIidxWithPreferences() Returns a stream of item indexes for which users have preferences.
Optional<IdxPref>	getPreference(int uidx, int iidx) Get preference of a user for an item.
Optional<? extends IdPref<I>>	getPreference(U u, I i) Get preference of a user for an item.
Stream<IdxPref>	getUidxPreferences(int uidx) Gets the preferences of a user.
IntStream	getUidxWithPreferences() Returns a stream of user indexes who have preferences for items.
static <U,I> SimpleFastPreferenceData<U,I>	load(Stream<org.jooq.lambda.tuple.Tuple3<U,I,Double>> tuples, FastUserIndex<U> uIndex, FastItemIndex<I> iIndex) Loads a SimpleFastPreferenceData from a stream of user-item-value triples.
static <U,I,O> SimpleFastPreferenceData<U,I>	load(Stream<org.jooq.lambda.tuple.Tuple4<U,I,Double,O>> tuples, org.jooq.lambda.function.Function4<Integer,Integer,Double,O,? extends IdxPref> uIdxPrefFun, org.jooq.lambda.function.Function4<Integer,Integer,Double,O,? extends IdxPref> iIdxPrefFun, FastUserIndex<U> uIndex, FastItemIndex<I> iIndex, Function<IdxPref,IdPref<I>> uIdPrefFun, Function<IdxPref,IdPref<U>> iIdPrefFun) Loads a SimpleFastPreferenceData from a stream of user-item-value-other tuples.
int	numItems(int uidx) Returns the number of items for which the user has preference for.
int	numItemsWithPreferences() Returns the number of items with preferences.
int	numPreferences() Returns the total number of preferences
int	numUsers(int iidx) Returns the number of users who have a preference for the item.
int	numUsersWithPreferences() Returns the number of users with preferences.

Methods inherited from class org.ranksys.fast.preference.StreamsAbstractFastPreferenceData

getIidxUidxs, getIidxVs, getUidxIidxs, getUidxVs, useIteratorsPreferentially

Methods inherited from class es.uam.eps.ir.ranksys.fast.preference.AbstractFastPreferenceData

containsItem, containsUser, getAllItems, getAllUsers, getItemPreferences, getItemsWithPreferences, getUserPreferences, getUsersWithPreferences, iidx2item, item2iidx, numItems, numItems, numUsers, numUsers, uidx2user, user2uidx

Methods inherited from class java.lang.Object

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

Methods inherited from interface es.uam.eps.ir.ranksys.fast.preference.FastPreferenceData

getIidxUidxs, getIidxVs, getUidxIidxs, getUidxVs, useIteratorsPreferentially

Methods inherited from interface es.uam.eps.ir.ranksys.core.preference.PreferenceData

getItemPreferences, getItemsWithPreferences, getUserPreferences, getUsersWithPreferences, numItems, numUsers

Methods inherited from interface es.uam.eps.ir.ranksys.fast.index.FastUserIndex

containsUser, getAllUidx, getAllUsers, uidx2user, uidx2user, uidx2user, user2uidx, user2uidx, user2uidx

Methods inherited from interface es.uam.eps.ir.ranksys.core.index.UserIndex

numUsers

Methods inherited from interface es.uam.eps.ir.ranksys.fast.index.FastItemIndex

containsItem, getAllIidx, getAllItems, iidx2item, iidx2item, iidx2item, item2iidx, item2iidx, item2iidx

Methods inherited from interface es.uam.eps.ir.ranksys.core.index.ItemIndex

numItems

Constructor Detail

SimpleFastPreferenceData

protected SimpleFastPreferenceData(int numPreferences,
                                   List<List<IdxPref>> uidxList,
                                   List<List<IdxPref>> iidxList,
                                   FastUserIndex<U> uIndex,
                                   FastItemIndex<I> iIndex)

Constructor with default IdxPref to IdPref converter.

Parameters:

numPreferences - number of total preferences

uidxList - list of lists of preferences by user index

iidxList - list of lists of preferences by item index

uIndex - user index

iIndex - item index

SimpleFastPreferenceData

protected SimpleFastPreferenceData(int numPreferences,
                                   List<List<IdxPref>> uidxList,
                                   List<List<IdxPref>> iidxList,
                                   FastUserIndex<U> uIndex,
                                   FastItemIndex<I> iIndex,
                                   Function<IdxPref,IdPref<I>> uPrefFun,
                                   Function<IdxPref,IdPref<U>> iPrefFun)

Constructor with custom IdxPref to IdPref converter.

Parameters:

numPreferences - number of total preferences

uidxList - list of lists of preferences by user index

iidxList - list of lists of preferences by item index

uIndex - user index

iIndex - item index

uPrefFun - user IdxPref to IdPref converter

iPrefFun - item IdxPref to IdPref converter

Method Detail

numUsers

public int numUsers(int iidx)

Description copied from interface: FastPreferenceData

Returns the number of users who have a preference for the item.

Specified by:

numUsers in interface FastPreferenceData<U,I>

Parameters:

iidx - item index

Returns:

number of users who have a preference for the item

numItems

public int numItems(int uidx)

Description copied from interface: FastPreferenceData

Returns the number of items for which the user has preference for.

Specified by:

numItems in interface FastPreferenceData<U,I>

Parameters:

uidx - user index

Returns:

number of items for which the user has preference for

getUidxPreferences

public Stream<IdxPref> getUidxPreferences(int uidx)

Description copied from interface: FastPreferenceData

Gets the preferences of a user.

Specified by:

getUidxPreferences in interface FastPreferenceData<U,I>

Parameters:

uidx - user index

Returns:

preferences of the user

getIidxPreferences

public Stream<IdxPref> getIidxPreferences(int iidx)

Description copied from interface: FastPreferenceData

Gets the preferences of an item.

Specified by:

getIidxPreferences in interface FastPreferenceData<U,I>

Parameters:

iidx - item index

Returns:

preferences of the item

numPreferences

public int numPreferences()

Description copied from interface: PreferenceData

Returns the total number of preferences

Specified by:

numPreferences in interface PreferenceData<U,I>

Returns:

total number of preferences

getUidxWithPreferences

public IntStream getUidxWithPreferences()

Description copied from interface: FastPreferenceData

Returns a stream of user indexes who have preferences for items.

Specified by:

getUidxWithPreferences in interface FastPreferenceData<U,I>

Returns:

a stream of user indexes who have preferences for items

getIidxWithPreferences

public IntStream getIidxWithPreferences()

Description copied from interface: FastPreferenceData

Returns a stream of item indexes for which users have preferences.

Specified by:

getIidxWithPreferences in interface FastPreferenceData<U,I>

Returns:

a stream of item indexes for which users have preferences

numUsersWithPreferences

public int numUsersWithPreferences()

Description copied from interface: PreferenceData

Returns the number of users with preferences.

Specified by:

numUsersWithPreferences in interface PreferenceData<U,I>

Overrides:

numUsersWithPreferences in class AbstractFastPreferenceData<U,I>

Returns:

number of users with preferences

numItemsWithPreferences

public int numItemsWithPreferences()

Description copied from interface: PreferenceData

Returns the number of items with preferences.

Specified by:

numItemsWithPreferences in interface PreferenceData<U,I>

Overrides:

numItemsWithPreferences in class AbstractFastPreferenceData<U,I>

Returns:

number of items with preferences

getPreference

public Optional<IdxPref> getPreference(int uidx,
                                       int iidx)

Description copied from interface: FastPointWisePreferenceData

Get preference of a user for an item.

Specified by:

getPreference in interface FastPointWisePreferenceData<U,I>

Parameters:

uidx - user idx

iidx - item idx

Returns:

optional preference for item if it exists

getPreference

public Optional<? extends IdPref<I>> getPreference(U u,
                                                   I i)

Description copied from interface: PointWisePreferenceData

Get preference of a user for an item.

Specified by:

getPreference in interface PointWisePreferenceData<U,I>

Parameters:

u - user

i - item

Returns:

optional preference for item if it exists

load

public static <U,I> SimpleFastPreferenceData<U,I> load(Stream<org.jooq.lambda.tuple.Tuple3<U,I,Double>> tuples,
                                                       FastUserIndex<U> uIndex,
                                                       FastItemIndex<I> iIndex)

Loads a SimpleFastPreferenceData from a stream of user-item-value triples.

Type Parameters:

U - user type

I - item type

Parameters:

tuples - stream of user-item-value triples

uIndex - user index

iIndex - item index

Returns:

an instance of SimpleFastPreferenceData containing the data from the input stream

load

public static <U,I,O> SimpleFastPreferenceData<U,I> load(Stream<org.jooq.lambda.tuple.Tuple4<U,I,Double,O>> tuples,
                                                         org.jooq.lambda.function.Function4<Integer,Integer,Double,O,? extends IdxPref> uIdxPrefFun,
                                                         org.jooq.lambda.function.Function4<Integer,Integer,Double,O,? extends IdxPref> iIdxPrefFun,
                                                         FastUserIndex<U> uIndex,
                                                         FastItemIndex<I> iIndex,
                                                         Function<IdxPref,IdPref<I>> uIdPrefFun,
                                                         Function<IdxPref,IdPref<U>> iIdPrefFun)

Loads a SimpleFastPreferenceData from a stream of user-item-value-other tuples. It can accomodate other information, thus you need to provide sub-classes of IdxPref IdPref accomodating for this new information.

Type Parameters:

U - user type

I - item type

O - additional information type

Parameters:

tuples - stream of user-item-value-other tuples

uIdxPrefFun - converts a tuple to a user IdxPref

iIdxPrefFun - converts a tuple to a item IdxPref

uIndex - user index

iIndex - item index

uIdPrefFun - user IdxPref to IdPref converter

iIdPrefFun - item IdxPref to IdPref converter

Returns:

an instance of SimpleFastPreferenceData containing the data from the input stream