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

Interface FastPreferenceData<U,I>

Type Parameters:

U - type of the users

I - type of the items

All Superinterfaces:

FastItemIndex<I>, FastUserIndex<U>, ItemIndex<I>, PreferenceData<U,I>, UserIndex<U>

All Known Subinterfaces:

FastPointWisePreferenceData<U,I>

All Known Implementing Classes:

AbstractCODECPreferenceData, AbstractFastPreferenceData, BinaryCODECPreferenceData, IteratorsAbstractFastPreferenceData, RatingCODECPreferenceData, SimpleFastPreferenceData, StreamsAbstractFastPreferenceData, TransposedPreferenceData

public interface FastPreferenceData<U,I>
extends PreferenceData<U,I>, FastUserIndex<U>, FastItemIndex<I>

Fast version of PreferenceData, where preferences for users and items are stored internally by the indexes provided by FastUserIndex and FastItemIndex.

Author:

Saúl Vargas (saul.vargas@uam.es)

Method Summary

Modifier and Type	Method and Description
Stream<? extends IdxPref>	getIidxPreferences(int iidx) Gets the preferences of an item.
it.unimi.dsi.fastutil.ints.IntIterator	getIidxUidxs(int iidx) Returns the user idxs of the preferences for an item.
it.unimi.dsi.fastutil.doubles.DoubleIterator	getIidxVs(int iidx) Returns the user values of the preferences for an item.
IntStream	getIidxWithPreferences() Returns a stream of item indexes for which users have preferences.
it.unimi.dsi.fastutil.ints.IntIterator	getUidxIidxs(int uidx) Returns the item idxs of the preferences of a user.
Stream<? extends IdxPref>	getUidxPreferences(int uidx) Gets the preferences of a user.
it.unimi.dsi.fastutil.doubles.DoubleIterator	getUidxVs(int uidx) Returns the item values of the preferences of a user.
IntStream	getUidxWithPreferences() Returns a stream of user indexes who have preferences for items.
int	numItems(int uidx) Returns the number of items for which the user has preference for.
int	numUsers(int iidx) Returns the number of users who have a preference for the item.
boolean	useIteratorsPreferentially() Use methods returning IntIterator or DoubleIterator over streams of IdxPref?

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

getItemPreferences, getItemsWithPreferences, getUserPreferences, getUsersWithPreferences, numItems, numItemsWithPreferences, numPreferences, numUsers, numUsersWithPreferences

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

Method Detail

numUsers

int numUsers(int iidx)

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

Parameters:

iidx - item index

Returns:

number of users who have a preference for the item

numItems

int numItems(int uidx)

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

Parameters:

uidx - user index

Returns:

number of items for which the user has preference for

getUidxWithPreferences

IntStream getUidxWithPreferences()

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

Returns:

a stream of user indexes who have preferences for items

getIidxWithPreferences

IntStream getIidxWithPreferences()

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

Returns:

a stream of item indexes for which users have preferences

getUidxPreferences

Stream<? extends IdxPref> getUidxPreferences(int uidx)

Gets the preferences of a user.

Parameters:

uidx - user index

Returns:

preferences of the user

getIidxPreferences

Stream<? extends IdxPref> getIidxPreferences(int iidx)

Gets the preferences of an item.

Parameters:

iidx - item index

Returns:

preferences of the item

getUidxIidxs

it.unimi.dsi.fastutil.ints.IntIterator getUidxIidxs(int uidx)

Returns the item idxs of the preferences of a user.

Parameters:

uidx - user index

Returns:

iterator of the idxs of the items

getUidxVs

it.unimi.dsi.fastutil.doubles.DoubleIterator getUidxVs(int uidx)

Returns the item values of the preferences of a user.

Parameters:

uidx - user index

Returns:

iterator of the values of the items

getIidxUidxs

it.unimi.dsi.fastutil.ints.IntIterator getIidxUidxs(int iidx)

Returns the user idxs of the preferences for an item.

Parameters:

iidx - item index

Returns:

iterator of the idxs of the users.

getIidxVs

it.unimi.dsi.fastutil.doubles.DoubleIterator getIidxVs(int iidx)

Returns the user values of the preferences for an item.

Parameters:

iidx - item index

Returns:

iterator of the values of the users

useIteratorsPreferentially

boolean useIteratorsPreferentially()

Use methods returning IntIterator or DoubleIterator over streams of IdxPref?

Returns:

yes/no