StaticRatings Class Reference

Array-based storage for rating data. More...

Inheritance diagram for StaticRatings:

List of all members.

Public Member Functions
override void	Add (int user_id, int item_id, float rating)
	Add float-valued rating to the collection.
virtual void	Add (int user_id, int item_id, byte rating)
	Add byte-valued rating to the collection.
void	Add (float item)
void	Clear ()
bool	Contains (float item)
void	CopyTo (float[] array, int index)
virtual float	Get (int user_id, int item_id, ICollection< int > indexes)
	Directly access rating by user and item.
int	GetIndex (int user_id, int item_id)
	Get index for a given user and item.
int	GetIndex (int user_id, int item_id, ICollection< int > indexes)
	Get index for given user and item.
ISet< int >	GetItems (IList< int > indices)
	Get all items that are referenced by a given list of indices.
override void	GetObjectData (SerializationInfo info, StreamingContext context)
ISet< int >	GetUsers (IList< int > indices)
	Get all users that are referenced by a given list of indices.
int	IndexOf (float item)
virtual void	InitScale ()
	Initialize the Scale property.
void	Insert (int index, float item)
bool	Remove (float item)
override void	RemoveAt (int index)
override void	RemoveItem (int item_id)
	Remove all events related to a given item.
override void	RemoveUser (int user_id)
	Remove all events related to a given user.
	StaticRatings ()
	default constructor
	StaticRatings (int size)
	StaticRatings (SerializationInfo info, StreamingContext context)
virtual bool	TryGet (int user_id, int item_id, out float rating)
	Try to retrieve a rating for a given user-item combination.
virtual bool	TryGet (int user_id, int item_id, ICollection< int > indexes, out float rating)
	Try to retrieve a rating for a given user-item combination.
bool	TryGetIndex (int user_id, int item_id, out int index)
	Try to get the index for given user and item.
bool	TryGetIndex (int user_id, int item_id, ICollection< int > indexes, out int index)
	Try to get the index for given user and item.
Protected Member Functions
void	UpdateCountsAndIndices (ISet< int > users, ISet< int > items)
	update user- and item-wise counts and indices
Protected Attributes
IList< IList< int > >	by_item
	Indices organized by item.
IList< IList< int > >	by_user
	Indices organized by user.
IList< int >	count_by_item
	field for storing the count per item
IList< int >	count_by_user
	field for storing the count per user
int	pos = 0
	The position where the next rating will be stored.
IList< float >	Values
Properties
IList< int >	AllItems [get]
	all item IDs in the dataset
IList< int >	AllUsers [get]
	all user IDs in the dataset
float	Average [get]
	average rating in the dataset
IList< IList< int > >	ByItem [get]
	indices by item
IList< IList< int > >	ByUser [get]
	indices by user
override int	Count [get]
	the number of interaction events in the dataset
IList< int >	CountByItem [get]
	count by item
IList< int >	CountByUser [get]
	count by user
bool	IsReadOnly [get]
IList< int >	Items [get, set]
	the item entries
int	MaxItemID [get, set]
	the maximum item ID in the dataset
int	MaxUserID [get, set]
	the maximum user ID in the dataset
IList< int >	RandomIndex [get]
	get a randomly ordered list of all indices
RatingScale	Scale [get, set]
	information about the scale of the ratings in the dataset
virtual float	this[int index] [get, set]
virtual float	this[int user_id, int item_id] [get]
	Directly access rating by user and item.
IList< int >	Users [get, set]
	the user entries

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Detailed Description

Array-based storage for rating data.

Very memory-efficient.

This data structure does NOT support incremental updates.

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Constructor & Destructor Documentation

StaticRatings

(

)

[inline]

default constructor

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Member Function Documentation

override void Add	(	int	user_id,
		int	item_id,
		float	rating
	)		[inline, virtual]

Add float-valued rating to the collection.

Parameters:

user_id	the user ID
item_id	the item ID
rating	the rating

Reimplemented from Ratings.

Reimplemented in StaticByteRatings.

virtual void Add	(	int	user_id,
		int	item_id,
		byte	rating
	)		[inline, virtual, inherited]

Add byte-valued rating to the collection.

Parameters:

user_id	the user ID
item_id	the item ID
rating	the rating

Implements IRatings.

Reimplemented in StaticByteRatings.

virtual float Get	(	int	user_id,
		int	item_id,
		ICollection< int >	indexes
	)		[inline, virtual, inherited]

Directly access rating by user and item.

Parameters:

user_id	the user ID
item_id	the item ID
indexes	the indexes to look at

Returns:

the first rating encountered that matches the user ID and item ID

Implements IRatings.

Reimplemented in StaticByteRatings.

int GetIndex	(	int	user_id,
		int	item_id
	)		[inline, inherited]

Get index for a given user and item.

Parameters:

user_id	the user ID
item_id	the item ID

Returns:

the index of the first event encountered that matches the user ID and item ID

Implements IDataSet.

int GetIndex	(	int	user_id,
		int	item_id,
		ICollection< int >	indexes
	)		[inline, inherited]

Get index for given user and item.

Parameters:

user_id	the user ID
item_id	the item ID
indexes	the indexes to look at

Returns:

the index of the first event encountered that matches the user ID and item ID

Implements IDataSet.

ISet<int> GetItems

(

IList< int >

indices

)

[inline, inherited]

Get all items that are referenced by a given list of indices.

Parameters:

indices

the indices to take into account

Returns:

all items referenced by the list of indices

Implements IDataSet.

ISet<int> GetUsers

(

IList< int >

indices

)

[inline, inherited]

Get all users that are referenced by a given list of indices.

Parameters:

indices

the indices to take into account

Returns:

all users referenced by the list of indices

Implements IDataSet.

virtual void InitScale

(

)

[inline, virtual, inherited]

Initialize the Scale property.

Implements IRatings.

Reimplemented in StaticByteRatings.

override void RemoveItem

(

int

item_id

)

[inline, virtual]

Remove all events related to a given item.

Parameters:

item_id

the item ID

Reimplemented from Ratings.

override void RemoveUser

(

int

user_id

)

[inline, virtual]

Remove all events related to a given user.

Parameters:

user_id

the user ID

Reimplemented from Ratings.

virtual bool TryGet	(	int	user_id,
		int	item_id,
		out float	rating
	)		[inline, virtual, inherited]

Try to retrieve a rating for a given user-item combination.

Parameters:

user_id	the user ID
item_id	the item ID
rating	will contain the first rating encountered that matches the user ID and item ID

Returns:

true if a rating was found for the user and item

Implements IRatings.

Reimplemented in StaticByteRatings.

virtual bool TryGet	(	int	user_id,
		int	item_id,
		ICollection< int >	indexes,
		out float	rating
	)		[inline, virtual, inherited]

Try to retrieve a rating for a given user-item combination.

Parameters:

user_id	the user ID
item_id	the item ID
indexes	the indexes to look at
rating	will contain the first rating encountered that matches the user ID and item ID

Returns:

true if a rating was found for the user and item

Implements IRatings.

Reimplemented in StaticByteRatings.

bool TryGetIndex	(	int	user_id,
		int	item_id,
		out int	index
	)		[inline, inherited]

Try to get the index for given user and item.

Parameters:

user_id	the user ID
item_id	the item ID
index	will contain the index of the first event encountered that matches the user ID and item ID

Returns:

true if an index was found for the user and item

Implements IDataSet.

bool TryGetIndex	(	int	user_id,
		int	item_id,
		ICollection< int >	indexes,
		out int	index
	)		[inline, inherited]

Try to get the index for given user and item.

Parameters:

user_id	the user ID
item_id	the item ID
indexes	the indexes to look at
index	will contain the index of the first event encountered that matches the user ID and item ID

Returns:

true if an index was found for the user and item

Implements IDataSet.

void UpdateCountsAndIndices	(	ISet< int >	users,
		ISet< int >	items
	)		[inline, protected, inherited]

update user- and item-wise counts and indices

Parameters:

users	the modified users
items	the modified itemsItems.

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Member Data Documentation

IList<IList<int> > by_item [protected, inherited]

Indices organized by item.

IList<IList<int> > by_user [protected, inherited]

Indices organized by user.

IList<int> count_by_item [protected, inherited]

field for storing the count per item

IList<int> count_by_user [protected, inherited]

field for storing the count per user

int pos = 0 [protected]

The position where the next rating will be stored.

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Property Documentation

IList<int> AllItems [get, inherited]

all item IDs in the dataset

Implements IDataSet.

IList<int> AllUsers [get, inherited]

all user IDs in the dataset

Implements IDataSet.

float Average [get, inherited]

average rating in the dataset

Implements IRatings.

IList<IList<int> > ByItem [get, inherited]

indices by item

Should be implemented as a lazy data structure

Implements IDataSet.

IList<IList<int> > ByUser [get, inherited]

indices by user

Should be implemented as a lazy data structure

Implements IDataSet.

override int Count [get]

the number of interaction events in the dataset

Reimplemented from DataSet.

IList<int> CountByItem [get, inherited]

count by item

Should be implemented as a lazy data structure

Implements IDataSet.

IList<int> CountByUser [get, inherited]

count by user

Should be implemented as a lazy data structure

Implements IDataSet.

IList<int> Items [get, set, inherited]

the item entries

Implements IDataSet.

int MaxItemID [get, set, inherited]

the maximum item ID in the dataset

Implements IDataSet.

int MaxUserID [get, set, inherited]

the maximum user ID in the dataset

Implements IDataSet.

IList<int> RandomIndex [get, inherited]

get a randomly ordered list of all indices

Should be implemented as a lazy data structure

Implements IDataSet.

RatingScale Scale [get, set, inherited]

information about the scale of the ratings in the dataset

Implements IRatings.

virtual float this[int user_id, int item_id] [get, inherited]

Directly access rating by user and item.

Parameters:

user_id	the user ID
item_id	the item ID

the rating value for the given user and item

Implements IRatings.

Reimplemented in StaticByteRatings.

IList<int> Users [get, set, inherited]

the user entries

Implements IDataSet.

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The documentation for this class was generated from the following file:

• StaticRatings.cs