org.tribuo

Class ImmutableFeatureMap

java.lang.Object

org.tribuo.FeatureMap

org.tribuo.ImmutableFeatureMap

All Implemented Interfaces:

Serializable, Iterable<VariableInfo>

Direct Known Subclasses:

HashedFeatureMap

public class ImmutableFeatureMap
extends FeatureMap
implements Serializable

ImmutableFeatureMap is used when unknown features should not be added to the FeatureMap.

It's also got feature ids as those are only generated for immutable maps.

The feature ids are generated by sorting the feature names by the String comparator. This ensures that any Example with sorted names has sorted int ids, even if some of those features are unobserved. This is an extremely important property of Features, Examples and ImmutableFeatureMap.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<Integer,VariableIDInfo>	idMap The map from id numbers to the feature infos.
protected int	size The number of features.

Fields inherited from class org.tribuo.FeatureMap

m

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ImmutableFeatureMap() Constructs a new empty immutable feature map.
	ImmutableFeatureMap(FeatureMap map) Constructs a new immutable version which is a deep copy of the supplied feature map, generating new ID numbers.
	ImmutableFeatureMap(List<VariableInfo> infoList) Constructs a new immutable feature map copying the supplied variable infos and generating appropriate ID numbers.

Method Summary

Modifier and Type	Method and Description
static Map<String,VariableIDInfo>	generateIDs(FeatureMap map) Generates the feature ids by sorting the features with the String comparator, then sequentially numbering them.
static Map<String,VariableIDInfo>	generateIDs(List<? extends VariableInfo> list) Generates the feature ids by sorting the features with the String comparator, then sequentially numbering them.
VariableIDInfo	get(int id) Gets the VariableIDInfo for this id number.
VariableIDInfo	get(String name) Gets the VariableIDInfo for this name.
int	getID(String name) Gets the id number for this feature, returns -1 if it's unknown.
int	size() Returns the number of features in the domain.

Methods inherited from class org.tribuo.FeatureMap

iterator, keySet, toReadableString, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

idMap

protected final Map<Integer,VariableIDInfo> idMap

The map from id numbers to the feature infos.

size

protected int size

The number of features.

Constructor Detail

ImmutableFeatureMap

public ImmutableFeatureMap(FeatureMap map)

Constructs a new immutable version which is a deep copy of the supplied feature map, generating new ID numbers.

The new id numbers will be the same as the old ones (if they existed) assuming this is a regular feature map.

Parameters:

map - The map to copy.

ImmutableFeatureMap

public ImmutableFeatureMap(List<VariableInfo> infoList)

Constructs a new immutable feature map copying the supplied variable infos and generating appropriate ID numbers.

Parameters:

infoList - The variable infos.

ImmutableFeatureMap

protected ImmutableFeatureMap()

Constructs a new empty immutable feature map.

Used for mocking feature domains in tests.

Method Detail

get

public VariableIDInfo get(int id)

Gets the VariableIDInfo for this id number. Returns null if it's unknown.

Parameters:

id - The id number to lookup.

Returns:

The VariableInfo, or null.

get

public VariableIDInfo get(String name)

Gets the VariableIDInfo for this name. Returns null if it's unknown.

Overrides:

get in class FeatureMap

Parameters:

name - The name to lookup.

Returns:

The VariableInfo, or null.

getID

public int getID(String name)

Gets the id number for this feature, returns -1 if it's unknown.

Parameters:

name - The name of the feature.

Returns:

A non-negative integer if the feature is known, -1 otherwise.

size

public int size()

Description copied from class: FeatureMap

Returns the number of features in the domain.

Overrides:

size in class FeatureMap

Returns:

The number of features.

generateIDs

public static Map<String,VariableIDInfo> generateIDs(FeatureMap map)

Generates the feature ids by sorting the features with the String comparator, then sequentially numbering them.

Parameters:

map - A feature map to convert.

Returns:

A map from feature names to VariableIDInfo objects.

generateIDs

public static Map<String,VariableIDInfo> generateIDs(List<? extends VariableInfo> list)

Generates the feature ids by sorting the features with the String comparator, then sequentially numbering them.

Parameters:

list - A list of VariableInfos to generate a map from.

Returns:

A map from feature names to VariableIDInfo objects.