org.tribuo.impl

Class BinaryFeaturesExample<T extends Output<T>>

java.lang.Object

org.tribuo.Example<T>

org.tribuo.impl.BinaryFeaturesExample<T>

Type Parameters:

T - The output type.

All Implemented Interfaces:

Serializable, Iterable<Feature>

public final class BinaryFeaturesExample<T extends Output<T>>
extends Example<T>

An Example backed by a single array of feature names. This implementation is modeled after ArrayExample but does not store feature values because it assumes only binary features - i.e., features with a feature value of 1.0. The following methods throw an UnsupportedOperationException:

• densify(List)
• densify(FeatureMap)
• set(Feature)
• transform(TransformerMap)

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_SIZE
protected String[]	featureNames
protected int	size

Fields inherited from class org.tribuo.Example

DEFAULT_METADATA_SIZE, DEFAULT_WEIGHT, metadata, NAME, output, weight

Constructor Summary

Constructors

Constructor and Description
BinaryFeaturesExample(Example<T> other) Copy constructor.
BinaryFeaturesExample(T output) Constructs an example from an output.
BinaryFeaturesExample(T output, Example<U> other, float weight) Clones an example's features, but uses the supplied output and weight.
BinaryFeaturesExample(T output, float weight) Constructs an example from an output and a weight.
BinaryFeaturesExample(T output, float weight, int initialSize) Constructs an example from an output and a weight, with an initial size for the feature arrays.
BinaryFeaturesExample(T output, float weight, Map<String,Object> metadata) Constructs an example from an output, a weight and the metadata.
BinaryFeaturesExample(T output, List<? extends Feature> features) Constructs an example from an output and a list of features.
BinaryFeaturesExample(T output, Map<String,Object> metadata) Constructs an example from an output and the metadata.
BinaryFeaturesExample(T output, String[] names) Constructs an example from an output and an array of names.

Method Summary

Modifier and Type	Method and Description
void	add(Feature feature) Adds a feature to this example.
void	add(String name) Adds a single feature with a value of 1.
void	addAll(Collection<? extends Feature> features) Adds a collection of features to this example.
void	canonicalize(FeatureMap featureMap) Reassigns feature name Strings in the Example to point to those in the FeatureMap.
static void	checkIsBinary(Feature feature)
BinaryFeaturesExample<T>	copy() Returns a deep copy of this Example.
protected void	densify(FeatureMap fMap) Converts all implicit zeros into explicit zeros based on the supplied feature map.
void	densify(List<String> featureList) Converts all implicit zeros into explicit zeros based on the supplied feature names.
boolean	equals(Object o)
protected void	growArray() Grows the backing arrays by size+1.
protected void	growArray(int minCapacity) Grows the backing arrays storing the names.
int	hashCode()
static boolean	isBinary(Feature feature)
Iterator<Feature>	iterator()
Feature	lookup(String i) Returns the Feature in this Example which has the supplied name, if it's present.
protected int	newCapacity(int minCapacity) Returns a capacity at least as large as the given minimum capacity.
void	reduceByName(Merger merger) Merges features with the same name using the supplied Merger.
void	removeFeatures(List<Feature> featureList) Removes all features in this list from the Example.
void	set(Feature feature) Overwrites the feature with the matching name.
int	size() Return how many features are in this example.
protected void	sort() Sorts the feature list to maintain the lexicographic order invariant.
String	toString()
void	transform(TransformerMap transformerMap) Transforms this example by applying the transformations from the supplied TransformerMap.
boolean	validateExample() Checks the example to see if all the feature names are unique, the feature values are not NaN, and there is at least one feature.

Methods inherited from class org.tribuo.Example

containsMetadata, getMetadata, getMetadataValue, getOutput, getWeight, setMetadataValue, setWeight

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

DEFAULT_SIZE

public static final int DEFAULT_SIZE

See Also:

Constant Field Values

featureNames

protected String[] featureNames

size

protected int size

Constructor Detail

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             float weight,
                             int initialSize)

Constructs an example from an output and a weight, with an initial size for the feature arrays.

Parameters:

output - The output.

weight - The weight.

initialSize - The initial size of the feature arrays.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             float weight,
                             Map<String,Object> metadata)

Constructs an example from an output, a weight and the metadata.

Parameters:

output - The output.

weight - The weight.

metadata - The metadata.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             float weight)

Constructs an example from an output and a weight.

Parameters:

output - The output.

weight - The example weight.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             Map<String,Object> metadata)

Constructs an example from an output and the metadata.

Parameters:

output - The output.

metadata - The metadata.

BinaryFeaturesExample

public BinaryFeaturesExample(T output)

Constructs an example from an output.

Parameters:

output - The output.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             String[] names)

Constructs an example from an output and an array of names. This is currently the most efficient constructor.

Parameters:

output - The output.

names - The feature names.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             List<? extends Feature> features)

Constructs an example from an output and a list of features. This constructor will throw an IllegalArgumentException if any of the features have a feature value that does not equal 1.0.

Parameters:

output - The output (e.g., label) of the example

features - The list of features.

BinaryFeaturesExample

public BinaryFeaturesExample(Example<T> other)

Copy constructor. This constructor will throw an IllegalArgumentException if any of the features have a feature value that does not equal 1.0.

Parameters:

other - The example to copy.

BinaryFeaturesExample

public BinaryFeaturesExample(T output,
                             Example<U> other,
                             float weight)

Clones an example's features, but uses the supplied output and weight.

Type Parameters:

U - The output type of the other example.

Parameters:

output - The output to use.

other - The features to use.

weight - The weight to use.

Method Detail

add

public void add(String name)

Adds a single feature with a value of 1.

Parameters:

name - The name of the feature.

isBinary

public static boolean isBinary(Feature feature)

checkIsBinary

public static void checkIsBinary(Feature feature)

add

public void add(Feature feature)

Adds a feature to this example. This method will throw an IllegalArgumentException if any of the features have a feature value that does not equal 1.0.

Specified by:

add in class Example<T extends Output<T>>

Parameters:

feature - The feature to add to this example.

addAll

public void addAll(Collection<? extends Feature> features)

Adds a collection of features to this example. This method will throw an IllegalArgumentException if any of the features have a feature value that does not equal 1.0.

Specified by:

addAll in class Example<T extends Output<T>>

Parameters:

features - The features to add to this example.

growArray

protected void growArray(int minCapacity)

Grows the backing arrays storing the names.

Parameters:

minCapacity - The new minimum capacity required.

growArray

protected void growArray()

Grows the backing arrays by size+1.

newCapacity

protected int newCapacity(int minCapacity)

Returns a capacity at least as large as the given minimum capacity. Returns the current capacity increased by 50% if that suffices. Will not return a capacity greater than MAX_ARRAY_SIZE unless the given minimum capacity is greater than MAX_ARRAY_SIZE.

Parameters:

minCapacity - the desired minimum capacity

Returns:

The new capacity.

Throws:

OutOfMemoryError - if minCapacity is less than zero

sort

protected void sort()

Sorts the feature list to maintain the lexicographic order invariant.

Specified by:

sort in class Example<T extends Output<T>>

size

public int size()

Description copied from class: Example

Return how many features are in this example.

Specified by:

size in class Example<T extends Output<T>>

Returns:

The number of features.

removeFeatures

public void removeFeatures(List<Feature> featureList)

Description copied from class: Example

Removes all features in this list from the Example.

Specified by:

removeFeatures in class Example<T extends Output<T>>

Parameters:

featureList - Features to remove from this Example.

validateExample

public boolean validateExample()

Description copied from class: Example

Checks the example to see if all the feature names are unique, the feature values are not NaN, and there is at least one feature.

Specified by:

validateExample in class Example<T extends Output<T>>

Returns:

true if the example is valid.

copy

public BinaryFeaturesExample<T> copy()

Description copied from class: Example

Returns a deep copy of this Example.

Specified by:

copy in class Example<T extends Output<T>>

Returns:

A deep copy of this example.

lookup

public Feature lookup(String i)

Description copied from class: Example

Returns the Feature in this Example which has the supplied name, if it's present.

Overrides:

lookup in class Example<T extends Output<T>>

Parameters:

i - The feature name to lookup.

Returns:

The feature object.

set

public void set(Feature feature)

Description copied from class: Example

Overwrites the feature with the matching name.

Throws IllegalArgumentException if there isn't a feature with that name in this example.

Specified by:

set in class Example<T extends Output<T>>

Parameters:

feature - The new feature value.

transform

public void transform(TransformerMap transformerMap)

Description copied from class: Example

Transforms this example by applying the transformations from the supplied TransformerMap.

Can be overridden for performance reasons.

Overrides:

transform in class Example<T extends Output<T>>

Parameters:

transformerMap - The transformations to apply.

reduceByName

public void reduceByName(Merger merger)

Description copied from class: Example

Merges features with the same name using the supplied Merger.

Specified by:

reduceByName in class Example<T extends Output<T>>

Parameters:

merger - this parameter is ignored because we do not store feature values in this class. So, the 'merging' can be thought of as a logical AND.

densify

public void densify(List<String> featureList)

Description copied from class: Example

Converts all implicit zeros into explicit zeros based on the supplied feature names.

Specified by:

densify in class Example<T extends Output<T>>

Parameters:

featureList - A *sorted* list of feature names.

densify

protected void densify(FeatureMap fMap)

Description copied from class: Example

Converts all implicit zeros into explicit zeros based on the supplied feature map.

Overrides:

densify in class Example<T extends Output<T>>

Parameters:

fMap - The feature map to use for densification.

iterator

public Iterator<Feature> iterator()

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

canonicalize

public void canonicalize(FeatureMap featureMap)

Description copied from class: Example

Reassigns feature name Strings in the Example to point to those in the FeatureMap. This significantly reduces memory allocation. It is called when an Example is added to a MutableDataset, and should not be called outside of that context as it may interact unexpectedly with HashedFeatureMap.

Specified by:

canonicalize in class Example<T extends Output<T>>

Parameters:

featureMap - The feature map containing canonical feature names.