org.simmetrics.metrics

Class Identity<T>

java.lang.Object

org.simmetrics.metrics.Identity<T>

Type Parameters:

T - type of token

All Implemented Interfaces:

Distance<T>, Metric<T>

public final class Identity<T>
extends Object
implements Metric<T>, Distance<T>

Identity similarity and distance metric that returns a distance of 0.0 and similarity 1.0 when the inputs are equals, and vice-versa when they're not.

similarity(a,b) = equals(a,b) ? 1.0f : 0.0f
distance(a,b) = equals(a,b) ? 0.0f : 1.0f

This class is immutable and thread-safe.

Constructor Summary

Constructors

Constructor and Description
Identity()

Method Summary

Modifier and Type	Method and Description
float	compare(T a, T b) Measures the similarity between a and b.
float	distance(T a, T b) Measures the distance between a and b.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Identity

public Identity()

Method Detail

compare

public float compare(T a,
                     T b)

Description copied from interface: Metric

Measures the similarity between a and b. The measurement results in a value between 0 and 1 inclusive. A value of 0.0 indicates that a and b are dissimilar, a value of 1.0 indicates they are similar.

Specified by:

compare in interface Metric<T>

Parameters:

a - object a to compare

b - object b to compare

Returns:

a value between 0 and 1 inclusive indicating similarity

distance

public float distance(T a,
                      T b)

Description copied from interface: Distance

Measures the distance between a and b. The measurement results in a non-negative value. A value of 0.0 indicates that a and b are similar.

Specified by:

distance in interface Distance<T>

Parameters:

a - object a to compare

b - object b to compare

Returns:

a non-negative value

toString

public String toString()

Overrides:

toString in class Object