smile.math.distance

Class JaccardDistance<T>

java.lang.Object

smile.math.distance.JaccardDistance<T>

All Implemented Interfaces:

java.io.Serializable, Distance<T[]>

public class JaccardDistance<T>
extends java.lang.Object
implements Distance<T[]>, java.io.Serializable

The Jaccard index, also known as the Jaccard similarity coefficient is a statistic used for comparing the similarity and diversity of sample sets. The Jaccard coefficient measures similarity between sample sets, and is defined as the size of the intersection divided by the size of the union of the sample sets. The Jaccard distance, which measures dissimilarity between sample sets, is complementary to the Jaccard coefficient and is obtained by subtracting the Jaccard coefficient from 1, or, equivalently, by dividing the difference of the sizes of the union and the intersection of two sets by the size of the union.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
JaccardDistance() Constructor.

Method Summary

Modifier and Type	Method and Description
static <T> double	d(java.util.Set<T> a, java.util.Set<T> b) Returns the Jaccard distance between sets.
double	d(T[] a, T[] b) Returns the distance measure between two objects.
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

JaccardDistance

public JaccardDistance()

Constructor.

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

d

public double d(T[] a,
                T[] b)

Description copied from interface: Distance

Returns the distance measure between two objects.

Specified by:

d in interface Distance<T[]>

d

public static <T> double d(java.util.Set<T> a,
                           java.util.Set<T> b)

Returns the Jaccard distance between sets.