Class ExactMatchDistance
 java.lang.Object

 org.cicirello.sequences.distance.ExactMatchDistance

 All Implemented Interfaces:
SequenceDistanceMeasurer
,SequenceDistanceMeasurerDouble
public final class ExactMatchDistance extends Object implements SequenceDistanceMeasurer
ExactMatch distance (or Hamming Distance) of a pair of nonbinary strings (or more generally sequences) is the number of sequence (or string) positions where the two sequences differ. This class supports comparison of Java String objects, as well as comparisons of arrays of any of Java's eight primitive types, and arrays of any object type. It is the count of the number of positions for which the two sequences contain different elements.
Most other implementations of Hamming distance require the two strings to be of the same length. Ours does not. If the two sequences (i.e., arrays or Strings) are of different lengths, then the difference in length affects distance. E.g., although "abbd" is a distance of 1 from "abcd" since they differ in one position, "abbd" is a distance of 4 from "abcdefg" (the one difference, plus the three extra characters).
Runtime: O(n), where n is the length of the shorter of the two sequences.
If your sequences are guaranteed not to have duplicates, and to contain the same set of elements, then consider instead using the
ExactMatchDistance
class, which assumes permutations of the integers from 0 to N1.Exact match distance was introduced specifically for permutations in:
S. Ronald, "More distance functions for orderbased encodings," in Proc. IEEE CEC. IEEE Press, 1998, pp. 558–563.


Constructor Summary
Constructors Constructor Description ExactMatchDistance()
Constructs the distance measurer as specified in the class documentation.

Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description int
distance(boolean[] s1, boolean[] s2)
Measures the distance between two arrays.int
distance(byte[] s1, byte[] s2)
Measures the distance between two arrays.int
distance(char[] s1, char[] s2)
Measures the distance between two arrays.int
distance(double[] s1, double[] s2)
Measures the distance between two arrays.int
distance(float[] s1, float[] s2)
Measures the distance between two arrays.int
distance(int[] s1, int[] s2)
Measures the distance between two arrays.int
distance(long[] s1, long[] s2)
Measures the distance between two arrays.int
distance(short[] s1, short[] s2)
Measures the distance between two arrays.int
distance(Object[] s1, Object[] s2)
Measures the distance between two arrays of objects.int
distance(String s1, String s2)
Measures the distance between two Strings.<T> int
distance(List<T> s1, List<T> s2)
Measures the distance between two lists of objects.



Method Detail

distance
public int distance(int[] s1, int[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(long[] s1, long[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(short[] s1, short[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(byte[] s1, byte[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(char[] s1, char[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(boolean[] s1, boolean[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(double[] s1, double[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(float[] s1, float[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public int distance(String s1, String s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two Strings. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First String.s2
 Second String. Returns:
 distance between s1 and s2

distance
public int distance(Object[] s1, Object[] s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two arrays of objects. The objects in the arrays must be of a class that has overridden the Object.equals method. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Parameters:
s1
 First array.s2
 Second array. Returns:
 distance between s1 and s2

distance
public <T> int distance(List<T> s1, List<T> s2)
Description copied from interface:SequenceDistanceMeasurer
Measures the distance between two lists of objects. The objects in the lists must be of a class that has overridden the Object.equals method. Specified by:
distance
in interfaceSequenceDistanceMeasurer
 Type Parameters:
T
 Type of List elements. Parameters:
s1
 First list.s2
 Second list. Returns:
 distance between s1 and s2

