ivory.lsh.data
Class Signature

java.lang.Object
  ivory.lsh.data.Signature

All Implemented Interfaces:

Comparable, Writable, WritableComparable

Direct Known Subclasses:

MinhashSignature, NBitSignature, SixtyFourBitSignature

public abstract class Signature
extends Object
implements WritableComparable

Abstract class for signatures.

Author:

ferhanture

Constructor Summary

Signature()

Signature(int size)

Signature(Signature p)

Method Summary

static Signature	createSignature(Class subClass, int size)
int	getLongestPrefix(Signature signature)
abstract Signature	getSubSignature(int start, int end)
abstract Signature	getSubSignature(int start, int end, Signature subSign)
abstract int	hammingDistance(Signature signature)
abstract int	hammingDistance(Signature signature, int threshold)
abstract Signature	perm(ArrayListOfIntsWritable permutation)
abstract void	perm(ArrayListOfIntsWritable permutation, Signature permSign)
abstract int	size()
abstract String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.io.Writable

readFields, write

Methods inherited from interface java.lang.Comparable

compareTo

Constructor Detail

Signature

public Signature()

Signature

public Signature(int size)

Signature

public Signature(Signature p)

Method Detail

createSignature

public static Signature createSignature(Class subClass,
                                        int size)

getLongestPrefix

public int getLongestPrefix(Signature signature)

getSubSignature

public abstract Signature getSubSignature(int start,
                                          int end)

getSubSignature

public abstract Signature getSubSignature(int start,
                                          int end,
                                          Signature subSign)

hammingDistance

public abstract int hammingDistance(Signature signature)

Parameters:

signature -

Returns:

compute hamming distance between this object and signature.

hammingDistance

public abstract int hammingDistance(Signature signature,
                                    int threshold)

Parameters:

signature -

threshold -

Returns:

compute hamming distance between this object and signature. early terminate if distance exceeds threshold.

perm

public abstract Signature perm(ArrayListOfIntsWritable permutation)

Parameters:

permutation -

Returns:

permute this object w.r.t permutation object and return permuted signature

perm

public abstract void perm(ArrayListOfIntsWritable permutation,
                          Signature permSign)

Parameters:

permutation - permute this object w.r.t permutation object and save permuted signature in permSign

size

public abstract int size()

toString

public abstract String toString()

Overrides:

toString in class Object