org.aksw.limes.core.measures.measure.string

Class CosineMeasure

java.lang.Object

org.aksw.limes.core.measures.measure.AMeasure

org.aksw.limes.core.measures.measure.string.StringMeasure

org.aksw.limes.core.measures.measure.string.CosineMeasure

All Implemented Interfaces:

IMeasure, IStringMeasure

public class CosineMeasure
extends StringMeasure

Author:

Axel-C. Ngonga Ngomo (ngonga@informatik.uni-leipzig.de)

Constructor Summary

Constructors

Constructor and Description
CosineMeasure()

Method Summary

Modifier and Type	Method and Description
boolean	computableViaOverlap() Returns true if this similarity function can be computed just via the getSimilarity(overlag, lengthA, lengthB)
int	getAlpha(int xTokensNumber, int yTokensNumber, double threshold) Threshold for the positional filtering
int	getMidLength(int tokensNumber, double threshold) Theshold for the length of the tokens to be indexed
String	getName() Returns name of a measure.
int	getPrefixLength(int tokensNumber, double threshold) Length of prefix to consider when mapping the input string with other strings.
double	getRuntimeApproximation(double mappingSize) Returns the runtime approximation of a measure.
double	getSimilarity(Instance instance1, Instance instance2, String property1, String property2) Returns the similarity between two instances, given their corresponding properties.
double	getSimilarity(int overlap, int lengthA, int lengthB) Returns the similarity of two strings given their length and the overlap.
double	getSimilarity(Object object1, Object object2) Returns the similarity between two objects.
double	getSimilarityChar(Object a, Object b)
double	getSizeFilteringThreshold(int tokensNumber, double threshold)
String	getType() Returns type of a measure.

Methods inherited from class java.lang.Object

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

Constructor Detail

CosineMeasure

public CosineMeasure()

Method Detail

getSimilarityChar

public double getSimilarityChar(Object a,
                                Object b)

getSimilarity

public double getSimilarity(Object object1,
                            Object object2)

Description copied from interface: IMeasure

Returns the similarity between two objects.

Returns:

The similarity of the objects

getType

public String getType()

Description copied from interface: IMeasure

Returns type of a measure.

Returns:

The runtime of the measure

getSimilarity

public double getSimilarity(Instance instance1,
                            Instance instance2,
                            String property1,
                            String property2)

Description copied from interface: IMeasure

Returns the similarity between two instances, given their corresponding properties.

Returns:

The similarity of the instances

getName

public String getName()

Description copied from interface: IMeasure

Returns name of a measure.

Returns:

Measure name as a string

getSimilarity

public double getSimilarity(int overlap,
                            int lengthA,
                            int lengthB)

Description copied from interface: IStringMeasure

Returns the similarity of two strings given their length and the overlap. Useful when these values are known so that no computation of known values have to be carried out anew

Parameters:

overlap - Overlap of strings A and B

lengthA - Length of A

lengthB - Length of B

Returns:

Similarity of A and B

computableViaOverlap

public boolean computableViaOverlap()

Description copied from interface: IStringMeasure

Returns true if this similarity function can be computed just via the getSimilarity(overlag, lengthA, lengthB)

Returns:

True if it's possible, else false;

getPrefixLength

public int getPrefixLength(int tokensNumber,
                           double threshold)

Description copied from interface: IStringMeasure

Length of prefix to consider when mapping the input string with other strings.

Parameters:

tokensNumber - Size of input string in

threshold - Similarity threshold

Returns:

Prefix length

getMidLength

public int getMidLength(int tokensNumber,
                        double threshold)

Description copied from interface: IStringMeasure

Theshold for the length of the tokens to be indexed

Parameters:

tokensNumber - Number of tokens of current input

threshold - Similarity threshold

Returns:

Length of tokens to be indexed

getSizeFilteringThreshold

public double getSizeFilteringThreshold(int tokensNumber,
                                        double threshold)

getAlpha

public int getAlpha(int xTokensNumber,
                    int yTokensNumber,
                    double threshold)

Threshold for the positional filtering

Parameters:

xTokensNumber - Size of the first input string

yTokensNumber - Size of the first input string

threshold - Similarity threshold

Returns:

Threshold for positional filtering

getRuntimeApproximation

public double getRuntimeApproximation(double mappingSize)

Description copied from interface: IMeasure

Returns the runtime approximation of a measure.

Returns:

The runtime of the measure