de.dfki.mycbr.core.similarity

Class StringFct

java.lang.Object

java.util.Observable

de.dfki.mycbr.core.similarity.StringFct

All Implemented Interfaces:

ISimFct, java.util.Observer

public class StringFct
extends java.util.Observable
implements ISimFct

Calculates the similarity of two strings for a given description. At the moment only syntactic equality is supported.

Author:

myCBR Team

Constructor Summary

Constructors

Constructor and Description
StringFct(Project prj, StringConfig config, StringDesc desc, java.lang.String name) Initializes this with the given description.

Method Summary

Methods

Modifier and Type	Method and Description
Similarity	calculateSimilarity(Attribute value1, Attribute value2) Calculates the similarity of the given attributes.
void	clone(AttributeDesc descNEW, boolean active) Creates a new function which is the same function as this but with a different description, namely descNEW.
StringConfig	getConfig() Returns the configuration of this function.
AttributeDesc	getDesc() Returns the description of the attributes which can be compared using this function
int	getLevenshteinAddCost()
int	getLevenshteinChangeCost()
int	getLevenshteinDelCost()
MultipleConfig	getMultipleConfig()
int	getN() Returns the parameter n for computing NGRAM similarity.
java.lang.String	getName() Returns the name of this function
Project	getProject()
boolean	isCaseSensitive() Returns whether this function is case sensitive.
boolean	isSymmetric() Returns whether this function is symmetric.
void	setCaseSensitive(boolean caseSensitive) Specifies whether this function is case sensitive.
void	setLevenshteinAddCost(int levenshteinAddCost)
void	setLevenshteinChangeCost(int levenshteinChangeCost)
void	setLevenshteinDelCost(int levenshteinDelCost)
void	setMultipleConfig(MultipleConfig mc)
void	setN(int n) Sets the parameter n for computing NGRAM similarity.
void	setName(java.lang.String name) Sets the name of this function to name
void	setSymmetric(boolean symmetric) Specifies whether this function is symmetric or not.
void	update(java.util.Observable o, java.lang.Object arg)

Methods inherited from class java.util.Observable

addObserver, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers

Methods inherited from class java.lang.Object

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

Constructor Detail

StringFct

public StringFct(Project prj,
         StringConfig config,
         StringDesc desc,
         java.lang.String name)

Initializes this with the given description.

Parameters:

desc - the description of the

Method Detail

getLevenshteinDelCost

public int getLevenshteinDelCost()

Returns:

the levenshteinDelCost

setLevenshteinDelCost

public void setLevenshteinDelCost(int levenshteinDelCost)

Parameters:

levenshteinDelCost - the levenshteinDelCost to set

getLevenshteinAddCost

public int getLevenshteinAddCost()

Returns:

the levenshteinAddCost

setLevenshteinAddCost

public void setLevenshteinAddCost(int levenshteinAddCost)

Parameters:

levenshteinAddCost - the levenshteinAddCost to set

getLevenshteinChangeCost

public int getLevenshteinChangeCost()

Returns:

the levenshteinChangeCost

setLevenshteinChangeCost

public void setLevenshteinChangeCost(int levenshteinChangeCost)

Parameters:

levenshteinChangeCost - the levenshteinChangeCost to set

calculateSimilarity

public Similarity calculateSimilarity(Attribute value1,
                             Attribute value2)
                               throws java.lang.Exception

Calculates the similarity of the given attributes. Returns null if an error occurs.

Specified by:

calculateSimilarity in interface ISimFct

Parameters:

value1 - the first value

value2 - the second value

Returns:

1.00 if the given attributes are equal, invalid similarity if an error occurs, else 0.00

Throws:

java.lang.Exception

isSymmetric

public boolean isSymmetric()

Returns whether this function is symmetric. Equalitym, NGRAM and Levenshtein similarity is always symmetric.

Specified by:

isSymmetric in interface ISimFct

Returns:

true

setSymmetric

public void setSymmetric(boolean symmetric)

Description copied from interface: ISimFct

Specifies whether this function is symmetric or not. If a function sim is symmetric, sim(q,c) = sim(c,q) should hold for all queries q and cases c this function is defined on. Else the function is asymmetric.

Specified by:

setSymmetric in interface ISimFct

Parameters:

symmetric - specifies whether this function is symmetric or not.

getConfig

public StringConfig getConfig()

Returns the configuration of this function.

Returns:

the configuration describing how to compute similarity

getN

public int getN()

Returns the parameter n for computing NGRAM similarity. N specifies the length of the substrings to be compared.

Returns:

the parameter n

setN

public void setN(int n)

Sets the parameter n for computing NGRAM similarity. N specifies the length of the substrings to be compared.

Parameters:

n - the new parameter n

isCaseSensitive

public boolean isCaseSensitive()

Returns whether this function is case sensitive.

Returns:

true, if function is case sensitive, false otherwise

setCaseSensitive

public void setCaseSensitive(boolean caseSensitive)

Specifies whether this function is case sensitive.

Parameters:

caseSensitive - true, if function is case sensitive, false otherwise

getName

public java.lang.String getName()

Description copied from interface: ISimFct

Returns the name of this function

Specified by:

getName in interface ISimFct

Returns:

the name of this function

setName

public void setName(java.lang.String name)

Description copied from interface: ISimFct

Sets the name of this function to name

Specified by:

setName in interface ISimFct

Parameters:

name - the new name of this function

getDesc

public AttributeDesc getDesc()

Description copied from interface: ISimFct

Returns the description of the attributes which can be compared using this function

Specified by:

getDesc in interface ISimFct

Returns:

the description this function belongs to

getProject

public Project getProject()

Specified by:

getProject in interface ISimFct

getMultipleConfig

public MultipleConfig getMultipleConfig()

Specified by:

getMultipleConfig in interface ISimFct

setMultipleConfig

public void setMultipleConfig(MultipleConfig mc)

Specified by:

setMultipleConfig in interface ISimFct

clone

public void clone(AttributeDesc descNEW,
         boolean active)

Description copied from interface: ISimFct

Creates a new function which is the same function as this but with a different description, namely descNEW. Assumption: this function fits the description of descNEW.

Specified by:

clone in interface ISimFct

update

public void update(java.util.Observable o,
          java.lang.Object arg)

Specified by:

update in interface java.util.Observer