org.apache.solr.search.function.distance
Class VectorDistanceFunction

java.lang.Object
  org.apache.lucene.queries.function.ValueSource
      org.apache.solr.search.function.distance.VectorDistanceFunction

Direct Known Subclasses:

SquaredEuclideanFunction

public class VectorDistanceFunction
extends ValueSource

Calculate the p-norm for a Vector. See http://en.wikipedia.org/wiki/Lp_space

Common cases:

• 0 = Sparseness calculation
• 1 = Manhattan distance
• 2 = Euclidean distance
• Integer.MAX_VALUE = infinite norm

See Also:

for the special case

Field Summary

protected float	oneOverPower
protected float	power
protected MultiValueSource	source1
protected MultiValueSource	source2

Constructor Summary

VectorDistanceFunction(float power, MultiValueSource source1, MultiValueSource source2)

Method Summary

void	createWeight(Map context, IndexSearcher searcher)
String	description()
protected double	distance(int doc, FunctionValues dv1, FunctionValues dv2) Calculate the distance
boolean	equals(Object o)
FunctionValues	getValues(Map context, AtomicReaderContext readerContext)
int	hashCode()
protected String	name()

Methods inherited from class org.apache.lucene.queries.function.ValueSource

getSortField, newContext, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

source1

protected MultiValueSource source1

source2

protected MultiValueSource source2

power

protected float power

oneOverPower

protected float oneOverPower

Constructor Detail

VectorDistanceFunction

public VectorDistanceFunction(float power,
                              MultiValueSource source1,
                              MultiValueSource source2)

Method Detail

name

protected String name()

distance

protected double distance(int doc,
                          FunctionValues dv1,
                          FunctionValues dv2)

Calculate the distance

Parameters:

doc - The current doc

dv1 - The values from the first MultiValueSource

dv2 - The values from the second MultiValueSource

Returns:

The distance

getValues

public FunctionValues getValues(Map context,
                                AtomicReaderContext readerContext)
                         throws IOException

Specified by:

getValues in class ValueSource

Throws:

IOException

createWeight

public void createWeight(Map context,
                         IndexSearcher searcher)
                  throws IOException

Overrides:

createWeight in class ValueSource

Throws:

IOException

equals

public boolean equals(Object o)

Specified by:

equals in class ValueSource

hashCode

public int hashCode()

Specified by:

hashCode in class ValueSource

description

public String description()

Specified by:

description in class ValueSource