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

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

public class HaversineFunction
extends ValueSource

Calculate the Haversine formula (distance) between any two points on a sphere Takes in four value sources: (latA, lonA); (latB, lonB).

Assumes the value sources are in radians unless

See http://en.wikipedia.org/wiki/Great-circle_distance and http://en.wikipedia.org/wiki/Haversine_formula for the actual formula and also http://www.movable-type.co.uk/scripts/latlong.html

Constructor Summary

HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius)

HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius, boolean convertToRads)

Method Summary

void	createWeight(Map context, IndexSearcher searcher)
String	description()
protected double	distance(int doc, FunctionValues p1DV, FunctionValues p2DV)
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

Constructor Detail

HaversineFunction

public HaversineFunction(MultiValueSource p1,
                         MultiValueSource p2,
                         double radius)

HaversineFunction

public HaversineFunction(MultiValueSource p1,
                         MultiValueSource p2,
                         double radius,
                         boolean convertToRads)

Method Detail

name

protected String name()

distance

protected double distance(int doc,
                          FunctionValues p1DV,
                          FunctionValues p2DV)

Parameters:

doc - The doc to score

Returns:

The haversine distance formula

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