org.apache.solr.search.function.distance

Class HaversineFunction

java.lang.Object

org.apache.solr.search.function.ValueSource

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

All Implemented Interfaces:

java.io.Serializable

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

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	convertToRadians
private MultiValueSource	p1
private MultiValueSource	p2
private double	radius

Constructor Summary

Constructors

Constructor and Description
HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius)
HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius, boolean convertToRads)

Method Summary

Modifier and Type	Method and Description
void	createWeight(java.util.Map context, org.apache.lucene.search.Searcher searcher) Implementations should propagate createWeight to sub-ValueSources which can optionally store weight info in the context.
java.lang.String	description() description of field, used in explain()
protected double	distance(int doc, DocValues p1DV, DocValues p2DV)
boolean	equals(java.lang.Object o)
DocValues	getValues(java.util.Map context, org.apache.lucene.index.IndexReader reader) Gets the values for this reader and the context that was previously passed to createWeight()
int	hashCode()
protected java.lang.String	name()

Methods inherited from class org.apache.solr.search.function.ValueSource

getSortField, getValues, newContext, toString

Methods inherited from class java.lang.Object

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

Field Detail

p1

private MultiValueSource p1

p2

private MultiValueSource p2

convertToRadians

private boolean convertToRadians

radius

private double radius

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 java.lang.String name()

distance

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

Parameters:

doc - The doc to score

p1DV -

p2DV -

Returns:

The haversine distance formula

getValues

public DocValues getValues(java.util.Map context,
                           org.apache.lucene.index.IndexReader reader)
                    throws java.io.IOException

Description copied from class: ValueSource

Gets the values for this reader and the context that was previously passed to createWeight()

Overrides:

getValues in class ValueSource

Throws:

java.io.IOException

createWeight

public void createWeight(java.util.Map context,
                         org.apache.lucene.search.Searcher searcher)
                  throws java.io.IOException

Description copied from class: ValueSource

Implementations should propagate createWeight to sub-ValueSources which can optionally store weight info in the context. The context object will be passed to getValues() where this info can be retrieved.

Overrides:

createWeight in class ValueSource

Throws:

java.io.IOException

equals

public boolean equals(java.lang.Object o)

Specified by:

equals in class ValueSource

hashCode

public int hashCode()

Specified by:

hashCode in class ValueSource

description

public java.lang.String description()

Description copied from class: ValueSource

description of field, used in explain()

Specified by:

description in class ValueSource