Package elki.distance.geo

Class DimensionSelectingLatLngDistance

java.lang.Object

elki.distance.geo.DimensionSelectingLatLngDistance

All Implemented Interfaces:

Distance<NumberVector>, NumberVectorDistance<NumberVector>, PrimitiveDistance<NumberVector>, SpatialPrimitiveDistance<NumberVector>

@Reference(authors="Erich Schubert, Arthur Zimek, Hans-Peter Kriegel",
           title="Geodetic Distance Queries on R-Trees for Indexing Geographic Data",
           booktitle="Int. Symp. Advances in Spatial and Temporal Databases (SSTD\'2013)",
           url="https://doi.org/10.1007/978-3-642-40235-7_9",
           bibkey="DBLP:conf/ssd/SchubertZK13")
public class DimensionSelectingLatLngDistance
extends java.lang.Object
implements SpatialPrimitiveDistance<NumberVector>, NumberVectorDistance<NumberVector>

Distance function for 2D vectors in Latitude, Longitude form.

The input data must be in degrees (not radians), and the output distance will be in meters (see EarthModel.distanceDeg(double, double, double, double)).

This implementation allows index accelerated queries using R*-trees (by providing a point-to-rectangle minimum distance).

Reference:

Erich Schubert, Arthur Zimek, Hans-Peter Kriegel
Geodetic Distance Queries on R-Trees for Indexing Geographic Data
Int. Symp. Advances in Spatial and Temporal Databases (SSTD'2013)

Since:

0.4.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DimensionSelectingLatLngDistance.Par	Parameterization class.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) int	dimlat	Latitude dimension.
(package private) int	dimlng	Longitude dimension.
(package private) EarthModel	model	Earth model used.

Constructor Summary

Constructors

Constructor	Description
DimensionSelectingLatLngDistance(int dimlat, int dimlng, EarthModel model)	Constructor.

Method Summary

Modifier and Type	Method	Description
double	distance(NumberVector o1, NumberVector o2)	Computes the distance between two given DatabaseObjects according to this distance function.
boolean	equals(java.lang.Object obj)
SimpleTypeInformation<? super NumberVector>	getInputTypeRestriction()	Get the input data type of the function.
int	hashCode()
boolean	isMetric()	Is this distance function metric (satisfy the triangle inequality)
double	minDist(SpatialComparable mbr1, SpatialComparable mbr2)	Computes the distance between the two given MBRs according to this distance function.

Methods inherited from class java.lang.Object

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

Methods inherited from interface elki.distance.Distance

isSquared, isSymmetric

Methods inherited from interface elki.distance.SpatialPrimitiveDistance

instantiate

Field Detail

dimlat

final int dimlat

Latitude dimension.

dimlng

final int dimlng

Longitude dimension.

model

final EarthModel model

Earth model used.

Constructor Detail

DimensionSelectingLatLngDistance

public DimensionSelectingLatLngDistance(int dimlat,
                                        int dimlng,
                                        EarthModel model)

Constructor.

Parameters:

dimlat - Dimension storing the latitude

dimlng - Dimension storing the longitude

model - Earth model

Method Detail

distance

public double distance(NumberVector o1,
                       NumberVector o2)

Description copied from interface: PrimitiveDistance

Computes the distance between two given DatabaseObjects according to this distance function.

Specified by:

distance in interface NumberVectorDistance<NumberVector>

Specified by:

distance in interface PrimitiveDistance<NumberVector>

Parameters:

o1 - first DatabaseObject

o2 - second DatabaseObject

Returns:

the distance between two given DatabaseObjects according to this distance function

minDist

public double minDist(SpatialComparable mbr1,
                      SpatialComparable mbr2)

Description copied from interface: SpatialPrimitiveDistance

Computes the distance between the two given MBRs according to this distance function.

Specified by:

minDist in interface SpatialPrimitiveDistance<NumberVector>

Parameters:

mbr1 - the first MBR object

mbr2 - the second MBR object

Returns:

the distance between the two given MBRs according to this distance function

getInputTypeRestriction

public SimpleTypeInformation<? super NumberVector> getInputTypeRestriction()

Description copied from interface: Distance

Get the input data type of the function.

Specified by:

getInputTypeRestriction in interface Distance<NumberVector>

Specified by:

getInputTypeRestriction in interface PrimitiveDistance<NumberVector>

Returns:

Type restriction

isMetric

public boolean isMetric()

Description copied from interface: Distance

Is this distance function metric (satisfy the triangle inequality)

Specified by:

isMetric in interface Distance<NumberVector>

Returns:

true when metric.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object