de.lmu.ifi.dbs.elki.index.projected

Class LngLatAsECEFIndex<O extends NumberVector>

java.lang.Object

de.lmu.ifi.dbs.elki.index.projected.ProjectedIndex<O,O>

de.lmu.ifi.dbs.elki.index.projected.LngLatAsECEFIndex<O>

Type Parameters:

O - Object type

All Implemented Interfaces:

Index, KNNIndex<O>, RangeIndex<O>, RKNNIndex<O>, Result

public class LngLatAsECEFIndex<O extends NumberVector>
extends ProjectedIndex<O,O>

Index a 2d data set (consisting of Lng/Lat pairs) by using a projection to 3D coordinates (WGS-86 to ECEF).

Earth-Centered, Earth-Fixed (ECEF) is a 3D coordinate system, sometimes also referred to as XYZ, that uses 3 cartesian axes. The center is at the earths center of mass, the z axis points to the north pole. X axis is to the prime meridan at the equator (so latitude 0, longitude 0), and the Y axis is orthogonal going to the east (latitude 0, longitude 90°E).

The Euclidean distance in this coordinate system is a lower bound for the great-circle distance, and Euclidean coordinates are supposedly easier to index.

Note: this index will only support the distance function LngLatDistanceFunction, as it uses a projection that will map data according to this great circle distance. If the query hint "exact" is set, it will not be used.

Since:

0.6.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LngLatAsECEFIndex.Factory<O extends NumberVector> Index factory.

Nested classes/interfaces inherited from class de.lmu.ifi.dbs.elki.index.projected.ProjectedIndex

ProjectedIndex.ProjectedKNNQuery, ProjectedIndex.ProjectedRangeQuery, ProjectedIndex.ProjectedRKNNQuery

Field Summary

Fields inherited from class de.lmu.ifi.dbs.elki.index.projected.ProjectedIndex

inner, kmulti, norefine, proj, refinements, relation, view

Constructor Summary

Constructors

Constructor and Description
LngLatAsECEFIndex(Relation<? extends O> relation, Projection<O,O> proj, Relation<O> view, Index inner, boolean norefine) Constructor.

Method Summary

Modifier and Type	Method and Description
KNNQuery<O>	getKNNQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a KNN query object for the given distance query and k.
java.lang.String	getLongName() A "pretty" name for the result, for use in titles, captions and menus.
RangeQuery<O>	getRangeQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a range query object for the given distance query and k.
RKNNQuery<O>	getRKNNQuery(DistanceQuery<O> distanceQuery, java.lang.Object... hints) Get a KNN query object for the given distance query and k.
java.lang.String	getShortName() A short name for the result, useful for file names.

Methods inherited from class de.lmu.ifi.dbs.elki.index.projected.ProjectedIndex

initialize, logStatistics

Methods inherited from class java.lang.Object

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

Constructor Detail

LngLatAsECEFIndex

public LngLatAsECEFIndex(Relation<? extends O> relation,
                         Projection<O,O> proj,
                         Relation<O> view,
                         Index inner,
                         boolean norefine)

Constructor.

Parameters:

relation - Relation to index.

proj - Projection to use.

view - View to use.

inner - Index to wrap.

norefine - Refinement disable flag.

Method Detail

getLongName

public java.lang.String getLongName()

Description copied from interface: Result

A "pretty" name for the result, for use in titles, captions and menus.

Specified by:

getLongName in interface Result

Overrides:

getLongName in class ProjectedIndex<O extends NumberVector,O extends NumberVector>

Returns:

result name

getShortName

public java.lang.String getShortName()

Description copied from interface: Result

A short name for the result, useful for file names.

Specified by:

getShortName in interface Result

Overrides:

getShortName in class ProjectedIndex<O extends NumberVector,O extends NumberVector>

Returns:

result name

getKNNQuery

public KNNQuery<O> getKNNQuery(DistanceQuery<O> distanceQuery,
                               java.lang.Object... hints)

Description copied from interface: KNNIndex

Get a KNN query object for the given distance query and k. This function MAY return null, when the given distance is not supported!

Specified by:

getKNNQuery in interface KNNIndex<O extends NumberVector>

Overrides:

getKNNQuery in class ProjectedIndex<O extends NumberVector,O extends NumberVector>

Parameters:

distanceQuery - Distance query

hints - Hints for the optimizer

Returns:

KNN Query object or null

getRangeQuery

public RangeQuery<O> getRangeQuery(DistanceQuery<O> distanceQuery,
                                   java.lang.Object... hints)

Description copied from interface: RangeIndex

Get a range query object for the given distance query and k. This function MAY return null, when the given distance is not supported!

Specified by:

getRangeQuery in interface RangeIndex<O extends NumberVector>

Overrides:

getRangeQuery in class ProjectedIndex<O extends NumberVector,O extends NumberVector>

Parameters:

distanceQuery - Distance query

hints - Hints for the optimizer

Returns:

KNN Query object or null

getRKNNQuery

public RKNNQuery<O> getRKNNQuery(DistanceQuery<O> distanceQuery,
                                 java.lang.Object... hints)

Description copied from interface: RKNNIndex

Get a KNN query object for the given distance query and k. This function MAY return null, when the given distance is not supported!

Specified by:

getRKNNQuery in interface RKNNIndex<O extends NumberVector>

Overrides:

getRKNNQuery in class ProjectedIndex<O extends NumberVector,O extends NumberVector>

Parameters:

distanceQuery - Distance query

hints - Hints for the optimizer

Returns:

KNN Query object or null