de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants
Class TopologicalSplit<E extends SpatialEntry>

java.lang.Object
  de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.TopologicalSplit<E>

 class TopologicalSplit<E extends SpatialEntry>
extends Object

Encapsulates the required parameters for a topological split of a R*-Tree.

Author:

Elke Achtert

Field Summary

private int	bestSorting Indicates whether the sorting according to maximal or to minimal value has been used for choosing the split axis and split point.
private List<E>	maxSorting The entries sorted according to their max values of their MBRs.
private List<E>	minSorting The entries sorted according to their min values of their MBRs.
private int	splitAxis The split axis.
private int	splitPoint The index of the split point.

Constructor Summary

TopologicalSplit(List<E> entries, int minEntries)
Creates a new Split object.

Method Summary

private void	chooseSplitAxis(List<E> entries, int minEntries) Chooses a split axis.
private void	chooseSplitPoint(int minEntries) Chooses a split axis.
int	getBestSorting() Returns whether the sorting according to maximal or to minimal value has been used for choosing the split axis and split point.
List<E>	getMaxSorting() Returns the entries to be split sorted according to their max values of their MBRs.
List<E>	getMinSorting() Returns the entries to be split sorted according to their min values of their MBRs.
int	getSplitAxis() Returns the split axis.
int	getSplitPoint() Returns the split point.
private HyperBoundingBox	mbr(List<E> entries, int from, int to) Computes and returns the mbr of the specified nodes, only the nodes between from and to index are considered.

Methods inherited from class java.lang.Object

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

Field Detail

splitAxis

private int splitAxis

The split axis.

splitPoint

private int splitPoint

The index of the split point.

bestSorting

private int bestSorting

Indicates whether the sorting according to maximal or to minimal value has been used for choosing the split axis and split point.

maxSorting

private List<E extends SpatialEntry> maxSorting

The entries sorted according to their max values of their MBRs.

minSorting

private List<E extends SpatialEntry> minSorting

The entries sorted according to their min values of their MBRs.

Constructor Detail

TopologicalSplit

public TopologicalSplit(List<E> entries,
                        int minEntries)

Creates a new Split object.

Parameters:

entries - the entries to be split

minEntries - number of minimum entries in the node to be split

Method Detail

getSplitAxis

public int getSplitAxis()

Returns the split axis.

Returns:

the split axis

getSplitPoint

public int getSplitPoint()

Returns the split point.

Returns:

the split point

getMaxSorting

public List<E> getMaxSorting()

Returns the entries to be split sorted according to their max values of their MBRs.

Returns:

the entries sorted according to their max values of their MBRs

getMinSorting

public List<E> getMinSorting()

Returns the entries to be split sorted according to their min values of their MBRs.

Returns:

the entries sorted according to their min values of their MBRs

getBestSorting

public int getBestSorting()

Returns whether the sorting according to maximal or to minimal value has been used for choosing the split axis and split point.

Returns:

SpatialComparator.MIN if the sorting according to minimal value has been used, SpatialComparator.MAX otherwise

chooseSplitAxis

private void chooseSplitAxis(List<E> entries,
                             int minEntries)

Chooses a split axis.

Parameters:

entries - the entries to be split

minEntries - number of minimum entries in the node to be split

chooseSplitPoint

private void chooseSplitPoint(int minEntries)

Chooses a split axis.

Parameters:

minEntries - number of minimum entries in the node to be split

mbr

private HyperBoundingBox mbr(List<E> entries,
                             int from,
                             int to)

Computes and returns the mbr of the specified nodes, only the nodes between from and to index are considered.

Parameters:

entries - the array of nodes

from - the start index

to - the end index

Returns:

the mbr of the specified nodes