org.apache.commons.math3.utils
Class RecordSegmentSearchIndex

java.lang.Object
  org.apache.commons.math3.utils.AbstractSearchIndex
      org.apache.commons.math3.utils.RecordSegmentSearchIndex

All Implemented Interfaces:

ISearchIndex

public class RecordSegmentSearchIndex
extends AbstractSearchIndex

Search index algorithm with previous index computation storage. This allows, in case of multiple calls in a close neighborhood (stencil with 4 points) to optimize the search by memorizing the last index found and search around it (+/- 2 points).

Since:

2.3.1

Version:

$Id: RecordSegmentSearchIndex.java 12338 2015-02-12 15:38:38Z maggiorani $

Author:

Sophie Laurens

Concurrency :

immutable

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.commons.math3.utils.ISearchIndex

ISearchIndex.SearchIndexIntervalConvention

Field Summary

Fields inherited from class org.apache.commons.math3.utils.AbstractSearchIndex

convention, iMax, iMin, tab

Constructor Summary

RecordSegmentSearchIndex(ISearchIndex searchAlgorithm2)
Constructor of search index class with memorization of the last found index in order to optimize the search and find the index quickly if it belongs to a close neighborhood of the last one (+/- 2 points).

Method Summary

int	getIndex(double x) Returns the index of x in a tab depending on the convention used.
int	getIndex(double x, int min, int max) Returns the index of x in the extracted tab [tab[iMin], tab[iMax]] depending on the convention used.
int	getIndexClosedOpen(double x) Returns the index of x in a tab depending on the convention used.
int	getIndexOpenClosed(double x) Returns the index of x in a tab depending on the convention used.
void	updateStencil() The search algorithm is based on a four-point stencil.

Methods inherited from class org.apache.commons.math3.utils.AbstractSearchIndex

getConvention, getTab

Methods inherited from class java.lang.Object

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

Constructor Detail

RecordSegmentSearchIndex

public RecordSegmentSearchIndex(ISearchIndex searchAlgorithm2)

Constructor of search index class with memorization of the last found index in order to optimize the search and find the index quickly if it belongs to a close neighborhood of the last one (+/- 2 points).

Parameters:

searchAlgorithm2 - : the choice of algorithm is made directly through an instance of a class that implements ISearchIndex

Method Detail

updateStencil

public void updateStencil()

The search algorithm is based on a four-point stencil. To take into account the boundary condition, we have :
- if i = - 1 (point outside domain by lower bound), xi-1 = xi = - inf
- if i = 0 (lower bound), xi-1 = - inf
- if i = nMax - 1, xi+2 = + inf
- if i = nMax, xi+2 = xi+1 = + inf

Since:

2.3.1

getIndexClosedOpen

public int getIndexClosedOpen(double x)

Returns the index of x in a tab depending on the convention used.
Therefore no exception is returned even if x does not belong to [tab[0], tab[numberOfPoints - 1] ]
- if x = tab[i], the integer returned is i - if tab[i] < x < tab[i + 1], the integer returned is i - if x < tab[0], the integer returned is -1 - if x >= tab[numberOfPoints-1], the integer returned is numberOfPoints-1

Parameters:

x - : the value to search.

Returns:

the corresponding index, see the above conditions.

getIndexOpenClosed

public int getIndexOpenClosed(double x)

Returns the index of x in a tab depending on the convention used.
Therefore no exception is returned even if x does not belong to [tab[0], tab[numberOfPoints - 1] ]
- if x = tab[i], the integer returned is i - 1
- if tab[i] < x < tab[i + 1], the integer returned is i
- if x <= tab[0], the integer returned is -1
- if x > tab[numberOfPoints-1], the integer returned is numberOfPoints-1

Parameters:

x - : the value to search.

Returns:

the corresponding index, see the above conditions.

getIndex

public int getIndex(double x)

Returns the index of x in a tab depending on the convention used.
Therefore no exception is returned even if x does not belong to [tab[0], tab[numberOfPoints - 1] ]

Parameters:

x - : the value to search.

Returns:

the corresponding index, see the above conditions.

getIndex

public int getIndex(double x,
                    int min,
                    int max)

Returns the index of x in the extracted tab [tab[iMin], tab[iMax]] depending on the convention used.

Parameters:

x - : the value to search.

min - : defines the lower bound of the tab for the search.

max - : defines the upper bound of the tab for the search.

Returns:

the corresponding index, see the above conditions.