de.gsi.chart.renderer.datareduction

Class DefaultDataReducer

java.lang.Object

de.gsi.chart.renderer.datareduction.DefaultDataReducer

All Implemented Interfaces:

RendererDataReducer

public class DefaultDataReducer
extends Object
implements RendererDataReducer

Default data reduction algorithm implementation for the ErrorDataSet Renderer
Simple algorithm that reduces the number of points if neighbouring x coordinates are closer than the user-defined dash size. Points in between are dropped and their errors propagated to the following drawn data point. N.B. numerical complexity: average = worst-case = O(n)

Author:

rstein

Property Summary

Type	Property and Description
IntegerProperty	minPointPixelDistance

Field Summary

Fields

Modifier and Type	Field and Description
protected IntegerProperty	minPointPixelDistance

Constructor Summary

Constructors

Constructor and Description
DefaultDataReducer()

Method Summary

Modifier and Type	Method and Description
int	getMinPointPixelDistance()
IntegerProperty	minPointPixelDistanceProperty()
int	reducePoints(double[] xValues, double[] yValues, double[] xPointErrorsPos, double[] xPointErrorsNeg, double[] yPointErrorsPos, double[] yPointErrorsNeg, String[] styles, boolean[] pointSelected, int indexMin, int indexMax) Internal function to the ErrorDataSetRenderer arrays are cached copies and operations are assumed to be performed in-place (<-> for performance reasons/minimisation of memory allocation)
void	setMinPointPixelDistance(int minPixelDistance) Sets the minPointPixelDistance to the specified value.

Methods inherited from class java.lang.Object

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

Property Detail

minPointPixelDistance

public final IntegerProperty minPointPixelDistanceProperty

See Also:

getMinPointPixelDistance(), setMinPointPixelDistance(int)

Field Detail

minPointPixelDistance

protected IntegerProperty minPointPixelDistance

Constructor Detail

DefaultDataReducer

public DefaultDataReducer()

Method Detail

getMinPointPixelDistance

public final int getMinPointPixelDistance()

Returns:

the minPointPixelDistance.

minPointPixelDistanceProperty

public final IntegerProperty minPointPixelDistanceProperty()

See Also:

getMinPointPixelDistance(), setMinPointPixelDistance(int)

reducePoints

public int reducePoints(double[] xValues,
                        double[] yValues,
                        double[] xPointErrorsPos,
                        double[] xPointErrorsNeg,
                        double[] yPointErrorsPos,
                        double[] yPointErrorsNeg,
                        String[] styles,
                        boolean[] pointSelected,
                        int indexMin,
                        int indexMax)

Internal function to the ErrorDataSetRenderer arrays are cached copies and operations are assumed to be performed in-place (<-> for performance reasons/minimisation of memory allocation)

Specified by:

reducePoints in interface RendererDataReducer

Parameters:

xValues - array of x coordinates

yValues - array of y coordinates

xPointErrorsPos - array of coordinates containing x+exp

xPointErrorsNeg - array of coordinates containing x-exn

yPointErrorsPos - array of coordinates containing x+eyp

yPointErrorsNeg - array of coordinates containing x+eyn

pointSelected - array containing the points that have been specially selected by the user

indexMin - minimum index of those array that shall be considered

indexMax - maximum index of those array that shall be considered

styles - point styles

Returns:

effective number of points that remain after the reduction

setMinPointPixelDistance

public final void setMinPointPixelDistance(int minPixelDistance)

Sets the minPointPixelDistance to the specified value.

Parameters:

minPixelDistance - the minimum distance between two adjacent points.