com.androidplot.xy

Class SampledXYSeries

java.lang.Object

com.androidplot.xy.SampledXYSeries

All Implemented Interfaces:

Series, FastXYSeries, OrderedXYSeries, XYSeries

public class SampledXYSeries
extends java.lang.Object
implements FastXYSeries, OrderedXYSeries

An implementation of FastXYSeries that samples its self into multiple levels to achieve faster rendering / zoom behavior. By default, uses LTTBSampler as it's sampling algorithm. Note that this algorithm does not yet support null values. Sampling behavior is controlled by two values: Ratio: A value greater than 1; controls the sampling ratio of each successive series. For example, a step of 2 would mean that each successive series contains 2x fewer points than the previous. Threshold: A value < the original series size; controls the lower limit at which point sampling should stop. For example, sampling a series with size 1000 given a ratio of 2 and a threshold of 100, three sampled resolutions will be generated: 500 - 2x sampling 250 - 4x sampling 125 - 8x sampling

Nested Class Summary

Nested classes/interfaces inherited from interface com.androidplot.xy.OrderedXYSeries

OrderedXYSeries.XOrder

Constructor Summary

Constructors

Constructor and Description
SampledXYSeries(XYSeries rawData, float ratio, int threshold) Generate a SampledXYSeries from the input series.
SampledXYSeries(XYSeries rawData, OrderedXYSeries.XOrder xOrder, float ratio, int threshold)

Method Summary

Modifier and Type	Method and Description
Sampler	getAlgorithm()
RectRegion	getBounds()
double	getMaxZoomFactor()
float	getRatio()
int	getThreshold()
java.lang.String	getTitle()
java.lang.Number	getX(int index) Returns the x-value for an index within a series.
OrderedXYSeries.XOrder	getXOrder() The order of XVals as they appear in this series.
java.lang.Number	getY(int index) Returns the y-value for an index within a series.
protected static int	getZoomIndex(double zoomFactor, double ratio)
protected java.util.List<EditableXYSeries>	getZoomLevels()
RectRegion	minMax() TIP: You can use RectRegion.union(Number, Number) during to keep a running tally of min/max values when iterating.
void	resample()
void	setAlgorithm(Sampler algorithm)
void	setBounds(RectRegion bounds)
void	setRatio(float ratio)
void	setThreshold(int threshold)
void	setZoomFactor(double factor) Set zoom factor; 2.5 = 2.5x zoom, 10.0 = 10x zoom etc.
int	size()

Methods inherited from class java.lang.Object

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

Constructor Detail

SampledXYSeries

public SampledXYSeries(XYSeries rawData,
                       OrderedXYSeries.XOrder xOrder,
                       float ratio,
                       int threshold)

Parameters:

rawData -

xOrder - If your data is in ascending or descending order, specifying it here speed up optimize render times.

ratio - The ratio used to determine the size of each new sampled series. Must be > 1. downsampled series until threshold is reached.

threshold - The desired size of the smallest sample series. Must be < rawData.size.

SampledXYSeries

public SampledXYSeries(XYSeries rawData,
                       float ratio,
                       int threshold)

Generate a SampledXYSeries from the input series.

Parameters:

rawData - The original series to be downsampled

ratio - The ratio used to determine the size of each new sampled series. Must be > 1. downsampled series until threshold is reached.

threshold - The desired size of the smallest sample series. Must be < rawData.size.

Method Detail

resample

public void resample()

getZoomLevels

protected java.util.List<EditableXYSeries> getZoomLevels()

setZoomFactor

public void setZoomFactor(double factor)

Set zoom factor; 2.5 = 2.5x zoom, 10.0 = 10x zoom etc. This method will set the zoom level to the closest available factor to the specified factor; a specified factor of 4.5x may result in an actual factor of 4x.

Parameters:

factor -

getZoomIndex

protected static int getZoomIndex(double zoomFactor,
                                  double ratio)

getMaxZoomFactor

public double getMaxZoomFactor()

getAlgorithm

public Sampler getAlgorithm()

setAlgorithm

public void setAlgorithm(Sampler algorithm)

getTitle

public java.lang.String getTitle()

Specified by:

getTitle in interface Series

Returns:

The title of this Series.

size

public int size()

Specified by:

size in interface XYSeries

Returns:

Number of elements in this Series.

getX

public java.lang.Number getX(int index)

Description copied from interface: XYSeries

Returns the x-value for an index within a series.

Specified by:

getX in interface XYSeries

Parameters:

index - the index index (in the range 0 to size()-1).

Returns:

The x-value.

getY

public java.lang.Number getY(int index)

Description copied from interface: XYSeries

Returns the y-value for an index within a series.

Specified by:

getY in interface XYSeries

Parameters:

index - the index index (in the range 0 to size()-1).

Returns:

The y-value.

getThreshold

public int getThreshold()

setThreshold

public void setThreshold(int threshold)

getBounds

public RectRegion getBounds()

setBounds

public void setBounds(RectRegion bounds)

minMax

public RectRegion minMax()

Description copied from interface: FastXYSeries

TIP: You can use RectRegion.union(Number, Number) during to keep a running tally of min/max values when iterating.

Specified by:

minMax in interface FastXYSeries

Returns:

A RectRegion representing the min/max values that currently exist this series.

getXOrder

public OrderedXYSeries.XOrder getXOrder()

Description copied from interface: OrderedXYSeries

The order of XVals as they appear in this series.

Specified by:

getXOrder in interface OrderedXYSeries

Returns:

getRatio

public float getRatio()

setRatio

public void setRatio(float ratio)