com.github.mikephil.charting.data.filter

Class Approximator

java.lang.Object

com.github.mikephil.charting.data.filter.Approximator

public class Approximator
extends java.lang.Object

Implemented according to Wiki-Pseudocode http://en.wikipedia.org/wiki/Ramer�Douglas�Peucker_algorithm

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Approximator.ApproximatorType enums for the different types of filtering algorithms

Constructor Summary

Constructors

Constructor and Description
Approximator() Initializes the approximator with type NONE
Approximator(Approximator.ApproximatorType type, double tolerance) Initializes the approximator with the given type and tolerance.

Method Summary

Modifier and Type	Method and Description
double	calcAngle(Entry p1, Entry p2) calculates the angle between two Entries (points) in the chart
double	calcAngleBetweenLines(Entry start1, Entry end1, Entry start2, Entry end2) Calculates the angle between two given lines.
double	calcAngleWithRatios(Entry p1, Entry p2) calculates the angle between two Entries (points) in the chart taking ratios into consideration
double	calcPointToLineDistance(Entry startEntry, Entry endEntry, Entry entryPoint) calculate the distance between a line between two entries and an entry (point)
java.util.List<Entry>	filter(java.util.List<Entry> points) Filters according to type.
java.util.List<Entry>	filter(java.util.List<Entry> points, double tolerance) Filters according to type.
void	setRatios(float deltaRatio, float scaleRatio) Sets the ratios for x- and y-axis, as well as the ratio of the scale levels
void	setTolerance(double tolerance) sets the tolerance for the Approximator.
void	setType(Approximator.ApproximatorType type) Sets the filtering algorithm that should be used.
void	setup(Approximator.ApproximatorType type, double tolerance) sets type and tolerance, if tolerance <= 0, no filtering will be done

Methods inherited from class java.lang.Object

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

Constructor Detail

Approximator

public Approximator()

Initializes the approximator with type NONE

Approximator

public Approximator(Approximator.ApproximatorType type,
                    double tolerance)

Initializes the approximator with the given type and tolerance. If toleranec <= 0, no filtering will be done.

Parameters:

type -

Method Detail

setup

public void setup(Approximator.ApproximatorType type,
                  double tolerance)

sets type and tolerance, if tolerance <= 0, no filtering will be done

Parameters:

type -

tolerance -

setTolerance

public void setTolerance(double tolerance)

sets the tolerance for the Approximator. When using the Douglas-Peucker-Algorithm, the tolerance is an angle in degrees, that will trigger the filtering.

setType

public void setType(Approximator.ApproximatorType type)

Sets the filtering algorithm that should be used.

Parameters:

type -

setRatios

public void setRatios(float deltaRatio,
                      float scaleRatio)

Sets the ratios for x- and y-axis, as well as the ratio of the scale levels

Parameters:

deltaRatio -

scaleRatio -

filter

public java.util.List<Entry> filter(java.util.List<Entry> points)

Filters according to type. Uses the pre set set tolerance

Parameters:

points - the points to filter

Returns:

filter

public java.util.List<Entry> filter(java.util.List<Entry> points,
                                    double tolerance)

Filters according to type.

Parameters:

points - the points to filter

tolerance - the angle in degrees that will trigger the filtering

Returns:

calcPointToLineDistance

public double calcPointToLineDistance(Entry startEntry,
                                      Entry endEntry,
                                      Entry entryPoint)

calculate the distance between a line between two entries and an entry (point)

Parameters:

startEntry - line startpoint

endEntry - line endpoint

entryPoint - the point to which the distance is measured from the line

Returns:

calcAngleBetweenLines

public double calcAngleBetweenLines(Entry start1,
                                    Entry end1,
                                    Entry start2,
                                    Entry end2)

Calculates the angle between two given lines. The provided Entry objects mark the starting and end points of the lines.

Parameters:

start1 -

end1 -

start2 -

end2 -

Returns:

calcAngleWithRatios

public double calcAngleWithRatios(Entry p1,
                                  Entry p2)

calculates the angle between two Entries (points) in the chart taking ratios into consideration

Parameters:

p1 -

p2 -

Returns:

calcAngle

public double calcAngle(Entry p1,
                        Entry p2)

calculates the angle between two Entries (points) in the chart

Parameters:

p1 -

p2 -

Returns: