edu.stanford.math.plex4.homology.filtration

Class IncreasingLinearConverter

java.lang.Object

edu.stanford.math.plex4.homology.filtration.FiltrationConverter

edu.stanford.math.plex4.homology.filtration.IncreasingLinearConverter

All Implemented Interfaces:

edu.stanford.math.primitivelib.autogen.functional.ObjectObjectFunction<Interval<java.lang.Integer>,Interval<java.lang.Double>>

public class IncreasingLinearConverter
extends FiltrationConverter

This class implements a conversion between filtration values and filtration indices that is linear and increasing. If we let f_k be the filtration value at index k and N is the number of divisions, then this mapping satisfies:

• f_k = min + k * delta
• f_0 = min
• f_{N-1} = max

Author:

Andrew Tausz

Constructor Summary

Constructors

Constructor and Description
IncreasingLinearConverter(int numDivisions, double maxFiltrationValue) This initializes the object with a default minimum filtration value of zero.
IncreasingLinearConverter(int numDivisions, double minFiltrationValue, double maxFiltrationValue) This constructor initializes the object with the number of divisions in the range, and the minimum and maximum values.

Method Summary

Methods

Modifier and Type	Method and Description
double	computeInducedFiltrationValue(double filtrationValue1, double filtrationValue2) This function computes the filtration value that is consistent with the ordering of filtration indices.
double	getDelta()
int	getFiltrationIndex(double filtrationValue) This function computes the index based on a filtration value.
double	getFiltrationValue(int filtrationIndex) This function computes the filtration value from a filtration index.
double	getInitialFiltrationValue() This function returns the filtration at index 0.
double	getMaxFiltrationValue()
double	getMinFiltrationValue()
int	getNumDivisions()

Methods inherited from class edu.stanford.math.plex4.homology.filtration.FiltrationConverter

evaluate, transform

Methods inherited from class java.lang.Object

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

Constructor Detail

IncreasingLinearConverter

public IncreasingLinearConverter(int numDivisions,
                         double minFiltrationValue,
                         double maxFiltrationValue)

This constructor initializes the object with the number of divisions in the range, and the minimum and maximum values.

Parameters:

numDivisions - the number of divisions to use in the range

minFiltrationValue - the minimum filtration value

maxFiltrationValue - the maximum filtration value

IncreasingLinearConverter

public IncreasingLinearConverter(int numDivisions,
                         double maxFiltrationValue)

This initializes the object with a default minimum filtration value of zero.

Parameters:

numDivisions - the number of divisions in the range

maxFiltrationValue - the maximum filtration value

Method Detail

getFiltrationIndex

public int getFiltrationIndex(double filtrationValue)

Description copied from class: FiltrationConverter

This function computes the index based on a filtration value.

Specified by:

getFiltrationIndex in class FiltrationConverter

Parameters:

filtrationValue - the value to convert

Returns:

the filtration index of the given value

getFiltrationValue

public double getFiltrationValue(int filtrationIndex)

Description copied from class: FiltrationConverter

This function computes the filtration value from a filtration index.

Specified by:

getFiltrationValue in class FiltrationConverter

Parameters:

filtrationIndex - the index to convert

Returns:

the filtration value for the particular index

computeInducedFiltrationValue

public double computeInducedFiltrationValue(double filtrationValue1,
                                   double filtrationValue2)

Description copied from class: FiltrationConverter

This function computes the filtration value that is consistent with the ordering of filtration indices. For example, for filtration values that are increasing with filtration indices, this should be the max function.

Specified by:

computeInducedFiltrationValue in class FiltrationConverter

Returns:

the filtration value that is induced by two filtration values

getInitialFiltrationValue

public double getInitialFiltrationValue()

Description copied from class: FiltrationConverter

This function returns the filtration at index 0.

Specified by:

getInitialFiltrationValue in class FiltrationConverter

Returns:

the filtration at index 0

getNumDivisions

public int getNumDivisions()

Returns:

the number of divisions

getMinFiltrationValue

public double getMinFiltrationValue()

Returns:

the minimum filtration value

getMaxFiltrationValue

public double getMaxFiltrationValue()

Returns:

the maximum filtration value

getDelta

public double getDelta()

Returns:

the spacing between the points