edu.udo.cs.yale.tools.math
Class WindowFunction

java.lang.Object
  edu.udo.cs.yale.tools.math.WindowFunction

public class WindowFunction
extends java.lang.Object

Window functions apply a weight to each value of a value series depending on the length of the series. Window Functions like Hanning windows are usually applied before a Fourier transformation.

Version:

$Id: WindowFunction.java,v 1.10 2006/08/03 14:39:34 ingomierswa Exp $

Author:

Ingo Mierswa

Field Summary

static int	BARTLETT The constant for the function Bartlett.
static int	BLACKMAN The constant for the function Blackman.
static int	BLACKMAN_HARRIS The constant for the function Blackman-Harris.
static java.lang.String[]	FUNCTIONS The currently implemented window functions.
static int	HAMMING The constant for the function Hamming.
static int	HANNING The constant for the function Hanning.
private int	length
static int	NONE The constant for the function Hanning.
static int	RECTANGLE The constant for the function Rectangle.
private int	type

Constructor Summary

WindowFunction(int type, int maxIndex)

Method Summary

double

getFactor(int n) Returns the weighting factor for the current value n in a window of the given length.

Methods inherited from class java.lang.Object

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

Field Detail

FUNCTIONS

public static final java.lang.String[] FUNCTIONS

The currently implemented window functions.

NONE

public static final int NONE

The constant for the function Hanning.

See Also:

Constant Field Values

HANNING

public static final int HANNING

The constant for the function Hanning.

See Also:

Constant Field Values

HAMMING

public static final int HAMMING

The constant for the function Hamming.

See Also:

Constant Field Values

BLACKMAN

public static final int BLACKMAN

The constant for the function Blackman.

See Also:

Constant Field Values

BLACKMAN_HARRIS

public static final int BLACKMAN_HARRIS

The constant for the function Blackman-Harris.

See Also:

Constant Field Values

BARTLETT

public static final int BARTLETT

The constant for the function Bartlett.

See Also:

Constant Field Values

RECTANGLE

public static final int RECTANGLE

The constant for the function Rectangle.

See Also:

Constant Field Values

type

private int type

length

private int length

Constructor Detail

WindowFunction

public WindowFunction(int type,
                      int maxIndex)

Method Detail

getFactor

public double getFactor(int n)

Returns the weighting factor for the current value n in a window of the given length. The calculation of this factor is done in dependance of the function type.