de.gsi.math.spectra.dht

Class DoubleDHT_2D

java.lang.Object

de.gsi.math.spectra.dht.DoubleDHT_2D

public class DoubleDHT_2D
extends Object

Computes 2D Discrete Hartley Transform (DHT) of real, double precision data. The sizes of both dimensions can be arbitrary numbers. This is a parallel implementation optimized for SMP systems.

Part of code is derived from General Purpose FFT Package written by Takuya Ooura (http://www.kurims.kyoto-u.ac.jp/~ooura/fft.html)

Author:

Piotr Wendykier (piotr.wendykier@gmail.com)

Constructor Summary

Constructors

Constructor and Description
DoubleDHT_2D(int rows, int column) Creates new instance of DoubleDHT_2D.

Method Summary

Modifier and Type	Method and Description
void	forward(double[] a) Computes 2D real, forward DHT leaving the result in a.
void	forward(double[][] a) Computes 2D real, forward DHT leaving the result in a.
void	inverse(double[][] a, boolean scale) Computes 2D real, inverse DHT leaving the result in a.
void	inverse(double[] a, boolean scale) Computes 2D real, inverse DHT leaving the result in a.

Methods inherited from class java.lang.Object

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

Constructor Detail

DoubleDHT_2D

public DoubleDHT_2D(int rows,
                    int column)

Creates new instance of DoubleDHT_2D.

Parameters:

rows - number of rows

column - number of columns

Method Detail

forward

public void forward(double[] a)

Computes 2D real, forward DHT leaving the result in a. The data is stored in 1D array in row-major order.

Parameters:

a - data to transform

forward

public void forward(double[][] a)

Computes 2D real, forward DHT leaving the result in a. The data is stored in 2D array.

Parameters:

a - data to transform

inverse

public void inverse(double[] a,
                    boolean scale)

Computes 2D real, inverse DHT leaving the result in a. The data is stored in 1D array in row-major order.

Parameters:

a - data to transform

scale - if true then scaling is performed

inverse

public void inverse(double[][] a,
                    boolean scale)

Computes 2D real, inverse DHT leaving the result in a. The data is stored in 2D array.

Parameters:

a - data to transform

scale - if true then scaling is performed