org.apache.commons.math3.transform
Class FastFourierTransformer

java.lang.Object
  org.apache.commons.math3.transform.AbstractFastFourierTransformer
      org.apache.commons.math3.transform.FastFourierTransformer

All Implemented Interfaces:

IFastFourierTransformer

public class FastFourierTransformer
extends AbstractFastFourierTransformer

This class allows the computation of a Fast Fourier Transform for all kind (odd or powers of two) orders.

Since:

2.3

Version:

$Id: FastFourierTransformer.java 10741 2014-09-11 08:52:22Z laurens $

Constructor Summary

FastFourierTransformer(DftNormalization dftNormalization)
Constructor of the class FastFourierTransformer, inherited from the one of the abstract class AbstractFastFourierTransformer

Method Summary

Object	mdfft(Object mdca, TransformType type) Deprecated. see MATH-736
Complex[]	transform(Complex[] f, TransformType type) Returns the (forward, inverse) transform of the specified complex data set.
Complex[]	transform(double[] f, TransformType type) Returns the (forward, inverse) transform of the specified real data set.

Methods inherited from class org.apache.commons.math3.transform.AbstractFastFourierTransformer

getNormalization, normalizeTransformedData, transform

Methods inherited from class java.lang.Object

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

Constructor Detail

FastFourierTransformer

public FastFourierTransformer(DftNormalization dftNormalization)

Constructor of the class FastFourierTransformer, inherited from the one of the abstract class AbstractFastFourierTransformer

Parameters:

dftNormalization - an enum with two possible values : STANDARD or UNITARY

Method Detail

transform

public Complex[] transform(double[] f,
                           TransformType type)

Returns the (forward, inverse) transform of the specified real data set.

Parameters:

f - the real data array to be transformed

type - the type of transform (forward, inverse) to be performed

Returns:

the complex transformed array

transform

public Complex[] transform(Complex[] f,
                           TransformType type)

Returns the (forward, inverse) transform of the specified complex data set.

Parameters:

f - the complex data array to be transformed

type - the type of transform (forward, inverse) to be performed

Returns:

the complex transformed array

mdfft

@Deprecated
public Object mdfft(Object mdca,
                               TransformType type)

Deprecated. see MATH-736

Performs a multi-dimensional Fourier transform on a given array. Use transform(Complex[], TransformType) in a row-column implementation in any number of dimensions with O(N×log(N)) complexity with N = n₁ × n₂ ×n₃ × ... × n_d, where n_k is the number of elements in dimension k, and d is the total number of dimensions.

Parameters:

mdca - Multi-Dimensional Complex Array, i.e. Complex[][][][]

type - the type of transform (forward, inverse) to be performed

Returns:

transform of mdca as a Multi-Dimensional Complex Array, i.e. Complex[][][][]

Throws:

IllegalArgumentException - if any dimension is not a power of two