de.labAlive.measure.spectrum.dft

Class Fft

java.lang.Object

de.labAlive.measure.spectrum.dft.FourierTransformationAlgorithm

de.labAlive.measure.spectrum.dft.Fft

public class Fft
extends FourierTransformationAlgorithm

Constructor Summary

Constructors

Constructor and Description
Fft()

Method Summary

Modifier and Type	Method and Description
int	getNextValidNumberofSamples(int proposedNumberofSamples) FFT size (must be 2^n), i.e. the number of samples to be transformed.
double[]	transform(Signal[] signal) FFT implementation - calculation of the spectrum.

Methods inherited from class de.labAlive.measure.spectrum.dft.FourierTransformationAlgorithm

getMaxNumberofSamples

Methods inherited from class java.lang.Object

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

Constructor Detail

Fft

public Fft()

Method Detail

transform

public double[] transform(Signal[] signal)

FFT implementation - calculation of the spectrum. (Factor 1/N, N is size, is not considered.)

Specified by:

transform in class FourierTransformationAlgorithm

Parameters:

signal - size must be 2^n

Returns:

spectrum

getNextValidNumberofSamples

public int getNextValidNumberofSamples(int proposedNumberofSamples)

FFT size (must be 2^n), i.e. the number of samples to be transformed. Valid number of samples is calculated.

Specified by:

getNextValidNumberofSamples in class FourierTransformationAlgorithm

Returns:

Number of samples that are transformed must be 2^n. Number of samples >= proposedNumberofSamples