edu.wisc.ssec.mcidasv.adt

Class FFT

java.lang.Object

edu.wisc.ssec.mcidasv.adt.FFT

public class FFT
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
private static int	FFTBINS
private static double[]	fftComplex
private static double[]	fftMagnitude
private static double[]	fftReal

Constructor Summary

Constructors

Modifier	Constructor and Description
private	FFT()

Method Summary

Modifier and Type	Method and Description
static int	calculateFFT(double[] inputArray)
private static double	complexAbs(double realValue, double imaginaryValue)
private static int	dfft() A Duhamel-Hollman split-radix dif FFT.

Methods inherited from class java.lang.Object

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

Field Detail

FFTBINS

private static int FFTBINS

fftReal

private static double[] fftReal

fftComplex

private static double[] fftComplex

fftMagnitude

private static double[] fftMagnitude

Constructor Detail

FFT

private FFT()

Method Detail

dfft

private static int dfft()

A Duhamel-Hollman split-radix dif FFT. Ref: Electronics Letters, Jan. 5, 1984 Complex input and output data in arrays x and y Length is n. Inputs : RealArray_Input - Input data array to perform FFT analysis CmplxArray_Input - Empty on input NumBins - Number of histogram bins in input array Outputs : RealArray_Input - Real part of FFT Analysis CmplxArray_Input - Complex part of FFT Analysis

Returns:

Values <= 0 are errors, while anything > 0 is ok.

complexAbs

private static double complexAbs(double realValue,
                                 double imaginaryValue)

calculateFFT

public static int calculateFFT(double[] inputArray)