## org.das2.qds.math.fft.FFTUtil

## FFTUtil( )

## fft

fft( org.das2.qds.math.fft.GeneralFFT fft, QDataSet vds, Units units ) → org.das2.qds.math.fft.ComplexArray.Double

do not use this--it should not be public!

### Parameters

fft - a GeneralFFT
vds - a QDataSet
units - an Units

### Returns:

an org.das2.qds.math.fft.ComplexArray.Double
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## fftPower

fftPower( org.das2.qds.math.fft.GeneralFFT fft, QDataSet vds ) → QDataSet

### Parameters

fft - a GeneralFFT
vds - a QDataSet

### Returns:

org.das2.qds.QDataSet
[search for examples] [view on GitHub] [view on old javadoc] [view source]

## fftPower

fftPower( org.das2.qds.math.fft.GeneralFFT fft, QDataSet vds, QDataSet weights ) → QDataSet

Produces the power spectrum of the dataset. This is the length of the fourier components squared, normalized by the bandwidth. The result dataset has dimensionless yunits.

### Parameters

fft - a GeneralFFT
vds - VectorDataSet with x units TimeLocationUnits.
weights - a QDataSet

### Returns:

org.das2.qds.QDataSet
[search for examples] [view on GitHub] [view on old javadoc] [view source]

## getFrequencyDomainTags

getFrequencyDomainTags( double fs, int size ) → double[]

### Parameters

fs - the sampling frequency
size - an int

### Returns:

the frequencies of the bins
[search for examples] [view on GitHub] [view on old javadoc] [view source]

## getWindow10PercentEdgeCosine

getWindow10PercentEdgeCosine( int size ) → QDataSet

### Parameters

size - an int

### Returns:

org.das2.qds.QDataSet
[search for examples] [view on GitHub] [view on old javadoc] [view source]

## getWindowUnity

getWindowUnity( int size ) → QDataSet

### Parameters

size - an int

### Returns:

org.das2.qds.QDataSet
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