## org.das2.qds.math.fft.GeneralFFT

Provides forward and reverse FFT methods for any number of elements. The FFTs are implemented using a modified version of the jnt.FFT package from NIST. This version operates on ComplexArray objects that may be backed by das2 data sets avoiding unnecessary copies.

## GeneralFFT( int n, boolean doublePrecision, boolean real )

Initialize the FFT object by constructing wave tables that can be repeatly used.

## invTransform

invTransform( org.das2.qds.math.fft.ComplexArray.Double data ) → void

perform the inverse transform on the array in situ.

### Parameters

data - a ComplexArray.Double

### Returns:

void (returns nothing)
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## invTransform

invTransform( org.das2.qds.math.fft.ComplexArray.Float data ) → void

perform the inverse transform on the array in situ.

### Parameters

data - a ComplexArray.Float

### Returns:

void (returns nothing)
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## newDoubleFFT

newDoubleFFT( int n ) → org.das2.qds.math.fft.GeneralFFT

creates an FFT object that operates on a ComplexArray.Double of n elements.

### Parameters

n - an int

### Returns:

org.das2.qds.math.fft.GeneralFFT
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## newFloatFFT

newFloatFFT( int n ) → org.das2.qds.math.fft.GeneralFFT

creates an FFT object that operates on a ComplexArray.Float of n elements.

### Parameters

n - an int

### Returns:

org.das2.qds.math.fft.GeneralFFT
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## size

size( ) → int

return the number of points in the fft.

### Returns:

the number of points in the fft.
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## transform

transform( org.das2.qds.math.fft.ComplexArray.Double data ) → void

perform the forward transform on the array in situ.

### Parameters

data - a ComplexArray.Double

### Returns:

void (returns nothing)
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## transform

transform( org.das2.qds.math.fft.ComplexArray.Float data ) → void

perform the forward transform on the array in situ.

### Parameters

data - a ComplexArray.Float

### Returns:

void (returns nothing)
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