## jnt.FFT Class ComplexFloat2DFFT

```java.lang.Object
|
+--jnt.FFT.ComplexFloat2DFFT
```

public class ComplexFloat2DFFT
extends java.lang.Object

Computes the FFT of 2 dimensional complex, single precision data. The data is stored in a 1-dimensional array in Row-Major order. The physical layout in the array data, of the mathematical data d[i,j] is as follows:

```    Re(d[i,j]) = data[i*rowspan + 2*j]
Im(d[i,j]) = data[i*rowspan + 2*j + 1]
```
where `rowspan` must be at least 2*ncols (it defaults to 2*ncols). The transformed data is returned in the original data array in wrap-around order along each dimension.

 Constructor Summary ```ComplexFloat2DFFT(int nrows, int ncols)```           Create an FFT for transforming nrows*ncols points of Complex, double precision data.

 Method Summary ` void` `backtransform(float[] data)`           Compute the (unnomalized) inverse FFT of data, leaving it in place. ` void` ```backtransform(float[] data, int rowspan)```           Compute the (unnomalized) inverse FFT of data, leaving it in place. `protected  void` ```checkData(float[] data, int rowspan)``` ` void` `inverse(float[] data)`           Compute the (nomalized) inverse FFT of data, leaving it in place. ` void` ```inverse(float[] data, int rowspan)```           Compute the (nomalized) inverse FFT of data, leaving it in place. ` float` `normalization()`           Return the normalization factor. ` float[]` `toWraparoundOrder(float[] data)`           Return data in wraparound order. ` float[]` ```toWraparoundOrder(float[] data, int rowspan)```           Return data in wraparound order. ` void` `transform(float[] data)`           Compute the Fast Fourier Transform of data leaving the result in data. ` void` ```transform(float[] data, int rowspan)```           Compute the Fast Fourier Transform of data leaving the result in data.

 Methods inherited from class java.lang.Object ```clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait```

 Constructor Detail

### ComplexFloat2DFFT

```public ComplexFloat2DFFT(int nrows,
int ncols)```
Create an FFT for transforming nrows*ncols points of Complex, double precision data.
 Method Detail

### checkData

```protected void checkData(float[] data,
int rowspan)```

### transform

`public void transform(float[] data)`
Compute the Fast Fourier Transform of data leaving the result in data. The array data must be dimensioned (at least) 2*nrows*ncols, consisting of alternating real and imaginary parts.

### transform

```public void transform(float[] data,
int rowspan)```
Compute the Fast Fourier Transform of data leaving the result in data. The array data must be dimensioned (at least) 2*nrows*ncols, consisting of alternating real and imaginary parts.

### toWraparoundOrder

`public float[] toWraparoundOrder(float[] data)`
Return data in wraparound order.
wraparound format

### toWraparoundOrder

```public float[] toWraparoundOrder(float[] data,
int rowspan)```
Return data in wraparound order. rowspan is used to traverse data; the new array is in packed (rowspan = 2*ncols) format.
wraparound format

### backtransform

`public void backtransform(float[] data)`
Compute the (unnomalized) inverse FFT of data, leaving it in place.

### backtransform

```public void backtransform(float[] data,
int rowspan)```
Compute the (unnomalized) inverse FFT of data, leaving it in place.

### normalization

`public float normalization()`
Return the normalization factor. Multiply the elements of the backtransform'ed data to get the normalized inverse.

### inverse

`public void inverse(float[] data)`
Compute the (nomalized) inverse FFT of data, leaving it in place.

### inverse

```public void inverse(float[] data,
int rowspan)```
Compute the (nomalized) inverse FFT of data, leaving it in place.