java.lang.Object
- java.lang.Thread
- - gov.nih.mipav.model.algorithms.AlgorithmBase
  - - gov.nih.mipav.model.algorithms.filters.ChirpZTransform

All Implemented Interfaces:

java.awt.event.ActionListener, java.awt.event.WindowListener, java.lang.Runnable, java.util.EventListener
```
public class ChirpZTransform
extends AlgorithmBase
```
Author:

ilb This is a port of code in the file czt.py by John Garrett. MIT License Copyright (c) 2020 John Garrett Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. The chirp Z-transform (CZT) is a generalization of the discrete Fourier transform (DFT). While the DFT samples the Z plane at uniformly-spaced points along the unit circle, the chirp Z-transform samples along spiral arcs in the Z-plane, corresponding to straight lines in the S plane. The DFT, real DFT, and zoom DFT can be calculated as special cases of the CZT. References ---------- - [L. Rabiner, R. Schafer and C. Rader, "The chirp z-transform algorithm, "*IEEE Transactions on Audio and Electroacoustics*, vol. 17, no. 2, pp. 86-92, Jun. 1969, doi: 10.1109/TAU.1969.1162034.](https://web.ece.ucsb.edu/Faculty/Rabiner/ece259/Reprints/015_czt.pdf) - [V. Sukhoy and A. Stoytchev, "Generalizing the inverse FFT off the unit circle," *Scientific Reports*, vol. 9, no. 14443, Oct. 2019, doi: 10.1038/s41598-019-50234-9.](https://doi.org/10.1038/s41598-019-50234-9) - [Chirp Z-Transform (Wikipedia)](https://en.wikipedia.org/wiki/Chirp_Z-transform) - [Discrete Fourier Transform (Wikipedia)](https://en.wikipedia.org/wiki/Discrete_Fourier_transform)

Nested Class Summary
- Nested classes/interfaces inherited from class java.lang.Thread
  java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields
Modifier and Type	Field	Description
`private double[]`	`A`
`private java.lang.String`	`f_method`
`private boolean`	`forward`
`private int`	`M`
`private int`	`MN`
`private int`	`N`
`private double[][]`	`output`
`private boolean`	`simple`
`private java.lang.String`	`t_method`
`private ViewUserInterface`	`UI`
`private double[]`	`W`
`private double[][]`	`x`
`private double[][]`	`X`
`private double[][]`	`xX`

Fields inherited from class gov.nih.mipav.model.algorithms.AlgorithmBase
destFlag, destImage, image25D, mask, maxProgressValue, minProgressValue, multiThreadingEnabled, nthreads, progress, progressModulus, progressStep, runningInSeparateThread, separable, srcImage, threadStopped

Fields inherited from class java.lang.Thread
MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors
Constructor	Description
`ChirpZTransform()`
`ChirpZTransform(double[][] output, double[][] xX, int MN, double[] W, double[] A, boolean simple, java.lang.String t_method, java.lang.String f_method, boolean forward)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`private double[][]`	`_circulant_multiply(double[][] corg, double[][] xorg, java.lang.String f_method)`
`private void`	`_czt(double[][] output, double[][] x, int M, double[] W, double[] A)`
`private double[][]`	`_fft(double[][] x)`
`private double[][]`	`_ifft(double[][] y)`
`private double[]`	`_signal_model(double[] tt)`
`private double[][]`	`_skew_circulant_multiply(double[][] c, double[][] x, java.lang.String f_method)`
`private double[][]`	`_toeplitz_mult_ce(double[][] r, double[][] c, double[][] x, java.lang.String f_method)`
`private double[][]`	`_toeplitz_mult_pd(double[][] r, double[][] c, double[][] x, java.lang.String f_method)`
`private void`	`assert_almost_equal(double[][] actual, double[][] desired, int decimal, java.lang.String actualString, java.lang.String desiredString)`
`private double`	`log2(double input)`
`void`	`runAlgorithm()`	Actually runs the algorithm.
`void`	`test_compare_different_czt_methods()`	Starts the program.
`private double[][][]`	`toeplitz(double[][] c, double[][] r)`
`private double`	`zabs(double zr, double zi)`	zabs computes the absolute value or magnitude of a double precision complex variable zr + j*zi.
`private void`	`zdiv(double ar, double ai, double br, double bi, double[] cr, double[] ci)`	complex divide c = a/b.
`private void`	`zexp(double ar, double ai, double[] br, double[] bi)`	complex exponential function b = exp(a).
`private void`	`zlog(double ar, double ai, double[] br, double[] bi, int[] ierr)`	complex logarithm b = clog(a).
`private void`	`zmlt(double ar, double ai, double br, double bi, double[] cr, double[] ci)`	complex multiply c = a * b.
`private void`	`zpow(double zr, double zi, double a, double[] br, double[] bi, int[] ierr)`	b = z*a = exp(alog(z))

Methods inherited from class gov.nih.mipav.model.algorithms.AlgorithmBase
actionPerformed, addListener, addProgressChangeListener, calculateImageSize, calculatePrincipleAxis, computeElapsedTime, computeElapsedTime, convertIntoFloat, delinkProgressToAlgorithm, delinkProgressToAlgorithmMulti, displayError, errorCleanUp, finalize, fireProgressStateChanged, fireProgressStateChanged, fireProgressStateChanged, fireProgressStateChanged, fireProgressStateChanged, generateProgressValues, getDestImage, getElapsedTime, getMask, getMaxProgressValue, getMinProgressValue, getNumberOfThreads, getProgress, getProgressChangeListener, getProgressChangeListeners, getProgressModulus, getProgressStep, getProgressValues, getSrcImage, isCompleted, isImage25D, isMultiThreadingEnabled, isRunningInSeparateThread, isThreadStopped, linkProgressToAlgorithm, linkProgressToAlgorithm, makeProgress, notifyListeners, removeListener, removeProgressChangeListener, run, setCompleted, setImage25D, setMask, setMaxProgressValue, setMinProgressValue, setMultiThreadingEnabled, setNumberOfThreads, setProgress, setProgressModulus, setProgressStep, setProgressValues, setProgressValues, setRunningInSeparateThread, setSrcImage, setStartTime, setThreadStopped, startMethod, windowActivated, windowClosed, windowClosing, windowDeactivated, windowDeiconified, windowIconified, windowOpened

Methods inherited from class java.lang.Thread
activeCount, checkAccess, clone, countStackFrames, currentThread, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, onSpinWait, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, suspend, toString, yield

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

UI
```
private ViewUserInterface UI
```

xX
```
private double[][] xX
```

x
```
private double[][] x
```

X
```
private double[][] X
```

MN
```
private int MN
```

M
```
private int M
```

N
```
private int N
```

W
```
private double[] W
```

A
```
private double[] A
```

simple
```
private boolean simple
```

t_method
```
private java.lang.String t_method
```

f_method
```
private java.lang.String f_method
```

output
```
private double[][] output
```

forward
```
private boolean forward
```

Constructor Detail

ChirpZTransform
```
public ChirpZTransform()
```

ChirpZTransform

public ChirpZTransform(double[][] output,
                       double[][] xX,
                       int MN,
                       double[] W,
                       double[] A,
                       boolean simple,
                       java.lang.String t_method,
                       java.lang.String f_method,
                       boolean forward)

Method Detail

test_compare_different_czt_methods
```
public void test_compare_different_czt_methods()
```
Starts the program.

assert_almost_equal

private void assert_almost_equal(double[][] actual,
                                 double[][] desired,
                                 int decimal,
                                 java.lang.String actualString,
                                 java.lang.String desiredString)

runAlgorithm
```
public void runAlgorithm()
```
Description copied from class: AlgorithmBase

Actually runs the algorithm. Implemented by inheriting algorithms.

Specified by:

runAlgorithm in class AlgorithmBase

_toeplitz_mult_pd

private double[][] _toeplitz_mult_pd(double[][] r,
                                     double[][] c,
                                     double[][] x,
                                     java.lang.String f_method)

_toeplitz_mult_ce

private double[][] _toeplitz_mult_ce(double[][] r,
                                     double[][] c,
                                     double[][] x,
                                     java.lang.String f_method)

_skew_circulant_multiply

private double[][] _skew_circulant_multiply(double[][] c,
                                            double[][] x,
                                            java.lang.String f_method)

_circulant_multiply

private double[][] _circulant_multiply(double[][] corg,
                                       double[][] xorg,
                                       java.lang.String f_method)

_fft

private double[][] _fft(double[][] x)

_ifft

private double[][] _ifft(double[][] y)

log2
```
private double log2(double input)
```

toeplitz

private double[][][] toeplitz(double[][] c,
                              double[][] r)

zabs
```
private double zabs(double zr,
                    double zi)
```
zabs computes the absolute value or magnitude of a double precision complex variable zr + j*zi.

Parameters:

zr - double

zi - double

Returns:

double

zpow

private void zpow(double zr,
                  double zi,
                  double a,
                  double[] br,
                  double[] bi,
                  int[] ierr)

b = z**a = exp(a*log(z))

Parameters:: zr -; zi -; a -; br -; bi -; ierr -

zlog

private void zlog(double ar,
                  double ai,
                  double[] br,
                  double[] bi,
                  int[] ierr)

complex logarithm b = clog(a).

Parameters:: ar - double; ai - double; br - double[]; bi - double[]; ierr - int[] ierr = 0, normal return ierr = 1, z = cmplx(0.0, 0.0)

zexp

private void zexp(double ar,
                  double ai,
                  double[] br,
                  double[] bi)

complex exponential function b = exp(a).

Parameters:: ar - double; ai - double; br - double[]; bi - double[]

zdiv

private void zdiv(double ar,
                  double ai,
                  double br,
                  double bi,
                  double[] cr,
                  double[] ci)

complex divide c = a/b.

Parameters:: ar - double; ai - double; br - double; bi - double; cr - double[]; ci - double[]

zmlt

private void zmlt(double ar,
                  double ai,
                  double br,
                  double bi,
                  double[] cr,
                  double[] ci)

complex multiply c = a * b.

Parameters:: ar - double; ai - double; br - double; bi - double; cr - double[]; ci - double[]

_signal_model

private double[] _signal_model(double[] tt)

_czt

private void _czt(double[][] output,
                  double[][] x,
                  int M,
                  double[] W,
                  double[] A)

Class ChirpZTransform

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Field Summary

Fields inherited from class gov.nih.mipav.model.algorithms.AlgorithmBase

Fields inherited from class java.lang.Thread

Constructor Summary

Method Summary

Methods inherited from class gov.nih.mipav.model.algorithms.AlgorithmBase

Methods inherited from class java.lang.Thread

Methods inherited from class java.lang.Object

Field Detail

UI

xX

x

X

MN

M

N

W

A

simple

t_method

f_method

output

forward

Constructor Detail

ChirpZTransform

ChirpZTransform

Method Detail

test_compare_different_czt_methods

assert_almost_equal

runAlgorithm

_toeplitz_mult_pd

_toeplitz_mult_ce

_skew_circulant_multiply

_circulant_multiply

_fft

_ifft

log2

toeplitz

zabs

zpow

zlog

zexp

zdiv

zmlt

_signal_model

_czt