<h2>org.das2.qds.math.fft.GeneralFFT</h2><p>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.</p> <h2>GeneralFFT( int n, boolean doublePrecision, boolean real )</h2> <p>Initialize the FFT object by constructing wave tables that can be repeatly used.</p> <hr> <a name="invTransform"></a> <h2>invTransform</h2> invTransform( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/ComplexArray/Double.html'>org.das2.qds.math.fft.ComplexArray.Double</a> data ) → void <p>perform the inverse transform on the array in situ.</p> <h3>Parameters</h3> data - a ComplexArray.Double <h3>Returns:</h3> void (returns nothing) <br><br> <a href="https://github.com/autoplot/dev/search?q=invTransform&unscoped_q=invTransform">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/qds/math/fft/GeneralFFT.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/qds/math/fft/GeneralFFT.html#invTransform">[view on old javadoc]</a> <a href="https://sourceforge.net/p/autoplot/code/HEAD/tree/autoplot/trunk/QDataSet/src/org/das2/qds/math/fft/GeneralFFT.java#l113">[view source]</a> <br> <br> invTransform( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/ComplexArray/Float.html'>org.das2.qds.math.fft.ComplexArray.Float</a> data ) → void<br> <hr> <a name="newDoubleFFT"></a> <h2>newDoubleFFT</h2> newDoubleFFT( int n ) → <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/GeneralFFT.html'>org.das2.qds.math.fft.GeneralFFT</a> <p>creates an FFT object that operates on a ComplexArray.Double of n elements.</p> <h3>Parameters</h3> n - an int <h3>Returns:</h3> org.das2.qds.math.fft.GeneralFFT <br><br> <a href="https://github.com/autoplot/dev/search?q=newDoubleFFT&unscoped_q=newDoubleFFT">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/qds/math/fft/GeneralFFT.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/qds/math/fft/GeneralFFT.html#newDoubleFFT">[view on old javadoc]</a> <a href="https://sourceforge.net/p/autoplot/code/HEAD/tree/autoplot/trunk/QDataSet/src/org/das2/qds/math/fft/GeneralFFT.java#l74">[view source]</a> <br> <br> <hr> <a name="newFloatFFT"></a> <h2>newFloatFFT</h2> newFloatFFT( int n ) → <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/GeneralFFT.html'>org.das2.qds.math.fft.GeneralFFT</a> <p>creates an FFT object that operates on a ComplexArray.Float of n elements.</p> <h3>Parameters</h3> n - an int <h3>Returns:</h3> org.das2.qds.math.fft.GeneralFFT <br><br> <a href="https://github.com/autoplot/dev/search?q=newFloatFFT&unscoped_q=newFloatFFT">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/qds/math/fft/GeneralFFT.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/qds/math/fft/GeneralFFT.html#newFloatFFT">[view on old javadoc]</a> <a href="https://sourceforge.net/p/autoplot/code/HEAD/tree/autoplot/trunk/QDataSet/src/org/das2/qds/math/fft/GeneralFFT.java#l67">[view source]</a> <br> <br> <hr> <a name="size"></a> <h2>size</h2> size( ) → int <p>return the number of points in the fft.</p> <h3>Returns:</h3> the number of points in the fft. <br><br> <a href="https://github.com/autoplot/dev/search?q=size&unscoped_q=size">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/qds/math/fft/GeneralFFT.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/qds/math/fft/GeneralFFT.html#size">[view on old javadoc]</a> <a href="https://sourceforge.net/p/autoplot/code/HEAD/tree/autoplot/trunk/QDataSet/src/org/das2/qds/math/fft/GeneralFFT.java#l130">[view source]</a> <br> <br> <hr> <a name="transform"></a> <h2>transform</h2> transform( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/ComplexArray/Double.html'>org.das2.qds.math.fft.ComplexArray.Double</a> data ) → void <p>perform the forward transform on the array in situ.</p> <h3>Parameters</h3> data - a ComplexArray.Double <h3>Returns:</h3> void (returns nothing) <br><br> <a href="https://github.com/autoplot/dev/search?q=transform&unscoped_q=transform">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/qds/math/fft/GeneralFFT.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/qds/math/fft/GeneralFFT.html#transform">[view on old javadoc]</a> <a href="https://sourceforge.net/p/autoplot/code/HEAD/tree/autoplot/trunk/QDataSet/src/org/das2/qds/math/fft/GeneralFFT.java#l81">[view source]</a> <br> <br> transform( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/qds/math/fft/ComplexArray/Float.html'>org.das2.qds.math.fft.ComplexArray.Float</a> data ) → void<br>