The Math::FFT module provides an interface to various
Fast Fourier Transform (FFT) routines of the C routine of fft4g.c, 
available at http://momonga.t.u-tokyo.ac.jp/~ooura/fft.html.
The one-dimensional data sets, of size 2^n, are assumed
to be sampled at a constant rate.

The FFT methods available are
- cdft: Complex Discrete Fourier Transform
- rdft: Real Discrete Fourier Transform
- ddct: Discrete Cosine Transform
- ddst: Discrete Sine Transform
- dfct:  Cosine Transform of RDFT (Real Symmetric DFT)
- dfst:  Sine Transform of RDFT (Real Symmetric DFT)
as well as their inverses.

Also available are some methods to implement some common
applications of FFTs for real data sets. These are
- correl: Find the correlation between two data sets
- convlv: Find the convolution of one data set with another
- deconvlv: Find the deconvolution of one data set with another
- spctrm: Find the power spectrum of a data set, including
  application of a windowing function and segmentation of the data.

Finally, for convenience some common statistical methods are
included for analyzing real data sets. These are
- mean: Find the mean of a data set
- stdev: Find the standard deviation of a data set
- range: Find the minimum and maximum values of a data set
- median: Find the median of a data set
- rms: Find the root mean square of a data set

The C code for the FFT routines of fft4g.c is copyrighted 1996-99 
by Takuya OOURA. The file arrays.c included here to handle
passing arrays to and from C comes from the PGPLOT module
of Karl Glazebrook <kgb@aaoepp.aao.gov.au>. The perl 
interface of the Math::FTT module is Copyright 2000,2005 
by Randy Kobes <r.kobes@uwinnipeg.ca>, and may be
distributed under the same terms as Perl itself.