Overview: This computes an the DFT of an input array.

Detailed Description: This module uses a radix-2 Fast Fourier Transform to compue the Discrete Fourier Transform of a 1-dimensional input array. If the input is not a power-of-2 in length, the input will automatically be zeropadded to the next appropriate power of two length. The module outputs the entire spectrum [0, 2pi). To extract only the nonredundant part of the conjugate-symmetric spectrum, use the org.imirsel.m2k.util.Truncate1DDoubleArray Module. An inverse option is also given with this module. Note that it will only invert REAL spectra (useful for autocorrelation).