Question

Has anyone written a fast Fourier transform extension for R that modifies R’s native fft() function so that when you call for the inverse fast Fourier transform you don’t have to divide by the length of the fast Fourier transform output? I’m doing a lot of FFTs and inverse FFTs and having to do this every time is getting annoying.

Answer 1

You could write your own:

fftinv <- function( x ) { fft( x, inverse=TRUE ) / length( x ) }