R: Calculate (inverse) DFT using the FFT method

FFT {fftw} | R Documentation

## Calculate (inverse) DFT using the FFT method

### Description

see title

### Usage

    FFT(x, ..., plan, inverse=FALSE)
    IFFT(x, ..., plan, scale=TRUE)
    DCT(x, ..., plan, type=1, inverse=FALSE)
    IDCT(x, ..., plan, type=1, scale=TRUE)

### Arguments

`x` | (complex) vector to process
`...` | ignored
`plan` | FFTW plan, can be missing
`inverse` | perform inverse transform, provided for `fft` compatibility.
`scale` | scale results
`type` | type of DCT

### Author(s)

Olaf Mersmann <olafm@statistik.uni-dortmund.de>

### See Also

`planFFT`

### Examples

    n <- 2**16
    x <- rnorm(n)
    p <- planFFT(n)
    y <- FFT(x, plan=p)

    Mod(x - IFFT(FFT(x)))

[Package fftw version 1.0-6 Index]