ifft¶

Purpose:

Transform function in frequency domain to time domain.

Syntax:

x = ifft(y)
x = ifft(y, N)

Description:

ifft transforms a function in the frequency domain to a function in the time domain.

The function to be transformed is given in the vector y. Each row in y contains Fourier terms in the interval \(-\infty \leq \omega \leq +\infty\).

The ifft command can be used with one or two input arguments. The scalar variable N can be used to specify the number of frequencies used in the Fourier transform. The size of the output vector in this case will be equal to N. See also the description of the command fft.

The inverse Fourier coefficients \(x(j)\), stored in the variable x, are computed according to

\[x(j) = \frac{1}{N} \sum_{k=1}^N y(k) \omega_N^{-(j-1)(k-1)},\]

where

\[\omega_N = e^{-2 \pi i / N}.\]

Note

This is a MATLAB built-in function.

See also:

fft