num::spectral::ifft

Defined in header <spectral/fft.hpp>

void ifft(const vec<cplx> &in, vec<cplx> &out, fft_backend b = default_fft_backend);

Compute unnormalized inverse 1D Fast Fourier Transform \(x_j = \sum_{k=0}^{n-1} X_k e^{+2\pi i j k / n}\).

Note that dividing by \(n\) is required to recover the original amplitude.

Parameters

• in: Input complex spectrum of length \(n\).
• out: Output reconstructed complex vector (size \(n\)).
• b: FFT backend tag.

See also

fft, irfft