fftfreq

Contents

fftfreq#

class brainunit.fft.fftfreq(n, d=1.0, *, dtype=None, device=None, **kwargs)#

Return sample frequencies for the discrete Fourier transform.

Unit-aware implementation of numpy.fft.fftfreq(). When d carries a time unit, the returned frequencies carry the corresponding reciprocal (frequency) unit.

Parameters:
  • n (int) – Window length (number of samples in the FFT).

  • d (saiunit.Quantity | Array | ndarray | bool | number | bool | int | float | complex) – Sample spacing. If a Quantity with a time unit is given, the output will carry the matching frequency unit (e.g. second -> hertz).

  • dtype (str | type[Any] | dtype | SupportsDType | None) – Desired data-type for the output.

  • device (Device | Sharding | None) – Device on which to place the output.

Returns:

Array of length n containing sample frequencies.

Return type:

saiunit.Quantity | Array | ndarray | bool | number | bool | int | float | complex

See also

saiunit.fft.rfftfreq

Frequencies for rfft() / irfft().

Examples

>>> import saiunit as u
>>> import saiunit.fft as sufft
>>> freqs = sufft.fftfreq(4, 1.0 * u.second)