spectrochempy.hann

hann(dataset, **kwargs)[source]

Return a Hann window.

For multidimensional NDDataset, the apodization is by default performed on the last dimension.

The data in the last dimension MUST be time-domain or dimensionless, otherwise an error is raised.

Functional form of apodization window :

\[w(n) = \alpha - (1 - \alpha) \cos(\frac{2\pi{n}}{M-1}) \qquad 0 \leq n \leq M-1\]

where M is the number of point of the input dataset and \(\alpha\) = 0.5

Parameters:

  • dataset (NDDataset) – Input dataset.

  • **kwargs – Optional keyword parameters (see Other Parameters).

Returns:

  • apodized – Dataset.

  • apod_arr – The apodization array only if ‘retapod’ is True.

Other Parameters:

  • dim (str or int, keyword parameter, optional, default=’x’.) – Specify on which dimension to apply the apodization method. If dim is specified as an integer it is equivalent to the usual axis numpy parameter.

  • inv (bool, keyword parameter, optional, default=False.) – True for inverse apodization.

  • rev (bool, keyword parameter, optional, default=False.) – True to reverse the apodization before applying it to the data.

  • inplace (bool, keyword parameter, optional, default=False.) – True if we make the transform inplace. If False, the function return a new dataset

  • retapod (bool, keyword parameter, optional, default=False) – True to return the apodization array along with the apodized object

See also

general_hamming, hamming