swectral.vegeind.pad#

swectral.vegeind.pad(spec_array, order, padding='edge', axis=0)[source]#

Compute PAD (Derivative Pseudo-Absorption) of a 2D array-like collection of 1D spectral data series. The calculation is based on:

George Alan Blackburn,
Quantifying Chlorophylls and Caroteniods at Leaf and Canopy Scales: An Evaluation of Some Hyperspectral Approaches,
Remote Sensing of Environment,
Volume 66, Issue 3,
1998,
Pages 273-285,
ISSN 0034-4257,
https://doi.org/10.1016/S0034-4257(98)00059-5.

Parameters:

spec_array2D array_like, shape (n_samples, n_features)

2D array-like of 1D spectral data series.

orderint

Order of the derivative.

paddingint or float or str or None, optional

Boundary padding strategy for derivative arrays. Choose between:

‘nan’ – pad with NaN.
‘edge’ – pad with edge values.
numeric – pad with the specified constant.
None – no padding.

If None is used, or for n-th order derivatives, the output length will be reduced by 2n along the computation axis. The default is ‘edge’.

axisint, optional

Axis representing the spectral dimension. Must be 0 or 1.

If 0, each row represents a sample spectrum. The default is 0.

Returns:

np.ndarray: Derivative pseudo-absorptions.

Return type:

ndarray