colour.algebra.spow¶

colour.algebra.spow(a, p)[source]¶

Raises given array \(a\) to the power \(p\) as follows: \(sign(a) * |a|^p\).

This avoids NaNs generation when array \(a\) is negative and the power \(p\) is fractional.

Parameters:	a (numeric or array_like) – Array \(a\). p (numeric or array_like) – Power \(p\).
Returns:	Array \(a\) safely raised to the power \(p\).
Return type:	numeric or ndarray

Examples

>>> np.power(-2, 0.15)
nan
>>> spow(-2, 0.15)  # doctest: +ELLIPSIS
-1.1095694...
>>> spow(0, 0)
0.0