colour.phenomena.sky_luminance_gradation_CIE2003#

colour.phenomena.sky_luminance_gradation_CIE2003(Z: ArrayLike, a: ArrayLike, b: ArrayLike) → NDArrayFloat[source]#

Compute the CIE Standard General Sky luminance gradation function \(\varphi(Z)\) at the given zenith angle \(Z\).

Parameters:

  • Z (ArrayLike) – Zenith angle \(Z\) in radians.

  • a (ArrayLike) – Gradation parameter \(a\).

  • b (ArrayLike) – Gradation parameter \(b\).

Returns:

Luminance gradation \(\varphi(Z)\).

Return type:

numpy.ndarray

References

[]

Examples

>>> sky_luminance_gradation_CIE2003(0, 4.0, -0.70)
np.float64(2.9863412...)
>>> sky_luminance_gradation_CIE2003(
...     np.pi / 2, 4.0, -0.70
... )
np.float64(1.0)