colour.temperature.CCT_to_xy_Hernandez1999

colour.temperature.CCT_to_xy_Hernandez1999(CCT: ArrayLike, optimisation_kwargs: dict | None = None) → NDArrayFloat

Compute the CIE xy chromaticity coordinates from the specified correlated colour temperature \(T_{cp}\) using Hernandez-Andres et al. (1999) method.

Parameters:

• CCT (ArrayLike) – Correlated colour temperature \(T_{cp}\).

• optimisation_kwargs (dict | None) – Inversion parameters forwarded to colour.temperature.solve_xy_Newton(). Accepted keys are x0, reference_xy, reference_weight, newton_iterations, backtrack_iterations and tolerance.

Returns:

CIE xy chromaticity coordinates.

Return type:

numpy.ndarray

Warning

Hernandez-Andres et al. (1999) method for computing CIE xy chromaticity coordinates from the specified correlated colour temperature is not a bijective function and might produce unexpected results. It is provided for consistency with other correlated colour temperature computation methods but should be avoided for practical applications. The current implementation seeds a Tikhonov- regularised damped Gauss-Newton iteration anchored to the CIE Standard Illuminant D65 chromaticity coordinates, vectorised across all input samples.

References

[HernandezAndresLR99]

Examples

>>> CCT_to_xy_Hernandez1999(6500.7420431786531)
array([0.3127..., 0.329...])