colour.XYZ_to_xy#

colour.XYZ_to_xy(XYZ: ArrayLike, illuminant: ArrayLike = CCS_ILLUMINANTS['CIE 1931 2 Degree Standard Observer']['D65']) → NDArrayFloat[source]#

Return the CIE xy chromaticity coordinates from given CIE XYZ tristimulus values.

Parameters:

  • XYZ (ArrayLike) – CIE XYZ tristimulus values.

  • illuminant (ArrayLike) – Reference illuminant chromaticity coordinates.

Returns:

CIE xy chromaticity coordinates.

Return type:

numpy.ndarray

Notes

Domain

Scale - Reference

Scale - 1

XYZ

[0, 1]

[0, 1]

References

[Wikipedia05d]

Examples

>>> XYZ = np.array([0.20654008, 0.12197225, 0.05136952])
>>> XYZ_to_xy(XYZ)  
array([ 0.5436955...,  0.3210794...])