colour.yellowness#

colour.yellowness(XYZ: ArrayLike, method: Union[Literal['ASTM D1925', 'ASTM E313', 'ASTM E313 Alternative'], str] = 'ASTM E313', **kwargs: Any) → FloatingOrNDArray[source]#

Return the yellowness \(W\) using given method.

Parameters:

  • XYZ (ArrayLike) – CIE XYZ tristimulus values of the sample.

  • method (Union[Literal['ASTM D1925', 'ASTM E313', 'ASTM E313 Alternative'], str]) – Computation method.

  • C_XZ – {colour.colorimetry.yellowness_ASTME313()}, Coefficients \(C_X\) and \(C_Z\) for the CIE 1931 2 Degree Standard Observer and CIE 1964 10 Degree Standard Observer and CIE Illuminant C and CIE Standard Illuminant D65.

  • kwargs (Any) –

Returns:

Yellowness \(Y\).

Return type:

np.floating or numpy.ndarray

Notes

Domain

Scale - Reference

Scale - 1

XYZ

[0, 100]

[0, 1]

Range

Scale - Reference

Scale - 1

YI

[0, 100]

[0, 1]

References

[ASTMInternational15b], [XRitePantone12]

Examples

>>> XYZ = np.array([95.00000000, 100.00000000, 105.00000000])
>>> yellowness(XYZ)  
4.3400000...
>>> yellowness(XYZ, method="ASTM E313 Alternative")  
11.0650000...
>>> yellowness(XYZ, method="ASTM D1925")  
10.2999999...