The **cieuv2cct** function calculates the Correlated Colour Temperature (CCT) T_{\mathrm{cp}} from given CIE 1960 chromaticity coordinates u and v, also known as Uniform Colour Space (UCS). See also: ciexy2cct. Any errors in the data set or in results generated with the Lighting Toolbox are not in the liability of the CIE nor me, see licence.

Usage:

Tcp = cieuv2cct(u,v,'method')

Where:

Parameter | Description |

`Tcp` | Is a scalar or vector containing the resulting Correlated Colour Temperature(s) (CCT) in K. |

`u and v` | Are the input scalars or vectors containing the CIE 1960 chromaticity coordinates u and v. |

`'method'` | Specifies the determination method:‘Robertson’: (default) Robertson’s calculation algorithm, formerly the only recommended algorithm by the CIE. This method is fast and quite accurate.‘exact’: shortest distance method as described in CIE 15:2018, very accurate but comparably slow. Results may vary with different implementation methods. Both methods return NaN if the colour coordinates lie outside the meaningful interval of \Delta uv < 0.05 from the planckian locus in CIE 1960 chromaticity diagram. |

**Examples**

**Correlated Colour Temperature T_{\mathrm{cp}} for u = 0.2308 and y = 0.2825 using the default ‘Robertson’ method:**

u = 0.2308; v = 0.2825; Tcp = cieuv2cct(u,v)

Result:

Tcp = 7513

**Correlated Colour Temperature T_{\mathrm{cp}} for r u = 0.2308 and y = 0.2825 using ‘exact’ method:**

u = 0.2308; v = 0.2825; Tcp = cieuv2cct(u,v,'exact')

Result:

Tcp = 7519.3

**Correlated Colour Temperature T_{\mathrm{cp}} for several chromaticity coordinates using ‘Robertson’ method:**

u = linspace(0.25,0.30,5) v = linspace(0.25,0.30,5) Tcp = cieuv2cct(u,v,'Robertson')

Result:

u = 0.2500 0.2625 0.2750 0.2875 0.3000 v = 0.2500 0.2625 0.2750 0.2875 0.3000 Tcp = 50060 7679 3202 2498 2169

**References**

`Colorimetry, 4th Edition. Commission International de l’Éclairage (CIE), Vienna Austria, 2018, ISBN: 978-3-902842-13-8 , (DOI: 10.25039/TR.015.2018).`

`Computation of Correlated Color Temperature and Distribution Temperature. In: Journal of the Optical Society of America, vol. 58, no. 11, pp. 1528-1535, 1968, (DOI: 10.1364/JOSA.58.001528).`