Function white_point_from_temperature 

const fn white_point_from_temperature(temp_k: i32) -> XyY

From lcms: cmsWhitePointFromTemp tempK must be >= 4000. and <= 25000. Invalid values of tempK will return (x,y,Y) = (-1.0, -1.0, -1.0) similar to argyll: icx_DTEMP2XYZ()