Colourful convert from xy chromaticity to RGB (sRGB)

ConsoleApp1.csproj

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    <PackageReference Include="Colourful" Version="3.0.0-beta1" />
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ConsoleApp1.sln

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Program.cs

using System.Linq;
using Colourful;

namespace ConsoleApp1
{
    internal class Program
    {
        private static readonly IColorConverter<xyChromaticity, RGBColor> ConverterXyToRgb = new ConverterBuilder().Fromxy(Illuminants.D65).ToRGB(RGBWorkingSpaces.sRGB).Build();
        private static readonly IColorConverter<RGBColor, xyChromaticity> ConverterRgbToXy = new ConverterBuilder().FromRGB(RGBWorkingSpaces.sRGB).Toxy(Illuminants.D65).Build();

        private static void Main()
        {
            // input xy
            var inputXy = new xyChromaticity(.735, .265); // xy [x=0.74, y=0.27]
            var outputRgb = ConvertXyToRgb(inputXy); // RGB [R=1, G=0, B=0]
            var inputXy2 = ConvertRgbToXy(outputRgb); // xy [x=0.64, y=0.33]
        }

        private static RGBColor ConvertXyToRgb(xyChromaticity chromaticity)
        {
            var rgbColor = ConverterXyToRgb.Convert(chromaticity); // RGB [R=2.38, G=-10.5, B=-0.64]

            // divide each channel by the largest value from R, G, B to have the maximum intensity
            // smaller values than 0 are trucated to 0
            var rgbChannelMaxValue = rgbColor.Vector.Max();
            var rgbColorNormalized = new RGBColor(rgbColor.Vector.Select(c => c < 0 ? 0 : c / rgbChannelMaxValue).ToArray());
            return rgbColorNormalized; // RGB [R=1, G=0, B=0]
        }
        
        private static xyChromaticity ConvertRgbToXy(RGBColor rgbColor)
        {
            var chromaticity = ConverterRgbToXy.Convert(rgbColor);
            return chromaticity;
        }
    }
}