[rauhallinen]

I had a project where I had to convert absorption spectrum of a liquid sample into a colour. It was one of those "Just do this quick, it doesn't have to be perfect" type of things where I didn't get a chance to really understand it. I was baffled how many standards and technicalities there is behind a seemingly simple thing.

[aaaaaaaaaaab]

Take the dot product between 1 - your spectrum and the CIE XYZ color matching functions, then convert it to sRGB or any other color space of your choice.