I have a data file with results from a simple personality test, where a total of 84 points are distributed among three colors, red, green and blue. A sample score could be red=17, blue=39 and green=28.
I want to plot each persons result as a dot in a chart, but I want to avoid using a 3d coordinate system. How could I do this? Notice that the values for each of the colors would never be negative.
Does it exist some kind of triangular coordinate system? Is there already a solution to my problem in the subject of mathematics?