I’m trying to generate a ternary plot with contour inside, my variable conc1, conc2, conc3 in term of ZIP, but I want to plot the absolute on the sides of the triangle, however, my code plot these values in uneven spacing:

I’m trying to generate a ternary plot with contour inside, my variable conc1, conc2, conc3 in term of ZIP, but I want to plot the absolute on the sides of the triangle, however, my code plot these values in uneven spacing: