

Ternary plots are tools for analyzing compositional data in the three-dimensional case. In game theory, it is often called a simplex plot. In population genetics, a triangle plot of genotype frequencies is called a de Finetti diagram. It is used in physical chemistry, petrology, mineralogy, metallurgy, and other physical sciences to show the compositions of systems composed of three species. It graphically depicts the ratios of the three variables as positions in an equilateral triangle.

Two ternary diagrams with matching axes can be joined at that axis to make a piper diagramĪ ternary plot, ternary graph, triangle plot, simplex plot, Gibbs triangle or de Finetti diagram is a barycentric plot on three variables which sum to a constant.
