TernaryDiagrams

This package exports a few Makie recipes that can be used to construct a (relatively quick and dirty) ternary plot.

In all the examples that follow, it is assumed that a1[i] + a2[i] + a3[i] = 1. If applicable, w[i] corresponds to the weight associated with the point (a1[i], a2[i], a3[i]) for each index i in the dataset. If you would like to load a test dataset, use test/data.jld2, which can be opened with JLD2.jl. The file contains a1, a2, a3 and mus, with the latter being weights associated with the data points. See the file temp.jl for an example of its usage.

The ternary axis

fig = Figure();
ax = Axis(fig[1, 1]);

ternaryaxis!(
    ax; 
    labelx = "a1",
    labely = "a2",
    labelz = "a3",
    # more options available, check out attributes with ?ternaryaxis (same for other plot functions)
    #= Note 
    Depending on the length of the axis labels, they may seem unaligned. 
    Use the kwarg arrow_label_rotation_adjustment to rotate them slightly. 
    For longer labels, use a value closer to 1 (trial and error it).
    =#
)

# the triangle is drawn from (0,0) to (0.5, sqrt(3)/2) to (1,0).
xlims!(ax, -0.2, 1.2) # to center the triangle and allow space for the labels
ylims!(ax, -0.3, 1.1)
hidedecorations!(ax) # to hide the axis decorations
fig

Ternary lines

fig = Figure();
ax = Axis(fig[1, 1]);

ternaryaxis!(ax);
ternarylines!(ax, a1, a2, a3; color = :blue)

xlims!(ax, -0.2, 1.2)
ylims!(ax, -0.3, 1.1)
hidedecorations!(ax)
fig

Ternary scatter

fig = Figure();
ax = Axis(fig[1, 1]);

ternaryaxis!(ax);
ternaryscatter!(
    ax,
    a1,
    a2,
    a3;
    color = [get(ColorSchemes.Spectral, w, extrema(ws)) for w in ws],
    marker = :circle,
    markersize = 20,
)

xlims!(ax, -0.2, 1.2)
ylims!(ax, -0.3, 1.1)
hidedecorations!(ax)
fig

Ternary contours

fig = Figure();
ax = Axis(fig[1, 1]);

ternarycontour!(
    ax,
    a1,
    a2,
    a3,
    ws;
    levels = 5,
    linewidth = 4,
    color = nothing,
    colormap = reverse(ColorSchemes.Spectral),
    pad_data = true,
)

ternaryaxis!(ax);

xlims!(ax, -0.2, 1.2)
ylims!(ax, -0.3, 1.1)
hidedecorations!(ax)
fig

Ternary filled contours

Note: ternarycontour uses a different Delaunay triangulation scheme to ternarycontourf (the former is made by me, while the latter essentially calls tricontourf from Makie. from Makie internally).

fig = Figure();
ax = Axis(fig[1, 1]);
ternarycontourf!(ax, a1, a2, a3, ws; levels = 10)
ternaryaxis!(ax);
xlims!(ax, -0.2, 1.2)
ylims!(ax, -0.3, 1.1)
hidedecorations!(ax)
fig

Long term plans

If you use this package and run into issues, please let me know! I am planning on extending the package to make a ternary plot axis instead of co-opting the regular 2D axis. Before that stage though, I would like to sort out any bugs I currently have implemented. So let me know what you think!