Tick locators

Tick locators can be given both for major and minor ticks in the same way as Matplotlib. Gridlines for minor ticks can be also plotted.

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.ticker import MultipleLocator, AutoMinorLocator
import mpltern

ax = plt.subplot(projection="ternary")

np.random.seed(19680801)
t, l, r = np.random.dirichlet(alpha=(2.0, 4.0, 8.0), size=128).T

ax.scatter(t, l, r, s=64.0, c="C1", edgecolors="k", alpha=0.6)

ax.set_tlabel("$x_1$")
ax.set_llabel("$x_2$")
ax.set_rlabel("$x_3$")

ax.taxis.set_major_locator(MultipleLocator(0.25))
ax.laxis.set_major_locator(MultipleLocator(0.20))
ax.raxis.set_major_locator(MultipleLocator(0.10))

ax.laxis.set_minor_locator(MultipleLocator(0.1))
ax.raxis.set_minor_locator(AutoMinorLocator(5))

ax.grid(axis='t')
ax.grid(axis='l', which='minor', linestyle='--')
ax.grid(axis='r', which='both', linestyle=':')

plt.show()