matplotlib · jklymak · Dec 17, 2019 · Dec 16, 2019
diff --git a/examples/text_labels_and_annotations/tex_demo.py b/examples/text_labels_and_annotations/tex_demo.py
@@ -1,7 +1,7 @@
 """
-=================================
-Rendering math equation using TeX
-=================================
+==================================
+Rendering math equations using TeX
+==================================
 
 You can use TeX to render all of your matplotlib text if the rc
 parameter ``text.usetex`` is set.  This works currently on the agg and ps
@@ -30,4 +30,64 @@
 ax.set_ylabel('\\textit{Velocity (\N{DEGREE SIGN}/sec)}', fontsize=16)
 ax.set_title(r'\TeX\ is Number $\displaystyle\sum_{n=1}^\infty'
              r'\frac{-e^{i\pi}}{2^n}$!', fontsize=16, color='r')
+
+#############################################################################
+# A more complex example.
+
+fig, ax = plt.subplots()
+# interface tracking profiles
+N = 500
+delta = 0.6
+X = np.linspace(-1, 1, N)
+ax.plot(X, (1 - np.tanh(4 * X / delta)) / 2,    # phase field tanh profiles
+        X, (1.4 + np.tanh(4 * X / delta)) / 4, "C2",  # composition profile
+        X, X < 0, "k--")                        # sharp interface
+
+# legend
+ax.legend(("phase field", "level set", "sharp interface"),
+          shadow=True, loc=(0.01, 0.48), handlelength=1.5, fontsize=16)
+
+# the arrow
+ax.annotate("", xy=(-delta / 2., 0.1), xytext=(delta / 2., 0.1),
+            arrowprops=dict(arrowstyle="<->", connectionstyle="arc3"))
+ax.text(0, 0.1, r"$\delta$",
+        color="black", fontsize=24,
+        horizontalalignment="center", verticalalignment="center",
+        bbox=dict(boxstyle="round", fc="white", ec="black", pad=0.2))
+
+# Use tex in labels
+ax.set_xticks([-1, 0, 1])
+ax.set_xticklabels(["$-1$", r"$\pm 0$", "$+1$"], color="k", size=20)
+
+# Left Y-axis labels, combine math mode and text mode
+ax.set_ylabel(r"\bf{phase field} $\phi$", color="C0", fontsize=20)
+ax.set_yticks([0, 0.5, 1])
+ax.set_yticklabels([r"\bf{0}", r"\bf{.5}", r"\bf{1}"], color="k", size=20)
+
+# Right Y-axis labels
+ax.text(1.02, 0.5, r"\bf{level set} $\phi$",
+        color="C2", fontsize=20, rotation=90,
+        horizontalalignment="left", verticalalignment="center",
+        clip_on=False, transform=ax.transAxes)
+
+# Use multiline environment inside a `text`.
+# level set equations
+eq1 = (r"\begin{eqnarray*}"
+       r"|\nabla\phi| &=& 1,\\"
+       r"\frac{\partial \phi}{\partial t} + U|\nabla \phi| &=& 0 "
+       r"\end{eqnarray*}")
+ax.text(1, 0.9, eq1, color="C2", fontsize=18,
+        horizontalalignment="right", verticalalignment="top")
+
+# phase field equations
+eq2 = (r"\begin{eqnarray*}"
+       r"\mathcal{F} &=& \int f\left( \phi, c \right) dV, \\ "
+       r"\frac{ \partial \phi } { \partial t } &=& -M_{ \phi } "
+       r"\frac{ \delta \mathcal{F} } { \delta \phi }"
+       r"\end{eqnarray*}")
+ax.text(0.18, 0.18, eq2, color="C0", fontsize=16)
+
+ax.text(-1, .30, r"gamma: $\gamma$", color="r", fontsize=20)
+ax.text(-1, .18, r"Omega: $\Omega$", color="b", fontsize=20)
+
 plt.show()
diff --git a/examples/text_labels_and_annotations/usetex_demo.py b/examples/text_labels_and_annotations/usetex_demo.py