add ref

Author: luke

examples/animation/simple_anim.py

@@ -3,6 +3,7 @@
 Animated line plot
 ==================
 
+Output generate via :ref:`matplotlib.animation.Animation.to_jshtml`.
 """
 
 import numpy as np
@@ -11,7 +12,7 @@
 
 fig, ax = plt.subplots()
 
-x = np.arange(0, 2*np.pi, 0.01)
+x = np.arange(0, 2 * np.pi, 0.01)
 line, = ax.plot(x, np.sin(x))