Merge pull request matplotlib#8741 from anntzer/docs-cleanups

Simplify some examples.

Author: dstansby

doc/faq/howto_faq.rst

@@ -357,13 +357,10 @@ some ratio which controls the ratio::
 
   ax = fig.add_subplot(111, aspect='equal')
 
-
-
 .. htmlonly::
 
-    See :ref:`sphx_glr_gallery_subplots_axes_and_figures_equal_aspect_ratio.py` for a complete
-    example.
-
+    See :ref:`sphx_glr_gallery_pylab_examples_axis_equal_demo.py` for a
+    complete example.
 
 .. _howto-twoscale:
 

examples/pylab_examples/axis_equal_demo.py

@@ -3,40 +3,32 @@
 Axis Equal Demo
 ===============
 
-This example is only interesting when run in interactive mode.
-
 """
 
-
 import matplotlib.pyplot as plt
 import numpy as np
 
-# Plot circle or radius 3
+# Plot circle of radius 3.
 
 an = np.linspace(0, 2*np.pi, 100)
+fig, axs = plt.subplots(2, 2)
+
+axs[0, 0].plot(3*np.cos(an), 3*np.sin(an))
+axs[0, 0].set_title('not equal, looks like ellipse', fontsize=10)
+
+axs[0, 1].plot(3*np.cos(an), 3*np.sin(an))
+axs[0, 1].axis('equal')
+axs[0, 1].set_title('equal, looks like circle', fontsize=10)
+
+axs[1, 0].plot(3*np.cos(an), 3*np.sin(an))
+axs[1, 0].axis('equal')
+axs[1, 0].axis([-3, 3, -3, 3])
+axs[1, 0].set_title('still a circle, even after changing limits', fontsize=10)
+
+axs[1, 1].plot(3*np.cos(an), 3*np.sin(an))
+axs[1, 1].set_aspect('equal', 'box')
+axs[1, 1].set_title('still a circle, auto-adjusted data limits', fontsize=10)
 
-plt.subplot(221)
-plt.plot(3*np.cos(an), 3*np.sin(an))
-plt.title('not equal, looks like ellipse', fontsize=10)
-
-plt.subplot(222)
-plt.plot(3*np.cos(an), 3*np.sin(an))
-plt.axis('equal')
-plt.title('equal, looks like circle', fontsize=10)
-
-plt.subplot(223)
-plt.plot(3*np.cos(an), 3*np.sin(an))
-plt.axis('equal')
-plt.axis([-3, 3, -3, 3])
-plt.title('looks like circle, even after changing limits', fontsize=10)
-
-plt.subplot(224)
-plt.plot(3*np.cos(an), 3*np.sin(an))
-plt.axis('equal')
-plt.axis([-3, 3, -3, 3])
-plt.plot([0, 4], [0, 4])
-plt.title('still equal after adding line', fontsize=10)
-
-plt.tight_layout()
+fig.tight_layout()
 
 plt.show()

examples/pylab_examples/vline_hline_demo.py

@@ -7,26 +7,20 @@
 """
 
 import matplotlib.pyplot as plt
-from matplotlib.transforms import blended_transform_factory as btf
 import numpy as np
 
 
-def f(t):
-    s1 = np.sin(2 * np.pi * t)
-    e1 = np.exp(-t)
-    return np.abs(s1 * e1) + .05
-
 t = np.arange(0.0, 5.0, 0.1)
-s = f(t)
+s = np.exp(-t) + np.sin(2 * np.pi * t) + 1
 nse = np.random.normal(0.0, 0.3, t.shape) * s
 
-fig = plt.figure(figsize=(12, 6))
-vax = fig.add_subplot(121)
-hax = fig.add_subplot(122)
+fig, (vax, hax) = plt.subplots(1, 2, figsize=(12, 6))
 
 vax.plot(t, s + nse, '^')
 vax.vlines(t, [0], s)
-vax.vlines([1, 2], 0, 1, transform=btf(vax.transData, vax.transAxes), colors='r')
+# By using ``transform=vax.get_xaxis_transform()`` the y coordinates are scaled
+# such that 0 maps to the bottom of the axes and 1 to the top.
+vax.vlines([1, 2], 0, 1, transform=vax.get_xaxis_transform(), colors='r')
 vax.set_xlabel('time (s)')
 vax.set_title('Vertical lines demo')
 

examples/subplots_axes_and_figures/equal_aspect_ratio.py

@@ -156,7 +156,6 @@
     'ellipse_collection.py',
     'ellipse_demo.py',
     'ellipse_rotated.py',
-    'equal_aspect_ratio.py',
     'errorbar_limits.py',
     'fancyarrow_demo.py',
     'fancybox_demo.py',