matplotlib
diff --git a/‎examples/pylab_examples/contourf_demo.py
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+45-25Lines changed: 45 additions & 25 deletions b/‎examples/pylab_examples/contourf_demo.py
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+45-25Lines changed: 45 additions & 25 deletions
@@ -1,68 +1,70 @@
 #!/usr/bin/env python
-from pylab import *
+import numpy as np
+import matplotlib.pyplot as plt
+
 origin = 'lower'
 #origin = 'upper'
 
 delta = 0.025
 
-x = y = arange(-3.0, 3.01, delta)
-X, Y = meshgrid(x, y)
-Z1 = bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0)
-Z2 = bivariate_normal(X, Y, 1.5, 0.5, 1, 1)
+x = y = np.arange(-3.0, 3.01, delta)
+X, Y = np.meshgrid(x, y)
+Z1 = plt.mlab.bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0)
+Z2 = plt.mlab.bivariate_normal(X, Y, 1.5, 0.5, 1, 1)
 Z = 10 * (Z1 - Z2)
 
 nr, nc = Z.shape
 
 # put NaNs in one corner:
-Z[-nr//6:, -nc//6:] = nan
+Z[-nr//6:, -nc//6:] = np.nan
 # contourf will convert these to masked
 
 
-Z = ma.array(Z)
+Z = np.ma.array(Z)
 # mask another corner:
-Z[:nr//6, :nc//6] = ma.masked
+Z[:nr//6, :nc//6] = np.ma.masked
 
 # mask a circle in the middle:
-interior = sqrt((X**2) + (Y**2)) < 0.5
-Z[interior] = ma.masked
+interior = np.sqrt((X**2) + (Y**2)) < 0.5
+Z[interior] = np.ma.masked
 
 
 # We are using automatic selection of contour levels;
 # this is usually not such a good idea, because they don't
 # occur on nice boundaries, but we do it here for purposes
 # of illustration.
-CS = contourf(X, Y, Z, 10, # [-1, -0.1, 0, 0.1],
+CS = plt.contourf(X, Y, Z, 10, # [-1, -0.1, 0, 0.1],
                         #alpha=0.5,
-                        cmap=cm.bone,
+                        cmap=plt.cm.bone,
                         origin=origin)
 
 # Note that in the following, we explicitly pass in a subset of
 # the contour levels used for the filled contours.  Alternatively,
 # We could pass in additional levels to provide extra resolution,
 # or leave out the levels kwarg to use all of the original levels.
 
-CS2 = contour(CS, levels=CS.levels[::2],
+CS2 = plt.contour(CS, levels=CS.levels[::2],
                         colors = 'r',
                         origin=origin,
                         hold='on')
 
-title('Nonsense (3 masked regions)')
-xlabel('word length anomaly')
-ylabel('sentence length anomaly')
+plt.title('Nonsense (3 masked regions)')
+plt.xlabel('word length anomaly')
+plt.ylabel('sentence length anomaly')
 
 # Make a colorbar for the ContourSet returned by the contourf call.
-cbar = colorbar(CS)
+cbar = plt.colorbar(CS)
 cbar.ax.set_ylabel('verbosity coefficient')
 # Add the contour line levels to the colorbar
 cbar.add_lines(CS2)
 
-figure()
+plt.figure()
 
 # Now make a contour plot with the levels specified,
 # and with the colormap generated automatically from a list
 # of colors.
 levels = [-1.5, -1, -0.5, 0, 0.5, 1]
-CS3 = contourf(X, Y, Z, levels,
+CS3 = plt.contourf(X, Y, Z, levels,
                         colors = ('r', 'g', 'b'),
                         origin=origin,
                         extend='both')
@@ -72,16 +74,34 @@
 CS3.cmap.set_under('yellow')
 CS3.cmap.set_over('cyan')
 
-CS4 = contour(X, Y, Z, levels,
+CS4 = plt.contour(X, Y, Z, levels,
                        colors = ('k',),
                        linewidths = (3,),
                        origin = origin)
-title('Listed colors (3 masked regions)')
-clabel(CS4, fmt = '%2.1f', colors = 'w', fontsize=14)
+plt.title('Listed colors (3 masked regions)')
+plt.clabel(CS4, fmt = '%2.1f', colors = 'w', fontsize=14)
 
 # Notice that the colorbar command gets all the information it
 # needs from the ContourSet object, CS3.
-colorbar(CS3)
-
-show()
+plt.colorbar(CS3)
+
+# Illustrate all 4 possible "extend" settings:
+extends = ["neither", "both", "min", "max"]
+cmap = plt.cm.get_cmap("winter")
+cmap.set_under("magenta")
+cmap.set_over("yellow")
+# Note: contouring simply excludes masked or nan regions, so
+# instead of using the "bad" colormap value for them, it draws
+# nothing at all in them.  Therefore the following would have
+# no effect:
+#cmap.set_bad("red")
+
+fig, axs = plt.subplots(2,2)
+for ax, extend in zip(axs.ravel(), extends):
+    cs = ax.contourf(X, Y, Z, levels, cmap=cmap, extend=extend, origin=origin)
+    fig.colorbar(cs, ax=ax, shrink=0.9)
+    ax.set_title("extend = %s" % extend)
+    ax.locator_params(nbins=4)
+
+plt.show()