matplotlib · MC-Escherichia · Sep 27, 2014 · Sep 27, 2014 · Sep 27, 2014 · Sep 27, 2014
diff --git a/examples/pie_and_polar_charts/pie_demo_features.py b/examples/pie_and_polar_charts/pie_demo_features.py
@@ -19,15 +19,47 @@
 import matplotlib.pyplot as plt
 
 
+def pie_demo_features(ax, sizes, labels, colors, explode):
+    """
+    produces a simple pie plot on ax according to sizes, labels, colors and explode.
+
+    Parameters
+    ----------
+    ax :  PolarAxesSubplot
+          Axes on which to plot polar_bar
+
+    sizes : array
+            comparative sizes of pie slices
+
+    labels : array
+           names of pie slices
+
+    colors : array
+           colors of pie slices
+
+    explode : tuple
+           how far to explode each slice (0 for don't explode)
+
+    Returns
+    -------
+    pi : artist object returned
+
+         Returns artist for further modification.
+    """
+
+    pi = ax.pie(sizes, explode=explode, labels=labels, colors=colors,
+                autopct='%1.1f%%', shadow=True, startangle=90)
+    # Set aspect rtio to be equal so that pie is drawn as a circle.
+    ax.axis('equal')
+    return pi
+
+# Example data:
 # The slices will be ordered and plotted counter-clockwise.
 labels = 'Frogs', 'Hogs', 'Dogs', 'Logs'
 sizes = [15, 30, 45, 10]
 colors = ['yellowgreen', 'gold', 'lightskyblue', 'lightcoral']
-explode = (0, 0.1, 0, 0) # only "explode" the 2nd slice (i.e. 'Hogs')
-
-plt.pie(sizes, explode=explode, labels=labels, colors=colors,
-        autopct='%1.1f%%', shadow=True, startangle=90)
-# Set aspect ratio to be equal so that pie is drawn as a circle.
-plt.axis('equal')
+explode = (0, 0.1, 0, 0)  # only "explode" the 2nd slice (i.e. 'Hogs')
+ax = plt.subplot(111)
 
+pie_demo_features(ax, sizes, labels, colors, explode)
 plt.show()
diff --git a/examples/pie_and_polar_charts/polar_bar_demo.py b/examples/pie_and_polar_charts/polar_bar_demo.py
@@ -5,17 +5,48 @@
 import matplotlib.pyplot as plt
 
 
-N = 20
-theta = np.linspace(0.0, 2 * np.pi, N, endpoint=False)
-radii = 10 * np.random.rand(N)
-width = np.pi / 4 * np.random.rand(N)
+def polar_bar_demo(ax, theta, radii, width):
+    """
+    produces a randomly colored polar plot given three arrays,
+    theta, radii,width .
 
-ax = plt.subplot(111, polar=True)
-bars = ax.bar(theta, radii, width=width, bottom=0.0)
+    Parameters
+    ----------
+    ax :  PolarAxesSubplot
+          Axes on which to plot polar_bar
+
+    theta : array
+            Angles at which to plot polar bars
+
+    radii : array
+            lengths of polar bar
+
+    width : array
+            widths of polars bars
+
+    Returns
+    -------
+    bars : artist object returned
+
+         Returns axes for further modification.
+    """
+
+    bars = ax.bar(theta, radii, width=width, bottom=0.0)
 
 # Use custom colors and opacity
-for r, bar in zip(radii, bars):
-    bar.set_facecolor(plt.cm.jet(r / 10.))
-    bar.set_alpha(0.5)
+    for r, bar in zip(radii, bars):
+        bar.set_facecolor(plt.cm.jet(r / 10.))
+        bar.set_alpha(0.5)
+
+    return bars
+
+# Generate Example Data.
+N = 20
+ex_theta = np.linspace(0.0, 2 * np.pi, N, endpoint=False)
+ex_radii = 10 * np.random.rand(N)
+ex_width = np.pi / 4 * np.random.rand(N)
+
+ax = plt.subplot(111, polar=True)
+polar_bar_demo(ax, ex_theta, ex_radii, ex_width)
 
 plt.show()
diff --git a/examples/pie_and_polar_charts/polar_scatter_demo.py b/examples/pie_and_polar_charts/polar_scatter_demo.py
@@ -8,14 +8,47 @@
 import matplotlib.pyplot as plt
 
 
+def polar_scatter_demo(ax, theta, r, area, colors):
+    """
+    produces a randomly colored polar plot given three arrays,
+    theta, radii,width .
+
+    Parameters
+    ----------
+    ax :  PolarAxesSubplot
+          Axes on which to plot polar_scatter
+
+    theta : array
+            Angles at which to plot points
+
+    r : array
+            radii at which to plot points
+
+    area : array
+           sizes of points
+
+    colors : array
+           color values of points.
+
+    Returns
+    -------
+    c : artist object returned
+
+    """
+    c = ax.scatter(theta, r, c=colors, s=area, cmap=plt.cm.hsv)
+    c.set_alpha(0.75)
+    return c
+
+
+# example data
 N = 150
-r = 2 * np.random.rand(N)
-theta = 2 * np.pi * np.random.rand(N)
-area = 200 * r**2 * np.random.rand(N)
-colors = theta
+ex_r = 2 * np.random.rand(N)
+ex_theta = 2 * np.pi * np.random.rand(N)
+ex_area = 200 * r ** 2 * np.random.rand(N)
+ex_colors = theta
 
 ax = plt.subplot(111, polar=True)
-c = plt.scatter(theta, r, c=colors, s=area, cmap=plt.cm.hsv)
-c.set_alpha(0.75)
+
+polar_scatter_demo(ax, ex_theta, ex_r, ex_area, ex_colors)
 
 plt.show()
diff --git a/examples/specialty_plots/hinton_demo.py b/examples/specialty_plots/hinton_demo.py
@@ -12,19 +12,18 @@
 import matplotlib.pyplot as plt
 
 
-def hinton(matrix, max_weight=None, ax=None):
+def hinton(ax, matrix, max_weight=None):
     """Draw Hinton diagram for visualizing a weight matrix."""
-    ax = ax if ax is not None else plt.gca()
 
     if not max_weight:
-        max_weight = 2**np.ceil(np.log(np.abs(matrix).max())/np.log(2))
+        max_weight = 2 ** np.ceil(np.log(np.abs(matrix).max()) / np.log(2))
 
     ax.patch.set_facecolor('gray')
     ax.set_aspect('equal', 'box')
     ax.xaxis.set_major_locator(plt.NullLocator())
     ax.yaxis.set_major_locator(plt.NullLocator())
 
-    for (x,y),w in np.ndenumerate(matrix):
+    for (x, y), w in np.ndenumerate(matrix):
         color = 'white' if w > 0 else 'black'
         size = np.sqrt(np.abs(w))
         rect = plt.Rectangle([x - size / 2, y - size / 2], size, size,
@@ -33,8 +32,11 @@ def hinton(matrix, max_weight=None, ax=None):
 
     ax.autoscale_view()
     ax.invert_yaxis()
+    return ax
 
+ax = plt.subplot(111)
 
-if __name__ == '__main__':
-    hinton(np.random.rand(20, 20) - 0.5)
-    plt.show()
+
+hinton(ax, np.random.rand(20, 20) - 0.5)
+
+plt.show()