Add example script making a Joy Divsion plot

examples/kde_joyplot.py

@@ -0,0 +1,44 @@
+"""
+Overlapping KDEs ('Joy Division plot')
+======================================
+
+
+"""
+import numpy as np
+import pandas as pd
+import seaborn as sns
+import matplotlib.pyplot as plt
+sns.set(style="white", rc={"axes.facecolor": (0, 0, 0, 0)})
+
+# Create the data
+rs = np.random.RandomState(1979)
+x = rs.randn(500)
+g = np.tile(list("ABCDEFGHIJ"), 50)
+df = pd.DataFrame(dict(x=x, g=g))
+m = df.g.map(ord)
+df["x"] += m
+
+# Initialize the FacetGrid object
+pal = sns.cubehelix_palette(10, rot=-.25, light=.7)
+g = sns.FacetGrid(df, row="g", hue="g", aspect=12, size=.5, palette=pal)
+
+# Draw the densities in a few steps
+g.map(sns.kdeplot, "x", clip_on=False, shade=True, alpha=1, lw=1.5, bw=.2)
+g.map(sns.kdeplot, "x", clip_on=False, color="w", lw=2, bw=.2)
+g.map(plt.axhline, y=0, lw=2, clip_on=False)
+
+# Define and use a simple function to label the plot in axes coordinates
+def label(x, color, label):
+    ax = plt.gca()
+    ax.text(0, .2, label, fontweight="bold", color=color, 
+            ha="left", va="center", transform=ax.transAxes)
+
+g.map(label, "x")
+
+# Set the subplots to overlap
+g.fig.subplots_adjust(hspace=-.25)
+
+# Remove axes details that don't play will with overlap
+g.set_titles("")
+g.set(yticks=[])
+g.despine(bottom=True, left=True)

seaborn/distributions.py

@@ -298,19 +298,26 @@ def _univariate_kdeplot(data, shade, vertical, kernel, bw, gridsize, cut,
     label = "_nolegend_" if label is None else label
 
     # Use the active color cycle to find the plot color
+    facecolor = kwargs.pop("facecolor", None)
     line, = ax.plot(x, y, **kwargs)
     color = line.get_color()
     line.remove()
     kwargs.pop("color", None)
+    facecolor = color if facecolor is None else facecolor
 
     # Draw the KDE plot and, optionally, shade
     ax.plot(x, y, color=color, label=label, **kwargs)
-    alpha = kwargs.get("alpha", 0.25)
+    shade_kws = dict(
+        facecolor=facecolor,
+        alpha=kwargs.get("alpha", 0.25),
+        clip_on=kwargs.get("clip_on", True),
+        zorder=kwargs.get("zorder", 1),
+        )
     if shade:
         if vertical:
-            ax.fill_betweenx(y, 0, x, facecolor=color, alpha=alpha)
+            ax.fill_betweenx(y, 0, x, **shade_kws)
         else:
-            ax.fill_between(x, 0, y, facecolor=color, alpha=alpha)
+            ax.fill_between(x, 0, y, **shade_kws)
 
     # Set the density axis minimum to 0
     if vertical: