Use LineCollection in stem

dstansby · dstansby · commit f2c2e54e95b3 · 2017-10-25T19:00:17.000+01:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -2505,12 +2505,12 @@ def stem(self, *args, **kwargs):
         if bottom is None:
             bottom = 0
 
-        stemlines = []
+        lines = []
         for thisx, thisy in zip(x, y):
-            l, = self.plot([thisx, thisx], [bottom, thisy],
-                           color=linecolor, linestyle=linestyle,
-                           marker=linemarker, label="_nolegend_")
-            stemlines.append(l)
+            lines.append(((thisx, bottom), (thisx, thisy)))
+        stemlines = mcoll.LineCollection(lines, linestyles=linestyle,
+                                         colors=linecolor, label='_nolegend_')
+        self.add_collection(stemlines)
 
         baseline, = self.plot([np.min(x), np.max(x)], [bottom, bottom],
                               color=basecolor, linestyle=basestyle,
