Fix hexbin raising ValueError on empty dataset

Umair Idris · Umair Idris · commit e864d94a2fbf · 2015-02-17T18:10:57.000-05:00
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -3846,10 +3846,9 @@ def hexbin(self, x, y, C=None, gridsize=100, bins=None,
         if extent is not None:
             xmin, xmax, ymin, ymax = extent
         else:
-            xmin = np.amin(x)
-            xmax = np.amax(x)
-            ymin = np.amin(y)
-            ymax = np.amax(y)
+            xmin, xmax  = (np.amin(x), np.amax(x)) if x else (0, 1) 
+            ymin, ymax = (np.amin(y), np.amax(y)) if y else (0, 1)  
+
             # to avoid issues with singular data, expand the min/max pairs
             xmin, xmax = mtrans.nonsingular(xmin, xmax, expander=0.1)
             ymin, ymax = mtrans.nonsingular(ymin, ymax, expander=0.1)
@@ -5606,8 +5605,6 @@ def hist(self, x, bins=10, range=None, normed=False, weights=None,
 
         # basic input validation
         flat = np.ravel(x)
-        if len(flat) == 0:
-            raise ValueError("x must have at least one data point")
 
         # Massage 'x' for processing.
         # NOTE: Be sure any changes here is also done below to 'weights'
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -482,6 +482,9 @@ def test_hexbin_extent():
 
     ax.hexbin(x, y, extent=[.1, .3, .6, .7])
 
+def test_hexbin_empty():
+    # From #3886: creating hexbin on empty dataset raises ValueError
+    ax.hexbin([], [])
 
 @cleanup
 def test_hexbin_pickable():
