Merge pull request #15017 from meeseeksmachine/auto-backport-of-pr-15007-on-v3.1.x

jklymak · web-flow · commit 4622afdda60b · 2019-08-09T10:36:34.000-07:00
Backport PR #15007 on branch v3.1.x (FIX: support pandas 0.25)
diff --git a/lib/matplotlib/cbook/__init__.py b/lib/matplotlib/cbook/__init__.py
@@ -1399,7 +1399,13 @@ def _check_1d(x):
         return np.atleast_1d(x)
     else:
         try:
-            x[:, None]
+            ndim = x[:, None].ndim
+            # work around https://github.com/pandas-dev/pandas/issues/27775
+            # which mean the shape is not as expected. That this ever worked
+            # was an unintentional quirk of pandas the above line will raise
+            # an exception in the future.
+            if ndim < 2:
+                return np.atleast_1d(x)
             return x
         except (IndexError, TypeError):
             return np.atleast_1d(x)
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -5522,6 +5522,12 @@ def test_pandas_errorbar_indexing(pd):
     ax.errorbar('x', 'y', xerr='xe', yerr='ye', data=df)
 
 
+def test_pandas_index_shape(pd):
+    df = pd.DataFrame({"XX": [4, 5, 6], "YY": [7, 1, 2]})
+    fig, ax = plt.subplots()
+    ax.plot(df.index, df['YY'])
+
+
 def test_pandas_indexing_hist(pd):
     ser_1 = pd.Series(data=[1, 2, 2, 3, 3, 4, 4, 4, 4, 5])
     ser_2 = ser_1.iloc[1:]
