BUG: axis kw not propogating on pct_change #11150

Author: Tux1

doc/source/whatsnew/v0.17.1.txt

@@ -44,6 +44,7 @@ API changes
   Legacy Python syntax (``set([x, y])``) (:issue:`11215`)
 - Indexing with a null key will raise a ``TypeError``, instead of a ``ValueError`` (:issue:`11356`)
 - ``Series.sort_index()`` now correctly handles the ``inplace`` option (:issue:`11402`)
+
 - ``DataFrame.itertuples()`` now returns ``namedtuple`` objects, when possible. (:issue:`11269`)
 
 .. _whatsnew_0171.deprecations:
@@ -83,6 +84,7 @@ Bug Fixes
 - Bug in ``HDFStore.append`` with strings whose encoded length exceded the max unencoded length (:issue:`11234`)
 - Bug in merging ``datetime64[ns, tz]`` dtypes (:issue:`11405`)
 - Bug in ``HDFStore.select`` when comparing with a numpy scalar in a where clause (:issue:`11283`)
+
 - Bug in using ``DataFrame.ix`` with a multi-index indexer(:issue:`11372`)
 
 
@@ -107,7 +109,7 @@ Bug Fixes
 
 
 
-
+- Bug in ``DataFrame.pct_change()`` not propagating ``axis`` keyword on ``.fillna`` method (:issue:`11150`)
 
 
 
@@ -116,6 +118,7 @@ Bug Fixes
 
 
 
+
 - Bug in ``DataFrame.to_latex()`` produces an extra rule when ``header=False`` (:issue:`7124`)
 
 

pandas/core/generic.py

@@ -4567,7 +4567,7 @@ def pct_change(self, periods=1, fill_method='pad', limit=None, freq=None,
         if fill_method is None:
             data = self
         else:
-            data = self.fillna(method=fill_method, limit=limit)
+            data = self.fillna(method=fill_method, limit=limit, axis=axis)
 
         rs = (data.div(data.shift(periods=periods, freq=freq,
                                   axis=axis, **kwargs)) - 1)

pandas/tests/test_generic.py

@@ -1699,6 +1699,21 @@ def test_set_attribute(self):
         assert_equal(df.y, 5)
         assert_series_equal(df['y'], Series([2, 4, 6], name='y'))
 
+    def test_pct_change(self):
+        # GH 11150
+        pnl = DataFrame([np.arange(0, 40, 10), np.arange(0, 40, 10), np.arange(0, 40, 10)]).astype(np.float64)
+        pnl.iat[1,0] = np.nan
+        pnl.iat[1,1] = np.nan
+        pnl.iat[2,3] = 60
+
+        mask = pnl.isnull()
+
+        for axis in range(2):
+            expected = pnl.ffill(axis=axis)/pnl.ffill(axis=axis).shift(axis=axis) - 1
+            expected[mask] = np.nan
+            result = pnl.pct_change(axis=axis, fill_method='pad')
+
+            self.assert_frame_equal(result, expected)
 
 class TestPanel(tm.TestCase, Generic):
     _typ = Panel
@@ -1878,6 +1893,7 @@ def test_pipe_panel(self):
         with tm.assertRaises(ValueError):
             result = wp.pipe((f, 'y'), x=1, y=1)
 
+
 if __name__ == '__main__':
     nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],
                    exit=False)