Fix DataFrame.resample bug for empty DataFrame #2640

Author: changhiskhan

pandas/tseries/resample.py

@@ -94,6 +94,8 @@ def resample(self, obj):
             else:
                 obj = obj.to_timestamp(how=self.convention)
                 rs = self._resample_timestamps(obj)
+        elif len(axis) == 0:
+            return obj
         else:  # pragma: no cover
             raise TypeError('Only valid with DatetimeIndex or PeriodIndex')
 

pandas/tseries/tests/test_resample.py

@@ -442,6 +442,10 @@ def test_resample_empty(self):
         self.assert_(len(result) == 0)
         self.assert_(result.index.freqstr == 'A-DEC')
 
+        xp = DataFrame()
+        rs = xp.resample('A')
+        assert_frame_equal(xp, rs)
+
     def test_weekly_resample_buglet(self):
         # #1327
         rng = date_range('1/1/2000', freq='B', periods=20)