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)