ENH: finished fixing resampling period-indexed data, only 50% slower …

…than timestamps now, close pandas-dev#1152

pandas/core/groupby.py

@@ -371,7 +371,7 @@ def _cython_agg_general(self, how):
             if not issubclass(obj.dtype.type, (np.number, np.bool_)):
                 continue
 
-            result, names = self.grouper.aggregate(obj, how)
+            result, names = self.grouper.aggregate(obj.values, how)
             output[name] = result
 
         if len(output) == 0:

pandas/tseries/period.py

@@ -607,6 +607,8 @@ def freqstr(self):
     def asfreq(self, freq=None, how='E'):
         how = _validate_end_alias(how)
 
+        freq = _freq_mod.get_standard_freq(freq)
+
         base1, mult1 = _gfc(self.freq)
 
         if isinstance(freq, basestring):
@@ -621,7 +623,10 @@ def asfreq(self, freq=None, how='E'):
         new_data = lib.period_asfreq_arr(self.values, base1, mult1,
                                          base2, mult2, end)
 
-        return PeriodIndex(new_data, freq=freq)
+        result = new_data.view(PeriodIndex)
+        result.name = self.name
+        result.freq = freq
+        return result
 
     year = _field_accessor('year')
     month = _field_accessor('month')

vb_suite/timeseries.py

@@ -102,7 +102,7 @@
 ts = Series(np.random.randn(len(rng)), index=rng)
 """
 
-timeseries_period_resample_mean = \
+timeseries_period_downsample_mean = \
     Benchmark("ts.resample('D', how='mean')", setup,
               start_date=datetime(2012, 4, 25))
 
@@ -111,6 +111,6 @@
 ts = Series(np.random.randn(len(rng)), index=rng)
 """
 
-timeseries_timestamp_resample_mean = \
+timeseries_timestamp_downsample_mean = \
     Benchmark("ts.resample('D', how='mean')", setup,
               start_date=datetime(2012, 4, 25))