Merge branch 'use-base-in-resample' of https://github.com/captainsafia/pandas into captainsafia-use-base-in-resample

Author: jreback

pandas/tests/test_tseries.py

@@ -423,7 +423,6 @@ def test_series_bin_grouper():
     exp_counts = np.array([3, 3, 4], dtype=np.int64)
     assert_almost_equal(counts, exp_counts)
 
-
 class TestBinGroupers(tm.TestCase):
     _multiprocess_can_split_ = True
 

pandas/tseries/resample.py

@@ -68,7 +68,6 @@ def __init__(self, freq='Min', closed=None, label=None, how='mean',
         self.fill_method = fill_method
         self.limit = limit
         self.base = base
-
         # always sort time groupers
         kwargs['sort'] = True
 
@@ -229,13 +228,22 @@ def _get_time_delta_bins(self, ax):
         if not len(ax):
             binner = labels = TimedeltaIndex(data=[], freq=self.freq, name=ax.name)
             return binner, [], labels
-
+        
         labels = binner = TimedeltaIndex(start=ax[0],
                                          end=ax[-1],
                                          freq=self.freq,
                                          name=ax.name)
 
         end_stamps = labels + 1
+
+        # Addresses GH #10530
+        if self.base > 0:
+            last = labels[-1]
+            labels_shifted = labels.copy()
+            labels_shifted = labels_shifted.shift(self.base)
+            labels_shifted = labels_shifted[labels_shifted <= last]
+            labels = labels_shifted
+
         bins = ax.searchsorted(end_stamps, side='left')
 
         return binner, bins, labels
@@ -274,6 +282,7 @@ def _resample_timestamps(self, kind=None):
         binner = self.binner
         obj = self.obj
 
+
         # Determine if we're downsampling
         if axlabels.freq is not None or axlabels.inferred_freq is not None:
 

pandas/tseries/tests/test_resample.py

@@ -11,6 +11,7 @@
 
 from pandas.core.groupby import DataError
 from pandas.tseries.index import date_range
+from pandas.tseries.tdi import timedelta_range
 from pandas.tseries.offsets import Minute, BDay
 from pandas.tseries.period import period_range, PeriodIndex, Period
 from pandas.tseries.resample import DatetimeIndex, TimeGrouper
@@ -625,8 +626,23 @@ def test_resample_base(self):
         resampled = ts.resample('5min', base=2)
         exp_rng = date_range('12/31/1999 23:57:00', '1/1/2000 01:57',
                              freq='5min')
+
         self.assertTrue(resampled.index.equals(exp_rng))
 
+    def test_resample_base_with_timedeltaindex(self):
+        rng = timedelta_range(start = '0s', periods = 25, freq = 's')
+        ts = Series(np.random.randn(len(rng)), index = rng)
+        
+        with_base = ts.resample('2s', base = 5)
+        without_base = ts.resample('2s')
+
+        exp_without_base = timedelta_range(start = '0s', end = '25s', freq = '2s')
+        exp_with_base = timedelta_range(start = '10s', end = '25s', freq = '2s')
+
+        self.assertTrue(without_base.index.equals(exp_without_base))
+        self.assertTrue(with_base.index.equals(exp_with_base))
+
+
     def test_resample_daily_anchored(self):
         rng = date_range('1/1/2000 0:00:00', periods=10000, freq='T')
         ts = Series(np.random.randn(len(rng)), index=rng)