Fastpaths for Timestamp properties (#18539)

Author: jbrockmendel

asv_bench/benchmarks/timestamp.py

@@ -1,4 +1,3 @@
-from .pandas_vb_common import *
 from pandas import to_timedelta, Timestamp
 import pytz
 import datetime
@@ -7,61 +6,64 @@
 class TimestampProperties(object):
     goal_time = 0.2
 
-    params = [None, pytz.timezone('Europe/Amsterdam')]
-    param_names = ['tz']
+    params = [(None, None),
+              (pytz.timezone('Europe/Amsterdam'), None),
+              (None, 'B'),
+              (pytz.timezone('Europe/Amsterdam'), 'B')]
+    param_names = ['tz', 'freq']
 
-    def setup(self, tz):
-        self.ts = Timestamp('2017-08-25 08:16:14', tzinfo=tz)
+    def setup(self, tz, freq):
+        self.ts = Timestamp('2017-08-25 08:16:14', tzinfo=tz, freq=freq)
 
-    def time_tz(self, tz):
+    def time_tz(self, tz, freq):
         self.ts.tz
 
-    def time_offset(self, tz):
+    def time_offset(self, tz, freq):
         self.ts.offset
 
-    def time_dayofweek(self, tz):
+    def time_dayofweek(self, tz, freq):
         self.ts.dayofweek
 
-    def time_weekday_name(self, tz):
+    def time_weekday_name(self, tz, freq):
         self.ts.weekday_name
 
-    def time_dayofyear(self, tz):
+    def time_dayofyear(self, tz, freq):
         self.ts.dayofyear
 
-    def time_week(self, tz):
+    def time_week(self, tz, freq):
         self.ts.week
 
-    def time_quarter(self, tz):
+    def time_quarter(self, tz, freq):
         self.ts.quarter
 
-    def time_days_in_month(self, tz):
+    def time_days_in_month(self, tz, freq):
         self.ts.days_in_month
 
-    def time_freqstr(self, tz):
+    def time_freqstr(self, tz, freq):
         self.ts.freqstr
 
-    def time_is_month_start(self, tz):
+    def time_is_month_start(self, tz, freq):
         self.ts.is_month_start
 
-    def time_is_month_end(self, tz):
+    def time_is_month_end(self, tz, freq):
         self.ts.is_month_end
 
-    def time_is_quarter_start(self, tz):
+    def time_is_quarter_start(self, tz, freq):
         self.ts.is_quarter_start
 
-    def time_is_quarter_end(self, tz):
+    def time_is_quarter_end(self, tz, freq):
         self.ts.is_quarter_end
 
-    def time_is_year_start(self, tz):
+    def time_is_year_start(self, tz, freq):
         self.ts.is_quarter_end
 
-    def time_is_year_end(self, tz):
+    def time_is_year_end(self, tz, freq):
         self.ts.is_quarter_end
 
-    def time_is_leap_year(self, tz):
+    def time_is_leap_year(self, tz, freq):
         self.ts.is_quarter_end
 
-    def time_microsecond(self, tz):
+    def time_microsecond(self, tz, freq):
         self.ts.microsecond
 
 

pandas/_libs/tslibs/timestamps.pyx

@@ -304,10 +304,12 @@ cdef class _Timestamp(datetime):
         out = get_date_field(np.array([val], dtype=np.int64), field)
         return int(out[0])
 
-    cpdef _get_start_end_field(self, field):
+    cpdef bint _get_start_end_field(self, str field):
         cdef:
             int64_t val
             dict kwds
+            ndarray out
+            int month_kw
 
         freq = self.freq
         if freq:
@@ -713,7 +715,7 @@ class Timestamp(_Timestamp):
 
     @property
     def quarter(self):
-        return self._get_field('q')
+        return ((self.month - 1) // 3) + 1
 
     @property
     def days_in_month(self):
@@ -727,26 +729,44 @@ class Timestamp(_Timestamp):
 
     @property
     def is_month_start(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return self.day == 1
         return self._get_start_end_field('is_month_start')
 
     @property
     def is_month_end(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return self.day == self.days_in_month
         return self._get_start_end_field('is_month_end')
 
     @property
     def is_quarter_start(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return self.day == 1 and self.month % 3 == 1
         return self._get_start_end_field('is_quarter_start')
 
     @property
     def is_quarter_end(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return (self.month % 3) == 0 and self.day == self.days_in_month
         return self._get_start_end_field('is_quarter_end')
 
     @property
     def is_year_start(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return self.day == self.month == 1
         return self._get_start_end_field('is_year_start')
 
     @property
     def is_year_end(self):
+        if self.freq is None:
+            # fast-path for non-business frequencies
+            return self.month == 12 and self.day == 31
         return self._get_start_end_field('is_year_end')
 
     @property

pandas/tests/scalar/test_timestamp.py

@@ -47,6 +47,28 @@ def test_overflow_offset(self):
             stamp - offset
 
 
+class TestTimestampProperties(object):
+
+    def test_properties_business(self):
+        ts = Timestamp('2017-10-01', freq='B')
+        control = Timestamp('2017-10-01')
+        assert ts.dayofweek == 6
+        assert not ts.is_month_start    # not a weekday
+        assert not ts.is_quarter_start  # not a weekday
+        # Control case: non-business is month/qtr start
+        assert control.is_month_start
+        assert control.is_quarter_start
+
+        ts = Timestamp('2017-09-30', freq='B')
+        control = Timestamp('2017-09-30')
+        assert ts.dayofweek == 5
+        assert not ts.is_month_end    # not a weekday
+        assert not ts.is_quarter_end  # not a weekday
+        # Control case: non-business is month/qtr start
+        assert control.is_month_end
+        assert control.is_quarter_end
+
+
 class TestTimestamp(object):
 
     def test_constructor(self):