fix for issue #169

Changelog

@@ -1,6 +1,8 @@
 since version 1.1.2 release
 ===========================
  * add isoformat method for compatibility with python datetime(issue #152).
+ * make 'proleptic_gregorian' default calendar for cftime.datetime
+   so that dayofwk,dayofyr methods don't fail (issue #169).
 
 version 1.1.2 (release tag v1.1.2rel)
 =====================================

cftime/_cftime.pyx

@@ -1254,7 +1254,7 @@ Gregorial calendar.
 
     def __init__(self, int year, int month, int day, int hour=0, int minute=0,
                        int second=0, int microsecond=0, int dayofwk=-1, 
-                       int dayofyr = -1):
+                       int dayofyr = -1, calendar='proleptic_gregorian'):
 
         self.year = year
         self.month = month
@@ -1263,7 +1263,7 @@ Gregorial calendar.
         self.minute = minute
         self.second = second
         self.microsecond = microsecond
-        self.calendar = ""
+        self.calendar = calendar
         self.datetime_compatible = True
         self._dayofwk = dayofwk
         self._dayofyr = dayofyr

test/test_cftime.py

@@ -754,6 +754,10 @@ def test_tz_naive(self):
         # issue #165: make sure python datetime returned
         d=num2date(0,units="seconds since 2000-01-01 00:00:00",only_use_cftime_datetimes=False)
         assert isinstance(d, datetime)
+        # issue #169: cftime.datetime has no calendar attribute, causing dayofwk,dayofyr methods
+        # to fail.
+        c = cftime.datetime(*cftime._parse_date('7480-01-01 00:00:00'))
+        assert(c.strftime() == '7480-01-01 00:00:00')
 
 class TestDate2index(unittest.TestCase):