Series methods isnull and notnull

pandas/core/series.py

@@ -1603,7 +1603,7 @@ def to_csv(self, path):
         path : string or None
             Output filepath. If None, write to stdout
         """
-        f = open(path, 'wb')
+        f = open(path, 'w')
         csvout = csv.writer(f)
         csvout.writerows(self.iteritems())
         f.close()
@@ -1619,6 +1619,9 @@ def dropna(self):
         return remove_na(self)
 
     valid = dropna
+    
+    isnull = isnull
+    notnull = notnull
 
     def first_valid_index(self):
         """

pandas/tests/test_series.py

@@ -824,6 +824,18 @@ def test_valid(self):
         self.assertEqual(len(result), ts.count())
 
         common.assert_dict_equal(result, ts, compare_keys=False)
+    
+    def test_isnull(self):
+        ser = Series([0,5.4,3,nan,-0.001])
+        assert_series_equal(ser.isnull(), Series([False,False,False,True,False]))
+        ser = Series(["hi","",nan])
+        assert_series_equal(ser.isnull(), Series([False,False,True]))
+    
+    def test_notnull(self):
+        ser = Series([0,5.4,3,nan,-0.001])
+        assert_series_equal(ser.notnull(), Series([True,True,True,False,True]))
+        ser = Series(["hi","",nan])
+        assert_series_equal(ser.notnull(), Series([True,True,False]))
 
     def test_shift(self):
         shifted = self.ts.shift(1)

setup.py

@@ -113,6 +113,8 @@
     'Operating System :: OS Independent',
     'Intended Audience :: Science/Research',
     'Programming Language :: Python',
+    'Programming Language :: Python :: 2',
+    'Programming Language :: Python :: 3',
     'Programming Language :: Cython',
     'Topic :: Scientific/Engineering',
 ]