Add 'name' as argument for index 'to_frame' method

pandas/core/indexes/base.py

@@ -1116,7 +1116,7 @@ def to_series(self, index=None, name=None):
 
         return Series(self._to_embed(), index=index, name=name)
 
-    def to_frame(self, index=True):
+    def to_frame(self, index=True, name=None):
         """
         Create a DataFrame with a column containing the Index.
 
@@ -1127,6 +1127,10 @@ def to_frame(self, index=True):
         index : boolean, default True
             Set the index of the returned DataFrame as the original Index.
 
+        name : object, default None
+            The passed name should substitute for the series name (if it has
+            one).
+
         Returns
         -------
         DataFrame
@@ -1154,10 +1158,17 @@ def to_frame(self, index=True):
         0   Ant
         1  Bear
         2   Cow
+
+        >>> idx.to_frame(index=False, name='zoo')
+            zoo
+        0   Ant
+        1  Bear
+        2   Cow
         """
 
         from pandas import DataFrame
-        name = self.name or 0
+        if name is None:
+            name = self.name or 0
         result = DataFrame({name: self.values.copy()})
 
         if index:

pandas/core/indexes/multi.py

@@ -1126,7 +1126,7 @@ def _to_safe_for_reshape(self):
         """ convert to object if we are a categorical """
         return self.set_levels([i._to_safe_for_reshape() for i in self.levels])
 
-    def to_frame(self, index=True):
+    def to_frame(self, index=True, names=None):
         """
         Create a DataFrame with the levels of the MultiIndex as columns.
 
@@ -1143,11 +1143,21 @@ def to_frame(self, index=True):
         """
 
         from pandas import DataFrame
-        result = DataFrame({(name or level):
-                            self._get_level_values(level)
-                            for name, level in
-                            zip(self.names, range(len(self.levels)))},
-                           copy=False)
+        if names is not None:
+            if len(names) != len(self.levels):
+                raise AssertionError("'names' should have same lenght as "
+                                     "number of levels on index")
+            result = DataFrame({(name):
+                                self._get_level_values(level)
+                                for name, level in
+                                zip(names, range(len(self.levels)))},
+                               copy=False)
+        else:
+            result = DataFrame({(name or level):
+                                self._get_level_values(level)
+                                for name, level in
+                                zip(self.names, range(len(self.levels)))},
+                               copy=False)
         if index:
             result.index = self
         return result

pandas/tests/indexes/common.py

@@ -81,6 +81,17 @@ def test_to_frame(self):
         df = idx.to_frame(index=False)
         assert df.index is not idx
 
+        new_idx_name = 'new_name'
+        df = idx.to_frame(name=new_idx_name)
+
+        assert df.index is idx
+        assert len(df.columns) == 1
+        assert df.columns[0] == new_idx_name
+        assert df[new_idx_name].values is not idx.values
+
+        df = idx.to_frame(index=False, name=new_idx_name)
+        assert df.index is not idx
+
     def test_shift(self):
 
         # GH8083 test the base class for shift

pandas/tests/indexes/multi/test_conversion.py

@@ -37,6 +37,17 @@ def test_to_frame():
     expected.index = index
     tm.assert_frame_equal(result, expected)
 
+    index = MultiIndex.from_tuples(tuples)
+    result = index.to_frame(index=False, names=['first', 'second'])
+    expected = DataFrame(tuples)
+    expected.columns = ['first', 'second']
+    tm.assert_frame_equal(result, expected)
+
+    result = index.to_frame(names=['first', 'second'])
+    expected.index = index
+    expected.columns = ['first', 'second']
+    tm.assert_frame_equal(result, expected)
+
     index = MultiIndex.from_product([range(5),
                                      pd.date_range('20130101', periods=3)])
     result = index.to_frame(index=False)
@@ -45,12 +56,20 @@ def test_to_frame():
             1: np.tile(pd.date_range('20130101', periods=3), 5)})
     tm.assert_frame_equal(result, expected)
 
-    index = MultiIndex.from_product([range(5),
-                                     pd.date_range('20130101', periods=3)])
     result = index.to_frame()
     expected.index = index
     tm.assert_frame_equal(result, expected)
 
+    result = index.to_frame(index=False, names=['first', 'second'])
+    expected = DataFrame(
+        {'first': np.repeat(np.arange(5, dtype='int64'), 3),
+         'second': np.tile(pd.date_range('20130101', periods=3), 5)})
+    tm.assert_frame_equal(result, expected)
+
+    result = index.to_frame(names=['first', 'second'])
+    expected.index = index
+    tm.assert_frame_equal(result, expected)
+
 
 def test_to_hierarchical():
     index = MultiIndex.from_tuples([(1, 'one'), (1, 'two'), (2, 'one'), (