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Author: TomAugspurger

doc/source/categorical.rst

@@ -152,9 +152,15 @@ This information can be stored in a :class:`~pandas.CategoricalDtype`.
 The ``categories`` argument is optional, which implies that the actual categories
 should be inferred from whatever is present in the data.
 
+.. ipython:: python
+
+   pd.CategoricalDtype(['a', 'b', 'c'])
+   pd.CategoricalDtype(['a', 'b', 'c'], ordered=True)
+   pd.CategoricalDtype()
+
 A :class:`~pandas.CategoricalDtype` can be used in any place pandas expects a
 `dtype`. For example :func:`pandas.read_csv`, :func:`pandas.DataFrame.astype`,
-the Series constructor, etc.
+or the Series constructor.
 
 As a convenience, you can use the string `'category'` in place of a
 :class:`pandas.CategoricalDtype` when you want the default behavior of
@@ -167,8 +173,9 @@ order of the ``categories`` is not considered
 .. ipython:: python
 
    c1 = pd.CategoricalDtype(['a', 'b', 'c'], ordered=False)
-   c2 = pd.CategoricalDtype(['b', 'c', 'a'], ordered=False)
-   c1 == c2
+   c1 == pd.CategoricalDtype(['b', 'c', 'a'], ordered=False)
+
+   c1 == pd.CategoricalDtype(['b',  'c', 'a'], ordered=True)
 
 Finally, all instances compare equal to the string `'category'`