DOC: Add windows.rst

doc/source/reference/window.rst

@@ -10,8 +10,10 @@ Rolling objects are returned by ``.rolling`` calls: :func:`pandas.DataFrame.roll
 Expanding objects are returned by ``.expanding`` calls: :func:`pandas.DataFrame.expanding`, :func:`pandas.Series.expanding`, etc.
 ExponentialMovingWindow objects are returned by ``.ewm`` calls: :func:`pandas.DataFrame.ewm`, :func:`pandas.Series.ewm`, etc.
 
-Standard moving window functions
---------------------------------
+.. _api.functions_rolling:
+
+Rolling window functions
+------------------------
 .. currentmodule:: pandas.core.window.rolling
 
 .. autosummary::
@@ -33,15 +35,25 @@ Standard moving window functions
    Rolling.aggregate
    Rolling.quantile
    Rolling.sem
+
+.. _api.functions_window:
+
+Weighted window functions
+-------------------------
+.. currentmodule:: pandas.core.window.rolling
+
+.. autosummary::
+   :toctree: api/
+
    Window.mean
    Window.sum
    Window.var
    Window.std
 
 .. _api.functions_expanding:
 
-Standard expanding window functions
------------------------------------
+Expanding window functions
+--------------------------
 .. currentmodule:: pandas.core.window.expanding
 
 .. autosummary::
@@ -64,8 +76,10 @@ Standard expanding window functions
    Expanding.quantile
    Expanding.sem
 
-Exponentially-weighted moving window functions
-----------------------------------------------
+.. _api.functions_ewm:
+
+Exponentially-weighted window functions
+---------------------------------------
 .. currentmodule:: pandas.core.window.ewm
 
 .. autosummary::
@@ -77,6 +91,8 @@ Exponentially-weighted moving window functions
    ExponentialMovingWindow.corr
    ExponentialMovingWindow.cov
 
+.. _api.indexers_window:
+
 Window indexer
 --------------
 .. currentmodule:: pandas

doc/source/user_guide/basics.rst

@@ -538,8 +538,8 @@ standard deviation of 1), very concisely:
 
 Note that methods like :meth:`~DataFrame.cumsum` and :meth:`~DataFrame.cumprod`
 preserve the location of ``NaN`` values. This is somewhat different from
-:meth:`~DataFrame.expanding` and :meth:`~DataFrame.rolling`.
-For more details please see :ref:`this note <stats.moments.expanding.note>`.
+:meth:`~DataFrame.expanding` and :meth:`~DataFrame.rolling` since ``NaN`` behavior
+is furthermore dictated by a ``min_periods`` parameter.
 
 .. ipython:: python
 
@@ -945,7 +945,7 @@ Aggregation API
 
 The aggregation API allows one to express possibly multiple aggregation operations in a single concise way.
 This API is similar across pandas objects, see :ref:`groupby API <groupby.aggregate>`, the
-:ref:`window functions API <stats.aggregate>`, and the :ref:`resample API <timeseries.aggregate>`.
+:ref:`window API <window.overview>`, and the :ref:`resample API <timeseries.aggregate>`.
 The entry point for aggregation is :meth:`DataFrame.aggregate`, or the alias
 :meth:`DataFrame.agg`.