Added functionalities to docs main page

docs/index.rst

@@ -13,9 +13,11 @@ like `SWAN <http://swanmodel.sourceforge.net>`_, `Waverider buoys
 <http://datawell.nl>`_ and `WaveDroid <http://www.wavedroid.net>`_.
 
 Oceanwaves is based on the `xarray DataSet object
-<https://pypi.python.org/pypi/xarray>`_. Many of its functionalities
-are obtained from the `pyswan <https://github.com/openearth/pyswan>`_
-toolbox, originally developed by Gerben de Boer, and the `swantools
+<https://pypi.python.org/pypi/xarray>`_, but defines special variables
+for time, location, frequency and direction. Many of its
+functionalities are obtained from the `pyswan
+<https://github.com/openearth/pyswan>`_ toolbox, originally developed
+by Gerben de Boer, and the `swantools
 <https://pypi.python.org/pypi/swantools/>`_ toolbox, originally
 developed by Caio Eadi Stringari.
 
@@ -25,6 +27,41 @@ The source code of the oceanwaves package can be found at
 Usage examples can be found in this notebook
 `<https://github.com/openearth/oceanwaves-python/blob/master/notebooks/oceanwaves.ipynb>`_.
 
+The OceanWaves object supports various standard conversions, like:
+
+* From significant wave height to spectral
+* From omnidirectional to directional
+* From directional to omnidirectional
+* From spectral to significant wave height
+* From spectral to spectral wave period
+* From spectral to peak wave period
+* From directional to peak wave direction
+* From degrees to radians
+
+The OceanWaves object supports various standard plotting methods, like:
+
+* Polar subplots for directional data on multiple locations/times
+* Polar subplots on a map
+* Plots supported by `xarray.Dataset
+  <http://xarray.pydata.org/en/stable/generated/xarray.Dataset.html>`_
+  and `Seaborn <http://seaborn.pydata.org>`_
+
+The OceanWaves object can be instantiated from:
+
+* Raw data
+* SWaN 1D/2D spectral or table files
+* An `xarray.Dataset
+  <http://xarray.pydata.org/en/stable/generated/xarray.Dataset.html>`_
+  object
+* Another OceanWaves object
+
+The OceanWaves object can be written to:
+
+* SWaN 1D/2D spectral files
+* Output supported by `xarray.Dataset
+  <http://xarray.pydata.org/en/stable/generated/xarray.Dataset.html>`_
+  (e.g. netcdf)
+
 Contents:
 
 .. toctree::