##############################
Map Projection (using Cartopy)
##############################

This page introduces a program that plots monthly temperature at each station on a map.

Monthly dataset
---------------

If data has a higher time resolution than the monthly average, you need to calculate the monthly average.
 
.. literalinclude:: programs/maps.temp.py
   :language: python
   :lines: 61-62

Monthly temperature plots on a map
----------------------------------

Cartopy install
===============
The map projection uses `cartopy <https://scitools.org.uk/cartopy/docs/latest/>`__ package. 

The information on cartopy installation is available `here <https://scitools.org.uk/cartopy/docs/latest/installing.html#installing>`__.

You can simply command ``$ conda install -n env_weclim -c conda-forge cartopy``.

Map plots
=========

The background map can be drawn using the following commends:

.. literalinclude:: programs/maps.temp.py
   :language: python
   :lines: 15-16, 93-101

The monthly temperature can be plots at each location using ``pandas.DataFrame.plot`` command (`command information <https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.plot.html>`__).

.. literalinclude:: programs/maps.temp.py
   :language: python
   :lines: 104-118

Sample program for maps
========================

Source file: :download:`maps.temp.py <programs/maps.temp.py>`

Create animation
----------------

PNG files can be converted to animated images (gif file).

.. literalinclude:: programs/animate.txt
   :lines: 1

Here, ``-delay N`` is the frame rate of N/100 (seconds) and  ``-loop M`` is the number of loop of the animation image.

You can check the animation image as ``$ animate XX.gif``.

Gallery
-------

Monthly temperature at each weather station (oC).

.. image:: SRC/TAIR.gif
  :height: 300