.. _quick_start:


Quick Start
===========


.. image:: https://dev.azure.com/MPAS-Dev/pyremap%20testing/_apis/build/status/MPAS-Dev.pyremap?branchName=main
   :target: https://dev.azure.com/MPAS-Dev/pyremap%20testing/_build/latest?definitionId=1&branchName=main
   :alt: Build Status


Python remapping tools for climate and earth system models.

Installation
------------

To use the latest version for developers, get the code from:
`https://github.com/MPAS-Dev/pyremap <https://github.com/MPAS-Dev/pyremap>`_

Then, you will need to set up a conda environment and install the package
in a way that points to the repo (so changes you make are available in the
conda environment):

.. code-block::

   conda config --add channels conda-forge
   conda config --set channel_priority strict
   conda create -y -n pyremap --file dev-spec.txt
   conda activate pyremap
   python -m pip install -e .

Examples
--------

.. code-block::

   cd examples

First, make mapping files for a lat-lon grid, and test it out by remapping
temperature from the example file:

.. code-block::

   wget https://web.lcrc.anl.gov/public/e3sm/inputdata/ocn/mpas-o/oQU240/ocean.QU.240km.151209.nc
   ./make_mpas_to_lat_lon_mapping.py

You should now see the mapping file:

.. code-block::

   map_oQU240_to_0.5x0.5degree.nc

as well as the input file (an initial condition for the MPAS-Ocean model) and
an example of temperature from the initial condition remapped to the new grid.

.. code-block::

   ocean.QU.240km.151209.nc
   temp_0.5x0.5degree.nc

Second, let's try the same but to an Antarctic stereographic grid:

.. code-block::

   ./make_mpas_to_Antarctic_stereo_mapping.py

Now, there's a new mapping file and example output file:

.. code-block::

   map_oQU240_to_6000.0x6000.0km_10.0km_Antarctic_stereo.nc
   temp_6000.0x6000.0km_10.0km_Antarctic_stereo.nc

Finally, let's remap the temperature on the Antarctic grid to a lower
resolution Antarctic grid:

.. code-block::

   ./remap_stereographic.py -i temp_6000.0x6000.0km_10.0km_Antarctic_stereo.nc \
       -o temp_6000.0x6000.0km_20.0km_Antarctic_stereo.nc -r 20

This created another mapping file and an output file:

.. code-block::

   map_6000x6000km_10km_Antarctic_stereo_to_6000x6000km_20.0km_Antarctic_stereo.nc
   temp_6000.0x6000.0km_20.0km_Antarctic_stereo.nc