Tutorial

This tutorial assumes that you have downloaded the code and additional Netcdf validation files needed to run the tutorial and example calculations. These are available on Github.

The directory structure is assumed to be:

pytropd
| -- pytropd               <-- Run the tutorial from inside this directory
|    | -- tutorial.py
|    | -- functions.py
|    | -- __init__.py
|    | -- metrics.py
|    | -- TropD_Example_Calculations.py
| -- ValidationData
|    | -- *.nc             <-- Collection of netcdf data files used by
|    `                         tutorial.py and TropD_Example_Calculations.py
` -- ValidationMetrics
     | -- *.nc             <-- Collection of netcdf validation data files with
     `                         precomputed metrics used by TropD_Example_Calculations.py

First import pytropd and some data.

In [1]: import pytropd as pyt

In [2]: from pytropd.tutorial import lat, lev, V

In [3]: print V

V is a numpy array containing the mean meridional velocity on (lat, levs). We can calculate the metric of tropical width from the mass streamfunction (PSI) as follows:

In [4]: Phi_sh, Phi_nh = pyt.TropD_Metric_PSI(V[j,:,:], lat, lev)

In [5]: print(Phi_sh, Phi_nh)

More detailed code examples can be found in the file TropD_Example_Calculations.py.