CF Checker

The CF Checker is a utility that checks the contents of a NetCDF file complies with the Climate and Forecasts (CF) Metadata Convention.

Dependencies

• The package runs on Linux and Mac OS operating systems.

• Python 3.x

• netcdf4-python at version 1.2.5 or newer. This package requires netCDF, HDF5 and zlib libraries.

• cfunits-python package version 3.0.0 or newer

• numpy version 1.15 or newer

Installation

To install from PyPI:

pip install cfchecker

To install from Conda-forge:

conda create -n cfchecker -c conda-forge cfchecker # create new env OR
conda install cfchecker -c conda-forge             # install on existing env

Alternatively, to install from source:

1. Download the cfchecker package from cfchecker releases

2. Unpack the library:

   tar -zxf cfchecker-${version}.tar.gz
   
   cd cfchecker-${version}

3. Install the package:

   • To install to a central location:

     python setup.py install

   • To install to a non standard location:

     python setup.py install --prefix=<directory>

     If directory you are installing into is not on PYTHONPATH you will need to add it.

Running the CF Checker

cfchecks [-a <area-types.xml>] [-r <regions.xml>] [-s <std_names.xml>] [-v <CFVersion>] [-x] [-t <cache_time_days>] file1 [file2...]

For further details and for other available command line options please see the help by running cfchecks -h

Environment Variables

The following parameters can be set on the command-line or through environment variables:

1. CF_STANDARD_NAMES or (CL option -s) : The path or URL to the CF standard names table
2. CF_AREA_TYPES or (CL option -a) : The path or URL to the CF area types table
3. CF_REGION_NAMES or (CL option -r): The path or URL to the CF region names table

Running the Test script

In the release tarball there is a test_files directory containing a test.sh script which runs a series of test files through the CF Checker and confirms the checker is working as expected. It is a very elementary system, which will be rewritten soon. Before running it you will need to edit the location of the cfchecks script in the tests.sh file:

cfchecker="<location of cfchecks>"

Then just run the tests.sh script:

./tests.sh