The cartopy module

The top level cartopy module contains the config dictionary which controls various aspects of cartopy’s behaviour.

cartopy.config

The config dictionary stores global configuration values for cartopy.

In the first instance, the config is defined in cartopy/__init__.py. It is possible to provide site wide customisations by including a siteconfig.py file along with the cartopy source code. siteconfig.py should contain a function called update_config which takes the config dictionary instance as its first and only argument (from where it is possible to update the dictionary howsoever desired).

For users without write permission to the cartopy source directory, a package called cartopy_userconfig should be made importable (consider putting it in site.getusersitepackages()) and should expose a function called update_config which takes the config dictionary as its first and only argument.

Keys in the config dictionary:

pre_existing_data_dir

The absolute path to a directory where standard data (such as that from NaturalEarth) can be found. If it is not found in this location the data_dir config item will be used.

data_dir

The absolute path to a directory where standard data (such as that from NaturalEarth) can be found. If it is not found and the item is downloadable cartopy will download the appropriate file(s) to a subdirectory of this directory, therefore data_dir should be writable by the user.

repo_data_dir

The absolute path to the directory where the data delivered with the cartopy repository is stored. Typically this will only be set by OS packagers and system administrators for site wide deployments.

downloaders

A dictionary mapping standard “specifications” to the appropriate Downloader. For further documentation and an example see cartopy.io.Downloader.from_config().