Overview of the IPython configuration system

This section describes the IPython configuration system. This is based on traitlets.config; see that documentation for more information about the overall architecture.

Configuration file location

So where should you put your configuration files? IPython uses “profiles” for configuration, and by default, all profiles will be stored in the so called “IPython directory”. The location of this directory is determined by the following algorithm:

  • If the ipython-dir command line flag is given, its value is used.
  • If not, the value returned by IPython.paths.get_ipython_dir() is used. This function will first look at the IPYTHONDIR environment variable and then default to ~/.ipython. Historical support for the IPYTHON_DIR environment variable will be removed in a future release.

For most users, the configuration directory will be ~/.ipython.

Previous versions of IPython on Linux would use the XDG config directory, creating ~/.config/ipython by default. We have decided to go back to ~/.ipython for consistency among systems. IPython will issue a warning if it finds the XDG location, and will move it to the new location if there isn’t already a directory there.

Once the location of the IPython directory has been determined, you need to know which profile you are using. For users with a single configuration, this will simply be ‘default’, and will be located in <IPYTHONDIR>/profile_default.

The next thing you need to know is what to call your configuration file. The basic idea is that each application has its own default configuration filename. The default named used by the ipython command line program is ipython_config.py, and all IPython applications will use this file. Other applications, such as the parallel ipcluster scripts or the QtConsole will load their own config files after ipython_config.py. To load a particular configuration file instead of the default, the name can be overridden by the config_file command line flag.

To generate the default configuration files, do:

$ ipython profile create

and you will have a default ipython_config.py in your IPython directory under profile_default. If you want the default config files for the IPython.parallel applications, add --parallel to the end of the command-line args.

Locating these files

From the command-line, you can quickly locate the IPYTHONDIR or a specific profile with:

$ ipython locate
/home/you/.ipython

$ ipython locate profile foo
/home/you/.ipython/profile_foo

These map to the utility functions: IPython.utils.path.get_ipython_dir() and IPython.utils.path.locate_profile() respectively.

Profiles

A profile is a directory containing configuration and runtime files, such as logs, connection info for the parallel apps, and your IPython command history.

The idea is that users often want to maintain a set of configuration files for different purposes: one for doing numerical computing with NumPy and SciPy and another for doing symbolic computing with SymPy. Profiles make it easy to keep a separate configuration files, logs, and histories for each of these purposes.

Let’s start by showing how a profile is used:

$ ipython --profile=sympy

This tells the ipython command line program to get its configuration from the “sympy” profile. The file names for various profiles do not change. The only difference is that profiles are named in a special way. In the case above, the “sympy” profile means looking for ipython_config.py in <IPYTHONDIR>/profile_sympy.

The general pattern is this: simply create a new profile with:

$ ipython profile create <name>

which adds a directory called profile_<name> to your IPython directory. Then you can load this profile by adding --profile=<name> to your command line options. Profiles are supported by all IPython applications.

IPython ships with some sample profiles in IPython/config/profile. If you create profiles with the name of one of our shipped profiles, these config files will be copied over instead of starting with the automatically generated config files.

IPython extends the config loader for Python files so that you can inherit config from another profile. To do this, use a line like this in your Python config file:

load_subconfig('ipython_config.py', profile='default')