Parameter Listing

We use keyword arguments to pass parameters around to various ARES routines. A complete listing of parameters and their default values can be found in

Here, we’ll provide a brief description of each parameter.

For relatively complex calculations it can be difficult to know / remember which parameters are needed. Because of this, a convenience object called the ParameterBundle was introduced in June of 2016 to package together sets of commonly-used parameters and values. See the following page for more information on creating and using these objects:

also relevant to problem initialization:

Custom Defaults

To adapt the defaults to your liking without modifying the source code (all defaults set in, open the file:


which by default contains nothing:

pf = {}

To craft your own set of defaults, simply add elements to the pf dictionary. For example, if you want to use a default star-formation efficiency of 5% rather than 10%, open $HOME/.ares/ and do:

pf = {'fstar': 0.05}

That’s it! Elements of pf will override the defaults listed in at run-time.

Alternatively, within a python script you can modify defaults by doing

import ares
ares.rcParams['fstar'] = 0.05

This is similar to how things work in matplotlib (with the matplotlibrc file and matplotlib.rcParams variable).

Custom Axis-Labels

You can do the analogous thing for axis labels (all defaults set in Open the file:


which by default contains nothing:

pf = {}

If you wanted to change the default axis label for the 21-cm brightness temperature, from \(\delta T_b \ (\mathrm{mK})\) to \(T_b\), you would do:

pf = {'dTb': r'$T_b$'}

This change will automatically propagate to all built-in analysis routines.