This script generates the initial conditions and parameterfile for a gadget run with an isolated galaxy. It is inteded for use with the fixed potential InterStellarGadget. It also provides a much more readable and portable way to write gadget parameterfiles.

To set up a run, simply run the parser script followed by the .ini file, for example from the 'example' directory:

python3 ../parser.py test.ini

This will generate the initial conditions (sans dark matter halo, of course). These follow exponential radial profiles and sech^2 profiles for the gas and stars.

A quick note: using the --pfile option will ensure that the script only generates the parameterfile, and then quits.

The custom (i.e. non base-gadget) paramters are:

[ParameterFile]

# Name and location of gadget file
ParameterFile: test.param


[NFW]

# Scale lengths and masses are given in simulation units
NFWc: 40
NFWScaleRadius: 20
HaloMass: 1e12


[Gas]

GasScaleRadius: 10
# Particles are generated out to radius GasScaleRadius*MaxGas
MaxGas: 30
GasScaleHeight: 1
GassMass: 1e10
GasParticles: 1e3
GasDispersion: 0


[Stars]

StarScaleRadius: 10
MaxStar: 30
StarScaleHeight: 2
StarMass: 5e10
StarParticles: 1e3
StarDispersion: 0

Of course, this software is supplied with the usual:

• No warranty
• No guarantee that it will produce convergent results
• No guarantee that it will not blow up your computer.

This script is not parallelized well, in particular the routines that generate the exponential profile are very lousy.