Installation
You can install Colossus either using the common python package manager pip or by downloading the code directly.
Requirements
Colossus is compatible with both Python 2.7 and Python 3.x. However, the code is developed and mostly tested in Python 3, which is thus the recommended version. Colossus requires the following standard packages:
Some tutorial notebooks also use other packages, for example matplotlib for plotting. In addition, the following dependencies are optional:
astropy (only if the astropy cosmology converter is used)
camb (only if a CAMB power spectrum is requested)
Package installation
The easiest way to install Colossus is by executing
pip install colossus
You might need to prefix this command with sudo. To update the code, execute
pip install --upgrade colossus
If the numpy and scipy packages are not already installed, you can similarly install them with the pip command. For more information, please see the pip documentation.
Repository installation
If you want to edit the code, you might prefer to clone the public BitBucket repository https://bitbucket.org/bdiemer/colossus/src/master/ by executing
git clone git@bitbucket.org:bdiemer/colossus.git
You will also need to manually include Colossus in your $PYTHONPATH variable, for example
by adding this command to your shell’s initialization script (e.g., bashrc):
export PYTHONPATH=$PYTHONPATH:/users/me/code/colossus
where the path is, of course, replaced with the location of Colossus on your system.
If, for some reason, you wish to avoid using mercurial or pip, you can install Colossus manually by downloading the current repository contents from the repository site. The disadvantage of this method is that it makes updating the code relatively cumbersome.
Running unit tests
After installing Colossus, you should run its suite of unit tests to ensure the code works as expected. In python, execute:
from colossus.tests import run_tests
The output should look something like this:
test_get_version (colossus.tests.test_utils.TCVersions) ... ok
test_versions (colossus.tests.test_utils.TCVersions) ... ok
...
test_DK14ConstructorOuter (colossus.tests.test_halo_profile.TCDK14) ... ok
test_DK14ConstructorWrapper (colossus.tests.test_halo_profile.TCDK14) ... ok
----------------------------------------------------------------------
Ran 97 tests in 16.697s
OK
If any errors occur, please send the output to the author.