Getting Started

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Requirements

• python >= 3.x

  • numpy

  • scipy

  • cython

  • h5py

  • matplotlib

  • psutil

  • joblib

  • six

  • astropy

  • yt >= 4.0

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Installation

Python and friends

Since this is a python package, you must have python installed! CAESAR formally requires python-3. Some basic functionality is still compatible with python-2, but we have discontinued further support for this in CAESAR.

We strongly encourage using a pre-packaged python distribution, such as Anaconda. This will install an isolated python environment in your home directory giving you full access to install and change packages without fear of screwing up your system’s default python install. Another advantage is that it comes with nearly everything you need to get started working with python (numpy/scipy/matplotlib/etc).

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Dependencies

Installing the main dependencies is very easy under Anaconda, or using the python package manager pip.

$> conda install numpy scipy cython h5py matplotlib psutil joblib six astropy

Alternatively, if you do not wish to use Anaconda, these can all be installed under pip by replacing conda with pip in the line above. Some of these automatically come with Anaconda, but the above command will update these to the latest version if needed.

Be aware that in order for h5py to properly compile you must first have HDF5 correctly installed (via e.g. apt-get, brew, or manual compilation) and in your respective environment paths.

The optional galaxy/halo photometry computation in CAESAR requires python-fsps, which is a python wrapper for the FSPS fortran package. Please follow their installation instructions to install this. Furthermore, you will also need two other packages that are only available via pip:

$> pip install synphot extinction

If you wish to use the MPI driver to run single instances of Caesar over many cores via MPI, it is also necessary to install mpi4py:

$> conda install mpi4py

Note that CAESAR is natively OpenMP-parallel, and the MPI implementation may be system-specific.

If you wish to work with galaxy and halo particle lists (for instance to compute your own quantities) it is highly recommended that you install pygadgetreader:

$> git clone https://github.com/dnarayanan/pygadgetreader.git
$> cd pygadgetreader
$> python setup.py install

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yt

CAESAR builds on the yt simulation analysis toolkit. CAESAR requires yt version >=4.0, though a lot of functionality will still work with yt-3.6+.

We recommend installing yt via Anaconda:

$> conda install -c conda-forge yt

but other installation options are described here.

If you already have yt, you can check your version using yt version, and update if necessary.

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CAESAR

Now that we have all of the prerequisites out of the way we can clone and install CAESAR:

$> git clone https://github.com/dnarayanan/caesar.git
$> cd caesar
$> python setup.py install

Once it finishes you should be ready to finally get some work done!

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Updating

To update CAESAR simply pull the changes and reinstall:

$> cd caesar
$> git pull
$> python setup.py install