Installation and Setup

The snat_sim package is not available via a package manager, but can be installed directly from the project’s source code. Please follow the steps outlined below to install and configure the package.

Installing the Pipeline

Source code for this project is available on GitHub and can be downloaded directly from the GitHub repository page or by using the git command line utility:

git clone --depth=1 --branch=master https://github.com/LSSTDESC/SN-PWV.git SN-PWV
rm -rf ./SN-PWV/.git

The package can then be installed into your working environment manually, or using pip:

cd SN-PWV
pip install .

If you want to run the package’s test suite, you will need to install the test suite dependencies:

pip install .[tests]

Extra dependencies are also required for building package documentation:

pip install .[docs]

You can check the pipeline has been installed by running:

snat-sim --version

Downloading Light-Curve Sims

Important

Not all parts of this project require existing light-curve simulations. The complete data set takes up several hundred GB of storage. To avoid future headaches, please ensure you actually need this data and don’t already have it available in your working environment.

Simulated light-curve data is hosted on Zenodo and can be downloaded using the wget command. URL’s for various subsets of the data is listed are listed in file_list.txt and can be downloaded as shown below. For convenience, the timeout and tries arguments can be used to indefinitely retry a failed download and the continue flag can be included to avoid restarting a failed download from scratch.

wget --continue --timeout 0 --tries 0 -i data/plasticc/file_list.txt -P /desired/output/directory/

If you have difficulty downloading all the data at once, or if you don’t need the entire data set, try individually downloading the files listed in file_list.txt . The downloaded files will be nested, compressed files using a mix of the .gz and .tar.gz compression formats. You can decompress them using the following commands:

tar -xvzf [FILE TO DECOMPRESS].tar.gz
gunzip [FILE TO DECOMPRESS]/*/*.gz

Configuring Your Environment

The path of the downloaded data needs to be specified in the project environment so that the software knows where to find the simulated light-curves.

export CADENCE_SIMS="[DESIRED DATA DIRECTORY]"

If you are using a conda environment, this can be accomplished automatically by specifying the desired data directory as follows:

# Instantiate the new environment
conda activate [ENV-NAME]

# Go to the environment's home directory
cd $CONDA_PREFIX

# Create files to run on startup and exit
mkdir -p ./etc/conda/activate.d
mkdir -p ./etc/conda/deactivate.d
touch ./etc/conda/activate.d/env_vars.sh
touch ./etc/conda/deactivate.d/env_vars.sh

# Add environmental variables
echo 'export CADENCE_SIMS="[DESIRED DATA DIRECTORY]"' >> ./etc/conda/activate.d/env_vars.sh
echo 'unset CADENCE_SIMS' >> ./etc/conda/deactivate.d/env_vars.sh

# Finally, don't forget to exit your environment
conda deactivate