Simulation and reconstruction framework for the Light Dark Matter eXperiment.

Start Up

ldmx-sw is a large software project and so it is helpful to separate using it to perform physics studies from developing it to fix/improve/enable other studies. In both cases, we use containers to share a fixed software environment, so everyone will need a method for running these containers.

• Install the docker engine
  • Only necessary on personal computers. Shared computing clusters should have apptainer installed.
  • (on Linux personal computers) Manage docker as non-root user
• Install denv

  curl -s https://raw.githubusercontent.com/tomeichlersmith/denv/main/install | sh

  Some folks may see an error about something not being within your PATH, you just need to update your shell's configuration to look for denv within that directory. A program being "in your PATH" can be checked by making sure your shell can find it.

  denv help

  The above should printout a help message instead of a "command not found" message.

Additionally, many folks have gotten used to using ldmx as the command to put programs into the containerized environment in which case you can use the following to add this symlink to your denv installation. (Note: This requires denv to be in your PATH!).

ln -s $(which denv) $(dirname $(which denv))/ldmx

Using

In order to use ldmx-sw, no more dependencies are required! Simply choose the version of ldmx-sw you wish to use with your project.

mkdir my-project
cd my-project
denv init ldmx/pro:v4.0.1 # or some other ldmx-sw version

And then you can run ldmx-sw with a configuration script of your choice.

denv fire my-config.py

More detail on configuration scripts and analyzing the output files is given in the first section of the online manual.

Developing

For development, we use a few more tools to help track our changes and share commands that we use regularly.

[!WARNING] If you are on Windows, make sure to install these tools inside WSL where docker will be run and ldmx-sw will be developed. Since WSL is often a virtual Ubuntu machine, following the instructions for Ubuntu or Linux can be appropriate.

• Make sure git is installed.
  • git is a very common tool used by software developers and so it may already be available.
  • (on MacOS systems) Make sure git lfs is installed. (Test: git lfs prints out a help message instead of an error about lfs not being found.) The default installation of git that is included with Apple's developer tools does not include git lfs which is required by acts to download and unpack one of its own submodules. GitHub has a nice tutorial on how to install git lfs on MacOS.
• Install just
  • This tool is not required but it is highly encouraged. The recipes we share via the justfile can be run without just but are longer to type.

One can install just in a similar way to denv. Below is an example where the destination directory is set to the same one as the default for denv (~/.local/bin).

curl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh |\
  bash -s -- --to ~/.local/bin

Other package manager options are available as well. You will probably want to make sure just's tab complete is available. If you press just -<Tab><Tab> and nothing is listed, then the tab complete is not present and you must manually install it. This can be accomplished by including its completions within your shell's configuration script. For example, in bash, we would add the following to your ~/.bashrc file.

eval "$(just --completions bash)"

If you are not in bash, look to your shell's documentation on where to place this line. just supports many popular shells including bash, zsh, and fish.

With these additional tools, developers can clone the repository and start development.

git clone --recursive git@github.com:LDMX-Software/ldmx-sw.git

[!NOTE] You need to setup an SSH-key with your GitHub account on the computer you are using.

cd ldmx-sw
just # no arguments prints out the possible options
just init # initialize a new development environment (once per clone)
just configure build test # configure ldmx-sw, build it, then test it

Maintainer

Contributors