What is Geant4

Get Geant4

Download Geant4 Examples

The latest Geant4 examples can be found in https://github.com/Geant4/geant4/tree/master/examples. The best way to download a single example from there is described in a StackOverflow post: https://stackoverflow.com/a/70729494/1801749.

For Power Users

compose.yml in this folder provides the following command to quickly start your container with automatic volume and port mapping to the host:

docker compose run geant4

There are two ways to download the compose.yml file:

# direct downloading using curl:
curl -LO https://github.com/jintonic/geant4/raw/main/compose.yml
# or using git:
git clone https://github.com/jintonic/geant4 .

The git command may fail if your ~/geant4 folder is not empty. In that case, you can use the following commands as a workaround:

# create local git repository in the current folder
git init
# connect local git repository with the remote one
git remote add origin https://github.com/jintonic/geant4
# pull remote contents to the local repository
git pull origin main
# map remote and local branches so that `git pull` works in the future
git branch --set-upstream-to=origin/main main

For Apptainer Users

Use the following command to get into the container in a Linux host that has Apptainer installed.

apptainer exec docker://physino/geant4 bash --login

Without the --login option, an interactive, non-login shell will be created for the container, and the host's ~/.bashrc is sourced. In a Ubuntu, Debian, or Arch-based Linux host, ~/.bashrc doesn't source /etc/bashrc in the container, where GEANT4_DATA_DIR is declared to be ~/geant4/data. The --login option is used to create an interactive, login shell, which will source the /etc/profile file in the container before it sources the ~/.bashrc file in the host. The /etc/profile file sources the /etc/bashrc file internally. This way, the GEANT4_DATA_DIR environment variable is defined for the container created.

If GEANT4_DATA_DIR is declared in the host already, it will be inherited by the container. There is no need to declare it again in the container. In this case, --login is not needed. For example, the following combination works just fine.

export GEANT4_DATA_DIR=~/path/to/geant4/data/in/the/host/
apptainer exec docker://physino/geant4 bash

For Developers

This repository is created to avoid Geant4 related stuff (e.g. datasets, examples, etc.) being duplicated in specific Geant4 applications, such as GEARS and MinGLE.