This experiment is a work in progress. Even the name (gam-gate) is temporary.

How to install (short version)

First create an environment (not mandatory but highly advised)

conda create --name gam_env python=3.8
conda activate gam_env

Then install the two packages.

pip install gam-g4
pip install gam-gate
git clone https://gitlab.in2p3.fr/opengamgate/gam-tests.git
cd gam-tests
./all_tests.py

Once installed, you can have a look at all tests files in the following folder: https://gitlab.in2p3.fr/opengamgate/gam-tests/-/tree/master/src

If you already installed the packages and want to upgrade to last version:

pip install gam-g4 -U 
pip install gam-gate -U

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How to install (long version, for developers)

There are three repositories:

• https://github.com/dsarrut/gam-g4 contains the cpp library, linked to Geant4
• https://github.com/dsarrut/gam-gate contains the python library
• https://gitlab.in2p3.fr/opengamgate/gam-tests contains some tests

The gam-g4 lib is composed of two folders:

• The folder gam_g4/g4_bindings contains C++ source code that maps some Geant4 classes into a Python module.
• The folder gam_g4/gam_lib contains additional C++ classes that extends Geant4 functionalities (also mapped to Python).

At the end of the compilation process of gam-g4 a Python module is available, named gam_g4. It is ready to be used from the Python side via the gam-gate python module.

⚠️ This is still work in progress and will probably changes ...

⚠️ Folder and module names are with an underscore (gam_g4) while python package in pip are with a minus sign (gam-g4). Don't ask us why.

1) First, create a Python environment and activate it.

If you use conda:

conda create --name gam_env python=3.8
conda activate gam_env

See: https://conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html

If you dont use conda:

python3 -m venv gam_env 
source gam_env/bin/activate

See: https://docs.python.org/3/tutorial/venv.html

2) Install required softwares (Geant4 and ITK)

Install Geant4 , with Multithreading=ON, and QT visualization. QT should work when install in the python environment, for example with conda install qt.

Install ITK.

3) Clone the repository (with submodules!)

git clone --recurse-submodules https://github.com/dsarrut/gam-g4

4) Compile the c++ part

Go in the folder and:

pip install -e .

It will create some files, ready to be compiled, but will fail, it is "normal" (well, it is not really normal, but the current way. Of course it will be improved).

Then, go in the created folder and cmake :

cd build/temp.linux-x86_64-3.6

cmake -DGeant4_DIR=~/src/geant4/build-geant4.10.07-debug-mt -DPYTHON_EXECUTABLE=~/src/py/miniconda3/envs/gam_env/bin/python -DPYTHON_INCLUDE_DIR=~/src/py/miniconda3/envs/gam_env/include -DPYTHON_LIBRARY=~/src/py/miniconda3/envs/gam/lib/libpython3.so -DITK_DIR=~/src/itk/build-v5.2.0 -DROOT_DIR=~/src/geant4/build-root -DCMAKE_CXX_FLAGS="-Wno-pedantic"  . 

Of course, replace all folders by yours.

Then compile:

make -j 12

5) On linux

Sometimes on Linux machine, you will need to add the following path to find dynamic library :

export LD_PRELOAD=~/src/geant4/build-geant4.10.07-debug-mt/BuildProducts/lib64/libG4processes.so:${LD_PRELOAD}

We dont know yet why this is required and are currently working to improve this.

6) Test

Start python: python and type import gam_g4. The first time, Geant4 data will be downloaded. You can now access some G4 functions in Python.

For example:

import gam_g4
a = gam_g4.G4ThreeVector(0)
print(a)

7) Install the gam-gate python module

Clone the repository:

git clone https://github.com/dsarrut/gam-gate

Then install the module:

cd gam-gate
pip install -e .

Several python's modules will be downloaded and installed (numpy, itk, matplotlib, etc)

8) Tests

You can clone the repository with all tests:

git clone https://gitlab.in2p3.fr/opengamgate/gam-tests.git
cd gam-tests
./all_tests.py