Instructions for Leonardo

On leonardo @CINECA, Spack is already installed as a module, and the user just has to load it and then create and configure the environment:

1. load Spack:

   module load spack/0.19.1-d71
   

2. create and activate the environment with the following commands:

   spack env create -d spack_env_name
   spack env activate [-p] ~/spack_env_name
   

   Note that the -d option will create the environment in the current folder, typically the home folder but can be a dedicated one ¹. The -p is just a flag to visualize the environment is active.

3. add Python and py-pip to the environment and install them

   spack add python py-pip
   spack -d install
   

   In this way, the (last) preferred version of Python will be installed. You can do spack find to see which packages have been installed.
   Tip

   In case you want to install a specific Python version, you can search and choose the preferred version through the commands

   spack info python
   spack add python@version
   

4. install Python packages needed to run the workflow in the environment

   pip install -r /path-to-software/cheese-ptha-master/requirements.txt
   

   The file requirements.txt is provided with the workflow.

   Warning

   You could get the error ModuleNotFoundError: No module named 'pip'. If this is the case, you have to load py-pip before installing the Python packages

   spack load py-pip
   

The environment is ready. For any new session, of course, it must be activated by the commands

module load spack/0.19.1-d71
spack env activate [-p] ~/spack_env_name

The same two lines should be inserted within the file load_env.source (see the installation instructions).