Installation using conda

Adding RSA key to Github

To clone the NNPDF Github repositories, you must add a public RSA key to Github.

• Checking for an existing RSA key

  Firstly, check if your machine has already generated an RSA key. This can be done by the following:

    cd ~/.ssh
    ls -a
  

  and verify the files id_rsa and id_rsa.pub exist. An alternative is to perform find ~ -name 'id_rsa.*' and verify id_rsa.pub is found.

• Generating an RSA key

  If no RSA key exists use the command

    ssh-keygen
  

  and follow the instructions to generate an RSA key.

• Adding the RSA key to Github

  Copy the public RSA key stored in id_rsa.pub to your clipboard using

    cat ~/.ssh/id_rsa.pub
  

  and copying the output.

  The public RSA key must be pasted to Github here and clicking on the ‘New SSH key’ button. Enter an appropriate title and paste the RSA Key.

Obtain the helper script

A helper script exists to aid the configuration. To obtain it use:

	mkdir nnpdfgit
	cd nnpdfgit
	git clone git@github.com:NNPDF/binary-bootstrap.git

• Execute the script

    ./binary-bootstrap/bootstrap.sh
  

  The script will ask you for the password of the NNPDF private repository, which can be found here

• Path: the conda installer will ask to add the conda bin path to the default $PATH environment variable (by editing your .bashrc file). Confirm this unless you know that you have a specific reason not to. Note that newer versions of conda give the option of having conda available, but not any environment (which you have to enable explicitly by either having conda activate in .bashrc or typing it each time you want to use the environment). On remote machines, the addition to .bashrc should read as follows

    if shopt -q login_shell; then
    	. <path-to-conda>/etc/profile.d/conda.sh
    	conda activate
    fi
  

the if condition is important because conda activate prints to the standard output, which interferes with commands like scp and rsync.

• Note that the script may ask you to perform some actions manually ( e.g. it will not overwrite your existing conda configuration). Please pay attention to the output text of the script.

Installing the NNPDF code

After the helper script has run, navigate to the miniconda3 installation directory, by default this is ~/miniconda3, and run the command

	. ./etc/profile.d/conda.sh
	conda activate
	conda install nnpdf

This will provide functioning C++ and Python executables.

Note: The installer will set up it’s own version of the LHAPDF code, with its own path for storing PDFs, which can be seen running lhapdf –help. If you have an exiting folder with LHAPDF grids, you may want to either move, symlink or copy them to the new path (depending on whether you want to keep around the older installation). The command for symlinking would be something like:

ln -s <old path>/share/LHAPDF/* <new path>/miniconda3/share/LHAPDF

This will avoid symlinking the existing LHAPDF configuration, which may be corrupted or incompatible. You should make sure only the grid folders are transferred if you copy or move instead.

Details about conda configurations can be found here.

~/.condarc

	channels:
	 - https://packages.nnpdf.science/conda-private
         - https://packages.nnpdf.science/conda
	 - defaults
         - conda-forge

Note: The NNPDF packages were previous hosted in a different location (zigzah.com). You must remove these channels and use nnpdf.science instead.

The private packages are password protected (with http basic_auth). In order for conda to be able access them, a ~/.netrc file needs to contain the password. It is also convenient to add the validphys password in order to be able to programmatically access the validphys server. This is used by some validphys tools.

~/.nertc

	machine packages.nnpdf.science
		login nnpdf
		password machinist-proton-saddling

machine vp.nnpdf.science login nnpdf password nnpdfserver!