Using Jupyter at Jefferson Lab!
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Frequently Asked Questions about Jupyter at Jefferson Lab
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Where are my notebooks stored?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For security reasons the jupyter server does not have write access
outside a narrow area. When you log in to jupyter.jlab.org, the file
browser will only show you the files in the directory
``/group/jupyterusers/$USER``. All files outside that directory are only
readable, not writable. You can, however, login to an interactive farm
node and apply version control to the files in
``/group/jupyterusers/$USER``.

How do I use python on interactive farm nodes?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Python is installed on interactive farm nodes at ``/apps/python``. You
can add the python executables to the shell search path automatically at
login by including the following line in your ``.bashrc`` file:

::

    export PATH=/apps/python/3.4.3/bin:$PATH

Instead of the explicit version number you can also specify ``PRO``
which points to python 3.4.3 (as of April 2018).

How do I install a new package?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

A selection of commonly used packages are installed system-wide. If a
package you wish to use is not installed system-wide, you can do so
using the interactive farm environment. After adding the python
executables to the shell search path, you will have access to ``pip``
for installing packages in your user base directory ``~/.local``. You
can then install packages using, for example:

::

    pip install --user --upgrade uproot

Why can't I delete files or directories?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Due to security restrictions on the jupyter.jlab.org server, the attempts by jupyter to move deleted files to the trash folder fail. While JLab CC works on resolving this through the jupyter configuration, a work-around is to log in to an interactive node and delete the files or directories by hand. Their location is ``/group/jupyterusers/$USER``.