StatisticsTutorialATLASItalia17

Very short statistical tutorial (RooFit + RooStats) at ATLAS Italia 2017

Setup

We are using lxplus to setup ROOT. Any other machine with a recent version of ROOT should work (your laptop with ROOT + python + git + virtualenv is suggested. With linux you can easily install everything with apt, yum, dnf, ...). We are using Jupyter notebook as interface.

ssh lxplus
setupATLAS
lsetup ROOT
lsetup git

If you have problem with setupATLAS it may be it is not defined for your account. In this case define it:

export ATLAS_LOCAL_ROOT_BASE=/cvmfs/atlas.cern.ch/repo/ATLASLocalRootBase
alias setupATLAS='source ${ATLAS_LOCAL_ROOT_BASE}/user/atlasLocalSetup.sh'

From this point instructions are not specific for lxplus.

Clone this git repository, you can use the folder as working directory

git clone https://github.com/wiso/StatisticsTutorialATLASItalia17.git
cd StatisticsTutorialATLASItalia17

Now let setup additional software as jupyter. We are doing it with a virtualenv, just copy and paste:

virtualenv -p `which python` venv
source venv/bin/activate
pip install --upgrade pip
pip install --upgrade setuptools
export CC=`which gcc`
pip install ipython jupyter numpy

This should take a couple of minutes.

Create tunnel to your machine

If you are using a remote session (lxplus) you need to redirect the output. If you are using a local computer (your pc) just do:

jupyter notebook

In case you are using a remote session continue to read. We are not using X-redirection, but Jupyter notebook and ssh tunnel. Just copy and paste these commands:

./notebook.sh 7695

Very important: the number here represent a port which should not be used by others (it is quite usual to find collision), so use a random number of four digits different from the one here:

If a collission happens you will find a message as "The port 7695 is already in use, trying another port." It is ok, but take note ok the alternative port used in the message as

Copy/paste this URL into your browser when you connect for the first time, to login with a token:
    http://127.0.0.1:7696/?token=30c3334279e1fbafe2780fd5570081f7131339fa645be274

Then open a new console on your machine (not lxplus) and run the command suggested by the output of the previous commands, but change the port in case of collision, and the , as:

ssh -N -f -L 7696:localhost:7696 @lxplus085.cern.ch

Here 7696 is used instead of 7695 because of a collision. The name of machine is different from you, use the one in the output of the command. Answer 'yes' if a question is prompted. The asked password is the lxplus one.

Open a browser from your machine and connect to url suggest by the output as (the token is a sort of password and different for everybody, as the port)

http://127.0.0.1:7696/?token=30c3334279e1fbafe2780fd5570081f7131339fa645be274

Open the first example "Intro Notebook".

What to do when relogin

If you close the lxplus session, if you want to relogin you just need to do:

ssh lxplus
setupATLAS
lsetup ROOT
lsetup git
cd StatisticalTutorialATLASItalia17
source venv/bin/activate

and then recreate the tunnel.

The exercizes

In the exercises folder you will find some example, some of them need to be completed. The order is:

You can have a look to the solution folder

wiso / statisticstutorialatlasitalia17 Goto Github PK