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---+!! CMS Data Analysis School Pre-Exercises - Second Set

%TOC{title="Contents:"}%
---++ Introduction

Welcome to the second set of CMSDAS pre-exercises. As you know by now, the
purpose of the pre-workshop exercises is for prospective workshop attendees to
become familiar with the basic software tools required to perform physics
analysis at CMS before the workshop begins. Post the answers in the online response form available from
*the course web area*:
      * [[https://indico.cern.ch/event/662371/page/11810-pre-exercisesinstructions][CMSDAS@LCPS2018 pre-exercises indico page with submit form links]]
<!--   * [[https://espace.cern.ch/learncms/AnalysisSchoolFNALJan17/SitePages/Home.aspx][for CMSDAS@LPC 2017, Fermilab]]-->
<!--   * <a href="https://espace.cern.ch/learncms/CMSObjectSchoolBariSep17/Lists/Submit%20your%20preexercises/AllItems.aspx" title="Pre-exercises answers">for CMSPOS@Bari_2017</a>-->
A large amount of additional information about these exercises is available in the twikis that we reference. Please remember that twikis evolve but aim to provide with the best information at any given time. If problems are encountered please e-mail the
   * *LPC contact* =CMSDASATLPC@fnal.gov= for !CMSDAS@LPC2018
<!--   * *Bari contact* [[mailto:leonardo.cristella@ba.infn.it][leonardo.cristella@ba.infn.it]] for CMSPOS@Bari2017-->
with a detailed description of your problem. The instructors will be delighted to help you.  
   * Alternately for !CMSDAS@LPC2018: Join the *!CMSDAS@LPC2018 Mattermost team*: https://mattermost.web.cern.ch/signup_user_complete/?id=5tnsnpi7rjdj3d85zeh5i6573c
      * Mattermost PreExercises Chat channel using CERN login: https://mattermost.web.cern.ch/cmsdaslpc2018/channels/pre_exercises

The Second Set of exercises begins with [[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_7_Slim_MiniAOD_sample_i][Exercise 7]]. We will use Collision data events and simulated events (Monte Carlo (MC)). To comfortably work with these files, we will first make them smaller by selecting only the objects that we are interested in (electrons and muons in our case).

The collision data events are stored in =DoubleMuon.root=. =DoubleMuon= refers here to the fact, that when recording these events, we believed that there are two muons in the event. This is true most of the time, but other objects can fake muons, hence at closer inspection we might find events that actually don't have two muons.

The MC file is called DYJetsToLL. You will need to get used to cryptic names like this if you want to survive in the high energy physics environment! The MC file contains Drell Yan events, that decay to two leptons and that might be accompanied by one or several jets.

[[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_8_Use_FWLite_on_the_Min][Exercises 8]] and
[[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_9_Re_run_the_above_exec][Exercise 9]] are using [[SWGuideFWLite][FWLite]]
(*Frame Work Lite*). This is an interactive analysis tool integrated with the
CMSSW EDM (Event Data Model) Framework. It allows you to automatically load the
shared libraries defining CMSSW data formats and the tools provided, to easily
access parts of the event in the EDM format within ROOT interactive sessions.
It reads produced ROOT files, has full access to the class methods and there
is no need to write full-blown framework modules. Thus having FWLite
distribution locally on the desktop one can do CMS analysis outside the full
CMSSW framework. In these two exercises, we will analyze the data stored in a
MiniAOD sample using FWLite. We will loop over muons and make a Z mass peak.

[[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_10_Fireworks_CMS_Event][Exercise 10]] and [[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_11_Run_Fireworks_locall][Exercise 11]] are on the CMS events display called [[CMSPublic.WorkBookFireworks][Fireworks]]. Fireworks is the CMS event display project. Data handling is greatly simplified by using only reconstructed information and ideal geometry. Data is presented via graphical and textual views. Fireworks provides an easy to use interface which allows a physicist to concentrate only on the data in which he is interested in. One can select which events (e.g. require a high energy muon), what data (e.g. which track list) and which items in a collection (e.g. only high-pt tracks) to show.

<b>We assume that having done the first set of pre-exercises by now, one is comfortable with logging onto =cmslpc-sl6.fnal.gov=
<!--</b>for CMSDAS@LPC_2017 or <b><span>cmspos01.recas.ba.infn.it</span></b> for CMSPOS@Bari_2017<b>-->
 and setting up the cms environment.</b>

*NOTE:*
Legend of colors for this tutorial:
<pre style="font-size: 13px" class="command">
GRAY background for the commands to execute  (cut&paste)
</pre>
<pre style="font-size: 13px" class="output">
GREEN background for the output sample of the executed commands
</pre> 
<pre style="font-size: 13px" class="cfg">
BLUE background for the configuration files  (cut&paste)
</pre>
<pre style="font-size: 13px" class="code">
PINK background for the code (EDAnalyzer etc.)  (cut&paste)
</pre>

---++ Obtain a CERN account (in case you don't have one already)

   * Use the following link for a CMS CERN account: [[https://account.cern.ch/account/Management/NewAccount.aspx][CMS CERN account]]
      * A CERN account is needed, for example, to login in to any e-learning web-site, or obtain a file from the afs area. A CERN account will be needed for future exercises.
      * *Obtaining a CERN account can be time-consuming and requires people at CERN to process applications during business hours. The relevant institutional team leader must start the CERN account request. Try to initiate this process as early as possible.*

---++ Obtain a Grid Certificate and CMS VO registration

   * A Grid Certificate and CMS VO registration will be needed for the Grid Exercises. The registration process can be time-consuming (actions by several people are required), so it is important to start it as soon as possible. There are two main requirements which can be simply summarized: A certificate ensures that you are who you claim to be. A registration in the VO recognizes you (identified by your certificate) as a member of CMS. Use the following link for this: [[CMSPublic.WorkBookRunningGrid#GetCert][Get Your Grid Certificate and CMSVO]]. Both are needed to submit jobs on the Grid. Make sure you follow any additional instructions for US-CMS users.

---++ Exercise 7 - Slim MiniAOD sample from [[SWGuideCMSDataAnalysisSchoolPreExerciseFirstSet#Exercise_6_Familiar_with_MiniAOD][Exercise 6]] to reduce its size by keeping only Muon and Electron branches

In order to reduce the size of the MiniAOD we would like to keep only the =slimmedMuons= and =slimmedElectrons= objects and drop all others. The config files should now look like
[[%ATTACHURL%/slimMiniAOD_MC_MuEle_cfg.py.txt][slimMiniAOD_MC_MuEle_cfg.py]] and [[%ATTACHURL%/slimMiniAOD_data_MuEle_cfg.py.txt][slimMiniAOD_data_MuEle_cfg.py]].
To work with this config file and make the =slim= MiniAOD, execute the following steps in the directory =YOURWORKINGAREA/CMSSW_9_3_2/src=

1. Cut and paste the script [[%ATTACHURL%/slimMiniAOD_MC_MuEle_cfg.py.txt][slimMiniAOD_MC_MuEle_cfg.py]] and [[%ATTACHURL%/slimMiniAOD_data_MuEle_cfg.py.txt][slimMiniAOD_data_MuEle_cfg.py]]
in its entirety and save it with the same name. Open with your favorite editor and take a look at these python files. The number of events has been set to 1000:

<pre class="command">process.maxEvents = cms.untracked.PSet( input = cms.untracked.int32(1000) )
</pre>

To run over all events in the sample, one can change it to -1.

2. Now run the following command:
<pre class="command">cmsRun slimMiniAOD_MC_MuEle_cfg.py </pre>

This produces an output file called =slimMiniAOD_MC_MuEle.root= in your =$CMSSW_BASE/src= area.

3. Now run the following command:
<pre class="command">cmsRun slimMiniAOD_data_MuEle_cfg.py </pre>

This produces an output file called =slimMiniAOD_data_MuEle.root= in your =$CMSSW_BASE/src= area.

On opening these two MiniAODs one observes that only the =slimmedMuons= and
the =slimmedElectrons= objects are retained as intended.

To find the size of your MiniAOD execute following Linux command:

<pre class="command">ls -lh slimMiniAOD_MC_MuEle.root</pre>

and

<pre class="command">ls -lh slimMiniAOD_data_MuEle.root</pre>

You may also try the following:

To know the size of each branch, use the =edmEventSize= utility as follows (also explained in [[SWGuideCMSDataAnalysisSchoolPreExerciseFirstSet#Exercise_5_EDM_Event_Data_Model][First Set of Exercises]] ):

<pre class="command"> edmEventSize -v slimMiniAOD_MC_MuEle.root</pre>

and

<pre class="command"> edmEventSize -v slimMiniAOD_data_MuEle.root</pre>

To see what objects there are, open the ROOT file as follows and browse to the MiniAOD samples as you did in [[SWGuideCMSDataAnalysisSchoolPreExerciseFirstSet#Exercise_6_Familiar_with_MiniAOD][Exercise 6]]:

Here is how you do it for the output file slimMiniAOD_MC_MuEle.root

<pre class="command">root -l slimMiniAOD_MC_MuEle.root; 
TBrowser b;
</pre>

OR

<pre class="command">root -l
TFile *theFile = TFile::Open("slimMiniAOD_MC_MuEle.root");
TBrowser b;
</pre>

To quit ROOT application, execute:
<pre class="command">.q
</pre>

%RED% For !CMSDAS@LPC2018 please submit your answers at the [[https://goo.gl/forms/uwyrmHNqZT5q5MAM2][Google Form second set]].%ENDCOLOR%

%RED% QUESTION 7.1a - What is the size of the MiniAOD slimMiniAOD_MC_MuEle.root? %ENDCOLOR%

%RED% QUESTION 7.1b - What is the size of the MiniAOD slimMiniAOD_data_MuEle.root? %ENDCOLOR%

%RED% QUESTION 7.2a - What is the mean eta of the muons for MC? %ENDCOLOR%

%RED% QUESTION 7.2b - What is the mean eta of the muons for data? %ENDCOLOR%

%RED% QUESTION 7.3a - What is the size of the output file compared to the original sample?%ENDCOLOR%

%RED% QUESTION 7.3b - Is the mean eta for muons for MC and data the same as in the original sample in Exercise 6? %ENDCOLOR%

---++ Exercise 8 - Use FWLite on the MiniAOD created in [[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_7_Slim_MiniAOD_sample_i][Exercise 7]] and make a Z Peak (applying =pt= and =eta= cuts)

FWLite (pronounced "framework-light") is basically a ROOT session with CMS data format libraries loaded. CMS uses ROOT to persistify data objects. CMS data formats are thus "ROOT-aware"; that is, once the shared libraries containing the ROOT-friendly description of CMS data formats are loaded into a ROOT session, these objects can be accessed and used directly from within ROOT like any other ROOT class!

In addition, CMS provides a couple of classes that greatly simplify the access to the collections of CMS data objects. Moreover, these classes (Event and Handle) have the same name as analogous ones in the Full Framework; this mnemonic trick helps in making the code to access CMS collections very similar between the FWLite and the Full Framework.

In this exercise we will make a =ZPeak= using our data and MC sample. We will use the corresponding slim MiniAOD created in [[SWGuideCMSDataAnalysisSchoolPreExerciseSecondSet#Exercise_7_Slim_MiniAOD_sample_i][Exercise 7]]. To read more about FWLite, have a look at =Section 3.5= of =Chapter 3= of the [[CMSPublic.WorkBook][WorkBook]].

We will first make a =ZPeak=. We will loop over the =slimmedMuons= in the MiniAOD and get the mass of oppositely charged muons. These are filled in a histogram that is written to an output ROOT file.

First make sure that you have the MiniAODs created in Exercise 7. They should be called =slimMiniAOD_MC_MuEle.root= and =slimMiniAOD_data_MuEle.root=.

<!--Further you would need to check the following two packages with corresponding tags from the CVS.

=PhysicsTools/FWLite V02-03-14=

=PhysicsTools/UtilAlgos V08-02-15-01=-->

1. Go to the src area of current CMSSW release
<pre class="command">
cd $CMSSW_BASE/src
</pre>
The environment variable =CMSSW_BASE= will point to the base area of current CMSSW release.

2. Check out a package from GitHub.

Make sure that you get github setup properly as in
[[%SCRIPTURL{"view"}%auth/CMS/SWGuideCMSDataAnalysisSchoolPreExerciseFirstSet#Obtain_a_github_account][obtain a GitHub account]].  It's particularly important to set up ssh keys so that you can check out code without problems:
https://help.github.com/articles/generating-ssh-keys

To check out the package, run:
<pre class="command">
git cms-addpkg PhysicsTools/FWLite
</pre>

<!--%RED% For any github related issues please send an email to: =hn-cms-git@cern.ch= %ENDCOLOR%-->

Then to compile the packages, do

<pre class="command">scram b
cmsenv
</pre>

%RED% Note: You can try =scram b -j 8= to speed up the compiling. Here =-j 8= will compile with 8 cores. When occupying several cores to compile, you will also make the interactive machine slower for others, since you are using more resources. Use with care!

%RED% Note 2: It is necessary to call =cmsenv= again after compiling this package because it adds executables in the =$CMSSW_BASE/bin= area.

3. To make a Z peak, we will use the FWLite executable called =FWLiteHistograms=. The corresponding code should be in =$CMSSW_BASE/src/PhysicsTools/FWLite/bin/FWLiteHistograms.cc=

With this executable we will use the command line options. More about these can be learned from SWGuideCommandLineParsing.

To make a =ZPeak= from this executable, using the MC MiniAOD, run the following command (which will not work out of the box, see below):

<pre class="command">FWLiteHistograms inputFiles=slimMiniAOD_MC_MuEle.root outputFile=ZPeak_MC.root maxEvents=-1 outputEvery=100</pre>

You can see that you will get the following error:

<pre class="output"><verbatim>terminate called after throwing an instance of 'cms::Exception'
  what():  An exception of category 'ProductNotFound' occurred.
Exception Message:
getByLabel: Found zero products matching all criteria
Looking for type: edm::Wrapper<std::vector<reco::Muon> >
Looking for module label: muons
Looking for productInstanceName: 

The data is registered in the file but is not available for this event</verbatim></pre>

This error occurs because your input files =slimMiniAOD_MC_MuEle.root= is a MiniAOD and does not contain =reco::Muon= whose label is =muons=. It contains, however, =slimmedMuons= (check yourself by opening the root file with =ROOT= browser). However, in the code [[https://github.com/cms-sw/cmssw/blob/CMSSW_7_3_X/PhysicsTools/FWLite/bin/FWLiteHistograms.cc][FWLiteHistograms.cc]] there are lines that say:

<pre class="code">using reco::Muon;
</pre>

and

<pre class="code">event.getByLabel(std::string("muons"), muons);
</pre>

This means you need to change =reco::Muon= to =pat::Muon=, and =muons= to =slimmedMuons=.

To implement these changes, open the code =$CMSSW_BASE/src/PhysicsTools/FWLite/bin/FWLiteHistograms.cc=. In this code, look at the line that says:

<pre class="code">using reco::Muon;
</pre>

and change it to
<pre class="code">using pat::Muon;
</pre>

and in this:

<pre class="code">event.getByLabel(std::string("muons"), muons);
</pre>

and change it to
<pre class="code">event.getByLabel(std::string("slimmedMuons"), muons);
</pre>

Now you need to re-compile:

<pre class="command">scram b</pre>

Now again run the executable as follows:

<pre class="command">FWLiteHistograms inputFiles=slimMiniAOD_MC_MuEle.root outputFile=ZPeak_MC.root maxEvents=-1 outputEvery=100</pre>

You can see that now it runs successfully and you get a =ROOT= file with a histogram called =ZPeak_MC.root=. Open this =ROOT= file and see the Z mass peak histogram called =mumuMass=. Answer the following question.

%RED% QUESTION 8.1a - What is mean mass of the ZPeak for your MC MiniAOD? %ENDCOLOR%

%RED% QUESTION 8.1b - How can you increase statistics in your ZPeak histogram? %ENDCOLOR%

4. Now a little bit about the command that you executed.

In the command above, it is obvious that =slimMiniAOD_MC_MuEle.root= is the input file, =ZPeak_MC.root= is output file. =maxEvents= is the events you want to run over. You can change it any other number. The option =-1= means running over all the events which is 1000 in this case. =outputEvery= means after how any events should the code report the number of event being processed. As you may have noticed, as you specified, when your executable runs, it says =processing event:= after every 100 events.

If you look at the code [[https://github.com/cms-sw/cmssw/blob/CMSSW_7_3_X/PhysicsTools/FWLite/bin/FWLiteHistograms.cc][FWLiteHistograms.cc]]
, it also contains the defaults corresponding to the above command line options. Answer the following question:

%RED% QUESTION 8.2 - What is the default name of the output file? %ENDCOLOR%

---++ Exercise 9 - Re-run the above executable with the data MiniAOD

Re-run the above executable with the data MiniAOD file called =slimMiniAOD_data_MuEle.root= as follows:

<pre class="command">FWLiteHistograms inputFiles=slimMiniAOD_data_MuEle.root outputFile=ZPeak_data.root maxEvents=-1 outputEvery=100</pre>

This will create an output histogram =ROOT= file called =ZPeak_data.root=

Then answer the following question.

%RED% QUESTION 9a - What is mean mass of the ZPeak for your data MiniAOD? %ENDCOLOR%

%RED% QUESTION 9b - How can you increase statistics in your ZPeak histogram? %ENDCOLOR%

---++ Exercise 10 - Fireworks - CMS Event Display

Fireworks is the CMS event-display project and cmsShow is the official name of
the executable. Both names are used interchangeably. With this tool
one can display events for physics. The core of Fireworks is built on top of
the Event Data Model (EDM) and the light version of the software framework
(FWLite). The Event Visualization Environment (EVE) of ROOT is used to manage
3D and 2D views, selection, and user-interaction with the graphics windows.
Several EVE components were developed in a collaboration between the Fireworks
and ROOT teams. The event display operates using simple plugins which are
registered into the system to perform conversion from EDM collections into
their visual representations. As a guiding principle, Fireworks shows only
what is available in the EDM event-data, no reconstruction or result
enhancement is performed internally. Visibility of collection elements can be
filtered via a generic expression.

An instructive introduction to the features of Fireworks is given in this [[http://cern.ch/cms-sdt/fireworks/demo.mov][video tutorial]]. The video tutorial shows an older version of Fireworks, as some elements of user interface (UI) have changed. With a little bit of browsing through the new UI, you will be able to find all the functionalities. Lots of them are very helpful, and they are nicely explained in the video.

Please be aware that for any issues with fireworks display, first have a look at the twiki WorkBookFireworksHowToFix and then send email to the fireworks support list at =fireworks-support@cernSPAMNOT.ch=.

1. First we will look at the event display from =YOURWORKINGAREA/CMSSW_9_3_2/src=. After you login and do =cmsenv=, execute the following command from =YOURWORKINGAREA/CMSSW_9_3_2/src=. We will look at the collision data that you have used in earlier exercises:

<pre class="command">
cmsShow root://cmseos.fnal.gov//store/user/cmsdas/2017/pre_exercises/DYJetsToLL.root
</pre>
If you get an error about incompatible data, try with this method:
<pre class="command">
cmsShow --no-version-check root://cmseos.fnal.gov//store/user/cmsdas/2017/pre_exercises/DYJetsToLL.root
</pre>

Depending on the connection you have, it might take a while to open Fireworks, since the GUI has to be forwarded to your local computer. It will pop a window like this:

%TWISTY{mode="div" showlink="Show result..." hidelink="Hide result..." remember="on" 
                showimgleft="%ICONURLPATH{toggleopen-small}%" 
                hideimgleft="%ICONURLPATH{toggleclose-small}%"}%
<img alt="cmsShow_MC_730pre1.png" src="%ATTACHURLPATH%/cmsShow_MC_730pre1.png" width="594" />
%ENDTWISTY%

You will soon realise that it is very slow. This is because the data file is not stored locally. Let us copy a few events locally using a =config=. You can use this config file to copy events from any file that you can access locally. To achieve this, open the file [[%ATTACHURL%/copy_CMSDAS_cfg.py.txt][copy_CMSDAS_cfg.py]], select the text entirely and save it in a file with the same name in =YOURWORKINGAREA/CMSSW_9_3_2/src=. Now execute the following command: 
<pre class="command">cmsRun copy_CMSDAS_cfg.py
</pre>

This will copy 100 events to a file called =DYJetsToLL_n100.root=. If you want to copy less events, you are free to change the number =100= to a different value in the following line in =copy_CMSDAS_cfg.py=:

<pre class="cfg">process.maxEvents = cms.untracked.PSet( input = cms.untracked.int32(100) )</pre>

To also copy the data file, open =copy_CMSDAS_cfg.py= and replace =DYJetsToLL= with =DoubleMuon= everywhere, there should be two occurrences of =DYJetsToLL=. Again run the config file for data as:

<pre class="command">cmsRun copy_CMSDAS_cfg.py</pre>

This will copy 100 collision events to a file called =DoubleMuon_n100.root=.

Now we are ready to play with =Fireworks= for the event display.

To open the =Fireworks= event display for the collision data file, do the following:

<pre class="command">cmsShow DoubleMuon_n100.root
</pre>

This will open the Fireworks display window as shown in the snapshot below. This window has several parts that can be swapped or undocked for a separate view. Now do the following after the Fireworks windows open.

%TWISTY{mode="div" showlink="Show result..." hidelink="Hide result..." remember="off" 
                showimgleft="%ICONURLPATH{toggleopen-small}%" 
                hideimgleft="%ICONURLPATH{toggleclose-small}%"}%
<img alt="event_display_804.png" src="%ATTACHURLPATH%/event_display_804.png" width="594" />
%ENDTWISTY%

1. As you see the very first event displayed has an event number =133325096=.

2. On the top left part that says ="Summary View/Add Collection"= uncheck all collections EXCEPT =Muons=. As you uncheck, notice how the different color coded objects disappear from the main display sub-window that says ="Rho Phi"=.

3. Now look at the =Muons= collection from the left side menu. Click the arrow to the left, to see some basic properties of the muon candidates.

%RED% QUESTION 10.1a - What is pT of the highest pT muon that you see in the first event? %ENDCOLOR%

%RED% QUESTION 10.1b - What is Run number? %ENDCOLOR%

%RED% QUESTION 10.1c - What is the LS number? %ENDCOLOR%

%RED% QUESTION 10.2 - How many *tracks* does the first event have? %ENDCOLOR%

You can also open the =DYJetsToLL_n100.root= file and display its events too.

---++ Exercise 11 - Run Fireworks locally from Desktop

As you noticed, first accessing a remote file for =cmsShow= makes things run slowly. To overcome that you copied some events to your interactive machine. However, despite having the =data= and =MC= files in your working area, the display is still very slow. The fastest way to run Fireworks is to have everything locally on your laptop. In this exercise, we will first download fireworks and then run the display. We will also copy the =ROOT= files locally to the laptop/desktop.

First copy the =ROOT= files locally to your laptop. To do that, we use =scp= (secure copy), which copies files with the =ssh= protocol. Alternate copy methods can be found [http://uscms.org/uscms_at_work/computing/setup/uaf_data_transfer.shtml][here for the cmslpc-sl6 cluster]].

While on your laptop, do the command:
<pre class="command">
scp USERNAME@SERVER:YOURWORKINGAREA/CMSSW_9_3_2/src/DYJetsToLL_n100.root .
scp USERNAME@SERVER:YOURWORKINGAREA/CMSSW_9_3_2/src/DoubleMuon_n100.root .
</pre>

Replace USERNAME with your username, SERVER with the server you have been using (=cmslpc-sl6.fnal.gov=, this presumes you have already gotten a valid Kerberos ticket),
and YOURWORKINGAREA with the path to your working area (find it with the =pwd= command while logged into the cmslpc-sl6 cluster).

Now we will get the fireworks executable locally. To do this, please follow the instructions in the [[CMSPublic.WorkBookFireworks][WorkBookFireworks]] twiki. Just download, uncompress and come back here.

Next, copy the root files to directory =cmsShow-X.Y=. To open the event display, go into the =cmsShow-X.Y= directory and execute the following:
<pre class="command">./cmsShow DoubleMuon_n100.root
</pre>

%RED% QUESTION 11 - How many primary vertices are in the first event of DoubleMuon_n100.root? %ENDCOLOR%

%RED% For !CMSDAS@LPC2018 please submit your answers at the [[https://goo.gl/forms/uwyrmHNqZT5q5MAM2][Google Form second set]].%ENDCOLOR%

Link to SWGuideCMSDataAnalysisSchoolPreExerciseFirstSet

Link to SWGuideCMSDataAnalysisSchoolPreExerciseThirdSet

Link to SWGuideCMSDataAnalysisSchoolPreExerciseFourthSet

Link to SWGuideCMSDataAnalysisSchoolPreExerciseFifthSet

Link to SWGuideCMSDataAnalysisSchoolPreExerciseSixthSet

Questions/Problems/Suggestions - mailto: =basil.schneider@cern.ch=.

%TWISTY{mode="div" showlink="Show " hidelink="Hide "  firststart="hide"
showimgright="%ICONURLPATH{toggleopen-small}%" 
hideimgright="%ICONURLPATH{toggleclose-small}%"}%
| *Reviewer/Editor and Date (copy from screen)* | *Comments* |
| Main.Basil.Schneider, Main.MargueriteTonjes - 22 October 2017 | Updated to Run2/2017 for CMSDAS@LPC2018 |
| Main.AdrianPerieanu - 15 July 2016 | Updated to CMSSW_8_0_6 for CMSDAS@HH |
| Main.NitishDhingra - 03 October 2013 | Updated to CMSSW_5_3_11 for CMSDAS@Kolkata  |
| Main.NitishDhingra - 22 July 2012 | Updated to CMSSW_5_2_5 for CMSDASia  |
| Main.SudhirMalik - 02 July 2012 | General Review  |

%REVIEW% Main.MargueriteTonjes - 26 October 2017 %BR%
%REVIEW% Main.AdrianPerieanu - 15 July 2016%BR%
%REVIEW% Main.NitishDhingra - 03 October 2013%BR%
%RESPONSIBLE% Main.SudhirMalik%BR%
%ENDTWISTY%

Article text.

-- %USERSIG{SudhirMalik - 2017-12-15}%

---++ Comments

%COMMENT%
Topic revision: r1 - 2017-12-15 - sudhir_2emalik
CMSPublic