-- AugustinasS - 20-Sep-2010 =======Bookmarkai ir pastabos=======
Oct. 18, 2010



Oct. 11, 2010

FW Lite = ROOT + CMS DataFormats + helper classes.FW Lite (pronounced "framework-light") is just that -- a ROOT session with CMS data format libraries loaded. 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 FW Lite and the Full Framework.

5 pratimas:How to configure your PAT Tuple

edmDumpEventContent ishmeta kontenta.edmConfigEditor grafine konfiguracija.

esme tame, kad su ConfigEditoriu ,galima patogiai modifikuoti standartinius konfigus, jei tixliai nzn ka darai, nros su vimu yra daug greichiau.


* Learn what the problem of internal references is within the EDM.

* Learn how PAT solves this situation.

* Learn how to embed extra information into a pat::Candidate.

In our example while producing a pat::Tuple, one may want to retain the CaloTowers of which the CaloJets were produced for later use, while dropping all the others. To allow for this PAT has introduced the concept of embedding

edmEventSize -v patTuple.root <-- rinkinio dydiz

The first number of the output indicates the uncompressed event size while the second number shows the event size at the current zip compression level used within the EDM. The second number is the important one to check what disc space will physically be needed per event to store this collection. Using the PAT default, cleanPatJets and a collection of calo towers clustered inside the pat::Jets are kept in the event. Together they make up about 11kB per event for the default MC sample (ttbar)

The pat::Jet collection plus the whole CaloTower collection (29kB per event) is bigger than the pat::Jet collection with embedded calo towers (11kB per event), since only towers clustered in the jets are stored in that case.


* Learn what the problem of object double counting in the reconstruction is.

* Learn how PAT supports object disambiguation.

* Learn how to configure and how to make use of the object disambiguation support of PAT.

Electrons usually end up in the calorimeters and deposit all their energy there, if they have enough transverse momentum. The clustering algorithms run over the calorimeter objects and create clusters and clusters of clusters called super clusters, which is one of the elements of the electron reconstruction at CMS. First problems occur when a CaloTower is created as the seed of a CaloJet, including the energy deposits of the electron:

* For the reconstructed jet the purely electromagnetic energy of the electron is reconstructed at a wrong energy scale. * The energy of the electron in the detector is reconstructed twice: once as an electron and once as a jet. * Isolated electrons (which are enriched in many event classes) will be reconstructed as jets and might dilute the interpretation of the event.

For the latter case you could e.g. think of the interpretation of an event being W+jet or ttbar or even ttbar+jet. We will not cover the first item here as it is an issue of jet energy scale calibration. This tutorial will cover the topic how PAT supports object disambiguation, which means to resolve the double reconstruction of energy in the detector.

tracker isolated electrons (labelled as tkIsoElectrons).

The histogram, shows the distribution of the electromagnetic energy fraction of the leading jets with pt>20 GeV. The small peak around 1 originates from jets that deposited all of their energy in the ECAL. As we are using a ttbar sample as input many of these jets originate from isolated electrons that belong to leptonically decaying W bosons.


* Learn about the support of any kind of matching in the Analysis Tools (AT) Group. * Learn how PAT exploits these matching tools for Monte Carlo truth matching. * Learn how to configure Monte Carlo truth matching in PAT and how to access it.

You can use the python interpreter to find out which member function the class object of cms has

cmsenv python -i import ParameterSet.Config as cms dir(cms) dir(cms.Sequence) help(cms.Sequence.replace) q

shita dar paishziuret bishki balalaika


* Learn about the support of matching in the PhysicsTools. * Learn how PAT supports these matching tools. * Learn how to configure Monte Carlo truth matching in PAT and how to access it.

Triggering any interesting event and storing this information to the granularity level accessible at CMS is a complex and difficult task. The CMS trigger is nearly a parallel world to the world of RECO objects. To access trigger information within the EDM can be an extremely challenging task for a normal user. PAT provides you with an easy entry point to access trigger information via the pat::TriggerEvent. Nevertheless the amount accessible information via the PAT TriggerEvent can still be enormous and not all of this information you need. PAT provides sensible default configurations but not all use cases are covered. So configuring the amount of trigger information that will be written to your pat::Tuple to what you really need is not only beneficial because of the size of your pat::Tuple but might even be necessary. It is therefore important to have at least a basic understanding of how the PAT TriggerEvent is configured and produced. The following examples provide a gentle introduction on this subject. As you will see the PAT TriggerEvent is the central access door to all information related to CMS L1 and HLT triggers. By the end of these exercises you should be able to answer the following question: what is the PAT TriggerEvent collection and how do I get access to trigger information from there?

* removeMCMatching: MC matching is removed from the patDefaultSequence, you remember that PAT adds MC information per default and for running on data it needs to be removed. * addPfMET: Particle Flow MET is added. * switchJECSet: The jet energy corrections are switched to the most up to date set of correction factors ('Spring10'). * addJetCollection: The AK5 particle flow jet collection is added to the event content.

Enabling trigger information in your pat::Tuple thus needs a few lines only. Have a look at:

less $CMSSW_RELEASE_BASE/src/PhysicsTools/PatAlgos/python/tools/trigTools.py

Oct. 06, 2010

pahziuret kiek liko vietos fs lq

: We will next run the FWLiteAnalyzer example. You would do an analysis within FWLite, when performing smaller studies on the basis of (compiled) root macros.

We use the command rehash here after compiling to get the correct executable after the tab completion. Instead of rehash you may also just retype cmsenv in your working directory, which will have the same effect.

In FWLite there is no other interaction with the EDM event content but reading. You can view FWLite executables as a safer (and more convenient) way to write compiled interactive root macros

cpp analizatoriu pradmenys plius fwlite intro https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookPATAccessExercise

Oct. 05, 2010

esminis klausimas kaip naudotis necerno gridu?

grid-proxy-init parodo teisingai nfo, ale reikalauja passfraze(??)

voms-proxy-init -voms cms (??)

pasiknisti dar po konfigus

source /afs/cern.ch/cms/LCG/LCG-2/UI/cms_ui_env.csh <-shitoje direktorijoje ir yra inicializacijos skriptai

pirmos dienos trechias pratimas su gridu https://twiki.cern.ch/twiki/bin/view/CMS/WorkBookCRABTutorial#SetUpEnv

krabo configai ir kaip juo naudotis https://twiki.cern.ch/twiki/bin/view/CMS/WorkBookCRABTutorial#SetUpCRABEnv

krabo faq https://twiki.cern.ch/twiki/bin/view/CMS/SWGuideCrabFaq

Sept. 28, 2010

cms frameworko intro https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookCMSSWFramework

kodo generatoriai https://twiki.cern.ch/twiki/bin/viewauth/CMS/SWGuideSkeletonCodeGenerator

Sept. 27, 2010

BuildFiles https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookBuildFilesIntro

MessageLogger https://twiki.cern.ch/twiki/bin/viewauth/CMS/SWGuideMessageLogger

FWLite macrosai https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookFWLiteExamples

pitono configu manualas https://twiki.cern.ch/twiki/bin/viewauth/CMS/SWGuideAboutPythonConfigFile

Sept. 26, 2010


The main properties that distinguish a tuple from, for example, a set are that it can contain an object more than once; the objects appear in a certain order; it has finite size.

in database theory, the relational model uses a definition similar with tuples as functions above, but each tuple element is identified by a distinct name, called an attribute, instead of a number. A tuple in the relational model is formally defined as a finite function that maps attributes to values. Its purpose is the same as in mathematics, that is, to indicate that an object consists of certain components, but the components are identified by name instead of position,

Sept. 23, 2010

Kas yra Selectoriai ? https://twiki.cern.ch/twiki/bin/viewauth/CMS/SWGuidePATSelectors

Sept. 21, 2010


stand-alone executables edmDumpEventContent (which dumps a list of the collections present in the file to the terminal), and edmBrowser (which has a nice graphical interface).

The CMS files contain embedded information sufficient to tell the history of the objects in the file. This information is called provenance, and is crucial for the analysis, as it allows the user to establish with certainty what kind of operations (corrections, calibrations, algorithms) were performed on the data present in the file. The stand-alone executable edmProvDump prints the provenance to the screen.

1. cmsRun copyPickMerge_cfg.py naudojamas duomenu kopijavimui i localu kompa

1. edmCopyPickMerge keliu failu sujungimui

1. edmPickEvents.py spec. ivykiu isrinkimui

1. Fireworks vizualizacijai. (nebutinas 3D!)


Yra įmanoma naudoti python vieton CINT Root aplinkoje.

https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookBasicROOT Root pradzhiamokslis, kaip elgtis su histogramom, kaip rashyti skriptus ir etc. https://twiki.cern.ch/twiki/bin/viewauth/CMS/WorkBookFWLite FWLite stuffas ROOT sajte yra neblogas dokumentacija kaip elgtis su makrosais, pachiu rootu ir etc.

Sept. 20, 2010

Tekstas apie TWiki formatavimÄ….


Edit | Attach | Watch | Print version | History: r13 < r12 < r11 < r10 < r9 | Backlinks | Raw View | WYSIWYG | More topic actions
Topic revision: r13 - 2010-10-18 - AugustinasS
    • Cern Search Icon Cern Search
    • TWiki Search Icon TWiki Search
    • Google Search Icon Google Search

    Main All webs login

This site is powered by the TWiki collaboration platform Powered by PerlCopyright &© 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback