Go4 Event Classes

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DVEE-Seminar
GSIOnlineOfflineObjectOriented
Go4
The GO4 Event Classes
J. Adamczewski, M. Al-Turany, D. Bertini, H.G.
Essel
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Contents

• Go4 Software layers and architecture
• Go4 Analysis framework concepts
• Base classes for user event structures
• Getting data from MBS and .lmd
• Example Euroball
• Outlook User analysis in Go4 GUI
• Summary

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Go4 Package Layers
Go4 Framework
User Analysis
Go4 GUI
Go4TaskHandler
Qt Library
Go4ThreadManager
MBS
ROOT
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Go4 Framework concepts

• Based on standard ROOT system
• Online and Offline Framework
• Batch mode and interactive mode (GUI) may
  run same analysis
• Any user analysis may be adopted

Go4 provides interfaces (base classes) to
plug-in user event classes and analysis
Go4 implements all general services
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Event Base classes

• TGo4EventElement Event structure (input and
  output event)
• TGo4EventSource Fills event structure with
  data
• TGo4EventStore Stores event structure
• TGo4EventProcessor Converts input event into
  output event subclass of TGo4EventSource
• TGo4EventFactory Defines the user
  implementations of all the above at
  initialization

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Event service classes

• Interface to MBS
• TGo4MbsEvent, TGo4MbsSubEvent (format 10,1)
• TGo4MbsFile (read from .lmd)
• TGo4MbsEventServer
• TGo4MbsStream (connect to MBS)
• TGo4MbsTransport
• TGo4RevServ (connect to remote event server)
• Root File implementation
• TGo4FileSource, TGo4FileStore
• TGo4TreeSource, TGo4TreeStore

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Event classes diagram
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Example reading from MBS
Short_t idfield2 0,1 TGo4EventElement
event new TGo4MbsEvent(2, idfield,
1) TGo4EventSource input0 TGo4EventStore
output0 //////////// MBS LISTMODE
FILE input new TGo4MbsFile("/s/adamczew/ebtest.l
md") /////////// MBS TRANSPORT // input new
TGo4MbsTransport("r2f-2") /////////// MBS STREAM
// input new TGo4MbsStream("r2f-2")
/////////// MBS EVENTSERVER // input new
TGo4MbsEventServer("r2f-2") /////////// REMOTE
EVENT SERVER // input new TGo4RevServ("r2f-2")
output new TGo4FileStore("MbsEvents",1,5) even
t-gtSetEventSource(input) for(Int_t t0
tltmaxevents t) event-gtClear()
Int_t ermessevent-gtFill()
//.. do something with event here //
... output-gtStore(event) // write to root
file
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Analysis framework

• TGo4Analysis baseclass
• Analysis setup (chain of analysis steps)
• Object organization, dynamic histograms
• Implicit / explicit event loop
• Virtual methods to be defined in user analysis
  subclass
• TGo4AnalysisStep defines one stage of the
  analysis, implements event classes
• User designs own subclass of TGo4Analysis

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Analysis step
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Analysis framework

register objects
may use
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Example analysis Euroball
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Analysis in Go4 GUI

• TGo4AnalysisClient
• runs analysis in multithreading mode
• connects to a (remote) process which runs the
  GUI
• TGo4GUI
• non-blocking, multithreading
• launches analysis client as remote process
• Based on Qt graphics library and ROOT

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Analysis in Go4 GUI
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Analysis in Go4 GUI
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Using Go4 components
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Summary

• Go4 is ready for use
• Event classes already under test by gt5
  experiments (any feedback is welcome!)
• Go4 components offer different levels of
  integration
• Go4 is flexible external analysis (Hades)
  can run in multithreaded framework
• Powerful Qt-GUI exists, is being improved
• First official release of Go4 in spring 2002!