1. J. Adamczewski, M. Al-Turany, D. Bertini, H.G. Essel
DVEE-Seminar
GSI Online Offline Object Oriented
Go4
The GO4 Event Classes
J. Adamczewski, M. Al-Turany, D. Bertini, H.G. Essel
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2. 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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3. Go4 Package Layers MBS ROOT Go4 Framework User Analysis Go4 GUI
Go4TaskHandler
Go4 Analysis
Qt Library
Go4 Event
Go4ThreadManager
Interface
MBS
ROOT
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4. 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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5. 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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6. } Event service classes Interface to MBS: Root File implementation:
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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7. Event classes diagram User classes TGo4EventSource TGo4EventElement
TGo4EventStore
TGo4EventProcessor
TGo4FileSource
TGo4FileStore
User classes
TUserEventProcessor
TGo4MbsSource
TGo4MbsEvent
TUserEvent
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8. Example: reading from MBS
Short_t idfield[2]= {0,1};
TGo4EventElement* event = new TGo4MbsEvent(2, idfield, 1);
TGo4EventSource* input=0;
TGo4EventStore* output=0;
//////////// MBS LISTMODE FILE
input= new TGo4MbsFile("/s/adamczew/ebtest.lmd");
/////////// 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);
event->SetEventSource(input);
for(Int_t t=0; t<maxevents; ++t) {
event->Clear();
Int_t ermess=event->Fill();
//.. do something with event here
// ...
output->Store(event); // write to root file }
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9. 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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10. Analysis step Previous Step TGo4EventFactory TGo4FileSource
TUserEvent1
TUserEventFactory_1
CreateEventSource()
CreateInputEvent()
CreateEventProcessor()
CreateOutputEvent()
CreateEventStore()
TUserEventProcessor
TUserEvent2
Next Step
TGo4FileStore
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11. Analysis framework * TGo4Analysis TGo4AnalysisStep TGo4EventFactory
register objects
TUserAnalysis
TUserAnalysis()
~TUserAnalysis()
UserEventFunc()
UserPreLoop()
UserPostLoop()
TUserEventFactory_1
may use
TUserEventFactory_n
TExternalAnalysis
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12. Example analysis: Euroball
Step1
Step2
event
processors
elements
sources
analysis
framework
event factories
store
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13. 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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14. Analysis in Go4 GUI
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15. Analysis in Go4 GUI
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16. connect analysis client
Using Go4 components
connect analysis client
Go4Analysis
Go4GUI
subclassing
TGo4Analysis
subclassing
TGo4Analysis,
register objects
(TTree, TH1)
Go4Analysis
Steps
user event
factories
Go4Events
user event
subclasses
other analysis
framework
(HADES)
Go4Event I/O
(MBS, .lmd)
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17. Summary Go4 is ready for use
Event classes already under test by >5 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!
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