1. The Go4 eventloop framework: analysis steps
GSI Online Offline Object Oriented
The Go4 eventloop framework: analysis steps
J. Adamczewski, M. Al-Turany, D. Bertini, H.G.Essel, S.Linev
ROOT 2002
15-Oct-2002
J. Adamczewski -

2. J. Adamczewski - http://go4.gsi.de
Contents
Go4 analysis framework concepts
Event base classes
Analysis steps
Eventloop actions
Example of user analysis
GUI control of analysis
15-Oct-2002
J. Adamczewski -

3. J. Adamczewski - http://go4.gsi.de
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
15-Oct-2002
J. Adamczewski -

4. J. Adamczewski - http://go4.gsi.de
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
15-Oct-2002
J. Adamczewski -

5. J. Adamczewski - http://go4.gsi.de
Implemented Services
GSI standard DAQ (Mbs)
Complex event structures „toolbox“: TGo4CompositeEvent, ... < see Denis Bertini‘s talk
Root I/O :
TGo4FileSource, TGo4FileStore : wraps 1 TTree in 1 TFile
TGo4BackStore : 1 TTree in memory only ( <- online TTree::Draw() )
both can handle TGo4CompositeEvent
15-Oct-2002
J. Adamczewski -

6. J. Adamczewski - http://go4.gsi.de
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
15-Oct-2002
J. Adamczewski -

7. J. Adamczewski - http://go4.gsi.de
Analysis Step
Previous Step
TGo4EventFactory
TGo4FileSource
TGo4EventServerFactory
CreateEventSource()
CreateEventStore()
TUserEvent1
TUserEventProcessor
TUserEventFactory_1
CreateInputEvent()
CreateEventProcessor()
CreateOutputEvent()
TUserEvent2
Next Step
TGo4FileStore
15-Oct-2002
J. Adamczewski -

8. J. Adamczewski - http://go4.gsi.de
Analysis Framework
TGo4Analysis
TGo4AnalysisStep *
TGo4EventFactory
register objects
TUserAnalysis
TUserAnalysis()
~TUserAnalysis()
UserEventFunc()
UserPreLoop()
UserPostLoop()
TUserEventFactory_1
TUserEventFactory_n
15-Oct-2002
J. Adamczewski -

9. Eventloop Actions UserPreLoop Step1 ProcessAnalysisSteps StepN
fill event
get event
store event
histograming
Step1
ProcessAnalysisSteps
init objects
StepN
UserEventFunc
? other Analysis
histograming
HYDRA
ProcessDynamicList
TTree registry
UserPostLoop
online TTree::Draw()
reset objects
15-Oct-2002
J. Adamczewski -

10. Example Analysis: Euroball
Step1
Step2
event
processors
elements
sources
analysis
framework
event factories
15-Oct-2002
J. Adamczewski -

11. Analysis Setup Control
15-Oct-2002
J. Adamczewski -

12. Using Go4 Components Go4Analysis Go4GUI Go4Analysis Steps Go4Events
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)
15-Oct-2002
J. Adamczewski -

13. J. Adamczewski - http://go4.gsi.de
Summary
Go4 Analysis framework is flexible
Event base classes define interface
Framework services + user subclasses
Analysis steps: common set up (gui control)
uses Root data management / object streamer
Go4 Version 2.0 ready
15-Oct-2002
J. Adamczewski -