Module Parameter Setting

Datamembers of a module that are user-settable are called parameters. They can be identified by adding a '$' in the comment field immediately following the '//' of the datamember declaration:

Float_t fProbCut; //$ Probability cut

Parameters have to be of basic type ( Int_t, Short_t, Float_t, Long_t, UInt_t, Bool_t, Char_t*) or TString. Arrays and enum are currently not supported, but will likely be added in the future.

Parameters are identified automatically by the system and can be used in a number of ways:

• Parameters can be set and got very easily by using the Set and Get memberfunctions, so that you don't need to write explicit memberfunctions for them:

  root [0] TPhModuleContext *c = new TPhModuleContext;
  root [1] TPhObjectManager *o = new TPhObjectManager;
  root [2] c->SetObjectManager(o)
  root [3] TPhFindStraightTracksMod a("FindStraight", c)
  root [4] Float_t residual = 0.4;
  root [5] a.Set("fMaxResidual3", residual)
  root [6] Float_t copy_residual = 0;
  root [7] a.Get("fMaxResidual3", copy_residual)
  root [8] copy_residual
  (Float_t)4.00000005960464478e-01

• All parameters of a given module can be viewed and changed at the same time by a popup dialog box. The dialog box can be invoked by the module member SetParameters().

• Finally, the intention is that parameters from an analysis can be stored in an ASCII file for later retrieval or stored in the database. There are two memberfunctions for this purpose: Export(ofstream &) and Import(ifstream &) (see above example):

  root [10] ofstream f("my_analysis.txt")
  root [11] a.Export(f)
  root [12] .! cat my_analysis.txt
  Class: TPhFindStraightTracksMod
  Version: 1
  #ei Name of hit container (Input)
  TString fHitContainerName ""
  #eo Name of track container (Output)
  TString fTrackContainerName ""
  # Number of spectrometer layers for track finding
  Int_t fMaxLayer 4
  # Minimum number of hits on valid straight track
  Int_t fMinHits 3
  # Max hit residual in 3rd plane
  Float_t fMaxResidual3 0.4
  # Max hit residual in 4th plane
  Float_t fMaxResidual4 0.25
  

  However, this mechanism is not yet fully developed.