Managing of Parameters and Conditions

Parameters and Conditions have to be declared in the file TXXXProc.h. While Conditions are handled in the same way as histograms (definition in TXXXProc.cxx), Parameters have their own class where they are managed: TXXXParam.


That means that the declarations of the parameters in TXXXProc.h was only the declaration of the class. For using specific parameters on has to declare the members in the TXXXParam.h and initialise them and define the corresponding methods in the file TXXXParam.cxx:

  • The method TXXXParam initialises the parameters
  • The method PrintParameter prints them
  • and in the method UpdateFrom the parameteres are restored from the autosave file

The restoration from the autosave file is important when you want to change parameters during and after the analysis. The new parameters are stored in the autosave file and can be used without compiling the code again.

One can look at the code in the TXXXProc.cxx to see how the parameteres are handled as normal factors or conditions.


Conditions are in the same way managed as histograms. One can again look in the corresponding files to see how it is done and use them as a template.

Conditions are applied in the following way:

condition -> Test(entry)

Here the method Test checks if the value "entry" is inside the limits of the condition. This command returns true or false.


When one did an analysis (e.g. in batch mode) one can open the autosave file with the Go4 GUI. Here on the left side one can see in the folders Conditions and Parameters. Double click on the condition or the parameter and the Condition or the Parameter Editor will show up. One can now change the values by entering new numbers and in case of the conditions via dragging the limits. Now one has to save the new entries:

  • save if one wants to store the values in the autosave file or
  • send them to analysis if an analysis via GUI is running (also online analysis)

Now one can run the analysis again (batch mode) or continue the running analysis (GUI) using the new  parameters / conditions without re-compiling.