Analysis Suite

Executables

Executable	Description
rebdsim	Main analysis tool. Reads histogram definition file.
rebdsimCombine	Combines output from multiple runs of rebdsim
rebdsimHistoMerge	Loops over events and calculates mean of histograms already store in output only. A quick way to get a summary of data.
rebdsimOptics	Calculates the optics only from a BDSIM ROOT file
rebdsimOrbit	Extracts the primary particle hit in each sampler for a given event
edbdsim	Event display

Source Libraries

The classes stored in the output are compiled into the BDSIM library, however, they are also copied into a separate library called libBdsimRootEvent without any Geant4 types of linkages. These classes are bdsim/include/BDSOutputROOTEvent*.

A series of classes for loading the output in the structure as it is in the output files are included in bdsim/analysis. These are compiled into a library called librebdsim.

The user must load both libraries to fully inspect the data.

Note

No Geant4 types are exposed to the output as this would increase the complexity of the interface with ROOT and ROOT’s inspection of the types for reflection.

Dynamic Loading

Loading all of the data at once results in slow performance and is often unnecessary. For the event tree where the majority of the data is stored, it is advantageous to only load the ‘branches’ required for a particular analysis. Turning off branches means that when GetEntry(n) is called on the tree, nothing is copied out of the file onto the local objects. We therefore turn ‘on’ the branches we need for a particular analysis.

The analysis tool rebdsim works out the branches required when parsing histogram definitions and these are stored in a map of branch names for each tree. The DataLoader class takes this as an optional argument and turns on the appropriate branches.

The default arguments for the DataLoader class are such that all data is loaded. It is non-trivial and requires a lot of typing to define the map necessary for efficient loading, which hinders a user when inspecting data interactively. Therefore, all data is on when loading interactively.

Interactive Usage

The code used for analysis must be maintained in such a way that is both useful for the compiled analysis tools, but also simple to use interactively.