Data Structure (RAT::DS)

The event data structure is a tree of information about a particular event. Event producers create an instance of the data structure for each event, and processors can then operate on this structure, transforming it as desired. A single event is that which is generated when a macro calls /generator/beamOn; however, a processor is free to break this event into multiple sub-events.

The ratpac-two Data Structure

The ratpac-two data structure is defined in the src/ds directory and lists everything under the RAT::DS namespace. An instance of the data structure is defined in the RAT::DS::Root object. The data structure is tree-like, with each instance of RAT::DS::Root containing a list of RAT::DS::MC objects which contain the Monte Carlo truth information, and a list of RAT::DS::EV objects which contain the reconstructed event information (usually after going through a processor that simulates the detector response).

RAT::DS::MC

RAT::DS::EV

The ratpac-two ntuple structure

ratpac-two provides multiple output file formats, the simplest of which is called the “ntuple” output. The details of this output file format are described in outntuple. This output file format is generated by accessing the RAT::DS to fill flat ROOT TTrees, which are smaller and easier to work with than the full RAT::DS.