How to execute GRAS

In order to run GRAS you have to provide the $ gras command at the command line.

The gras executable can accept the following syntax:

$ gras [optional flags] <macro_file> <PhysicsListName>

where:

  • <macro_file>: a macro file to execute (optional). Note: In case of multiple macro files provided (see -m flag below) this will be executed last.

  • <PhysicsListName>: a physics list name to be used during the simulation (optional)

  • [optional flags]: one or a combination of the following:

  • -p PhysicsListName: additional way of providing a Physics list name

  • -g GDMLGeometryFile: set a GDMLfile as the geometry of the simulation

  • -u UISession: select the UI type between the available ones (e.g “qt”, “tcsh”, …). Note: Effective only for interactive simulations.

  • -t NumberOfThreads:specify the number of threads for the simulation. Note: Effective only for MT simulations.

  • -m <macro_file>: additional way ofspecifying a macro file. If given multiple times the macro files will be executed in order of appearance.

A GRAS simulation can be run either in

  • batch mode, by reading macro file/files with UI commands

  • interactive mode, by providing UI commands at the command line (no macro file provided at the command line)

In the case GRAS is compiled with MT support the default execution of the simulation will be in MT mode with NumberOfCores - 1 threads. In case a sequential simulation is desired even if Geant4 and GRAS are compiled with MT support the environment variable G4RUN_MANAGER_TYPE can be set to Serial (G4RunManager ).

GRAS/trunk/r2242