Cosmetics

advanced/EmbedJulia/G4example.cpp

@@ -153,15 +153,15 @@ int main(int, char**)
     int nthreads = 0; // Default number of threads
     if (getenv("G4NUMTHREADS")) nthreads = atoi(getenv("G4NUMTHREADS"));
 
-    //--- Required to setup the Julia context
+    //--- Required to setup the Julia context------------------------------------------------------
     jl_init();
         /* run Julia commands */
     jl_eval_string("include(\"MyCode.jl\")");
     if (jl_exception_occurred()) {
         std::cout << "=====> " << jl_typeof_str(jl_exception_occurred()) << std::endl;
     }
 
-    //---Construct the default run manager
+    //---Construct the default run manager (taking into account the number of threads)-------------
     G4RunManager* runManager;
     if (nthreads > 0) { 
         runManager = G4RunManagerFactory::CreateRunManager(G4RunManagerType::MT);
@@ -171,10 +171,7 @@ int main(int, char**)
         runManager = G4RunManagerFactory::CreateRunManager(G4RunManagerType::Serial);
     }
 
-    //---Set mandatory initialization classes
-
-
-
+    //---Set mandatory initialization classes------------------------------------------------------
     // Detector construction
     runManager->SetUserInitialization(new DetectorConstruction());
 
@@ -197,12 +194,12 @@ int main(int, char**)
     UImanager->ApplyCommand("/gun/energy 100 MeV");
 
     // Start a run (we need to enter GC safe region here because the worker threads 
-    // will enter a wait state waiting for workers to finish and can block GC
+    // will enter a wait state while waiting for workers to finish and this can block GC
     auto state = jl_gc_safe_enter(jl_current_task->ptls);
     runManager->BeamOn(100000);
     jl_gc_safe_leave(jl_current_task->ptls, state);
 
-    // Job termination
+    // Job termination---------------------------------------------------------------------------
     delete runManager;
 
     // strongly recommended: notify Julia that the program is about to terminate. 

advanced/EmbedJulia/MyCode.jl

@@ -7,6 +7,8 @@ using Parameters
 println("=====> Loading MyCode.jl")
 
 #---Simulation data struct-------------------------------------------------------------------------
+# define a mutable struct to store the simulation data (counters, hitograms, etc.)
+# make N+1 instances of this struct, where N is the number of threads
 @with_kw mutable struct MyData
     edep = 0.0
     edepHist = H1D("Event total Edep distribution", 100, 0., 110.)
@@ -46,12 +48,11 @@ function begin_of_run_action(run)
 end
 
 function end_of_run_action(run)
-    if G4Threading!G4GetThreadId() < 0
+    if G4Threading!G4GetThreadId() < 0   # only for the master thread
         println("=====> End of run")
         data = simdata[1]
-        ##---This is the master thread, so we need to add all the simulation results-----------------
         for d in simdata[2:end]
-            add!(data, d)
+            add!(data, d)                # merge all thread data to the master data
         end
         h = data.edepHist
         img = plot(h.hist, title=h.title)