diff --git a/Common/LuaBindings.cpp b/Common/LuaBindings.cpp
index c829911287b68dc3804c062e7730797f6db033df..c75451330afcf186c39bd641130a4928abef311d 100644
--- a/Common/LuaBindings.cpp
+++ b/Common/LuaBindings.cpp
@@ -123,7 +123,8 @@ void binding::interactiveSession(){
       add_history(expansion);
       report_errors(L, luaL_dostring(L, expansion));
     }
-    free(expansion);
+    if(expansion)
+      free(expansion);
   }
   clear_history();
   #else
diff --git a/Solver/TESTCASES/WavePulse.lua b/Solver/TESTCASES/WavePulse.lua
index 982cfeb34db6ac4300a7e8dc7876a6a59ef67708..a9dee53840444b3772fe02d0bb73004a3ddcf57e 100644
--- a/Solver/TESTCASES/WavePulse.lua
+++ b/Solver/TESTCASES/WavePulse.lua
@@ -1,5 +1,3 @@
-
-
 --[[ 
      Function for initial conditions
 --]]
@@ -55,9 +53,9 @@ print('DT = ',dt)
 for i=1,N do
 --    norm = DG:multirateRK43(dt)
     norm = DG:RK44(dt)
-    print('*** ITER ***',i,norm)
-    if (i % 10 == 0) then 
-       DG:exportSolution(string.format("output/solution-%04d", i)) 
+    if (i % 100 == 0) then 
+      print('*** ITER ***',i,norm)
+      DG:exportSolution(string.format("output/solution-%04d", i)) 
     end
 end
 
diff --git a/Solver/dgGroupOfElements.cpp b/Solver/dgGroupOfElements.cpp
index f93e120e72eb265980e920562eb2acbb7e88e7f0..42d9044416a2390891409344eab5c6a556aad32f 100644
--- a/Solver/dgGroupOfElements.cpp
+++ b/Solver/dgGroupOfElements.cpp
@@ -88,6 +88,7 @@ dgGroupOfElements::dgGroupOfElements(const std::vector<MElement*> &e, int polyOr
         for (int l=0;l<nbPsi;l++) { 
           imass(k,l) += f[k]*f[l]*weight*detjac;
         }
+        // (iQP*3+iXYZ , iFace*NPsi+iPsi)
         (*_dPsiDx)(j*3  ,i*nbPsi+k) = g[k][0]*ijac[0][0]+g[k][1]*ijac[0][1]+g[k][2]*ijac[0][2];
         (*_dPsiDx)(j*3+1,i*nbPsi+k) = g[k][0]*ijac[1][0]+g[k][1]*ijac[1][1]+g[k][2]*ijac[1][2];
         (*_dPsiDx)(j*3+2,i*nbPsi+k) = g[k][0]*ijac[2][0]+g[k][1]*ijac[2][1]+g[k][2]*ijac[2][2];
@@ -266,7 +267,7 @@ void dgGroupOfFaces::init(int pOrder) {
 	getElementLeft(i)->getJacobian ((intLeft)(j,0), (intLeft)(j,1), (intLeft)(j,2), jac);
 	inv3x3(jac,ijac);
 	//compute dPsiLeftDxOnQP
-	//(iPsi*3+iXYZ,iQP+iFace*NQP);
+  // (iQP*3+iXYZ , iFace*NPsi+iPsi)
 	int nPsi = _fsLeft->coefficients.size1();
 	for (int iPsi=0; iPsi< nPsi; iPsi++) {
 	  (*_dPsiLeftDxOnQP)(j*3  ,i*nPsi+iPsi) = g[iPsi][0]*ijac[0][0]+g[iPsi][1]*ijac[0][1]+g[iPsi][2]*ijac[0][2];
diff --git a/Solver/dgSystemOfEquations.cpp b/Solver/dgSystemOfEquations.cpp
index a4d074086caf3e53c7e922f415c6e500e3b018ee..8616b5bf532e10f64b007623d35caa1405a47ea4 100644
--- a/Solver/dgSystemOfEquations.cpp
+++ b/Solver/dgSystemOfEquations.cpp
@@ -43,7 +43,7 @@ static dgSystemOfEquations *myConstructorPtr(GModel* gm){
   return new dgSystemOfEquations(gm);
 }
 
-void dgSystemOfEquations::registerBindings(binding *b){
+void dgSystemOfEquations::registerBindings(binding *b) {
   classBinding *cb = b->addClass<dgSystemOfEquations>("dgSystemOfEquations");
   cb->setDescription("a class to rule them all :-) -- bad description, this class will be removed anyway");
   cb->setConstructor<dgSystemOfEquations,GModel*>();