diff --git a/FDTD/operator.cpp b/FDTD/operator.cpp
index 08906d9..514f571 100644
--- a/FDTD/operator.cpp
+++ b/FDTD/operator.cpp
@@ -139,9 +139,9 @@ struct Operator::Grid_Path Operator::FindPath(double start[], double stop[])
 	double meshStart[] = {discLines[0][uiStart[0]], discLines[1][uiStart[1]], discLines[2][uiStart[2]]};
 	double meshStop[] = {discLines[0][uiStop[0]], discLines[1][uiStop[1]], discLines[2][uiStop[2]]};
 
-	double foot,dist,minFoot,minDist;
-	int minDir;
 	bool UpDir;
+	double foot=0,dist=0,minFoot=0,minDist=0;
+	int minDir=0;
 	unsigned int minPos[3];
 	double startFoot,stopFoot,currFoot;
 	Point_Line_Distance(meshStart,start,stop,startFoot,dist);
@@ -158,7 +158,7 @@ struct Operator::Grid_Path Operator::FindPath(double start[], double stop[])
 			P[0] = discLines[0][currPos[0]];
 			P[1] = discLines[1][currPos[1]];
 			P[2] = discLines[2][currPos[2]];
-			if ((currPos[n]-1)>=0)
+			if (((int)currPos[n]-1)>=0)
 			{
 				P[n] = discLines[n][currPos[n]-1];
 				Point_Line_Distance(P,start,stop,foot,dist);
@@ -725,13 +725,13 @@ bool Operator::CalcEFieldExcitation()
 	double delta[3];
 	double amp=0;
 
-	for (pos[2]=0;pos[2]<numLines[2];++pos[2])
+	for (pos[2]=0;pos[2]<(int)numLines[2];++pos[2])
 	{
 		delta[2]=fabs(MainOp->GetIndexDelta(2,pos[2]));
-		for (pos[1]=0;pos[1]<numLines[1];++pos[1])
+		for (pos[1]=0;pos[1]<(int)numLines[1];++pos[1])
 		{
 			delta[1]=fabs(MainOp->GetIndexDelta(1,pos[1]));
-			for (pos[0]=0;pos[0]<numLines[0];++pos[0])
+			for (pos[0]=0;pos[0]<(int)numLines[0];++pos[0])
 			{
 				delta[0]=fabs(MainOp->GetIndexDelta(0,pos[0]));
 				coord[0] = discLines[0][pos[0]];
@@ -748,7 +748,7 @@ bool Operator::CalcEFieldExcitation()
 						CSPropElectrode* elec = prop->ToElectrode();
 						if (elec!=NULL)
 						{
-							if ((elec->GetActiveDir(n)) && (pos[n]<numLines[n]-1))
+							if ((elec->GetActiveDir(n)) && (pos[n]<(int)numLines[n]-1))
 							{
 								amp = elec->GetWeightedExcitation(n,coord)*delta[n]*gridDelta;
 								if (amp!=0)
@@ -865,5 +865,7 @@ bool Operator::CalcPEC()
 			}
 		}
 	}
+
+	return true;
 }
 
diff --git a/FDTD/processcurrent.cpp b/FDTD/processcurrent.cpp
index 381d567..66c23a0 100644
--- a/FDTD/processcurrent.cpp
+++ b/FDTD/processcurrent.cpp
@@ -65,22 +65,22 @@ int ProcessCurrent::Process()
 	}
 
 	//x-current
-	for (int i=start[0];i<stop[0];++i)
+	for (unsigned int i=start[0];i<stop[0];++i)
 		current+=Eng->curr[0][i][start[1]][start[2]];
 	//y-current
-	for (int i=start[1];i<stop[1];++i)
+	for (unsigned int i=start[1];i<stop[1];++i)
 		current+=Eng->curr[1][stop[0]][i][start[2]];
 	//z-current
-	for (int i=start[2];i<stop[2];++i)
+	for (unsigned int i=start[2];i<stop[2];++i)
 		current+=Eng->curr[2][stop[0]][stop[1]][i];
 	//x-current
-	for (int i=start[0];i<stop[0];++i)
+	for (unsigned int i=start[0];i<stop[0];++i)
 		current-=Eng->curr[0][i][stop[1]][stop[2]];
 	//y-current
-	for (int i=start[1];i<stop[1];++i)
+	for (unsigned int i=start[1];i<stop[1];++i)
 		current-=Eng->curr[1][start[0]][i][stop[2]];
 	//z-current
-	for (int i=start[2];i<stop[2];++i)
+	for (unsigned int i=start[2];i<stop[2];++i)
 		current-=Eng->curr[2][start[0]][start[1]][i];
 
 //	cerr << "ts: " << Eng->numTS << " i: " << current << endl;
diff --git a/FDTD/processfields.cpp b/FDTD/processfields.cpp
index 49214c7..3d538c6 100644
--- a/FDTD/processfields.cpp
+++ b/FDTD/processfields.cpp
@@ -193,6 +193,7 @@ bool ProcessFields::DumpMultiVectorArray2VTK(ofstream &file, string names[], FDT
 		WriteVTKVectorArray(file, names[n], array[n], numLines);
 		file << endl;
 	}
+	return true;
 }
 
 void ProcessFields::WriteVTKScalarArray(ofstream &file, string name, FDTD_FLOAT*** array, unsigned int* numLines)
@@ -220,16 +221,18 @@ bool ProcessFields::DumpScalarArray2VTK(ofstream &file, string name, FDTD_FLOAT*
 {
 	WriteVTKHeader(file, discLines, numLines);
 	WriteVTKScalarArray(file, name, array, numLines);
+	return true;
 }
 
 bool ProcessFields::DumpMultiScalarArray2VTK(ofstream &file, string names[], FDTD_FLOAT*** array[], unsigned int numFields, double** discLines, unsigned int* numLines)
 {
 	WriteVTKHeader(file, discLines, numLines);
-	for (int n=0;n<numFields;++n)
+	for (unsigned int n=0;n<numFields;++n)
 	{
 		WriteVTKScalarArray(file, names[n], array[n], numLines);
 		file << endl;
 	}
+	return true;
 }