diff --git a/Version_Max_07_05_2018_CMake/src/LinearFunctionBlock.cpp b/Version_Max_07_05_2018_CMake/src/LinearFunctionBlock.cpp
index ab42a67..05dca08 100755
--- a/Version_Max_07_05_2018_CMake/src/LinearFunctionBlock.cpp
+++ b/Version_Max_07_05_2018_CMake/src/LinearFunctionBlock.cpp
@@ -1,106 +1,106 @@
 #include "LinearFunctionBlock.h"
-
-//#define PRINT
+#include <limits>
 
 LinearFunctionBlock::LinearFunctionBlock() {
 #ifdef PRINT
 	printf(" > Linear Function Block created\n");
 #endif // PRINT
 }
 
 LinearFunctionBlock::LinearFunctionBlock(char* name) : Module(name) {
 #ifdef PRINT
 	printf(" > %s (id:%u) created\n", name, id);
 #endif // PRINT
 }
 
 LinearFunctionBlock::~LinearFunctionBlock() {
 	LinearFunction* cur_Linear_Function;
 	unsigned int index_cur_Linear_Function;
 	unsigned int size_vec_Linear_Functions = vLinearFunctions.size();
 	for(index_cur_Linear_Function = 0; index_cur_Linear_Function < size_vec_Linear_Functions; index_cur_Linear_Function++){
 		cur_Linear_Function = vLinearFunctions[index_cur_Linear_Function];
 		delete cur_Linear_Function;
 	}
 	vLinearFunctions.clear();
 }
 
 //NOTE: for this time being, linear functions have to be filled beginning from lowest x value 
 bool LinearFunctionBlock::addLinearFunction(LinearFunction *linearFunction) {
 	if (vLinearFunctions.empty()) {
 		//printf("empty\n");
 		if (!(linearFunction->getDomain()->lowerBoundaryExist())) {
 			vLinearFunctions.push_back(linearFunction);
 #ifdef PRINT
 			printf(" - added function\n");
 #endif // PRINT
 			return true;
 		}
 	}
 	else
 	{
 		//printf("nicht empty\n");
 		if (vLinearFunctions.back()->getDomain()->upperBoundaryExist() && linearFunction->getDomain()->lowerBoundaryExist()) {
 			//printf("last function ub = %f, new function lb = %f\n", lLinearFunctions.back()->getDomain()->getUpperBoundary(), linearFunction->getDomain()->getLowerBoundary());
 			if (vLinearFunctions.back()->getDomain()->getUpperBoundary() == linearFunction->getDomain()->getLowerBoundary()) {
 				vLinearFunctions.push_back(linearFunction);
 #ifdef PRINT
 				printf(" - added function\n");
 #endif // PRINT
 				return true;
 			}
 		}
 	}
 
 	printf(" - couldn't add function\n");
 	return false;
 }
 
 //NOTE: Specific Function for CAH Project (DATE18) 
 void LinearFunctionBlock::changeFunctionBlockIncr(float newBoundary) {
 	vLinearFunctions[1]->setDomain(true, (float)0, true, newBoundary);
 	vLinearFunctions[1]->setKandD((float)0, (float)0, newBoundary, (float)1);
 	vLinearFunctions[2]->setDomain(true, newBoundary, false);
 }
 
 void LinearFunctionBlock::changeFunctionBlockDecr(float newBoundary) {
 	vLinearFunctions[1]->setDomain(true, (float)0, true, newBoundary);
 	vLinearFunctions[1]->setKandD((float)0, (float)1, newBoundary, (float)0);
 	vLinearFunctions[2]->setDomain(true, newBoundary, false);
 }
 
 
 
 //TODO: jump discontinuity -> user must have the probability to set the value there
 float LinearFunctionBlock::getY(float x) {	
 	for (auto &linearFunction : vLinearFunctions) {
 		if (linearFunction->getDomain()->lowerBoundaryExist() && linearFunction->getDomain()->upperBoundaryExist()) {
 			if (x >= linearFunction->getDomain()->getLowerBoundary() && x <= linearFunction->getDomain()->getUpperBoundary()) {
 				return linearFunction->getY(x);
 			}
 		}
 		else if (linearFunction->getDomain()->lowerBoundaryExist()) {
 			if (x >= linearFunction->getDomain()->getLowerBoundary()) {
 				return linearFunction->getY(x);
 			}
 		}
 		else if (linearFunction->getDomain()->upperBoundaryExist()) {
 			if (x <= linearFunction->getDomain()->getUpperBoundary()) {
 				return linearFunction->getY(x);
 			}
 		}
 		else {
 			return linearFunction->getY(x);
 		}
 	}
 
+	//the next two lines should be deleted, but if you call the function getY you have to check for NaN!
 	printf("DEFAULT!!!!!!!!!!!\n");
 	getchar();
-	//TODO: default return value is maybe not the best
-	return 0;
+
+	return std::numeric_limits<double>::quiet_NaN();
 }
 
 vector<LinearFunction*>& LinearFunctionBlock::get_all_LinearFunctions()
 {
 	return vLinearFunctions;
 }