implement getCurrent for LinearResistor

Source/Components/LinearResistor.cpp

@@ -23,5 +23,16 @@ void LinearResistor::applySystemMatrixStamp(SystemModel& system) {
 	}
 }
 
-	
-
+Complex LinearResistor::getCurrent(SystemModel& model) {
+	Real realVolt = 0, imagVolt = 0;
+	if (mNode1 >= 0) {
+		realVolt += model.getRealFromLeftSideVector(mNode1);
+		imagVolt += model.getImagFromLeftSideVector(mNode2);
+	}
+	if (mNode2 >= 0) {
+		realVolt -= model.getRealFromLeftSideVector(mNode1);
+		imagVolt -= model.getImagFromLeftSideVector(mNode2);
+	}
+	Complex curr(realVolt*mConductance, imagVolt*mConductance);
+	return curr;
+}

Source/Components/LinearResistor.h

@@ -36,6 +36,7 @@ namespace DPsim {
 		void applyRightSideVectorStamp(SystemModel& system) { }
 		void step(SystemModel& system, Real time) { }
 		void postStep(SystemModel& system) { }
+		Complex getCurrent(SystemModel& model);
 	};
 }
 #endif

Source/Examples/VillasTest.cpp

@@ -14,10 +14,12 @@ void DPsim::villasExample()
 	ExternalCurrentSource *ecs = new ExternalCurrentSource("i1", 1, 0);
 	comps.push_back(ecs);
 	comps.push_back(new LinearResistor("r1", 1, 2, 1));
-	comps.push_back(new LinearResistor("r2", 2, 0, 1));
+	LinearResistor *r2 = new LinearResistor("r2", 2, 0, 1);
+	comps.push_back(r2);
 	VillasInterface *villas = new VillasInterface("/villas1");
 	villas->registerCurrentSource(ecs, 0, 1);
-	villas->registerExportedVoltage(1, 2, 0, 1);
+	villas->registerExportedVoltage(1, 0, 0, 1);
+	villas->registerExportedCurrent(r2, 2, 3);
 
 	// Set up simulation
 	Real timeStep = 0.01;