add lvector method to PySimulation

Source/PySimulation.cpp

@@ -78,6 +78,19 @@ void PySimulation::dealloc(PySimulation* self) {
 	Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
+PyObject* PySimulation::lvector(PyObject *self, PyObject *args) {
+	PySimulation *pySim = (PySimulation*) self;
+	if (pySim->state == StateRunning) {
+		PyErr_SetString(PyExc_SystemError, "Simulation currently running");
+		return nullptr;
+	}
+	Matrix& lvector = pySim->sim->getLeftSideVector();
+	PyObject* list = PyList_New(lvector.rows());
+	for (int i = 0; i < lvector.rows(); i++)
+		PyList_SetItem(list, i, PyFloat_FromDouble(lvector(i, 0)));
+	return list;
+}
+
 PyObject* PySimulation::start(PyObject *self, PyObject *args) {
 	PySimulation *pySim = (PySimulation*) self;
 	std::unique_lock<std::mutex> lk(*pySim->mut);

Source/PySimulation.h

@@ -45,6 +45,7 @@ namespace DPsim {
 		static void dealloc(PySimulation*);
 
 		// Methods that are actually available from Python
+		static PyObject* lvector(PyObject *self, PyObject *args);
 		static PyObject* start(PyObject *self, PyObject *args);
 		static PyObject* step(PyObject *self, PyObject *args);
 		static PyObject* stop(PyObject *self, PyObject *args);
@@ -53,6 +54,7 @@ namespace DPsim {
 	};
 
 	static PyMethodDef PySimulation_methods[] = {
+		{"lvector", PySimulation::lvector, METH_NOARGS, "Returns the left-side vector from the last step."},
 		{"start", PySimulation::start, METH_NOARGS, "Start the simulation, or resume if it is paused."},
 		{"step", PySimulation::step, METH_NOARGS, "Perform a single simulation step."},
 		{"stop", PySimulation::stop, METH_NOARGS, "Cancel the running simulation."},