Add -politer switch and auto-switch to explicit engine for MDP methods other than value iteration.

git-svn-id: https://www.prismmodelchecker.org/svn/prism/prism/trunk@6722 bbc10eb1-c90d-0410-af57-cb519fbb1720

prism/src/prism/Prism.java

@@ -1741,7 +1741,8 @@ public class Prism implements PrismSettingsListener
 			case EXPLICIT_FILES:
 				if (!getExplicit()) {
 					expf2mtbdd = new ExplicitFiles2MTBDD(this);
-					currentModel = expf2mtbdd.build(explicitFilesStatesFile, explicitFilesTransFile, explicitFilesLabelsFile, currentModulesFile, explicitFilesNumStates);
+					currentModel = expf2mtbdd.build(explicitFilesStatesFile, explicitFilesTransFile, explicitFilesLabelsFile, currentModulesFile,
+							explicitFilesNumStates);
 				} else {
 					throw new PrismException("Explicit import not yet supported for explicit engine");
 				}
@@ -2360,6 +2361,8 @@ public class Prism implements PrismSettingsListener
 	{
 		Result res = null;
 		Values definedPFConstants = propertiesFile.getConstantValues();
+		boolean engineSwitch = false;
+		int lastEngine = -1;
 
 		if (!digital)
 			mainLog.printSeparator();
@@ -2377,6 +2380,17 @@ public class Prism implements PrismSettingsListener
 			return modelCheckPTA(propertiesFile, prop.getExpression(), definedPFConstants);
 		}
 
+		// Auto-switch engine if required
+		if (currentModelType == ModelType.MDP) {
+			if (getMDPSolnMethod() != Prism.MDP_VALITER && !getExplicit()) {
+				mainLog.printWarning("Switching to explicit engine to allow use of chosen MDP solution method.");
+				engineSwitch = true;
+				lastEngine = getEngine();
+				setEngine(Prism.EXPLICIT);
+			}
+		}
+
+		try {
 			// Build model, if necessary
 			buildModelIfRequired();
 
@@ -2391,6 +2405,12 @@ public class Prism implements PrismSettingsListener
 				mc.setModulesFileAndPropertiesFile(currentModulesFile, propertiesFile);
 				res = mc.check(currentModelExpl, prop.getExpression());
 			}
+		} finally {
+			// Undo auto-switch (if any)
+			if (engineSwitch) {
+				setEngine(lastEngine);
+			}
+		}
 
 		// Return result
 		return res;

prism/src/prism/PrismSettings.java

@@ -809,6 +809,8 @@ public class PrismSettings implements Observer
 			set(PRISM_MDP_SOLN_METHOD, "Value iteration");
 		} else if (sw.equals("politer")) {
 			set(PRISM_MDP_SOLN_METHOD, "Policy iteration");
+		} else if (sw.equals("modpoliter")) {
+			set(PRISM_MDP_SOLN_METHOD, "Modified policy iteration");
 		} else if (sw.equals("linprog") || sw.equals("lp")) {
 			set(PRISM_MDP_SOLN_METHOD, "Linear programming");
 		}
@@ -1128,7 +1130,7 @@ public class PrismSettings implements Observer
 		mainLog.println("-explicit (or -ex) ............. Use the explicit engine");
 		mainLog.println("-ptamethod <name> .............. Specify PTA engine (games, digital) [default: games]");
 		mainLog.println();
-		mainLog.println("NUMERICAL SOLUTION OPTIONS:");
+		mainLog.println("SOLUTION METHODS (LINEAR EQUATIONS):");
 		mainLog.println("-power (or -pow, -pwr) ......... Use the Power method for numerical computation");
 		mainLog.println("-jacobi (or -jac) .............. Use Jacobi for numerical computation [default]");
 		mainLog.println("-gaussseidel (or -gs) .......... Use Gauss-Seidel for numerical computation");
@@ -1140,9 +1142,15 @@ public class PrismSettings implements Observer
 		mainLog.println("-bsor .......................... Use Backwards SOR for numerical computation");
 		mainLog.println("-psor .......................... Use Pseudo SOR for numerical computation");
 		mainLog.println("-bpsor ......................... Use Backwards Pseudo SOR for numerical computation");
+		mainLog.println("-omega <x> ..................... Set over-relaxation parameter (for JOR/SOR/...) [default: 0.9]");
+		mainLog.println();
+		mainLog.println("SOLUTION METHODS (MDPS):");
 		mainLog.println("-valiter ....................... Use value iteration for solving MDPs [default]");
+		mainLog.println("-gaussseidel (or -gs) .......... Use Gauss-Seidel value iteration for solving MDPs");
 		mainLog.println("-politer ....................... Use policy iteration for solving MDPs");
-		mainLog.println("-omega <x> ..................... Set over-relaxation parameter (for JOR/SOR/...) [default: 0.9]");
+		mainLog.println("-modpoliter .................... Use modified policy iteration for solving MDPs");
+		mainLog.println();
+		mainLog.println("SOLUTION METHOD SETTINGS");
 		mainLog.println("-relative (or -rel) ............ Use relative error for detecting convergence [default]");
 		mainLog.println("-absolute (or -abs) ............ Use absolute error for detecting convergence");
 		mainLog.println("-epsilon <x> (or -e <x>) ....... Set value of epsilon (for convergence check) [default: 1e-6]");