Enforce no end components when we want to compute a scheduler from a minmax equation system

src/storm/solver/IterativeMinMaxLinearEquationSolver.cpp

@@ -255,6 +255,11 @@ namespace storm {
             // Start by copying the requirements of the linear equation solver.
             MinMaxLinearEquationSolverRequirements requirements(this->linearEquationSolverFactory->getRequirements());
             
+            // In case we perform value iteration and need to retrieve a scheduler, end components are forbidden
+            if (this->getSettings().getSolutionMethod() == IterativeMinMaxLinearEquationSolverSettings<ValueType>::SolutionMethod::ValueIteration && isTrackSchedulerSet()) {
+                requirements.requireNoEndComponents();
+            }
+            
             // Guide requirements by whether or not we force soundness.
             if (this->getSettings().getForceSoundness()) {
                 // Only add requirements for value iteration here as the policy iteration requirements are indifferent

src/storm/solver/LpMinMaxLinearEquationSolver.cpp

@@ -108,6 +108,21 @@ namespace storm {
             StandardMinMaxLinearEquationSolver<ValueType>::clearCache();
         }
         
+        
+        template<typename ValueType>
+        MinMaxLinearEquationSolverRequirements LpMinMaxLinearEquationSolver<ValueType>::getRequirements(EquationSystemType const& equationSystemType, boost::optional<storm::solver::OptimizationDirection> const& direction) const {
+            
+            MinMaxLinearEquationSolverRequirements requirements;
+            
+            // In case we need to retrieve a scheduler, end components are forbidden
+            if (isTrackSchedulerSet()) {
+                requirements.requireNoEndComponents();
+            }
+            
+            return  requirements;
+        }
+
+        
         template<typename ValueType>
         LpMinMaxLinearEquationSolverFactory<ValueType>::LpMinMaxLinearEquationSolverFactory(bool trackScheduler) : StandardMinMaxLinearEquationSolverFactory<ValueType>(MinMaxMethodSelection::LinearProgramming, trackScheduler), lpSolverFactory(std::make_unique<storm::utility::solver::LpSolverFactory<ValueType>>()) {
             // Intentionally left empty

src/storm/solver/LpMinMaxLinearEquationSolver.h

@@ -18,6 +18,8 @@ namespace storm {
 
             virtual void clearCache() const override;
 
+            virtual MinMaxLinearEquationSolverRequirements getRequirements(EquationSystemType const& equationSystemType, boost::optional<storm::solver::OptimizationDirection> const& direction = boost::none) const override;
+            
         private:
             std::unique_ptr<storm::utility::solver::LpSolverFactory<ValueType>> lpSolverFactory;
         };