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fixed a bug that prevented correct strategy generation in iterative solver

Former-commit-id: 1df15b439d
tempestpy_adaptions
dehnert 8 years ago
parent
commit
a663a37e21
  1. 20
      src/abstraction/prism/AbstractProgram.cpp
  2. 89
      src/modelchecker/abstraction/GameBasedMdpModelChecker.cpp
  3. 2
      src/solver/SymbolicGameSolver.cpp

20
src/abstraction/prism/AbstractProgram.cpp

@ -249,12 +249,14 @@ namespace storm {
// Construct the transition matrix by cutting away the transitions of unreachable states.
storm::dd::Add<DdType, ValueType> transitionMatrix = (game.bdd && reachableStates).template toAdd<ValueType>() * commandUpdateProbabilitiesAdd + deadlockTransitions;
// If there are bottom states, we need to mark all other states as non-bottom now.
// Extend the current game information with the 'non-bottom' tag before potentially adding bottom state transitions.
transitionMatrix *= (abstractionInformation.getBottomStateBdd(true, true) && abstractionInformation.getBottomStateBdd(false, true)).template toAdd<ValueType>();
reachableStates &= abstractionInformation.getBottomStateBdd(true, true);
initialStates &= abstractionInformation.getBottomStateBdd(true, true);
// If there are bottom transitions, exnted the transition matrix and reachable states now.
if (hasBottomStates) {
transitionMatrix *= (abstractionInformation.getBottomStateBdd(true, true) && abstractionInformation.getBottomStateBdd(false, true)).template toAdd<ValueType>();
transitionMatrix += bottomStateResult.transitions.template toAdd<ValueType>();
reachableStates &= abstractionInformation.getBottomStateBdd(true, true);
initialStates &= abstractionInformation.getBottomStateBdd(true, true);
reachableStates |= bottomStateResult.states;
}
@ -264,15 +266,11 @@ namespace storm {
allNondeterminismVariables.insert(abstractionInformation.getPlayer1Variables().begin(), abstractionInformation.getPlayer1Variables().end());
std::set<storm::expressions::Variable> allSourceVariables(abstractionInformation.getSourceVariables());
if (hasBottomStates) {
allSourceVariables.insert(abstractionInformation.getBottomStateVariable(true));
}
allSourceVariables.insert(abstractionInformation.getBottomStateVariable(true));
std::set<storm::expressions::Variable> allSuccessorVariables(abstractionInformation.getSuccessorVariables());
if (hasBottomStates) {
allSuccessorVariables.insert(abstractionInformation.getBottomStateVariable(false));
}
allSuccessorVariables.insert(abstractionInformation.getBottomStateVariable(false));
return std::make_unique<MenuGame<DdType, ValueType>>(abstractionInformation.getDdManagerAsSharedPointer(), reachableStates, initialStates, abstractionInformation.getDdManager().getBddZero(), transitionMatrix, bottomStateResult.states, allSourceVariables, allSuccessorVariables, hasBottomStates ? abstractionInformation.getExtendedSourceSuccessorVariablePairs() : abstractionInformation.getSourceSuccessorVariablePairs(), std::set<storm::expressions::Variable>(abstractionInformation.getPlayer1Variables().begin(), abstractionInformation.getPlayer1Variables().end()), usedPlayer2Variables, allNondeterminismVariables, auxVariables, abstractionInformation.getPredicateToBddMap());
return std::make_unique<MenuGame<DdType, ValueType>>(abstractionInformation.getDdManagerAsSharedPointer(), reachableStates, initialStates, abstractionInformation.getDdManager().getBddZero(), transitionMatrix, bottomStateResult.states, allSourceVariables, allSuccessorVariables, abstractionInformation.getExtendedSourceSuccessorVariablePairs(), std::set<storm::expressions::Variable>(abstractionInformation.getPlayer1Variables().begin(), abstractionInformation.getPlayer1Variables().end()), usedPlayer2Variables, allNondeterminismVariables, auxVariables, abstractionInformation.getPredicateToBddMap());
}
template <storm::dd::DdType DdType, typename ValueType>

89
src/modelchecker/abstraction/GameBasedMdpModelChecker.cpp

@ -235,6 +235,48 @@ namespace storm {
}
}
template<storm::dd::DdType Type, typename ValueType>
void refineAfterQuantitativeCheck(storm::abstraction::prism::PrismMenuGameAbstractor<Type, ValueType>& abstractor, storm::abstraction::MenuGame<Type, ValueType> const& game, std::pair<storm::dd::Bdd<Type>, storm::dd::Bdd<Type>> const& minStrategyPair, std::pair<storm::dd::Bdd<Type>, storm::dd::Bdd<Type>> const& maxStrategyPair, storm::dd::Bdd<Type> const& transitionMatrixBdd) {
// Build the fragment of states that is reachable by any combination of the player 1 and player 2 strategies.
storm::dd::Bdd<Type> reachableTransitions = minStrategyPair.second || maxStrategyPair.second;
reachableTransitions = (minStrategyPair.first && reachableTransitions) || (maxStrategyPair.first && reachableTransitions);
reachableTransitions &= transitionMatrixBdd;
reachableTransitions = reachableTransitions.existsAbstract(game.getNondeterminismVariables());
storm::dd::Bdd<Type> pivotStates = storm::utility::dd::computeReachableStates(game.getInitialStates(), reachableTransitions, game.getRowVariables(), game.getColumnVariables());
// Then constrain these states by the requirement that for either the lower or upper player 1 choice the player 2 choices must be different.
pivotStates &= ((minStrategyPair.first || maxStrategyPair.first) && (minStrategyPair.second.exclusiveOr(maxStrategyPair.second))).existsAbstract(game.getNondeterminismVariables());
STORM_LOG_ASSERT(!pivotStates.isZero(), "Unable to refine without pivot state candidates.");
// Now that we have the pivot state candidates, we need to pick one.
storm::dd::Bdd<Type> pivotState = pickPivotState<Type>(game.getInitialStates(), reachableTransitions, game.getRowVariables(), game.getColumnVariables(), pivotStates);
// Compute the lower and the upper choice for the pivot state.
std::set<storm::expressions::Variable> variablesToAbstract = game.getNondeterminismVariables();
variablesToAbstract.insert(game.getRowVariables().begin(), game.getRowVariables().end());
storm::dd::Bdd<Type> lowerChoice = pivotState && game.getExtendedTransitionMatrix().toBdd() && minStrategyPair.first;
storm::dd::Bdd<Type> lowerChoice1 = (lowerChoice && minStrategyPair.second).existsAbstract(variablesToAbstract);
storm::dd::Bdd<Type> lowerChoice2 = (lowerChoice && maxStrategyPair.second).existsAbstract(variablesToAbstract);
bool lowerChoicesDifferent = !lowerChoice1.exclusiveOr(lowerChoice2).isZero();
if (lowerChoicesDifferent) {
STORM_LOG_TRACE("Refining based on lower choice.");
abstractor.refine(pivotState, (pivotState && minStrategyPair.first).existsAbstract(game.getRowVariables()), lowerChoice1, lowerChoice2);
} else {
storm::dd::Bdd<Type> upperChoice = pivotState && game.getExtendedTransitionMatrix().toBdd() && maxStrategyPair.first;
storm::dd::Bdd<Type> upperChoice1 = (upperChoice && minStrategyPair.second).existsAbstract(variablesToAbstract);
storm::dd::Bdd<Type> upperChoice2 = (upperChoice && maxStrategyPair.second).existsAbstract(variablesToAbstract);
bool upperChoicesDifferent = !upperChoice1.exclusiveOr(upperChoice2).isZero();
if (upperChoicesDifferent) {
STORM_LOG_TRACE("Refining based on upper choice.");
abstractor.refine(pivotState, (pivotState && maxStrategyPair.first).existsAbstract(game.getRowVariables()), upperChoice1, upperChoice2);
} else {
STORM_LOG_ASSERT(false, "Did not find choices from which to derive predicates.");
}
}
}
template<storm::dd::DdType Type, typename ValueType>
struct MaybeStateResult {
MaybeStateResult() = default;
@ -275,17 +317,8 @@ namespace storm {
storm::utility::solver::SymbolicGameSolverFactory<Type, ValueType> solverFactory;
std::unique_ptr<storm::solver::SymbolicGameSolver<Type, ValueType>> solver = solverFactory.create(submatrix, maybeStates, game.getIllegalPlayer1Mask(), game.getIllegalPlayer2Mask(), game.getRowVariables(), game.getColumnVariables(), game.getRowColumnMetaVariablePairs(), game.getPlayer1Variables(), game.getPlayer2Variables());
solver->setGeneratePlayersStrategies(true);
auto values = solver->solveGame(player1Direction, player2Direction, startVector, subvector);
storm::dd::Bdd<Type> player1Strategy = solver->getPlayer1Strategy();
storm::dd::Bdd<Type> player2Strategy = solver->getPlayer2Strategy();
// If we were given a starting point, we fix the strategies now. That is, we only deviate from the
if (startInfo) {
player1Strategy = values.greater(startInfo.get().values).ite(player1Strategy, startInfo.get().player1Strategy);
player1Strategy = values.greater(startInfo.get().values).ite(player1Strategy, startInfo.get().player1Strategy);
}
return MaybeStateResult<Type, ValueType>(values, player1Strategy, player2Strategy);
auto values = solver->solveGame(player1Direction, player2Direction, startVector, subvector, startInfo ? boost::make_optional(startInfo.get().player1Strategy) : boost::none, startInfo ? boost::make_optional(startInfo.get().player2Strategy) : boost::none);
return MaybeStateResult<Type, ValueType>(values, solver->getPlayer1Strategy(), solver->getPlayer2Strategy());
}
template<storm::dd::DdType Type, typename ValueType>
@ -380,13 +413,13 @@ namespace storm {
storm::dd::Add<Type, ValueType> initialStatesAdd = game.getInitialStates().template toAdd<ValueType>();
ValueType minValue = (prob01.min.second.states && game.getInitialStates()) == game.getInitialStates() ? storm::utility::one<ValueType>() : storm::utility::zero<ValueType>();
MaybeStateResult<Type, ValueType> minMaybeStateResult;
MaybeStateResult<Type, ValueType> minMaybeStateResult(game.getManager().template getAddZero<ValueType>(), game.getManager().getBddZero(), game.getManager().getBddZero());
if (!maybeMin.isZero()) {
minMaybeStateResult = solveMaybeStates(player1Direction, storm::OptimizationDirection::Minimize, game, maybeMin, prob01.min.second.states);
minResult += minMaybeStateResult.values;
storm::dd::Add<Type, ValueType> initialStateMin = initialStatesAdd * minResult;
// Here we can only require a non-zero count of *at most* one, because the result may actually be 0.
STORM_LOG_ASSERT(initialStateMin.getNonZeroCount() <= 1, "Wrong number of results for initial states.");
STORM_LOG_ASSERT(initialStateMin.getNonZeroCount() <= 1, "Wrong number of results for initial states. Expected <= 1, but got " << initialStateMin.getNonZeroCount() << ".");
minValue = initialStateMin.getMax();
}
STORM_LOG_TRACE("Obtained quantitative lower bound " << minValue << ".");
@ -398,15 +431,14 @@ namespace storm {
}
ValueType maxValue = (prob01.max.second.states && game.getInitialStates()) == game.getInitialStates() ? storm::utility::one<ValueType>() : storm::utility::zero<ValueType>();
MaybeStateResult<Type, ValueType> maxMaybeStateResult;
MaybeStateResult<Type, ValueType> maxMaybeStateResult(game.getManager().template getAddZero<ValueType>(), game.getManager().getBddZero(), game.getManager().getBddZero());
if (!maybeMax.isZero()) {
// FIXME: fix strategy: only change if improved.
maxMaybeStateResult = solveMaybeStates(player1Direction, storm::OptimizationDirection::Maximize, game, maybeMax, prob01.max.second.states, boost::optional<MaybeStateResult<Type, ValueType>>(minMaybeStateResult));
maxMaybeStateResult = solveMaybeStates(player1Direction, storm::OptimizationDirection::Maximize, game, maybeMax, prob01.max.second.states, boost::make_optional(minMaybeStateResult));
maxResult += maxMaybeStateResult.values;
storm::dd::Add<Type, ValueType> initialStateMax = (initialStatesAdd * maxResult);
// Unlike in the min-case, we can require a non-zero count of 1 here, because if the max was in
// fact 0, the result would be 0, which would have been detected earlier by the graph algorithms.
STORM_LOG_ASSERT(initialStateMax.getNonZeroCount() == 1, "Wrong number of results for initial states.");
STORM_LOG_ASSERT(initialStateMax.getNonZeroCount() == 1, "Wrong number of results for initial states. Expected 1, but got " << initialStateMax.getNonZeroCount() << ".");
maxValue = initialStateMax.getMax();
}
STORM_LOG_TRACE("Obtained quantitative upper bound " << maxValue << ".");
@ -427,7 +459,13 @@ namespace storm {
// If we arrived at this point, it means that we have all qualitative and quantitative information
// about the game, but we could not yet answer the query. In this case, we need to refine.
STORM_LOG_ASSERT(false, "Quantiative refinement not yet there. :)");
// Start by extending the quantitative strategies by the qualitative ones.
minMaybeStateResult.player1Strategy |= prob01.min.first.getPlayer1Strategy() || prob01.min.second.getPlayer1Strategy();
minMaybeStateResult.player2Strategy |= prob01.min.first.getPlayer2Strategy() || prob01.min.second.getPlayer2Strategy();
maxMaybeStateResult.player1Strategy |= prob01.max.first.getPlayer1Strategy() || prob01.max.second.getPlayer1Strategy();
maxMaybeStateResult.player2Strategy |= prob01.max.first.getPlayer2Strategy() || prob01.max.second.getPlayer2Strategy();
refineAfterQuantitativeCheck(abstractor, game, std::make_pair(minMaybeStateResult.player1Strategy, minMaybeStateResult.player2Strategy), std::make_pair(maxMaybeStateResult.player1Strategy, maxMaybeStateResult.player2Strategy), transitionMatrixBdd);
}
}
@ -438,15 +476,18 @@ namespace storm {
template<storm::dd::DdType Type, typename ValueType>
std::pair<storm::utility::graph::GameProb01Result<Type>, storm::utility::graph::GameProb01Result<Type>> GameBasedMdpModelChecker<Type, ValueType>::computeProb01States(storm::OptimizationDirection player1Direction, storm::OptimizationDirection player2Direction, storm::abstraction::MenuGame<Type, ValueType> const& game, storm::dd::Bdd<Type> const& transitionMatrixBdd, storm::dd::Bdd<Type> const& constraintStates, storm::dd::Bdd<Type> const& targetStates) {
// Compute the states with probability 0/1.
storm::utility::graph::GameProb01Result<Type> prob0 = storm::utility::graph::performProb0(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, player2Direction == storm::OptimizationDirection::Minimize, player2Direction == storm::OptimizationDirection::Minimize);
storm::utility::graph::GameProb01Result<Type> prob1 = storm::utility::graph::performProb1(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, player2Direction == storm::OptimizationDirection::Maximize, player2Direction == storm::OptimizationDirection::Maximize);
// storm::utility::graph::GameProb01Result<Type> prob0 = storm::utility::graph::performProb0(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, player2Direction == storm::OptimizationDirection::Minimize, player2Direction == storm::OptimizationDirection::Minimize);
// storm::utility::graph::GameProb01Result<Type> prob1 = storm::utility::graph::performProb1(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, player2Direction == storm::OptimizationDirection::Maximize, player2Direction == storm::OptimizationDirection::Maximize);
storm::utility::graph::GameProb01Result<Type> prob0 = storm::utility::graph::performProb0(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, true, true);
storm::utility::graph::GameProb01Result<Type> prob1 = storm::utility::graph::performProb1(game, transitionMatrixBdd, constraintStates, targetStates, player1Direction, player2Direction, true, true);
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Minimize || (prob0.hasPlayer1Strategy() && !prob0.getPlayer1Strategy().isZero()), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Minimize || (prob0.hasPlayer2Strategy() && !prob0.getPlayer2Strategy().isZero()), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Maximize || (prob1.hasPlayer1Strategy() && !prob1.getPlayer1Strategy().isZero()), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Maximize || (prob1.hasPlayer2Strategy() && !prob1.getPlayer2Strategy().isZero()), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Minimize || (prob0.hasPlayer1Strategy() && (prob0.states.isZero() || !prob0.getPlayer1Strategy().isZero())), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Minimize || (prob0.hasPlayer2Strategy() && (prob0.states.isZero() || !prob0.getPlayer2Strategy().isZero())), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Maximize || (prob1.hasPlayer1Strategy() && (prob1.states.isZero() || !prob1.getPlayer1Strategy().isZero())), "Unable to proceed without strategy.");
STORM_LOG_ASSERT(player2Direction != storm::OptimizationDirection::Maximize || (prob1.hasPlayer2Strategy() && (prob1.states.isZero() || !prob1.getPlayer2Strategy().isZero())), "Unable to proceed without strategy.");
STORM_LOG_TRACE("Player 1: " << player1Direction << ", player 2: " << player2Direction << ": " << prob0.states.getNonZeroCount() << " 'no' states, " << prob1.states.getNonZeroCount() << " 'yes' states.");
return std::make_pair(prob0, prob1);
}

2
src/solver/SymbolicGameSolver.cpp

@ -46,7 +46,7 @@ namespace storm {
// If we are required to generate a player 2 strategy based on another one that is not the zero strategy,
// we need to determine the values, because only then we can update the strategy only if necessary.
previousPlayer2Values = ((this->A * player2Strategy.get().template toAdd<ValueType>()).multiplyMatrix(x.swapVariables(this->rowColumnMetaVariablePairs), this->columnMetaVariables) + b).sumAbstract(this->player2Variables);
previousPlayer2Values = (player2Strategy.get().template toAdd<ValueType>() * (this->A.multiplyMatrix(x.swapVariables(this->rowColumnMetaVariablePairs), this->columnMetaVariables) + b)).sumAbstract(this->player2Variables);
} else {
player2Strategy = A.getDdManager().getBddZero();
previousPlayer2Values = A.getDdManager().template getAddZero<ValueType>();

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