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#include "ApproximatePOMDPModelchecker.h"
#include <boost/algorithm/string.hpp>
#include "storm/utility/ConstantsComparator.h"
#include "storm/models/sparse/Dtmc.h"
#include "storm/models/sparse/StandardRewardModel.h"
#include "storm/modelchecker/prctl/SparseDtmcPrctlModelChecker.h"
#include "storm/utility/vector.h"
#include "storm/modelchecker/results/CheckResult.h"
#include "storm/modelchecker/results/ExplicitQualitativeCheckResult.h"
#include "storm/modelchecker/results/ExplicitQuantitativeCheckResult.h"
#include "storm/modelchecker/hints/ExplicitModelCheckerHint.cpp"
#include "storm/api/properties.h"
#include "storm/api/export.h"
#include "storm-parsers/api/storm-parsers.h"
namespace storm {
namespace pomdp {
namespace modelchecker {
template<typename ValueType, typename RewardModelType>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::ApproximatePOMDPModelchecker() {
precision = 0.000000001;
cc = storm::utility::ConstantsComparator<ValueType>(storm::utility::convertNumber<ValueType>(precision), false);
useMdp = true;
maxIterations = 1000;
cacheSubsimplices = false;
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::refineReachabilityProbability(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min, uint64_t gridResolution,
double explorationThreshold) {
std::srand(time(NULL));
// Compute easy upper and lower bounds
storm::utility::Stopwatch underlyingWatch(true);
// Compute the results on the underlying MDP as a basic overapproximation
storm::models::sparse::StateLabeling underlyingMdpLabeling(pomdp.getStateLabeling());
// TODO: Is the following really necessary
underlyingMdpLabeling.addLabel("__goal__");
std::vector<uint64_t> goalStates;
for (auto const &targetObs : targetObservations) {
for (auto const &goalState : pomdp.getStatesWithObservation(targetObs)) {
underlyingMdpLabeling.addLabelToState("__goal__", goalState);
}
}
storm::models::sparse::Mdp<ValueType, RewardModelType> underlyingMdp(pomdp.getTransitionMatrix(), underlyingMdpLabeling, pomdp.getRewardModels());
auto underlyingModel = std::static_pointer_cast<storm::models::sparse::Model<ValueType, RewardModelType>>(
std::make_shared<storm::models::sparse::Mdp<ValueType, RewardModelType>>(underlyingMdp));
std::string initPropString = min ? "Pmin" : "Pmax";
initPropString += "=? [F \"__goal__\"]";
std::vector<storm::jani::Property> propVector = storm::api::parseProperties(initPropString);
std::shared_ptr<storm::logic::Formula const> underlyingProperty = storm::api::extractFormulasFromProperties(propVector).front();
STORM_PRINT("Underlying MDP" << std::endl)
underlyingMdp.printModelInformationToStream(std::cout);
std::unique_ptr<storm::modelchecker::CheckResult> underlyingRes(
storm::api::verifyWithSparseEngine<ValueType>(underlyingModel, storm::api::createTask<ValueType>(underlyingProperty, false)));
STORM_LOG_ASSERT(underlyingRes, "Result not exist.");
underlyingRes->filter(storm::modelchecker::ExplicitQualitativeCheckResult(storm::storage::BitVector(underlyingMdp.getNumberOfStates(), true)));
auto initialOverApproxMap = underlyingRes->asExplicitQuantitativeCheckResult<ValueType>().getValueMap();
underlyingWatch.stop();
storm::utility::Stopwatch positionalWatch(true);
// we define some positional scheduler for the POMDP as a basic lower bound
storm::storage::Scheduler<ValueType> pomdpScheduler(pomdp.getNumberOfStates());
for (uint32_t obs = 0; obs < pomdp.getNrObservations(); ++obs) {
auto obsStates = pomdp.getStatesWithObservation(obs);
// select a random action for all states with the same observation
uint64_t chosenAction = std::rand() % pomdp.getNumberOfChoices(obsStates.front());
for (auto const &state : obsStates) {
pomdpScheduler.setChoice(chosenAction, state);
}
}
auto underApproxModel = underlyingMdp.applyScheduler(pomdpScheduler, false);
STORM_PRINT("Random Positional Scheduler" << std::endl)
underApproxModel->printModelInformationToStream(std::cout);
std::unique_ptr<storm::modelchecker::CheckResult> underapproxRes(
storm::api::verifyWithSparseEngine<ValueType>(underApproxModel, storm::api::createTask<ValueType>(underlyingProperty, false)));
STORM_LOG_ASSERT(underapproxRes, "Result not exist.");
underapproxRes->filter(storm::modelchecker::ExplicitQualitativeCheckResult(storm::storage::BitVector(underApproxModel->getNumberOfStates(), true)));
auto underApproxMap = underapproxRes->asExplicitQuantitativeCheckResult<ValueType>().getValueMap();
positionalWatch.stop();
STORM_PRINT("Pre-Processing Results: " << initialOverApproxMap[underlyingMdp.getInitialStates().getNextSetIndex(0)] << " // "
<< underApproxMap[underApproxModel->getInitialStates().getNextSetIndex(0)] << std::endl)
STORM_PRINT("Preprocessing Times: " << underlyingWatch << " / " << positionalWatch << std::endl)
// Initialize the resolution mapping. For now, we always give all beliefs with the same observation the same resolution.
// This can probably be improved (i.e. resolutions for single belief states)
STORM_PRINT("Initial Resolution: " << gridResolution << std::endl)
std::vector<uint64_t> observationResolutionVector(pomdp.getNrObservations(), gridResolution);
std::set<uint32_t> changedObservations;
uint64_t underApproxModelSize = 200;
uint64_t refinementCounter = 1;
STORM_PRINT("==============================" << std::endl << "Initial Computation" << std::endl << "------------------------------" << std::endl)
std::shared_ptr<RefinementComponents<ValueType>> res = computeFirstRefinementStep(pomdp, targetObservations, min, observationResolutionVector, false,
explorationThreshold, initialOverApproxMap, underApproxMap, underApproxModelSize);
ValueType lastMinScore = storm::utility::infinity<ValueType>();
while (refinementCounter < 1000) {
// TODO the actual refinement
// choose which observation(s) to refine
std::vector<ValueType> obsAccumulator(pomdp.getNrObservations(), storm::utility::zero<ValueType>());
std::vector<uint64_t> beliefCount(pomdp.getNrObservations(), 0);
bsmap_type::right_map::const_iterator underApproxStateBeliefIter = res->underApproxBeliefStateMap.right.begin();
while (underApproxStateBeliefIter != res->underApproxBeliefStateMap.right.end()) {
auto currentBelief = res->beliefList[underApproxStateBeliefIter->second];
beliefCount[currentBelief.observation] += 1;
bsmap_type::left_const_iterator overApproxBeliefStateIter = res->overApproxBeliefStateMap.left.find(underApproxStateBeliefIter->second);
if (overApproxBeliefStateIter != res->overApproxBeliefStateMap.left.end()) {
// If there is an over-approximate value for the belief, use it
auto diff = res->overApproxMap[overApproxBeliefStateIter->second] - res->underApproxMap[underApproxStateBeliefIter->first];
obsAccumulator[currentBelief.observation] += diff;
} else {
//otherwise, we approximate a value TODO this is critical, we have to think about it
auto overApproxValue = storm::utility::zero<ValueType>();
auto temp = computeSubSimplexAndLambdas(currentBelief.probabilities, observationResolutionVector[currentBelief.observation], pomdp.getNumberOfStates());
auto subSimplex = temp.first;
auto lambdas = temp.second;
for (size_t j = 0; j < lambdas.size(); ++j) {
if (!cc.isEqual(lambdas[j], storm::utility::zero<ValueType>())) {
uint64_t approxId = getBeliefIdInVector(res->beliefList, currentBelief.observation, subSimplex[j]);
bsmap_type::left_const_iterator approxIter = res->overApproxBeliefStateMap.left.find(approxId);
if (approxIter != res->overApproxBeliefStateMap.left.end()) {
overApproxValue += lambdas[j] * res->overApproxMap[approxIter->second];
} else {
overApproxValue += lambdas[j];
}
}
}
obsAccumulator[currentBelief.observation] += overApproxValue - res->underApproxMap[underApproxStateBeliefIter->first];
}
++underApproxStateBeliefIter;
}
/*for (uint64_t i = 0; i < obsAccumulator.size(); ++i) {
obsAccumulator[i] /= storm::utility::convertNumber<ValueType>(beliefCount[i]);
}*/
changedObservations.clear();
//TODO think about some other scoring methods
auto maxAvgDifference = *std::max_element(obsAccumulator.begin(), obsAccumulator.end());
//if (cc.isEqual(maxAvgDifference, lastMinScore) || cc.isLess(lastMinScore, maxAvgDifference)) {
lastMinScore = maxAvgDifference;
auto maxRes = *std::max_element(observationResolutionVector.begin(), observationResolutionVector.end());
STORM_PRINT("Set all to " << maxRes + 1 << std::endl)
for (uint64_t i = 0; i < pomdp.getNrObservations(); ++i) {
observationResolutionVector[i] = maxRes + 1;
changedObservations.insert(i);
}
/*} else {
lastMinScore = std::min(maxAvgDifference, lastMinScore);
STORM_PRINT("Max Score: " << maxAvgDifference << std::endl)
STORM_PRINT("Last Min Score: " << lastMinScore << std::endl)
//STORM_PRINT("Obs(beliefCount): Score " << std::endl << "-------------------------------------" << std::endl)
for (uint64_t i = 0; i < pomdp.getNrObservations(); ++i) {
//STORM_PRINT(i << "(" << beliefCount[i] << "): " << obsAccumulator[i])
if (cc.isEqual(obsAccumulator[i], maxAvgDifference)) {
//STORM_PRINT(" *** ")
observationResolutionVector[i] += 1;
changedObservations.insert(i);
}
//STORM_PRINT(std::endl)
}
}*/
if (underApproxModelSize < std::numeric_limits<uint64_t>::max() - 101) {
underApproxModelSize += 100;
}
STORM_PRINT(
"==============================" << std::endl << "Refinement Step " << refinementCounter << std::endl << "------------------------------" << std::endl)
res = computeRefinementStep(pomdp, targetObservations, min, observationResolutionVector, false, explorationThreshold,
res, changedObservations, initialOverApproxMap, underApproxMap, underApproxModelSize);
//storm::api::exportSparseModelAsDot(res->overApproxModelPtr, "oa_model_" + std::to_string(refinementCounter +1) + ".dot");
if (cc.isEqual(res->overApproxValue, res->underApproxValue)) {
break;
}
++refinementCounter;
}
return std::make_unique<POMDPCheckResult<ValueType>>(POMDPCheckResult<ValueType>{res->overApproxValue, res->underApproxValue});
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachabilityOTF(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
std::vector<uint64_t> &observationResolutionVector,
bool computeRewards, double explorationThreshold,
boost::optional<std::map<uint64_t, ValueType>> overApproximationMap,
boost::optional<std::map<uint64_t, ValueType>> underApproximationMap,
uint64_t maxUaModelSize) {
STORM_PRINT("Use On-The-Fly Grid Generation" << std::endl)
auto result = computeFirstRefinementStep(pomdp, targetObservations, min, observationResolutionVector, computeRewards, explorationThreshold, overApproximationMap,
underApproximationMap, maxUaModelSize);
return std::make_unique<POMDPCheckResult<ValueType>>(POMDPCheckResult<ValueType>{result->overApproxValue, result->underApproxValue});
}
template<typename ValueType, typename RewardModelType>
std::shared_ptr<RefinementComponents<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeFirstRefinementStep(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
std::vector<uint64_t> &observationResolutionVector,
bool computeRewards, double explorationThreshold,
boost::optional<std::map<uint64_t, ValueType>> overApproximationMap,
boost::optional<std::map<uint64_t, ValueType>> underApproximationMap,
uint64_t maxUaModelSize) {
bool boundMapsSet = overApproximationMap && underApproximationMap;
std::map<uint64_t, ValueType> overMap;
std::map<uint64_t, ValueType> underMap;
if (boundMapsSet) {
overMap = overApproximationMap.value();
underMap = underApproximationMap.value();
}
std::vector<storm::pomdp::Belief<ValueType>> beliefList;
std::vector<bool> beliefIsTarget;
std::vector<storm::pomdp::Belief<ValueType>> beliefGrid;
//Use caching to avoid multiple computation of the subsimplices and lambdas
std::map<uint64_t, std::vector<std::map<uint64_t, ValueType>>> subSimplexCache;
std::map<uint64_t, std::vector<ValueType>> lambdaCache;
bsmap_type beliefStateMap;
std::deque<uint64_t> beliefsToBeExpanded;
// current ID -> action -> reward
std::map<uint64_t, std::vector<ValueType>> beliefActionRewards;
uint64_t nextId = 0;
storm::utility::Stopwatch expansionTimer(true);
// Initial belief always has belief ID 0
storm::pomdp::Belief<ValueType> initialBelief = getInitialBelief(pomdp, nextId);
++nextId;
beliefList.push_back(initialBelief);
beliefIsTarget.push_back(targetObservations.find(initialBelief.observation) != targetObservations.end());
// These are the components to build the MDP from the grid
// Reserve states 0 and 1 as always sink/goal states
std::vector<std::vector<std::map<uint64_t, ValueType>>> mdpTransitions = {{{{0, storm::utility::one<ValueType>()}}},
{{{1, storm::utility::one<ValueType>()}}}};
// Hint vector for the MDP modelchecker (initialize with constant sink/goal values)
std::vector<ValueType> hintVector = {storm::utility::zero<ValueType>(), storm::utility::one<ValueType>()};
std::vector<uint64_t> targetStates = {1};
uint64_t mdpStateId = 2;
beliefStateMap.insert(bsmap_type::value_type(initialBelief.id, mdpStateId));
++mdpStateId;
// Map to save the weighted values resulting from the preprocessing for the beliefs / indices in beliefSpace
std::map<uint64_t, ValueType> weightedSumOverMap;
std::map<uint64_t, ValueType> weightedSumUnderMap;
// for the initial belief, add the triangulated initial states
auto initTemp = computeSubSimplexAndLambdas(initialBelief.probabilities, observationResolutionVector[initialBelief.observation], pomdp.getNumberOfStates());
auto initSubSimplex = initTemp.first;
auto initLambdas = initTemp.second;
if (cacheSubsimplices) {
subSimplexCache[0] = initSubSimplex;
lambdaCache[0] = initLambdas;
}
std::vector<std::map<uint64_t, ValueType>> initTransitionsInBelief;
std::map<uint64_t, ValueType> initTransitionInActionBelief;
bool initInserted = false;
for (size_t j = 0; j < initLambdas.size(); ++j) {
if (!cc.isEqual(initLambdas[j], storm::utility::zero<ValueType>())) {
uint64_t searchResult = getBeliefIdInVector(beliefList, initialBelief.observation, initSubSimplex[j]);
if (searchResult == uint64_t(-1) || (searchResult == 0 && !initInserted)) {
if (searchResult == 0) {
// the initial belief is on the grid itself
if (boundMapsSet) {
auto tempWeightedSumOver = storm::utility::zero<ValueType>();
auto tempWeightedSumUnder = storm::utility::zero<ValueType>();
for (uint64_t i = 0; i < initSubSimplex[j].size(); ++i) {
tempWeightedSumOver += initSubSimplex[j][i] * storm::utility::convertNumber<ValueType>(overMap[i]);
tempWeightedSumUnder += initSubSimplex[j][i] * storm::utility::convertNumber<ValueType>(underMap[i]);
}
weightedSumOverMap[initialBelief.id] = tempWeightedSumOver;
weightedSumUnderMap[initialBelief.id] = tempWeightedSumUnder;
}
initInserted = true;
beliefGrid.push_back(initialBelief);
beliefsToBeExpanded.push_back(0);
hintVector.push_back(targetObservations.find(initialBelief.observation) != targetObservations.end() ? storm::utility::one<ValueType>()
: storm::utility::zero<ValueType>());
} else {
// if the triangulated belief was not found in the list, we place it in the grid and add it to the work list
if (boundMapsSet) {
auto tempWeightedSumOver = storm::utility::zero<ValueType>();
auto tempWeightedSumUnder = storm::utility::zero<ValueType>();
for (uint64_t i = 0; i < initSubSimplex[j].size(); ++i) {
tempWeightedSumOver += initSubSimplex[j][i] * storm::utility::convertNumber<ValueType>(overMap[i]);
tempWeightedSumUnder += initSubSimplex[j][i] * storm::utility::convertNumber<ValueType>(underMap[i]);
}
weightedSumOverMap[nextId] = tempWeightedSumOver;
weightedSumUnderMap[nextId] = tempWeightedSumUnder;
}
storm::pomdp::Belief<ValueType> gridBelief = {nextId, initialBelief.observation, initSubSimplex[j]};
beliefList.push_back(gridBelief);
beliefGrid.push_back(gridBelief);
beliefIsTarget.push_back(targetObservations.find(initialBelief.observation) != targetObservations.end());
beliefsToBeExpanded.push_back(nextId);
++nextId;
hintVector.push_back(targetObservations.find(initialBelief.observation) != targetObservations.end() ? storm::utility::one<ValueType>()
: storm::utility::zero<ValueType>());
beliefStateMap.insert(bsmap_type::value_type(nextId, mdpStateId));
initTransitionInActionBelief[mdpStateId] = initLambdas[j];
++nextId;
++mdpStateId;
}
}
}
}
// If the initial belief is not on the grid, we add the transitions from our initial MDP state to the triangulated beliefs
if (!initTransitionInActionBelief.empty()) {
initTransitionsInBelief.push_back(initTransitionInActionBelief);
mdpTransitions.push_back(initTransitionsInBelief);
}
//beliefsToBeExpanded.push_back(initialBelief.id); I'm curious what happens if we do this instead of first triangulating. Should do nothing special if belief is on grid, otherwise it gets interesting
// Expand the beliefs to generate the grid on-the-fly
if (explorationThreshold > 0) {
STORM_PRINT("Exploration threshold: " << explorationThreshold << std::endl)
}
while (!beliefsToBeExpanded.empty()) {
uint64_t currId = beliefsToBeExpanded.front();
beliefsToBeExpanded.pop_front();
bool isTarget = beliefIsTarget[currId];
if (boundMapsSet && cc.isLess(weightedSumOverMap[currId] - weightedSumUnderMap[currId], storm::utility::convertNumber<ValueType>(explorationThreshold))) {
mdpTransitions.push_back({{{1, weightedSumOverMap[currId]}, {0, storm::utility::one<ValueType>() - weightedSumOverMap[currId]}}});
continue;
}
if (isTarget) {
// Depending on whether we compute rewards, we select the right initial result
// MDP stuff
targetStates.push_back(beliefStateMap.left.at(currId));
mdpTransitions.push_back({{{beliefStateMap.left.at(currId), storm::utility::one<ValueType>()}}});
} else {
uint64_t representativeState = pomdp.getStatesWithObservation(beliefList[currId].observation).front();
uint64_t numChoices = pomdp.getNumberOfChoices(representativeState);
std::vector<ValueType> actionRewardsInState(numChoices);
std::vector<std::map<uint64_t, ValueType>> transitionsInBelief;
for (uint64_t action = 0; action < numChoices; ++action) {
std::map<uint32_t, ValueType> actionObservationProbabilities = computeObservationProbabilitiesAfterAction(pomdp, beliefList[currId], action);
std::map<uint64_t, ValueType> transitionInActionBelief;
for (auto iter = actionObservationProbabilities.begin(); iter != actionObservationProbabilities.end(); ++iter) {
uint32_t observation = iter->first;
// THIS CALL IS SLOW
// TODO speed this up
uint64_t idNextBelief = getBeliefAfterActionAndObservation(pomdp, beliefList, beliefIsTarget, targetObservations, beliefList[currId], action,
observation, nextId);
nextId = beliefList.size();
//Triangulate here and put the possibly resulting belief in the grid
std::vector<std::map<uint64_t, ValueType>> subSimplex;
std::vector<ValueType> lambdas;
if (cacheSubsimplices && subSimplexCache.count(idNextBelief) > 0) {
subSimplex = subSimplexCache[idNextBelief];
lambdas = lambdaCache[idNextBelief];
} else {
auto temp = computeSubSimplexAndLambdas(beliefList[idNextBelief].probabilities,
observationResolutionVector[beliefList[idNextBelief].observation], pomdp.getNumberOfStates());
subSimplex = temp.first;
lambdas = temp.second;
if (cacheSubsimplices) {
subSimplexCache[idNextBelief] = subSimplex;
lambdaCache[idNextBelief] = lambdas;
}
}
for (size_t j = 0; j < lambdas.size(); ++j) {
if (!cc.isEqual(lambdas[j], storm::utility::zero<ValueType>())) {
auto approxId = getBeliefIdInVector(beliefGrid, observation, subSimplex[j]);
if (approxId == uint64_t(-1)) {
// if the triangulated belief was not found in the list, we place it in the grid and add it to the work list
storm::pomdp::Belief<ValueType> gridBelief = {nextId, observation, subSimplex[j]};
beliefList.push_back(gridBelief);
beliefGrid.push_back(gridBelief);
beliefIsTarget.push_back(targetObservations.find(observation) != targetObservations.end());
// compute overapproximate value using MDP result map
if (boundMapsSet) {
auto tempWeightedSumOver = storm::utility::zero<ValueType>();
auto tempWeightedSumUnder = storm::utility::zero<ValueType>();
for (uint64_t i = 0; i < subSimplex[j].size(); ++i) {
tempWeightedSumOver += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(overMap[i]);
tempWeightedSumUnder += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(underMap[i]);
}
if (cc.isEqual(tempWeightedSumOver, tempWeightedSumUnder)) {
hintVector.push_back(tempWeightedSumOver);
} else {
hintVector.push_back(targetObservations.find(observation) != targetObservations.end() ? storm::utility::one<ValueType>()
: storm::utility::zero<ValueType>());
}
weightedSumOverMap[nextId] = tempWeightedSumOver;
weightedSumUnderMap[nextId] = tempWeightedSumUnder;
} else {
hintVector.push_back(targetObservations.find(observation) != targetObservations.end() ? storm::utility::one<ValueType>()
: storm::utility::zero<ValueType>());
}
beliefsToBeExpanded.push_back(nextId);
beliefStateMap.insert(bsmap_type::value_type(nextId, mdpStateId));
transitionInActionBelief[mdpStateId] = iter->second * lambdas[j];
++nextId;
++mdpStateId;
} else {
transitionInActionBelief[beliefStateMap.left.at(approxId)] = iter->second * lambdas[j];
}
}
}
}
if (computeRewards) {
actionRewardsInState[action] = getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
beliefList[currId]);
}
if (!transitionInActionBelief.empty()) {
transitionsInBelief.push_back(transitionInActionBelief);
}
}
if (computeRewards) {
beliefActionRewards.emplace(std::make_pair(currId, actionRewardsInState));
}
if (transitionsInBelief.empty()) {
std::map<uint64_t, ValueType> transitionInActionBelief;
transitionInActionBelief[beliefStateMap.left.at(currId)] = storm::utility::one<ValueType>();
transitionsInBelief.push_back(transitionInActionBelief);
}
mdpTransitions.push_back(transitionsInBelief);
}
}
expansionTimer.stop();
STORM_PRINT("Grid size: " << beliefGrid.size() << std::endl)
STORM_PRINT("Belief space expansion took " << expansionTimer << std::endl)
storm::models::sparse::StateLabeling mdpLabeling(mdpTransitions.size());
mdpLabeling.addLabel("init");
mdpLabeling.addLabel("target");
mdpLabeling.addLabelToState("init", beliefStateMap.left.at(initialBelief.id));
for (auto targetState : targetStates) {
mdpLabeling.addLabelToState("target", targetState);
}
storm::storage::sparse::ModelComponents<ValueType, RewardModelType> modelComponents(buildTransitionMatrix(mdpTransitions), mdpLabeling);
storm::models::sparse::Mdp<ValueType, RewardModelType> overApproxMdp(modelComponents);
if (computeRewards) {
storm::models::sparse::StandardRewardModel<ValueType> mdpRewardModel(boost::none, std::vector<ValueType>(modelComponents.transitionMatrix.getRowCount()));
for (auto const &iter : beliefStateMap.left) {
auto currentBelief = beliefList[iter.first];
auto representativeState = pomdp.getStatesWithObservation(currentBelief.observation).front();
for (uint64_t action = 0; action < overApproxMdp.getNumberOfChoices(iter.second); ++action) {
// Add the reward
mdpRewardModel.setStateActionReward(overApproxMdp.getChoiceIndex(storm::storage::StateActionPair(iter.second, action)),
getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
currentBelief));
}
}
overApproxMdp.addRewardModel("std", mdpRewardModel);
overApproxMdp.restrictRewardModels(std::set<std::string>({"std"}));
}
overApproxMdp.printModelInformationToStream(std::cout);
auto model = std::make_shared<storm::models::sparse::Mdp<ValueType, RewardModelType>>(overApproxMdp);
auto modelPtr = std::static_pointer_cast<storm::models::sparse::Model<ValueType, RewardModelType>>(model);
std::string propertyString = computeRewards ? "R" : "P";
propertyString += min ? "min" : "max";
propertyString += "=? [F \"target\"]";
std::vector<storm::jani::Property> propertyVector = storm::api::parseProperties(propertyString);
std::shared_ptr<storm::logic::Formula const> property = storm::api::extractFormulasFromProperties(propertyVector).front();
auto task = storm::api::createTask<ValueType>(property, false);
auto hint = storm::modelchecker::ExplicitModelCheckerHint<ValueType>();
hint.setResultHint(hintVector);
auto hintPtr = std::make_shared<storm::modelchecker::ExplicitModelCheckerHint<ValueType>>(hint);
task.setHint(hintPtr);
storm::utility::Stopwatch overApproxTimer(true);
std::unique_ptr<storm::modelchecker::CheckResult> res(storm::api::verifyWithSparseEngine<ValueType>(model, task));
overApproxTimer.stop();
STORM_LOG_ASSERT(res, "Result not exist.");
res->filter(storm::modelchecker::ExplicitQualitativeCheckResult(storm::storage::BitVector(overApproxMdp.getNumberOfStates(), true)));
auto overApproxResultMap = res->asExplicitQuantitativeCheckResult<ValueType>().getValueMap();
auto overApprox = overApproxResultMap[beliefStateMap.left.at(initialBelief.id)];
STORM_PRINT("Time Overapproximation: " << overApproxTimer << std::endl)
//auto underApprox = weightedSumUnderMap[initialBelief.id];
auto underApproxComponents = computeUnderapproximation(pomdp, beliefList, beliefIsTarget, targetObservations, initialBelief.id, min, computeRewards,
maxUaModelSize);
STORM_PRINT("Over-Approximation Result: " << overApprox << std::endl);
STORM_PRINT("Under-Approximation Result: " << underApproxComponents->underApproxValue << std::endl);
return std::make_unique<RefinementComponents<ValueType>>(
RefinementComponents<ValueType>{modelPtr, overApprox, underApproxComponents->underApproxValue, overApproxResultMap,
underApproxComponents->underApproxMap, beliefList, beliefGrid, beliefIsTarget, beliefStateMap,
underApproxComponents->underApproxBeliefStateMap, initialBelief.id});
}
template<typename ValueType, typename RewardModelType>
std::shared_ptr<RefinementComponents<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeRefinementStep(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
std::vector<uint64_t> &observationResolutionVector,
bool computeRewards, double explorationThreshold,
std::shared_ptr<RefinementComponents<ValueType>> refinementComponents,
std::set<uint32_t> changedObservations,
boost::optional<std::map<uint64_t, ValueType>> overApproximationMap,
boost::optional<std::map<uint64_t, ValueType>> underApproximationMap,
uint64_t maxUaModelSize) {
// Note that a persistent cache is not support by the current data structure. The resolution for the given belief also has to be stored somewhere to cache effectively
std::map<uint64_t, std::vector<std::map<uint64_t, ValueType>>> subSimplexCache;
std::map<uint64_t, std::vector<ValueType>> lambdaCache;
uint64_t nextBeliefId = refinementComponents->beliefList.size();
uint64_t nextStateId = refinementComponents->overApproxModelPtr->getNumberOfStates();
std::set<uint64_t> relevantStates;
for (auto const &iter : refinementComponents->overApproxBeliefStateMap.left) {
auto currentBelief = refinementComponents->beliefList[iter.first];
if (changedObservations.find(currentBelief.observation) != changedObservations.end()) {
relevantStates.insert(iter.second);
}
}
std::set<std::pair<uint64_t, uint64_t>> statesAndActionsToCheck;
for (uint64_t state = 0; state < refinementComponents->overApproxModelPtr->getNumberOfStates(); ++state) {
for (uint_fast64_t row = 0; row < refinementComponents->overApproxModelPtr->getTransitionMatrix().getRowGroupSize(state); ++row) {
for (typename storm::storage::SparseMatrix<ValueType>::const_iterator itEntry = refinementComponents->overApproxModelPtr->getTransitionMatrix().getRow(
state, row).begin();
itEntry != refinementComponents->overApproxModelPtr->getTransitionMatrix().getRow(state, row).end(); ++itEntry) {
if (relevantStates.find(itEntry->getColumn()) != relevantStates.end()) {
statesAndActionsToCheck.insert(std::make_pair(state, row));
break;
}
}
}
}
std::deque<uint64_t> beliefsToBeExpanded;
std::map<std::pair<uint64_t, uint64_t>, std::map<uint64_t, ValueType>> transitionsStateActionPair;
for (auto const &stateActionPair : statesAndActionsToCheck) {
auto currId = refinementComponents->overApproxBeliefStateMap.right.at(stateActionPair.first);
auto action = stateActionPair.second;
std::map<uint32_t, ValueType> actionObservationProbabilities = computeObservationProbabilitiesAfterAction(pomdp, refinementComponents->beliefList[currId],
action);
std::map<uint64_t, ValueType> transitionInActionBelief;
for (auto iter = actionObservationProbabilities.begin(); iter != actionObservationProbabilities.end(); ++iter) {
uint32_t observation = iter->first;
uint64_t idNextBelief = getBeliefAfterActionAndObservation(pomdp, refinementComponents->beliefList, refinementComponents->beliefIsTarget,
targetObservations, refinementComponents->beliefList[currId], action, observation, nextBeliefId);
nextBeliefId = refinementComponents->beliefList.size();
//Triangulate here and put the possibly resulting belief in the grid
std::vector<std::map<uint64_t, ValueType>> subSimplex;
std::vector<ValueType> lambdas;
//TODO add caching
if (cacheSubsimplices && subSimplexCache.count(idNextBelief) > 0) {
subSimplex = subSimplexCache[idNextBelief];
lambdas = lambdaCache[idNextBelief];
} else {
auto temp = computeSubSimplexAndLambdas(refinementComponents->beliefList[idNextBelief].probabilities,
observationResolutionVector[refinementComponents->beliefList[idNextBelief].observation],
pomdp.getNumberOfStates());
subSimplex = temp.first;
lambdas = temp.second;
if (cacheSubsimplices) {
subSimplexCache[idNextBelief] = subSimplex;
lambdaCache[idNextBelief] = lambdas;
}
}
for (size_t j = 0; j < lambdas.size(); ++j) {
if (!cc.isEqual(lambdas[j], storm::utility::zero<ValueType>())) {
auto approxId = getBeliefIdInVector(refinementComponents->beliefGrid, observation, subSimplex[j]);
if (approxId == uint64_t(-1)) {
// if the triangulated belief was not found in the list, we place it in the grid and add it to the work list
storm::pomdp::Belief<ValueType> gridBelief = {nextBeliefId, observation, subSimplex[j]};
refinementComponents->beliefList.push_back(gridBelief);
refinementComponents->beliefGrid.push_back(gridBelief);
refinementComponents->beliefIsTarget.push_back(targetObservations.find(observation) != targetObservations.end());
// compute overapproximate value using MDP result map
//TODO do this
/*
if (boundMapsSet) {
auto tempWeightedSumOver = storm::utility::zero<ValueType>();
auto tempWeightedSumUnder = storm::utility::zero<ValueType>();
for (uint64_t i = 0; i < subSimplex[j].size(); ++i) {
tempWeightedSumOver += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(overMap[i]);
tempWeightedSumUnder += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(underMap[i]);
}
weightedSumOverMap[nextId] = tempWeightedSumOver;
weightedSumUnderMap[nextId] = tempWeightedSumUnder;
} */
beliefsToBeExpanded.push_back(nextBeliefId);
refinementComponents->overApproxBeliefStateMap.insert(bsmap_type::value_type(nextBeliefId, nextStateId));
transitionInActionBelief[nextStateId] = iter->second * lambdas[j];
++nextBeliefId;
++nextStateId;
} else {
transitionInActionBelief[refinementComponents->overApproxBeliefStateMap.left.at(approxId)] = iter->second * lambdas[j];
}
}
}
}
/* TODO
if (computeRewards) {
actionRewardsInState[action] = getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
refinementComponents->beliefList[currId]);
}*/
if (!transitionInActionBelief.empty()) {
transitionsStateActionPair[stateActionPair] = transitionInActionBelief;
}
}
// Expand newly added beliefs
while (!beliefsToBeExpanded.empty()) {
uint64_t currId = beliefsToBeExpanded.front();
beliefsToBeExpanded.pop_front();
bool isTarget = refinementComponents->beliefIsTarget[currId];
/* TODO
if (boundMapsSet && cc.isLess(weightedSumOverMap[currId] - weightedSumUnderMap[currId], storm::utility::convertNumber<ValueType>(explorationThreshold))) {
mdpTransitions.push_back({{{1, weightedSumOverMap[currId]}, {0, storm::utility::one<ValueType>() - weightedSumOverMap[currId]}}});
continue;
}*/
if (isTarget) {
// Depending on whether we compute rewards, we select the right initial result
// MDP stuff
transitionsStateActionPair[std::make_pair(refinementComponents->overApproxBeliefStateMap.left.at(currId), 0)] =
{{refinementComponents->overApproxBeliefStateMap.left.at(currId), storm::utility::one<ValueType>()}};
} else {
uint64_t representativeState = pomdp.getStatesWithObservation(refinementComponents->beliefList[currId].observation).front();
uint64_t numChoices = pomdp.getNumberOfChoices(representativeState);
std::vector<ValueType> actionRewardsInState(numChoices);
for (uint64_t action = 0; action < numChoices; ++action) {
std::map<uint32_t, ValueType> actionObservationProbabilities = computeObservationProbabilitiesAfterAction(pomdp,
refinementComponents->beliefList[currId],
action);
std::map<uint64_t, ValueType> transitionInActionBelief;
for (auto iter = actionObservationProbabilities.begin(); iter != actionObservationProbabilities.end(); ++iter) {
uint32_t observation = iter->first;
// THIS CALL IS SLOW
// TODO speed this up
uint64_t idNextBelief = getBeliefAfterActionAndObservation(pomdp, refinementComponents->beliefList, refinementComponents->beliefIsTarget,
targetObservations, refinementComponents->beliefList[currId], action, observation,
nextBeliefId);
nextBeliefId = refinementComponents->beliefList.size();
//Triangulate here and put the possibly resulting belief in the grid
std::vector<std::map<uint64_t, ValueType>> subSimplex;
std::vector<ValueType> lambdas;
/* TODO Caching
if (cacheSubsimplices && subSimplexCache.count(idNextBelief) > 0) {
subSimplex = subSimplexCache[idNextBelief];
lambdas = lambdaCache[idNextBelief];
} else { */
auto temp = computeSubSimplexAndLambdas(refinementComponents->beliefList[idNextBelief].probabilities,
observationResolutionVector[refinementComponents->beliefList[idNextBelief].observation],
pomdp.getNumberOfStates());
subSimplex = temp.first;
lambdas = temp.second;
/*if (cacheSubsimplices) {
subSimplexCache[idNextBelief] = subSimplex;
lambdaCache[idNextBelief] = lambdas;
}
}*/
for (size_t j = 0; j < lambdas.size(); ++j) {
if (!cc.isEqual(lambdas[j], storm::utility::zero<ValueType>())) {
auto approxId = getBeliefIdInVector(refinementComponents->beliefGrid, observation, subSimplex[j]);
if (approxId == uint64_t(-1)) {
// if the triangulated belief was not found in the list, we place it in the grid and add it to the work list
storm::pomdp::Belief<ValueType> gridBelief = {nextBeliefId, observation, subSimplex[j]};
refinementComponents->beliefList.push_back(gridBelief);
refinementComponents->beliefGrid.push_back(gridBelief);
refinementComponents->beliefIsTarget.push_back(targetObservations.find(observation) != targetObservations.end());
// compute overapproximate value using MDP result map
/*
if (boundMapsSet) {
auto tempWeightedSumOver = storm::utility::zero<ValueType>();
auto tempWeightedSumUnder = storm::utility::zero<ValueType>();
for (uint64_t i = 0; i < subSimplex[j].size(); ++i) {
tempWeightedSumOver += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(overMap[i]);
tempWeightedSumUnder += subSimplex[j][i] * storm::utility::convertNumber<ValueType>(underMap[i]);
}
weightedSumOverMap[nextId] = tempWeightedSumOver;
weightedSumUnderMap[nextId] = tempWeightedSumUnder;
} */
beliefsToBeExpanded.push_back(nextBeliefId);
refinementComponents->overApproxBeliefStateMap.insert(bsmap_type::value_type(nextBeliefId, nextStateId));
transitionInActionBelief[nextStateId] = iter->second * lambdas[j];
++nextBeliefId;
++nextStateId;
} else {
transitionInActionBelief[refinementComponents->overApproxBeliefStateMap.left.at(approxId)] = iter->second * lambdas[j];
}
}
}
}
/*
if (computeRewards) {
actionRewardsInState[action] = getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
beliefList[currId]);
}*/
if (!transitionInActionBelief.empty()) {
transitionsStateActionPair[std::make_pair(refinementComponents->overApproxBeliefStateMap.left.at(currId), action)] = transitionInActionBelief;
}
}
/*
if (computeRewards) {
beliefActionRewards.emplace(std::make_pair(currId, actionRewardsInState));
}
if (transitionsInBelief.empty()) {
std::map<uint64_t, ValueType> transitionInActionBelief;
transitionInActionBelief[beliefStateMap.left.at(currId)] = storm::utility::one<ValueType>();
transitionsInBelief.push_back(transitionInActionBelief);
}
mdpTransitions.push_back(transitionsInBelief);*/
}
}
storm::models::sparse::StateLabeling mdpLabeling(nextStateId);
mdpLabeling.addLabel("init");
mdpLabeling.addLabel("target");
mdpLabeling.addLabelToState("init", refinementComponents->overApproxBeliefStateMap.left.at(refinementComponents->initialBeliefId));
uint_fast64_t currentRow = 0;
uint_fast64_t currentRowGroup = 0;
storm::storage::SparseMatrixBuilder<ValueType> smb(0, nextStateId, 0, false, true);
auto oldTransitionMatrix = refinementComponents->overApproxModelPtr->getTransitionMatrix();
smb.newRowGroup(currentRow);
smb.addNextValue(currentRow, 0, storm::utility::one<ValueType>());
++currentRow;
++currentRowGroup;
smb.newRowGroup(currentRow);
smb.addNextValue(currentRow, 1, storm::utility::one<ValueType>());
++currentRow;
++currentRowGroup;
for (uint64_t state = 2; state < nextStateId; ++state) {
smb.newRowGroup(currentRow);
//STORM_PRINT("Loop State: " << state << std::endl)
uint64_t numChoices = pomdp.getNumberOfChoices(
pomdp.getStatesWithObservation(refinementComponents->beliefList[refinementComponents->overApproxBeliefStateMap.right.at(state)].observation).front());
bool isTarget = refinementComponents->beliefIsTarget[refinementComponents->overApproxBeliefStateMap.right.at(state)];
for (uint64_t action = 0; action < numChoices; ++action) {
if (transitionsStateActionPair.find(std::make_pair(state, action)) == transitionsStateActionPair.end()) {
for (auto const &entry : oldTransitionMatrix.getRow(state, action)) {
smb.addNextValue(currentRow, entry.getColumn(), entry.getValue());
}
} else {
for (auto const &iter : transitionsStateActionPair[std::make_pair(state, action)]) {
smb.addNextValue(currentRow, iter.first, iter.second);
}
}
++currentRow;
if (isTarget) {
// If the state is a target, we only have one action, thus we add the target label and stop the iteration
mdpLabeling.addLabelToState("target", state);
break;
}
}
++currentRowGroup;
}
storm::storage::sparse::ModelComponents<ValueType, RewardModelType> modelComponents(smb.build(), mdpLabeling);
storm::models::sparse::Mdp<ValueType, RewardModelType> overApproxMdp(modelComponents);
overApproxMdp.printModelInformationToStream(std::cout);
auto model = std::make_shared<storm::models::sparse::Mdp<ValueType, RewardModelType>>(overApproxMdp);
auto modelPtr = std::static_pointer_cast<storm::models::sparse::Model<ValueType, RewardModelType>>(model);
std::string propertyString = computeRewards ? "R" : "P";
propertyString += min ? "min" : "max";
propertyString += "=? [F \"target\"]";
std::vector<storm::jani::Property> propertyVector = storm::api::parseProperties(propertyString);
std::shared_ptr<storm::logic::Formula const> property = storm::api::extractFormulasFromProperties(propertyVector).front();
auto task = storm::api::createTask<ValueType>(property, false);
storm::utility::Stopwatch overApproxTimer(true);
std::unique_ptr<storm::modelchecker::CheckResult> res(storm::api::verifyWithSparseEngine<ValueType>(model, task));
overApproxTimer.stop();
STORM_LOG_ASSERT(res, "Result not exist.");
res->filter(storm::modelchecker::ExplicitQualitativeCheckResult(storm::storage::BitVector(overApproxMdp.getNumberOfStates(), true)));
auto overApproxResultMap = res->asExplicitQuantitativeCheckResult<ValueType>().getValueMap();
auto overApprox = overApproxResultMap[refinementComponents->overApproxBeliefStateMap.left.at(refinementComponents->initialBeliefId)];
STORM_PRINT("Time Overapproximation: " << overApproxTimer << std::endl)
//auto underApprox = weightedSumUnderMap[initialBelief.id];
auto underApproxComponents = computeUnderapproximation(pomdp, refinementComponents->beliefList, refinementComponents->beliefIsTarget, targetObservations,
refinementComponents->initialBeliefId, min, computeRewards, maxUaModelSize);
STORM_PRINT("Over-Approximation Result: " << overApprox << std::endl);
STORM_PRINT("Under-Approximation Result: " << underApproxComponents->underApproxValue << std::endl);
return std::make_shared<RefinementComponents<ValueType>>(
RefinementComponents<ValueType>{modelPtr, overApprox, underApproxComponents->underApproxValue, overApproxResultMap,
underApproxComponents->underApproxMap, refinementComponents->beliefList, refinementComponents->beliefGrid,
refinementComponents->beliefIsTarget,
refinementComponents->overApproxBeliefStateMap, underApproxComponents->underApproxBeliefStateMap});
}
template<typename ValueType, typename RewardModelType>
ValueType
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::overApproximationValueIteration(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::vector<storm::pomdp::Belief<ValueType>> &beliefList,
std::vector<storm::pomdp::Belief<ValueType>> &beliefGrid,
std::vector<bool> &beliefIsTarget,
std::map<uint64_t, std::vector<std::map<uint32_t, ValueType>>> &observationProbabilities,
std::map<uint64_t, std::vector<std::map<uint32_t, uint64_t>>> &nextBelieves,
std::map<uint64_t, std::vector<ValueType>> &beliefActionRewards,
std::map<uint64_t, std::vector<std::map<uint64_t, ValueType>>> &subSimplexCache,
std::map<uint64_t, std::vector<ValueType>> &lambdaCache,
std::map<uint64_t, ValueType> &result,
std::map<uint64_t, std::vector<uint64_t>> &chosenActions,
uint64_t gridResolution, bool min, bool computeRewards) {
std::map<uint64_t, ValueType> result_backup = result;
uint64_t iteration = 0;
bool finished = false;
// Value Iteration
while (!finished && iteration < maxIterations) {
storm::utility::Stopwatch iterationTimer(true);
STORM_LOG_DEBUG("Iteration " << iteration + 1);
bool improvement = false;
for (size_t i = 0; i < beliefGrid.size(); ++i) {
storm::pomdp::Belief<ValueType> currentBelief = beliefGrid[i];
bool isTarget = beliefIsTarget[currentBelief.id];
if (!isTarget) {
// we can take any state with the observation as they have the same number of choices
uint64_t numChoices = pomdp.getNumberOfChoices(pomdp.getStatesWithObservation(currentBelief.observation).front());
// Initialize the values for the value iteration
ValueType chosenValue = min ? storm::utility::infinity<ValueType>() : -storm::utility::infinity<ValueType>();
std::vector<uint64_t> chosenActionIndices;
ValueType currentValue;
for (uint64_t action = 0; action < numChoices; ++action) {
currentValue = computeRewards ? beliefActionRewards[currentBelief.id][action] : storm::utility::zero<ValueType>();
for (auto iter = observationProbabilities[currentBelief.id][action].begin();
iter != observationProbabilities[currentBelief.id][action].end(); ++iter) {
uint32_t observation = iter->first;
storm::pomdp::Belief<ValueType> nextBelief = beliefList[nextBelieves[currentBelief.id][action][observation]];
// compute subsimplex and lambdas according to the Lovejoy paper to approximate the next belief
// cache the values to not always re-calculate
std::vector<std::map<uint64_t, ValueType>> subSimplex;
std::vector<ValueType> lambdas;
if (cacheSubsimplices && subSimplexCache.count(nextBelief.id) > 0) {
subSimplex = subSimplexCache[nextBelief.id];
lambdas = lambdaCache[nextBelief.id];
} else {
auto temp = computeSubSimplexAndLambdas(nextBelief.probabilities, gridResolution, pomdp.getNumberOfStates());
subSimplex = temp.first;
lambdas = temp.second;
if (cacheSubsimplices) {
subSimplexCache[nextBelief.id] = subSimplex;
lambdaCache[nextBelief.id] = lambdas;
}
}
auto sum = storm::utility::zero<ValueType>();
for (size_t j = 0; j < lambdas.size(); ++j) {
if (!cc.isEqual(lambdas[j], storm::utility::zero<ValueType>())) {
sum += lambdas[j] * result_backup.at(getBeliefIdInVector(beliefGrid, observation, subSimplex[j]));
}
}
currentValue += iter->second * sum;
}
// Update the selected actions
if ((min && cc.isLess(storm::utility::zero<ValueType>(), chosenValue - currentValue)) ||
(!min && cc.isLess(storm::utility::zero<ValueType>(), currentValue - chosenValue)) ||
cc.isEqual(storm::utility::zero<ValueType>(), chosenValue - currentValue)) {
chosenValue = currentValue;
if (!(useMdp && cc.isEqual(storm::utility::zero<ValueType>(), chosenValue - currentValue))) {
chosenActionIndices.clear();
}
chosenActionIndices.push_back(action);
}
}
result[currentBelief.id] = chosenValue;
chosenActions[currentBelief.id] = chosenActionIndices;
// Check if the iteration brought an improvement
if (!cc.isEqual(result_backup[currentBelief.id], result[currentBelief.id])) {
improvement = true;
}
}
}
finished = !improvement;
// back up
result_backup = result;
++iteration;
iterationTimer.stop();
STORM_PRINT("Iteration " << iteration << ": " << iterationTimer << std::endl);
}
STORM_PRINT("Overapproximation took " << iteration << " iterations" << std::endl);
std::vector<ValueType> initialLambda;
std::vector<std::map<uint64_t, ValueType>> initialSubsimplex;
if (cacheSubsimplices) {
initialLambda = lambdaCache[0];
initialSubsimplex = subSimplexCache[0];
} else {
auto temp = computeSubSimplexAndLambdas(beliefList[0].probabilities, gridResolution, pomdp.getNumberOfStates());
initialSubsimplex = temp.first;
initialLambda = temp.second;
}
auto overApprox = storm::utility::zero<ValueType>();
for (size_t j = 0; j < initialLambda.size(); ++j) {
if (initialLambda[j] != storm::utility::zero<ValueType>()) {
overApprox += initialLambda[j] * result_backup[getBeliefIdInVector(beliefGrid, beliefList[0].observation, initialSubsimplex[j])];
}
}
return overApprox;
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachabilityRewardOTF(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
uint64_t gridResolution) {
std::vector<uint64_t> observationResolutionVector(pomdp.getNrObservations(), gridResolution);
return computeReachabilityOTF(pomdp, targetObservations, min, observationResolutionVector, true, 0);
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachabilityProbabilityOTF(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
uint64_t gridResolution, double explorationThreshold) {
std::vector<uint64_t> observationResolutionVector(pomdp.getNrObservations(), gridResolution);
return computeReachabilityOTF(pomdp, targetObservations, min, observationResolutionVector, false, explorationThreshold);
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachability(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min, uint64_t gridResolution,
bool computeRewards) {
storm::utility::Stopwatch beliefGridTimer(true);
std::vector<storm::pomdp::Belief<ValueType>> beliefList;
std::vector<bool> beliefIsTarget;
uint64_t nextId = 0;
// Initial belief always has ID 0
storm::pomdp::Belief<ValueType> initialBelief = getInitialBelief(pomdp, nextId);
++nextId;
beliefList.push_back(initialBelief);
beliefIsTarget.push_back(targetObservations.find(initialBelief.observation) != targetObservations.end());
std::vector<storm::pomdp::Belief<ValueType>> beliefGrid;
constructBeliefGrid(pomdp, targetObservations, gridResolution, beliefList, beliefGrid, beliefIsTarget, nextId);
nextId = beliefList.size();
beliefGridTimer.stop();
storm::utility::Stopwatch overApproxTimer(true);
// Belief ID -> Value
std::map<uint64_t, ValueType> result;
// Belief ID -> ActionIndex
std::map<uint64_t, std::vector<uint64_t>> chosenActions;
// Belief ID -> action -> Observation -> Probability
std::map<uint64_t, std::vector<std::map<uint32_t, ValueType>>> observationProbabilities;
// current ID -> action -> next ID
std::map<uint64_t, std::vector<std::map<uint32_t, uint64_t>>> nextBelieves;
// current ID -> action -> reward
std::map<uint64_t, std::vector<ValueType>> beliefActionRewards;
//Use caching to avoid multiple computation of the subsimplices and lambdas
std::map<uint64_t, std::vector<std::map<uint64_t, ValueType>>> subSimplexCache;
std::map<uint64_t, std::vector<ValueType>> lambdaCache;
auto temp = computeSubSimplexAndLambdas(initialBelief.probabilities, gridResolution, pomdp.getNumberOfStates());
if (cacheSubsimplices) {
subSimplexCache[0] = temp.first;
lambdaCache[0] = temp.second;
}
storm::utility::Stopwatch nextBeliefGeneration(true);
for (size_t i = 0; i < beliefGrid.size(); ++i) {
auto currentBelief = beliefGrid[i];
bool isTarget = beliefIsTarget[currentBelief.id];
if (isTarget) {
result.emplace(std::make_pair(currentBelief.id, computeRewards ? storm::utility::zero<ValueType>() : storm::utility::one<ValueType>()));
} else {
result.emplace(std::make_pair(currentBelief.id, storm::utility::zero<ValueType>()));
//TODO put this in extra function
// As we need to grab some parameters which are the same for all states with the same observation, we simply select some state as the representative
uint64_t representativeState = pomdp.getStatesWithObservation(currentBelief.observation).front();
uint64_t numChoices = pomdp.getNumberOfChoices(representativeState);
std::vector<std::map<uint32_t, ValueType>> observationProbabilitiesInAction(numChoices);
std::vector<std::map<uint32_t, uint64_t>> nextBelievesInAction(numChoices);
std::vector<ValueType> actionRewardsInState(numChoices);
for (uint64_t action = 0; action < numChoices; ++action) {
std::map<uint32_t, ValueType> actionObservationProbabilities = computeObservationProbabilitiesAfterAction(pomdp, currentBelief, action);
std::map<uint32_t, uint64_t> actionObservationBelieves;
for (auto iter = actionObservationProbabilities.begin(); iter != actionObservationProbabilities.end(); ++iter) {
uint32_t observation = iter->first;
// THIS CALL IS SLOW
// TODO speed this up
actionObservationBelieves[observation] = getBeliefAfterActionAndObservation(pomdp, beliefList, beliefIsTarget, targetObservations, currentBelief,
action, observation, nextId);
nextId = beliefList.size();
}
observationProbabilitiesInAction[action] = actionObservationProbabilities;
nextBelievesInAction[action] = actionObservationBelieves;
if (computeRewards) {
actionRewardsInState[action] = getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
currentBelief);
}
}
observationProbabilities.emplace(std::make_pair(currentBelief.id, observationProbabilitiesInAction));
nextBelieves.emplace(std::make_pair(currentBelief.id, nextBelievesInAction));
if (computeRewards) {
beliefActionRewards.emplace(std::make_pair(currentBelief.id, actionRewardsInState));
}
}
}
nextBeliefGeneration.stop();
STORM_PRINT("Time generation of next believes: " << nextBeliefGeneration << std::endl)
// Value Iteration
auto overApprox = overApproximationValueIteration(pomdp, beliefList, beliefGrid, beliefIsTarget, observationProbabilities, nextBelieves, beliefActionRewards,
subSimplexCache, lambdaCache,
result, chosenActions, gridResolution, min, computeRewards);
overApproxTimer.stop();
// Now onto the under-approximation
storm::utility::Stopwatch underApproxTimer(true);
/*ValueType underApprox = computeUnderapproximation(pomdp, beliefList, beliefIsTarget, targetObservations, observationProbabilities, nextBelieves,
result, chosenActions, gridResolution, initialBelief.id, min, computeRewards, useMdp);*/
underApproxTimer.stop();
auto underApprox = storm::utility::zero<ValueType>();
STORM_PRINT("Time Belief Grid Generation: " << beliefGridTimer << std::endl
<< "Time Overapproximation: " << overApproxTimer
<< std::endl
<< "Time Underapproximation: " << underApproxTimer
<< std::endl);
STORM_PRINT("Over-Approximation Result: " << overApprox << std::endl);
STORM_PRINT("Under-Approximation Result: " << underApprox << std::endl);
return std::make_unique<POMDPCheckResult<ValueType>>(POMDPCheckResult<ValueType>{overApprox, underApprox});
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachabilityProbability(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
uint64_t gridResolution) {
return computeReachability(pomdp, targetObservations, min, gridResolution, false);
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<POMDPCheckResult<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeReachabilityReward(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &targetObservations, bool min,
uint64_t gridResolution) {
return computeReachability(pomdp, targetObservations, min, gridResolution, true);
}
template<typename ValueType, typename RewardModelType>
std::unique_ptr<UnderApproxComponents<ValueType, RewardModelType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeUnderapproximation(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::vector<storm::pomdp::Belief<ValueType>> &beliefList,
std::vector<bool> &beliefIsTarget,
std::set<uint32_t> const &targetObservations,
uint64_t initialBeliefId, bool min,
bool computeRewards, uint64_t maxModelSize) {
std::set<uint64_t> visitedBelieves;
std::deque<uint64_t> believesToBeExpanded;
bsmap_type beliefStateMap;
std::vector<std::vector<std::map<uint64_t, ValueType>>> transitions = {{{{0, storm::utility::one<ValueType>()}}},
{{{1, storm::utility::one<ValueType>()}}}};
std::vector<uint64_t> targetStates = {1};
uint64_t stateId = 2;
beliefStateMap.insert(bsmap_type::value_type(initialBeliefId, stateId));
++stateId;
uint64_t nextId = beliefList.size();
uint64_t counter = 0;
// Expand the believes
visitedBelieves.insert(initialBeliefId);
believesToBeExpanded.push_back(initialBeliefId);
while (!believesToBeExpanded.empty()) {
//TODO think of other ways to stop exploration besides model size
auto currentBeliefId = believesToBeExpanded.front();
uint64_t numChoices = pomdp.getNumberOfChoices(pomdp.getStatesWithObservation(beliefList[currentBeliefId].observation).front());
// for targets, we only consider one action with one transition
if (beliefIsTarget[currentBeliefId]) {
// add a self-loop to target states
targetStates.push_back(beliefStateMap.left.at(currentBeliefId));
transitions.push_back({{{beliefStateMap.left.at(currentBeliefId), storm::utility::one<ValueType>()}}});
} else if (counter > maxModelSize) {
transitions.push_back({{{0, storm::utility::one<ValueType>()}}});
} else {
// Iterate over all actions and add the corresponding transitions
std::vector<std::map<uint64_t, ValueType>> actionTransitionStorage;
//TODO add a way to extract the actions from the over-approx and use them here?
for (uint64_t action = 0; action < numChoices; ++action) {
std::map<uint64_t, ValueType> transitionsInStateWithAction;
std::map<uint32_t, ValueType> observationProbabilities = computeObservationProbabilitiesAfterAction(pomdp, beliefList[currentBeliefId], action);
for (auto iter = observationProbabilities.begin(); iter != observationProbabilities.end(); ++iter) {
uint32_t observation = iter->first;
uint64_t nextBeliefId = getBeliefAfterActionAndObservation(pomdp, beliefList, beliefIsTarget, targetObservations, beliefList[currentBeliefId],
action,
observation, nextId);
nextId = beliefList.size();
if (visitedBelieves.insert(nextBeliefId).second) {
beliefStateMap.insert(bsmap_type::value_type(nextBeliefId, stateId));
++stateId;
believesToBeExpanded.push_back(nextBeliefId);
++counter;
}
transitionsInStateWithAction[beliefStateMap.left.at(nextBeliefId)] = iter->second;
}
actionTransitionStorage.push_back(transitionsInStateWithAction);
}
transitions.push_back(actionTransitionStorage);
}
believesToBeExpanded.pop_front();
}
storm::models::sparse::StateLabeling labeling(transitions.size());
labeling.addLabel("init");
labeling.addLabel("target");
labeling.addLabelToState("init", 0);
for (auto targetState : targetStates) {
labeling.addLabelToState("target", targetState);
}
std::shared_ptr<storm::models::sparse::Model<ValueType, RewardModelType>> model;
auto transitionMatrix = buildTransitionMatrix(transitions);
if (transitionMatrix.getRowCount() == transitionMatrix.getRowGroupCount()) {
transitionMatrix.makeRowGroupingTrivial();
}
storm::storage::sparse::ModelComponents<ValueType, RewardModelType> modelComponents(transitionMatrix, labeling);
storm::models::sparse::Mdp<ValueType, RewardModelType> underApproxMdp(modelComponents);
if (computeRewards) {
storm::models::sparse::StandardRewardModel<ValueType> rewardModel(boost::none, std::vector<ValueType>(modelComponents.transitionMatrix.getRowCount()));
for (auto const &iter : beliefStateMap.left) {
auto currentBelief = beliefList[iter.first];
auto representativeState = pomdp.getStatesWithObservation(currentBelief.observation).front();
for (uint64_t action = 0; action < underApproxMdp.getNumberOfChoices(iter.second); ++action) {
// Add the reward
rewardModel.setStateActionReward(underApproxMdp.getChoiceIndex(storm::storage::StateActionPair(iter.second, action)),
getRewardAfterAction(pomdp, pomdp.getChoiceIndex(storm::storage::StateActionPair(representativeState, action)),
currentBelief));
}
}
underApproxMdp.addRewardModel("std", rewardModel);
underApproxMdp.restrictRewardModels(std::set<std::string>({"std"}));
}
model = std::make_shared<storm::models::sparse::Mdp<ValueType, RewardModelType>>(underApproxMdp);
model->printModelInformationToStream(std::cout);
std::string propertyString;
if (computeRewards) {
propertyString = min ? "Rmin=? [F \"target\"]" : "Rmax=? [F \"target\"]";
} else {
propertyString = min ? "Pmin=? [F \"target\"]" : "Pmax=? [F \"target\"]";
}
std::vector<storm::jani::Property> propertyVector = storm::api::parseProperties(propertyString);
std::shared_ptr<storm::logic::Formula const> property = storm::api::extractFormulasFromProperties(propertyVector).front();
std::unique_ptr<storm::modelchecker::CheckResult> res(storm::api::verifyWithSparseEngine<ValueType>(model, storm::api::createTask<ValueType>(property, false)));
STORM_LOG_ASSERT(res, "Result does not exist.");
res->filter(storm::modelchecker::ExplicitQualitativeCheckResult(storm::storage::BitVector(underApproxMdp.getNumberOfStates(), true)));
auto underApproxResultMap = res->asExplicitQuantitativeCheckResult<ValueType>().getValueMap();
auto underApprox = underApproxResultMap[beliefStateMap.left.at(initialBeliefId)];
return std::make_unique<UnderApproxComponents<ValueType>>(UnderApproxComponents<ValueType>{underApprox, underApproxResultMap, beliefStateMap});
}
template<typename ValueType, typename RewardModelType>
storm::storage::SparseMatrix<ValueType>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::buildTransitionMatrix(std::vector<std::vector<std::map<uint64_t, ValueType>>> &transitions) {
uint_fast64_t currentRow = 0;
uint_fast64_t currentRowGroup = 0;
uint64_t nrColumns = transitions.size();
uint64_t nrRows = 0;
uint64_t nrEntries = 0;
for (auto const &actionTransitions : transitions) {
for (auto const &map : actionTransitions) {
nrEntries += map.size();
++nrRows;
}
}
storm::storage::SparseMatrixBuilder<ValueType> smb(nrRows, nrColumns, nrEntries, true, true);
for (auto const &actionTransitions : transitions) {
smb.newRowGroup(currentRow);
for (auto const &map : actionTransitions) {
for (auto const &transition : map) {
smb.addNextValue(currentRow, transition.first, transition.second);
}
++currentRow;
}
++currentRowGroup;
}
return smb.build();
}
template<typename ValueType, typename RewardModelType>
uint64_t ApproximatePOMDPModelchecker<ValueType, RewardModelType>::getBeliefIdInVector(
std::vector<storm::pomdp::Belief<ValueType>> const &grid, uint32_t observation,
std::map<uint64_t, ValueType> &probabilities) {
// TODO This one is quite slow
for (auto const &belief : grid) {
if (belief.observation == observation) {
bool same = true;
for (auto const &probEntry : belief.probabilities) {
if (probabilities.find(probEntry.first) == probabilities.end()) {
same = false;
break;
}
if (!cc.isEqual(probEntry.second, probabilities[probEntry.first])) {
same = false;
break;
}
}
if (same) {
return belief.id;
}
}
}
return -1;
}
template<typename ValueType, typename RewardModelType>
storm::pomdp::Belief<ValueType> ApproximatePOMDPModelchecker<ValueType, RewardModelType>::getInitialBelief(
storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp, uint64_t id) {
STORM_LOG_ASSERT(pomdp.getInitialStates().getNumberOfSetBits() < 2,
"POMDP contains more than one initial state");
STORM_LOG_ASSERT(pomdp.getInitialStates().getNumberOfSetBits() == 1,
"POMDP does not contain an initial state");
std::map<uint64_t, ValueType> distribution;
uint32_t observation = 0;
for (uint64_t state = 0; state < pomdp.getNumberOfStates(); ++state) {
if (pomdp.getInitialStates()[state] == 1) {
distribution[state] = storm::utility::one<ValueType>();
observation = pomdp.getObservation(state);
break;
}
}
return storm::pomdp::Belief<ValueType>{id, observation, distribution};
}
template<typename ValueType, typename RewardModelType>
void ApproximatePOMDPModelchecker<ValueType, RewardModelType>::constructBeliefGrid(
storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
std::set<uint32_t> const &target_observations, uint64_t gridResolution,
std::vector<storm::pomdp::Belief<ValueType>> &beliefList,
std::vector<storm::pomdp::Belief<ValueType>> &grid, std::vector<bool> &beliefIsTarget,
uint64_t nextId) {
bool isTarget;
uint64_t newId = nextId;
for (uint32_t observation = 0; observation < pomdp.getNrObservations(); ++observation) {
std::vector<uint64_t> statesWithObservation = pomdp.getStatesWithObservation(observation);
isTarget = target_observations.find(observation) != target_observations.end();
// TODO this can probably be condensed
if (statesWithObservation.size() == 1) {
// If there is only one state with the observation, we can directly add the corresponding belief
std::map<uint64_t, ValueType> distribution;
distribution[statesWithObservation.front()] = storm::utility::one<ValueType>();
storm::pomdp::Belief<ValueType> belief = {newId, observation, distribution};
STORM_LOG_TRACE(
"Add Belief " << std::to_string(newId) << " [(" << std::to_string(observation) << "),"
<< distribution << "]");
beliefList.push_back(belief);
grid.push_back(belief);
beliefIsTarget.push_back(isTarget);
++newId;
} else {
// Otherwise we have to enumerate all possible distributions with regards to the grid
// helper is used to derive the distribution of the belief
std::vector<ValueType> helper(statesWithObservation.size(), ValueType(0));
helper[0] = storm::utility::convertNumber<ValueType>(gridResolution);
bool done = false;
uint64_t index = 0;
while (!done) {
std::map<uint64_t, ValueType> distribution;
for (size_t i = 0; i < statesWithObservation.size() - 1; ++i) {
if (helper[i] - helper[i + 1] > ValueType(0)) {
distribution[statesWithObservation[i]] = (helper[i] - helper[i + 1]) /
storm::utility::convertNumber<ValueType>(
gridResolution);
}
}
if (helper[statesWithObservation.size() - 1] > ValueType(0)) {
distribution[statesWithObservation.back()] =
helper[statesWithObservation.size() - 1] /
storm::utility::convertNumber<ValueType>(gridResolution);
}
storm::pomdp::Belief<ValueType> belief = {newId, observation, distribution};
STORM_LOG_TRACE("Add Belief " << std::to_string(newId) << " [(" << std::to_string(observation) << ")," << distribution << "]");
beliefList.push_back(belief);
grid.push_back(belief);
beliefIsTarget.push_back(isTarget);
if (helper[statesWithObservation.size() - 1] ==
storm::utility::convertNumber<ValueType>(gridResolution)) {
// If the last entry of helper is the gridResolution, we have enumerated all necessary distributions
done = true;
} else {
// Update helper by finding the index to increment
index = statesWithObservation.size() - 1;
while (helper[index] == helper[index - 1]) {
--index;
}
STORM_LOG_ASSERT(index > 0, "Error in BeliefGrid generation - index wrong");
// Increment the value at the index
++helper[index];
// Reset all indices greater than the changed one to 0
++index;
while (index < statesWithObservation.size()) {
helper[index] = 0;
++index;
}
}
++newId;
}
}
}
}
template<typename ValueType, typename RewardModelType>
std::pair<std::vector<std::map<uint64_t, ValueType>>, std::vector<ValueType>>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeSubSimplexAndLambdas(
std::map<uint64_t, ValueType> &probabilities, uint64_t resolution, uint64_t nrStates) {
//TODO this can also be simplified using the sparse vector interpretation
// This is the Freudenthal Triangulation as described in Lovejoy (a whole lotta math)
// Variable names are based on the paper
std::vector<ValueType> x(nrStates);
std::vector<ValueType> v(nrStates);
std::vector<ValueType> d(nrStates);
auto convResolution = storm::utility::convertNumber<ValueType>(resolution);
for (size_t i = 0; i < nrStates; ++i) {
for (auto const &probEntry : probabilities) {
if (probEntry.first >= i) {
x[i] += convResolution * probEntry.second;
}
}
v[i] = storm::utility::floor(x[i]);
d[i] = x[i] - v[i];
}
auto p = storm::utility::vector::getSortedIndices(d);
std::vector<std::vector<ValueType>> qs(nrStates, std::vector<ValueType>(nrStates));
for (size_t i = 0; i < nrStates; ++i) {
if (i == 0) {
for (size_t j = 0; j < nrStates; ++j) {
qs[i][j] = v[j];
}
} else {
for (size_t j = 0; j < nrStates; ++j) {
if (j == p[i - 1]) {
qs[i][j] = qs[i - 1][j] + storm::utility::one<ValueType>();
} else {
qs[i][j] = qs[i - 1][j];
}
}
}
}
std::vector<std::map<uint64_t, ValueType>> subSimplex(nrStates);
for (size_t j = 0; j < nrStates; ++j) {
for (size_t i = 0; i < nrStates - 1; ++i) {
if (cc.isLess(storm::utility::zero<ValueType>(), qs[j][i] - qs[j][i + 1])) {
subSimplex[j][i] = (qs[j][i] - qs[j][i + 1]) / convResolution;
}
}
if (cc.isLess(storm::utility::zero<ValueType>(), qs[j][nrStates - 1])) {
subSimplex[j][nrStates - 1] = qs[j][nrStates - 1] / convResolution;
}
}
std::vector<ValueType> lambdas(nrStates, storm::utility::zero<ValueType>());
auto sum = storm::utility::zero<ValueType>();
for (size_t i = 1; i < nrStates; ++i) {
lambdas[i] = d[p[i - 1]] - d[p[i]];
sum += d[p[i - 1]] - d[p[i]];
}
lambdas[0] = storm::utility::one<ValueType>() - sum;
return std::make_pair(subSimplex, lambdas);
}
template<typename ValueType, typename RewardModelType>
std::map<uint32_t, ValueType>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::computeObservationProbabilitiesAfterAction(
storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
storm::pomdp::Belief<ValueType> &belief,
uint64_t actionIndex) {
std::map<uint32_t, ValueType> res;
// the id is not important here as we immediately discard the belief (very hacky, I don't like it either)
std::map<uint64_t, ValueType> postProbabilities;
for (auto const &probEntry : belief.probabilities) {
uint64_t state = probEntry.first;
auto row = pomdp.getTransitionMatrix().getRow(pomdp.getChoiceIndex(storm::storage::StateActionPair(state, actionIndex)));
for (auto const &entry : row) {
if (entry.getValue() > 0) {
postProbabilities[entry.getColumn()] += belief.probabilities[state] * entry.getValue();
}
}
}
for (auto const &probEntry : postProbabilities) {
uint32_t observation = pomdp.getObservation(probEntry.first);
if (res.count(observation) == 0) {
res[observation] = probEntry.second;
} else {
res[observation] += probEntry.second;
}
}
return res;
}
template<typename ValueType, typename RewardModelType>
storm::pomdp::Belief<ValueType>
ApproximatePOMDPModelchecker<ValueType, RewardModelType>::getBeliefAfterAction(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
storm::pomdp::Belief<ValueType> &belief, uint64_t actionIndex, uint64_t id) {
std::map<uint64_t, ValueType> distributionAfter;
uint32_t observation = 0;
for (auto const &probEntry : belief.probabilities) {
uint64_t state = probEntry.first;
auto row = pomdp.getTransitionMatrix().getRow(pomdp.getChoiceIndex(storm::storage::StateActionPair(state, actionIndex)));
for (auto const &entry : row) {
if (entry.getValue() > 0) {
observation = pomdp.getObservation(entry.getColumn());
distributionAfter[entry.getColumn()] += belief.probabilities[state] * entry.getValue();
}
}
}
return storm::pomdp::Belief<ValueType>{id, observation, distributionAfter};
}
template<typename ValueType, typename RewardModelType>
uint64_t ApproximatePOMDPModelchecker<ValueType, RewardModelType>::getBeliefAfterActionAndObservation(
storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp, std::vector<storm::pomdp::Belief<ValueType>> &beliefList,
std::vector<bool> &beliefIsTarget, std::set<uint32_t> const &targetObservations, storm::pomdp::Belief<ValueType> &belief, uint64_t actionIndex,
uint32_t observation, uint64_t id) {
std::map<uint64_t, ValueType> distributionAfter;
for (auto const &probEntry : belief.probabilities) {
uint64_t state = probEntry.first;
auto row = pomdp.getTransitionMatrix().getRow(pomdp.getChoiceIndex(storm::storage::StateActionPair(state, actionIndex)));
for (auto const &entry : row) {
if (pomdp.getObservation(entry.getColumn()) == observation) {
distributionAfter[entry.getColumn()] += belief.probabilities[state] * entry.getValue();
}
}
}
// We have to normalize the distribution
auto sum = storm::utility::zero<ValueType>();
for (auto const &entry : distributionAfter) {
sum += entry.second;
}
for (auto const &entry : distributionAfter) {
distributionAfter[entry.first] /= sum;
}
if (getBeliefIdInVector(beliefList, observation, distributionAfter) != uint64_t(-1)) {
auto res = getBeliefIdInVector(beliefList, observation, distributionAfter);
return res;
} else {
beliefList.push_back(storm::pomdp::Belief<ValueType>{id, observation, distributionAfter});
beliefIsTarget.push_back(targetObservations.find(observation) != targetObservations.end());
return id;
}
}
template<typename ValueType, typename RewardModelType>
ValueType ApproximatePOMDPModelchecker<ValueType, RewardModelType>::getRewardAfterAction(storm::models::sparse::Pomdp<ValueType, RewardModelType> const &pomdp,
uint64_t action, storm::pomdp::Belief<ValueType> &belief) {
auto result = storm::utility::zero<ValueType>();
for (size_t i = 0; i < belief.probabilities.size(); ++i) {
for (auto const &probEntry : belief.probabilities)
result += probEntry.second * pomdp.getUniqueRewardModel().getTotalStateActionReward(probEntry.first, action, pomdp.getTransitionMatrix());
}
return result;
}
template
class ApproximatePOMDPModelchecker<double>;
#ifdef STORM_HAVE_CARL
template
class ApproximatePOMDPModelchecker<storm::RationalNumber>;
#endif
}
}
}