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#pragma once
#include "storm/storage/BitVector.h"
#include "storm/storage/SparseMatrix.h"
#include "storm/storage/Scheduler.h"
#include "storm/transformer/EndComponentEliminator.h"
#include "storm/modelchecker/multiobjective/Objective.h"
#include "storm/modelchecker/multiobjective/pcaa/PcaaWeightVectorChecker.h"
#include "storm/modelchecker/multiobjective/SparseMultiObjectivePreprocessorResult.h"
#include "storm/utility/vector.h"
namespace storm {
namespace modelchecker {
namespace multiobjective {
/*!
* Helper Class that takes preprocessed Pcaa data and a weight vector and ...
* - computes the optimal expected reward w.r.t. the weighted sum of the rewards of the individual objectives
* - extracts the scheduler that induces this optimum
* - computes for each objective the value induced by this scheduler
*/
template <class SparseModelType>
class SparsePcaaWeightVectorChecker : public PcaaWeightVectorChecker<SparseModelType> {
public:
typedef typename SparseModelType::ValueType ValueType;
/*
* Creates a weight vextor checker.
*
* @param model The (preprocessed) model
* @param objectives The (preprocessed) objectives
* @param possibleECActions Overapproximation of the actions that are part of an EC
* @param possibleBottomStates The states for which it is posible to not collect further reward with prob. 1
*
*/
SparsePcaaWeightVectorChecker(SparseMultiObjectivePreprocessorResult<SparseModelType> const& preprocessorResult);
virtual ~SparsePcaaWeightVectorChecker() = default;
/*!
* - computes the optimal expected reward w.r.t. the weighted sum of the rewards of the individual objectives
* - extracts the scheduler that induces this optimum
* - computes for each objective the value induced by this scheduler
*/
virtual void check(std::vector<ValueType> const& weightVector) override;
/*!
* Retrieves the results of the individual objectives at the initial state of the given model.
* Note that check(..) has to be called before retrieving results. Otherwise, an exception is thrown.
* Also note that there is no guarantee that the under/over approximation is in fact correct
* as long as the underlying solution methods are unsound (e.g., standard value iteration).
*/
virtual std::vector<ValueType> getUnderApproximationOfInitialStateResults() const override;
virtual std::vector<ValueType> getOverApproximationOfInitialStateResults() const override;
/*!
* Retrieves a scheduler that induces the current values
* Note that check(..) has to be called before retrieving the scheduler. Otherwise, an exception is thrown.
* Also note that (currently) the scheduler only supports unbounded objectives.
*/
virtual storm::storage::Scheduler<ValueType> computeScheduler() const override;
protected:
void initialize(SparseMultiObjectivePreprocessorResult<SparseModelType> const& preprocessorResult);
virtual void initializeModelTypeSpecificData(SparseModelType const& model) = 0;
/*!
* Computes the weighted lower and upper bounds for the provided set of objectives.
* @param lower if true, lower result bounds are computed. otherwise upper result bounds
* @param weightVector the weight vector ooof the current check
*/
boost::optional<ValueType> computeWeightedResultBound(bool lower, std::vector<ValueType> const& weightVector, storm::storage::BitVector const& objectiveFilter) const;
/*!
* Determines the scheduler that optimizes the weighted reward vector of the unbounded objectives
*
* @param weightedRewardVector the weighted rewards (only considering the unbounded objectives)
*/
void unboundedWeightedPhase(std::vector<ValueType> const& weightedRewardVector, std::vector<ValueType> const& weightVector);
/*!
* Computes the values of the objectives that do not have a stepBound w.r.t. the scheduler computed in the unboundedWeightedPhase
*
*/
void unboundedIndividualPhase(std::vector<ValueType> const& weightVector);
/*!
* For each time epoch (starting with the maximal stepBound occurring in the objectives), this method
* - determines the objectives that are relevant in the current time epoch
* - determines the maximizing scheduler for the weighted reward vector of these objectives
* - computes the values of these objectives w.r.t. this scheduler
*
* @param weightVector the weight vector of the current check
* @param weightedRewardVector the weighted rewards considering the unbounded objectives. Will be invalidated after calling this.
*/
virtual void boundedPhase(std::vector<ValueType> const& weightVector, std::vector<ValueType>& weightedRewardVector) = 0;
void updateEcQuotient(std::vector<ValueType> const& weightedRewardVector);
/*!
* Transforms the results of a min-max-solver that considers a reduced model (without end components) to a result for the original (unreduced) model
*/
void transformReducedSolutionToOriginalModel(storm::storage::SparseMatrix<ValueType> const& reducedMatrix,
std::vector<ValueType> const& reducedSolution,
std::vector<uint_fast64_t> const& reducedOptimalChoices,
std::vector<uint_fast64_t> const& reducedToOriginalChoiceMapping,
std::vector<uint_fast64_t> const& originalToReducedStateMapping,
std::vector<ValueType>& originalSolution,
std::vector<uint_fast64_t>& originalOptimalChoices) const;
// Data regarding the given model
// The transition matrix of the considered model
storm::storage::SparseMatrix<ValueType> transitionMatrix;
// The initial state of the considered model
uint64_t initialState;
// Overapproximation of the set of choices that are part of an end component.
storm::storage::BitVector ecChoicesHint;
// The actions that have reward assigned for at least one objective without upper timeBound
storm::storage::BitVector actionsWithoutRewardInUnboundedPhase;
// The states for which there is a scheduler yielding reward 0 for each objective
storm::storage::BitVector reward0EStates;
// stores the state action rewards for each objective.
std::vector<std::vector<ValueType>> actionRewards;
// stores the indices of the objectives for which there is no upper time bound
storm::storage::BitVector objectivesWithNoUpperTimeBound;
// Memory for the solution of the most recent call of check(..)
// becomes true after the first call of check(..)
bool checkHasBeenCalled;
// The result for the weighted reward vector (for all states of the model)
std::vector<ValueType> weightedResult;
// The results for the individual objectives (w.r.t. all states of the model)
std::vector<std::vector<ValueType>> objectiveResults;
// Stores for each objective the distance between the computed result (w.r.t. the initial state) and an over/under approximation for the actual result.
// The distances are stored as a (possibly negative) offset that has to be added (+) to to the objectiveResults.
std::vector<ValueType> offsetsToUnderApproximation;
std::vector<ValueType> offsetsToOverApproximation;
// The scheduler choices that optimize the weighted rewards of undounded objectives.
std::vector<uint_fast64_t> optimalChoices;
struct EcQuotient {
storm::storage::SparseMatrix<ValueType> matrix;
std::vector<uint_fast64_t> ecqToOriginalChoiceMapping;
std::vector<uint_fast64_t> originalToEcqStateMapping;
storm::storage::BitVector origReward0Choices;
std::vector<ValueType> auxStateValues;
std::vector<ValueType> auxChoiceValues;
};
boost::optional<EcQuotient> ecQuotient;
};
}
}
}