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Fixed cases where a solver guarantee was not established although it was needed by the termination condition

tempestpy_adaptions
TimQu 7 years ago
parent
117d1b5c99
commit
d85a845b7d
4 changed files with 79 additions and 53 deletions
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  1. 94
      src/storm/solver/IterativeMinMaxLinearEquationSolver.cpp
  2. 2
      src/storm/solver/IterativeMinMaxLinearEquationSolver.h
  3. 20
      src/storm/solver/TerminationCondition.cpp
  4. 16
      src/storm/solver/TerminationCondition.h

94
src/storm/solver/IterativeMinMaxLinearEquationSolver.cpp
View File

@ -144,6 +144,37 @@ namespace storm {
return result;
}
template<typename ValueType>
bool IterativeMinMaxLinearEquationSolver<ValueType>::solveInducedEquationSystem(std::unique_ptr<LinearEquationSolver<ValueType>>& linearEquationSolver, std::vector<uint64_t> const& scheduler, std::vector<ValueType>& x, std::vector<ValueType>& subB, std::vector<ValueType> const& originalB) const {
assert(subB.size() == x.size());
// Resolve the nondeterminism according to the given scheduler.
bool convertToEquationSystem = this->linearEquationSolverFactory->getEquationProblemFormat() == LinearEquationSolverProblemFormat::EquationSystem;
storm::storage::SparseMatrix<ValueType> submatrix = this->A->selectRowsFromRowGroups(scheduler, convertToEquationSystem);
if (convertToEquationSystem) {
submatrix.convertToEquationSystem();
}
storm::utility::vector::selectVectorValues<ValueType>(subB, scheduler, this->A->getRowGroupIndices(), originalB);
// Check whether the linear equation solver is already initialized
if (!linearEquationSolver) {
// Initialize the equation solver
linearEquationSolver = this->linearEquationSolverFactory->create(std::move(submatrix));
if (this->lowerBound) { // TODO
linearEquationSolver->setLowerBound(this->lowerBound.get());
}
if (this->upperBound) {
linearEquationSolver->setUpperBound(this->upperBound.get());
}
linearEquationSolver->setCachingEnabled(true);
} else {
// If the equation solver is already initialized, it suffices to update the matrix
linearEquationSolver->setMatrix(std::move(submatrix));
}
// Solve the equation system for the 'DTMC' and return true upon success
return linearEquationSolver->solveEquations(x, subB);
}
template<typename ValueType>
bool IterativeMinMaxLinearEquationSolver<ValueType>::solveEquationsPolicyIteration(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const {
@ -156,30 +187,15 @@ namespace storm {
}
std::vector<ValueType>& subB = *auxiliaryRowGroupVector;
// Resolve the nondeterminism according to the current scheduler.
bool convertToEquationSystem = this->linearEquationSolverFactory->getEquationProblemFormat() == LinearEquationSolverProblemFormat::EquationSystem;
storm::storage::SparseMatrix<ValueType> submatrix = this->A->selectRowsFromRowGroups(scheduler, convertToEquationSystem);
if (convertToEquationSystem) {
submatrix.convertToEquationSystem();
}
storm::utility::vector::selectVectorValues<ValueType>(subB, scheduler, this->A->getRowGroupIndices(), b);
// Create a solver that we will use throughout the procedure. We will modify the matrix in each iteration.
auto solver = this->linearEquationSolverFactory->create(std::move(submatrix));
if (this->lowerBound) {
solver->setLowerBound(this->lowerBound.get());
}
if (this->upperBound) {
solver->setUpperBound(this->upperBound.get());
}
solver->setCachingEnabled(true);
// The solver that we will use throughout the procedure.
std::unique_ptr<storm::solver::LinearEquationSolver<ValueType>> solver;
SolverStatus status = SolverStatus::InProgress;
uint64_t iterations = 0;
this->startMeasureProgress();
do {
// Solve the equation system for the 'DTMC'.
solver->solveEquations(x, subB);
solveInducedEquationSystem(solver, scheduler, x, subB, b);
// Go through the multiplication result and see whether we can improve any of the choices.
bool schedulerImproved = false;
@ -212,14 +228,6 @@ namespace storm {
// If the scheduler did not improve, we are done.
if (!schedulerImproved) {
status = SolverStatus::Converged;
} else {
// Update the scheduler and the solver.
submatrix = this->A->selectRowsFromRowGroups(scheduler, true);
if (convertToEquationSystem) {
submatrix.convertToEquationSystem();
}
storm::utility::vector::selectVectorValues<ValueType>(subB, scheduler, this->A->getRowGroupIndices(), b);
solver->setMatrix(std::move(submatrix));
}
// Update environment variables.
@ -376,37 +384,25 @@ namespace storm {
SolverGuarantee guarantee = SolverGuarantee::None;
if (this->hasInitialScheduler()) {
// Resolve the nondeterminism according to the initial scheduler.
bool convertToEquationSystem = this->linearEquationSolverFactory->getEquationProblemFormat() == LinearEquationSolverProblemFormat::EquationSystem;
storm::storage::SparseMatrix<ValueType> submatrix = this->A->selectRowsFromRowGroups(this->getInitialScheduler(), convertToEquationSystem);
if (convertToEquationSystem) {
submatrix.convertToEquationSystem();
}
storm::utility::vector::selectVectorValues<ValueType>(*auxiliaryRowGroupVector, this->getInitialScheduler(), this->A->getRowGroupIndices(), b);
// Solve the resulting equation system.
auto submatrixSolver = this->linearEquationSolverFactory->create(std::move(submatrix));
submatrixSolver->setCachingEnabled(true);
if (this->lowerBound) {
submatrixSolver->setLowerBound(this->lowerBound.get());
}
if (this->upperBound) {
submatrixSolver->setUpperBound(this->upperBound.get());
}
submatrixSolver->solveEquations(x, *auxiliaryRowGroupVector);
// Solve the equation system induced by the initial scheduler.
std::unique_ptr<storm::solver::LinearEquationSolver<ValueType>> linEqSolver;
solveInducedEquationSystem(linEqSolver, this->getInitialScheduler(), x, *auxiliaryRowGroupVector, b);
// If we were given an initial scheduler and are maximizing (minimizing), our current solution becomes
// always less-or-equal (greater-or-equal) than the actual solution.
if (dir == storm::OptimizationDirection::Maximize) {
guarantee = maximize(dir) ? SolverGuarantee::LessOrEqual : SolverGuarantee::GreaterOrEqual;
} else if (!this->hasUniqueSolution()) {
if (maximize(dir)) {
this->createLowerBoundsVector(x);
guarantee = SolverGuarantee::LessOrEqual;
} else {
this->createUpperBoundsVector(x);
guarantee = SolverGuarantee::GreaterOrEqual;
}
} else if (!this->hasUniqueSolution()) {
if (dir == storm::OptimizationDirection::Maximize) {
} else if (this->hasCustomTerminationCondition()) {
if (this->getTerminationCondition().requiresGuarantee(SolverGuarantee::LessOrEqual)) {
this->createLowerBoundsVector(x);
guarantee = SolverGuarantee::LessOrEqual;
} else {
} else if (this->getTerminationCondition().requiresGuarantee(SolverGuarantee::GreaterOrEqual)) {
this->createUpperBoundsVector(x);
guarantee = SolverGuarantee::GreaterOrEqual;
}

2
src/storm/solver/IterativeMinMaxLinearEquationSolver.h
View File

@ -67,12 +67,12 @@ namespace storm {
virtual MinMaxLinearEquationSolverRequirements getRequirements(boost::optional<storm::solver::OptimizationDirection> const& direction = boost::none) const override;
private:
bool solveInducedEquationSystem(std::unique_ptr<LinearEquationSolver<ValueType>>& linearEquationSolver, std::vector<uint64_t> const& scheduler, std::vector<ValueType>& x, std::vector<ValueType>& subB, std::vector<ValueType> const& originalB) const;
bool solveEquationsPolicyIteration(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
bool valueImproved(OptimizationDirection dir, ValueType const& value1, ValueType const& value2) const;
bool solveEquationsValueIteration(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
bool solveEquationsSoundValueIteration(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
bool solveEquationsAcyclic(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
bool solveEquationsRationalSearch(OptimizationDirection dir, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
template<typename RationalType, typename ImpreciseType>

20
src/storm/solver/TerminationCondition.cpp
View File

@ -13,6 +13,11 @@ namespace storm {
return false;
}
template<typename ValueType>
bool NoTerminationCondition<ValueType>::requiresGuarantee(SolverGuarantee const&) const {
return false;
}
template<typename ValueType>
TerminateIfFilteredSumExceedsThreshold<ValueType>::TerminateIfFilteredSumExceedsThreshold(storm::storage::BitVector const& filter, ValueType const& threshold, bool strict) : threshold(threshold), filter(filter), strict(strict) {
// Intentionally left empty.
@ -29,6 +34,11 @@ namespace storm {
return strict ? currentThreshold > this->threshold : currentThreshold >= this->threshold;
}
template<typename ValueType>
bool TerminateIfFilteredSumExceedsThreshold<ValueType>::requiresGuarantee(SolverGuarantee const& guarantee) const {
return guarantee == SolverGuarantee::LessOrEqual;
}
template<typename ValueType>
TerminateIfFilteredExtremumExceedsThreshold<ValueType>::TerminateIfFilteredExtremumExceedsThreshold(storm::storage::BitVector const& filter, bool strict, ValueType const& threshold, bool useMinimum) : TerminateIfFilteredSumExceedsThreshold<ValueType>(filter, threshold, strict), useMinimum(useMinimum) {
// Intentionally left empty.
@ -45,6 +55,11 @@ namespace storm {
return this->strict ? currentValue > this->threshold : currentValue >= this->threshold;
}
template<typename ValueType>
bool TerminateIfFilteredExtremumExceedsThreshold<ValueType>::requiresGuarantee(SolverGuarantee const& guarantee) const {
return guarantee == SolverGuarantee::LessOrEqual;
}
template<typename ValueType>
TerminateIfFilteredExtremumBelowThreshold<ValueType>::TerminateIfFilteredExtremumBelowThreshold(storm::storage::BitVector const& filter, bool strict, ValueType const& threshold, bool useMinimum) : TerminateIfFilteredSumExceedsThreshold<ValueType>(filter, threshold, strict), useMinimum(useMinimum) {
// Intentionally left empty.
@ -61,6 +76,11 @@ namespace storm {
return this->strict ? currentValue < this->threshold : currentValue <= this->threshold;
}
template<typename ValueType>
bool TerminateIfFilteredExtremumBelowThreshold<ValueType>::requiresGuarantee(SolverGuarantee const& guarantee) const {
return guarantee == SolverGuarantee::GreaterOrEqual;
}
template class TerminateIfFilteredSumExceedsThreshold<double>;
template class TerminateIfFilteredExtremumExceedsThreshold<double>;
template class TerminateIfFilteredExtremumBelowThreshold<double>;

16
src/storm/solver/TerminationCondition.h
View File

@ -14,12 +14,19 @@ namespace storm {
* Retrieves whether the guarantee provided by the solver for the current result is sufficient to terminate.
*/
virtual bool terminateNow(std::vector<ValueType> const& currentValues, SolverGuarantee const& guarantee = SolverGuarantee::None) const = 0;
/*!
* Retrieves whether the termination criterion requires the given guarantee in order to decide termination.
* @return
*/
virtual bool requiresGuarantee(SolverGuarantee const& guarantee) const = 0;
};
template<typename ValueType>
class NoTerminationCondition : public TerminationCondition<ValueType> {
public:
virtual bool terminateNow(std::vector<ValueType> const& currentValues, SolverGuarantee const& guarantee = SolverGuarantee::None) const override;
virtual bool requiresGuarantee(SolverGuarantee const& guarantee) const override;
};
template<typename ValueType>
@ -27,7 +34,8 @@ namespace storm {
public:
TerminateIfFilteredSumExceedsThreshold(storm::storage::BitVector const& filter, ValueType const& threshold, bool strict);
bool terminateNow(std::vector<ValueType> const& currentValues, SolverGuarantee const& guarantee = SolverGuarantee::None) const;
bool terminateNow(std::vector<ValueType> const& currentValues, SolverGuarantee const& guarantee = SolverGuarantee::None) const override;
virtual bool requiresGuarantee(SolverGuarantee const& guarantee) const override;
protected:
ValueType threshold;
@ -40,7 +48,8 @@ namespace storm {
public:
TerminateIfFilteredExtremumExceedsThreshold(storm::storage::BitVector const& filter, bool strict, ValueType const& threshold, bool useMinimum);
bool terminateNow(std::vector<ValueType> const& currentValue, SolverGuarantee const& guarantee = SolverGuarantee::None) const;
bool terminateNow(std::vector<ValueType> const& currentValue, SolverGuarantee const& guarantee = SolverGuarantee::None) const override;
virtual bool requiresGuarantee(SolverGuarantee const& guarantee) const override;
protected:
bool useMinimum;
@ -51,7 +60,8 @@ namespace storm {
public:
TerminateIfFilteredExtremumBelowThreshold(storm::storage::BitVector const& filter, bool strict, ValueType const& threshold, bool useMinimum);
bool terminateNow(std::vector<ValueType> const& currentValue, SolverGuarantee const& guarantee = SolverGuarantee::None) const;
bool terminateNow(std::vector<ValueType> const& currentValue, SolverGuarantee const& guarantee = SolverGuarantee::None) const override;
virtual bool requiresGuarantee(SolverGuarantee const& guarantee) const override;
protected:
bool useMinimum;

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