diff --git a/src/storm/environment/solver/OviSolverEnvironment.cpp b/src/storm/environment/solver/OviSolverEnvironment.cpp
index a5007aa78..fe6a21a12 100644
--- a/src/storm/environment/solver/OviSolverEnvironment.cpp
+++ b/src/storm/environment/solver/OviSolverEnvironment.cpp
@@ -14,6 +14,7 @@ namespace storm {
relevantValuesForPrecisionUpdate = oviSettings.useRelevantValuesForPrecisionUpdate();
upperBoundGuessingFactor = storm::utility::convertNumber<storm::RationalNumber>(oviSettings.getUpperBoundGuessingFactor());
upperBoundOnlyIterations = oviSettings.getUpperBoundOnlyIterations();
+ noTerminationGuaranteeMinimumMethod = oviSettings.useNoTerminationGuaranteeMinimumMethod();
}
OviSolverEnvironment::~OviSolverEnvironment() {
@@ -33,11 +34,15 @@ namespace storm {
}
storm::RationalNumber OviSolverEnvironment::getUpperBoundGuessingFactor() const {
- return maxVerificationIterationFactor;
+ return upperBoundGuessingFactor;
}
uint64_t OviSolverEnvironment::getUpperBoundOnlyIterations() const {
return upperBoundOnlyIterations;
}
+
+ bool OviSolverEnvironment::useNoTerminationGuaranteeMinimumMethod() const {
+ return noTerminationGuaranteeMinimumMethod;
+ }
}
diff --git a/src/storm/environment/solver/OviSolverEnvironment.h b/src/storm/environment/solver/OviSolverEnvironment.h
index 74a99e518..0875bad9a 100644
--- a/src/storm/environment/solver/OviSolverEnvironment.h
+++ b/src/storm/environment/solver/OviSolverEnvironment.h
@@ -17,6 +17,7 @@ namespace storm {
bool useRelevantValuesForPrecisionUpdate() const;
storm::RationalNumber getUpperBoundGuessingFactor() const;
uint64_t getUpperBoundOnlyIterations() const;
+ bool useNoTerminationGuaranteeMinimumMethod() const;
private:
storm::RationalNumber precisionUpdateFactor;
@@ -24,6 +25,7 @@ namespace storm {
bool relevantValuesForPrecisionUpdate;
storm::RationalNumber upperBoundGuessingFactor;
uint64_t upperBoundOnlyIterations;
+ bool noTerminationGuaranteeMinimumMethod;
};
}
diff --git a/src/storm/settings/modules/OviSolverSettings.cpp b/src/storm/settings/modules/OviSolverSettings.cpp
index c617db06f..46cc82f36 100644
--- a/src/storm/settings/modules/OviSolverSettings.cpp
+++ b/src/storm/settings/modules/OviSolverSettings.cpp
@@ -17,7 +17,8 @@ namespace storm {
const std::string OviSolverSettings::useRelevantValuesForPrecisionUpdateOptionName = "use-relevant-values";
const std::string OviSolverSettings::upperBoundGuessingFactorOptionName = "upper-bound-factor";
const std::string OviSolverSettings::upperBoundOnlyIterationsOptionName = "check-upper-only-iter";
-
+ const std::string OviSolverSettings::useNoTerminationGuaranteeMinimumMethodOptionName = "no-termination-guarantee";
+
OviSolverSettings::OviSolverSettings() : ModuleSettings(moduleName) {
this->addOption(storm::settings::OptionBuilder(moduleName, precisionUpdateFactorOptionName, false, "Sets with which factor the precision of the inner value iteration is updated.").setIsAdvanced().addArgument(storm::settings::ArgumentBuilder::createDoubleArgument("factor", "The factor.").setDefaultValueDouble(0.4).addValidatorDouble(ArgumentValidatorFactory::createDoubleRangeValidatorExcluding(0.0, 1.0)).build()).build());
@@ -29,6 +30,8 @@ namespace storm {
this->addOption(storm::settings::OptionBuilder(moduleName, upperBoundGuessingFactorOptionName, false, "Sets with which factor the precision is multiplied to guess the upper bound.").setIsAdvanced().addArgument(storm::settings::ArgumentBuilder::createDoubleArgument("factor", "The factor.").setDefaultValueDouble(1.0).addValidatorDouble(ArgumentValidatorFactory::createDoubleGreaterValidator(0.0)).build()).build());
this->addOption(storm::settings::OptionBuilder(moduleName, upperBoundOnlyIterationsOptionName, false, "Sets the max. iterations OVI will only iterate over the upper bound.").setIsAdvanced().addArgument(storm::settings::ArgumentBuilder::createIntegerArgument("iter", "The iterations.").setDefaultValueInteger(20000).addValidatorInteger(ArgumentValidatorFactory::createIntegerGreaterValidator(0)).build()).build());
+
+ this->addOption(storm::settings::OptionBuilder(moduleName, useNoTerminationGuaranteeMinimumMethodOptionName, false, "Sets whether to perform element-wise minimum of iterated and old upper bound. If this option is set, that will be skipped, slightly increasing performance but giving no termination guarantee.").setShortName("ntg").setIsAdvanced().build());
}
double OviSolverSettings::getPrecisionUpdateFactor() const {
@@ -50,6 +53,10 @@ namespace storm {
uint64_t OviSolverSettings::getUpperBoundOnlyIterations() const {
return this->getOption(upperBoundOnlyIterationsOptionName).getArgumentByName("iter").getValueAsInteger();
}
+
+ bool OviSolverSettings::useNoTerminationGuaranteeMinimumMethod() const {
+ return this->getOption(useNoTerminationGuaranteeMinimumMethodOptionName).getHasOptionBeenSet();
+ }
}
}
diff --git a/src/storm/settings/modules/OviSolverSettings.h b/src/storm/settings/modules/OviSolverSettings.h
index 21884169d..70c1c4f0f 100644
--- a/src/storm/settings/modules/OviSolverSettings.h
+++ b/src/storm/settings/modules/OviSolverSettings.h
@@ -24,7 +24,8 @@ namespace storm {
double getUpperBoundGuessingFactor() const;
uint64_t getUpperBoundOnlyIterations() const;
-
+
+ bool useNoTerminationGuaranteeMinimumMethod() const;
// The name of the module.
static const std::string moduleName;
@@ -35,6 +36,7 @@ namespace storm {
static const std::string useRelevantValuesForPrecisionUpdateOptionName;
static const std::string upperBoundGuessingFactorOptionName;
static const std::string upperBoundOnlyIterationsOptionName;
+ static const std::string useNoTerminationGuaranteeMinimumMethodOptionName;
};
}
diff --git a/src/storm/solver/helper/OptimisticValueIterationHelper.h b/src/storm/solver/helper/OptimisticValueIterationHelper.h
index 2869540d6..22cad53fc 100644
--- a/src/storm/solver/helper/OptimisticValueIterationHelper.h
+++ b/src/storm/solver/helper/OptimisticValueIterationHelper.h
@@ -82,7 +82,7 @@ namespace storm {
void guessUpperBoundAbsolute(std::vector<ValueType> const& x, std::vector<ValueType> &target, ValueType const& precision) {
storm::utility::vector::applyPointwise<ValueType, ValueType>(x, target, [&precision] (ValueType const& argument) -> ValueType { return argument + precision; });
}
-
+
}
@@ -122,6 +122,8 @@ namespace storm {
ValueType two = storm::utility::convertNumber<ValueType>(2.0);
// Relative errors
bool relative = env.solver().minMax().getRelativeTerminationCriterion();
+ // Use no termination guaranteed upper bound iteration method
+ bool noTerminationGuarantee = env.solver().ovi().useNoTerminationGuaranteeMinimumMethod();
// Goal precision
ValueType precision = storm::utility::convertNumber<ValueType>(env.solver().minMax().getPrecision());
// Desired max difference between upperX and lowerX
@@ -137,54 +139,86 @@ namespace storm {
SolverStatus status = SolverStatus::InProgress;
while (status == SolverStatus::InProgress && overallIterations < maxOverallIterations) {
-
+
// Perform value iteration until convergence
++valueIterationInvocations;
auto result = valueIterationCallback(lowerX, auxVector, iterationPrecision, relative, overallIterations, maxOverallIterations);
lastValueIterationIterations = result.iterations;
overallIterations += result.iterations;
-
+
if (result.status != SolverStatus::Converged) {
status = result.status;
} else {
bool intervalIterationNeeded = false;
currentVerificationIterations = 0;
-
+
if (relative) {
oviinternal::guessUpperBoundRelative(*lowerX, *upperX, relativeBoundGuessingScaler);
} else {
oviinternal::guessUpperBoundAbsolute(*lowerX, *upperX, precision);
}
-
+
bool cancelGuess = false;
while (status == SolverStatus::InProgress && overallIterations < maxOverallIterations) {
++overallIterations;
++currentVerificationIterations;
// Perform value iteration stepwise for lower bound and guessed upper bound
-
+
// Upper bound iteration
singleIterationCallback(upperX, auxVector, overallIterations);
- // At this point, auxVector contains the old values for the upper bound whereas upperX contains the new ones.
-
+ // At this point,h auxVector contains the old values for the upper bound whereas upperX contains the new ones.
+
// Compare the new upper bound candidate with the old one
bool newUpperBoundAlwaysHigherEqual = true;
bool newUpperBoundAlwaysLowerEqual = true;
- for (uint64_t i = 0; i < upperX->size(); ++i) {
- if ((*auxVector)[i] > (*upperX)[i]) {
- newUpperBoundAlwaysHigherEqual = false;
- } else if ((*auxVector)[i] != (*upperX)[i]) {
- newUpperBoundAlwaysLowerEqual = false;
+ if(noTerminationGuarantee) {
+ bool cancelOuterScan = false;
+ for (uint64_t i = 0; i < upperX->size() &! cancelOuterScan; ++i) {
+ if ((*upperX)[i] < (*auxVector)[i]) {
+ newUpperBoundAlwaysHigherEqual = false;
+ ++i;
+ while (i < upperX->size()) {
+ if ((*upperX)[i] > (*auxVector)[i]) {
+ newUpperBoundAlwaysLowerEqual = false;
+ cancelOuterScan = true;
+ break;
+ }
+ ++i;
+ }
+ } else if ((*upperX)[i] != (*auxVector)[i]) {
+ newUpperBoundAlwaysLowerEqual = false;
+ ++i;
+ while (i < upperX->size()) {
+ if ((*upperX)[i] < (*auxVector)[i]) {
+ newUpperBoundAlwaysHigherEqual = false;
+ cancelOuterScan = true;
+ break;
+ }
+ ++i;
+ }
+ }
+ }
+ }
+ else {
+ for (uint64_t i = 0; i < upperX->size(); ++i) {
+ if ((*upperX)[i] < (*auxVector)[i]) {
+ newUpperBoundAlwaysHigherEqual = false;
+ } else if ((*upperX)[i] != (*auxVector)[i]) {
+ newUpperBoundAlwaysLowerEqual = false;
+ std::swap((*upperX)[i], (*auxVector)[i]);
+ }
}
}
- if (newUpperBoundAlwaysHigherEqual & !newUpperBoundAlwaysLowerEqual) {
- // All values moved up or stayed the same (but are not the same)
+
+ if (newUpperBoundAlwaysHigherEqual &! newUpperBoundAlwaysLowerEqual) {
+ // All values moved up or stayed the same
// That means the guess for an upper bound is actually a lower bound
iterationPrecision = oviinternal::updateIterationPrecision(env, *auxVector, *upperX, relative, relevantValues);
// We assume to have a single fixed point. We can thus safely set the new lower bound, to the wrongly guessed upper bound
// Set lowerX to the upper bound candidate
std::swap(lowerX, upperX);
break;
- } else if (newUpperBoundAlwaysLowerEqual) {
+ } else if (newUpperBoundAlwaysLowerEqual &! newUpperBoundAlwaysHigherEqual) {
// All values moved down or stayed the same and we have a maximum difference of twice the requested precision
// We can safely use twice the requested precision, as we calculate the center of both vectors
bool reachedPrecision;
@@ -202,19 +236,19 @@ namespace storm {
}
}
// At this point, the old upper bounds (auxVector) are not needed anymore.
-
+
// Check whether we tried this guess for too long
ValueType scaledIterationCount = storm::utility::convertNumber<ValueType>(currentVerificationIterations) * storm::utility::convertNumber<ValueType>(env.solver().ovi().getMaxVerificationIterationFactor());
if (!intervalIterationNeeded && scaledIterationCount >= storm::utility::convertNumber<ValueType>(lastValueIterationIterations)) {
cancelGuess = true;
// In this case we will make one more iteration on the lower bound (mainly to obtain a new iterationPrecision)
}
-
+
// Lower bound iteration (only if needed)
if (cancelGuess || intervalIterationNeeded || currentVerificationIterations > upperBoundOnlyIterations) {
singleIterationCallback(lowerX, auxVector, overallIterations);
// At this point, auxVector contains the old values for the lower bound whereas lowerX contains the new ones.
-
+
// Check whether the upper and lower bounds have crossed, i.e., the upper bound is smaller than the lower bound.
bool valuesCrossed = false;
for (uint64_t i = 0; i < lowerX->size(); ++i) {
@@ -223,7 +257,7 @@ namespace storm {
break;
}
}
-
+
if (cancelGuess || valuesCrossed) {
// A new guess is needed.
iterationPrecision = oviinternal::updateIterationPrecision(env, *auxVector, *lowerX, relative, relevantValues);