@ -47,6 +47,24 @@ namespace storm {
return diff ;
}
template < typename PomdpModelType , typename BeliefValueType >
bool ApproximatePOMDPModelchecker < PomdpModelType , BeliefValueType > : : Result : : updateLowerBound ( ValueType const & value ) {
if ( value > lowerBound ) {
lowerBound = value ;
return true ;
}
return false ;
}
template < typename PomdpModelType , typename BeliefValueType >
bool ApproximatePOMDPModelchecker < PomdpModelType , BeliefValueType > : : Result : : updateUpperBound ( ValueType const & value ) {
if ( value < upperBound ) {
upperBound = value ;
return true ;
}
return false ;
}
template < typename PomdpModelType , typename BeliefValueType >
ApproximatePOMDPModelchecker < PomdpModelType , BeliefValueType > : : Statistics : : Statistics ( ) : overApproximationBuildAborted ( false ) , underApproximationBuildAborted ( false ) , aborted ( false ) {
// intentionally left empty;
@ -62,13 +80,15 @@ namespace storm {
STORM_LOG_ASSERT ( options . unfold | | options . discretize , " Invoked belief exploration but no task (unfold or discretize) given. " ) ;
// Reset all collected statistics
statistics = Statistics ( ) ;
statistics . totalTime . start ( ) ;
// Extract the relevant information from the formula
auto formulaInfo = storm : : pomdp : : analysis : : getFormulaInformation ( pomdp , formula ) ;
// Compute some initial bounds on the values for each state of the pomdp
auto initialPomdpValueBounds = TrivialPomdpValueBoundsModelChecker < storm : : models : : sparse : : Pomdp < ValueType > > ( pomdp ) . getValueBounds ( formula , formulaInfo ) ;
Result result ( initialPomdpValueBounds . lower [ pomdp . getInitialStates ( ) . getNextSetIndex ( 0 ) ] , initialPomdpValueBounds . upper [ pomdp . getInitialStates ( ) . getNextSetIndex ( 0 ) ] ) ;
STORM_PRINT_AND_LOG ( " Initial value bounds are [ " < < result . lowerBound < < " , " < < result . upperBound < < " ] " < < std : : endl ) ;
boost : : optional < std : : string > rewardModelName ;
if ( formulaInfo . isNonNestedReachabilityProbability ( ) | | formulaInfo . isNonNestedExpectedRewardFormula ( ) ) {
// FIXME: Instead of giving up, introduce a new observation for target states and make sink states absorbing.
@ -103,6 +123,7 @@ namespace storm {
if ( storm : : utility : : resources : : isTerminate ( ) ) {
statistics . aborted = true ;
}
statistics . totalTime . stop ( ) ;
return result ;
}
@ -117,6 +138,8 @@ namespace storm {
stream < < " # Computation aborted early " < < std : : endl ;
}
stream < < " # Total check time: " < < statistics . totalTime < < std : : endl ;
// Refinement information:
if ( statistics . refinementSteps ) {
stream < < " # Number of refinement steps: " < < statistics . refinementSteps . get ( ) < < std : : endl ;
@ -208,9 +231,6 @@ namespace storm {
template < typename PomdpModelType , typename BeliefValueType >
void ApproximatePOMDPModelchecker < PomdpModelType , BeliefValueType > : : refineReachability ( std : : set < uint32_t > const & targetObservations , bool min , boost : : optional < std : : string > rewardModelName , std : : vector < ValueType > const & lowerPomdpValueBounds , std : : vector < ValueType > const & upperPomdpValueBounds , Result & result ) {
ValueType & overApproxValue = min ? result . lowerBound : result . upperBound ;
ValueType & underApproxValue = min ? result . upperBound : result . lowerBound ;
// Set up exploration data
std : : vector < uint64_t > observationResolutionVector ;
std : : shared_ptr < BeliefManagerType > overApproxBeliefManager ;
@ -231,7 +251,9 @@ namespace storm {
if ( ! overApproximation - > hasComputedValues ( ) ) {
return ;
}
overApproxValue = overApproximation - > getComputedValueAtInitialState ( ) ;
ValueType const & newValue = overApproximation - > getComputedValueAtInitialState ( ) ;
bool betterBound = min ? result . updateLowerBound ( newValue ) : result . updateUpperBound ( newValue ) ;
STORM_PRINT_AND_LOG ( " Over-approx result for refinement step #0 is ' " < < newValue < < " ' which " < < std : : string ( betterBound ? " improves " : " does not improve " ) < < " the old value. Current runtime is " < < statistics . totalTime < < " seconds. " < < std : : endl ) ;
}
std : : shared_ptr < BeliefManagerType > underApproxBeliefManager ;
@ -254,7 +276,9 @@ namespace storm {
if ( ! underApproximation - > hasComputedValues ( ) ) {
return ;
}
underApproxValue = underApproximation - > getComputedValueAtInitialState ( ) ;
ValueType const & newValue = underApproximation - > getComputedValueAtInitialState ( ) ;
bool betterBound = min ? result . updateUpperBound ( newValue ) : result . updateLowerBound ( newValue ) ;
STORM_PRINT_AND_LOG ( " Under-approx result for refinement step #0 is ' " < < newValue < < " ' which " < < std : : string ( betterBound ? " improves " : " does not improve " ) < < " the old value. Current runtime is " < < statistics . totalTime < < " seconds. " < < std : : endl ) ;
}
// Start refinement
@ -281,7 +305,9 @@ namespace storm {
overApproxHeuristicPar . optimalChoiceValueEpsilon * = options . optimalChoiceValueThresholdFactor ;
buildOverApproximation ( targetObservations , min , rewardModelName . is_initialized ( ) , true , overApproxHeuristicPar , observationResolutionVector , overApproxBeliefManager , overApproximation ) ;
if ( overApproximation - > hasComputedValues ( ) ) {
overApproxValue = overApproximation - > getComputedValueAtInitialState ( ) ;
ValueType const & newValue = overApproximation - > getComputedValueAtInitialState ( ) ;
bool betterBound = min ? result . updateLowerBound ( newValue ) : result . updateUpperBound ( newValue ) ;
STORM_PRINT_AND_LOG ( " Over-approx result for refinement step # " < < statistics . refinementSteps . get ( ) < < " is ' " < < newValue < < " ' which " < < std : : string ( betterBound ? " improves " : " does not improve " ) < < " the old value. Current runtime is " < < statistics . totalTime < < " seconds. " < < std : : endl ) ;
} else {
break ;
}
@ -294,7 +320,9 @@ namespace storm {
overApproxHeuristicPar . optimalChoiceValueEpsilon * = options . optimalChoiceValueThresholdFactor ;
buildUnderApproximation ( targetObservations , min , rewardModelName . is_initialized ( ) , true , underApproxHeuristicPar , underApproxBeliefManager , underApproximation ) ;
if ( underApproximation - > hasComputedValues ( ) ) {
underApproxValue = underApproximation - > getComputedValueAtInitialState ( ) ;
ValueType const & newValue = underApproximation - > getComputedValueAtInitialState ( ) ;
bool betterBound = min ? result . updateUpperBound ( newValue ) : result . updateLowerBound ( newValue ) ;
STORM_PRINT_AND_LOG ( " Under-approx result for refinement step # " < < statistics . refinementSteps . get ( ) < < " is ' " < < newValue < < " ' which " < < std : : string ( betterBound ? " improves " : " does not improve " ) < < " the old value. Current runtime is " < < statistics . totalTime < < " seconds. " < < std : : endl ) ;
} else {
break ;
}