You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 

188 lines
7.8 KiB

/*
* GmmxxDtmcPrctlModelChecker.h
*
* Created on: 06.12.2012
* Author: Christian Dehnert
*/
#ifndef GMMXXDTMCPRCTLMODELCHECKER_H_
#define GMMXXDTMCPRCTLMODELCHECKER_H_
#include "src/utility/vector.h"
#include "src/models/Dtmc.h"
#include "src/modelChecker/DtmcPrctlModelChecker.h"
#include "src/solver/GraphAnalyzer.h"
#include "gmm/gmm_matrix.h"
#include "gmm/gmm_iter_solvers.h"
#include "log4cplus/logger.h"
#include "log4cplus/loggingmacros.h"
extern log4cplus::Logger logger;
namespace mrmc {
namespace modelChecker {
/*
* A model checking engine that makes use of the gmm++ backend.
*/
template <class Type>
class GmmxxDtmcPrctlModelChecker : public DtmcPrctlModelChecker<Type> {
public:
explicit GmmxxDtmcPrctlModelChecker(mrmc::models::Dtmc<Type>& dtmc) : DtmcPrctlModelChecker<Type>(dtmc) { }
virtual ~GmmxxDtmcPrctlModelChecker() { }
virtual mrmc::storage::BitVector* checkProbabilisticOperator(const mrmc::formula::ProbabilisticOperator<Type>& formula) const {
//FIXME: Implementation needed
return NULL;
}
virtual mrmc::storage::BitVector* checkProbabilisticIntervalOperator(const mrmc::formula::ProbabilisticIntervalOperator<Type>& formula) const {
std::vector<Type>* probabilisticResult = this->checkPathFormula(formula.getPathFormula());
mrmc::storage::BitVector* result = new mrmc::storage::BitVector(this->getModel().getNumberOfStates());
Type lower = formula.getLowerBound();
Type upper = formula.getUpperBound();
for (uint_fast64_t i = 0; i < this->getModel().getNumberOfStates(); ++i) {
if ((*probabilisticResult)[i] >= lower && (*probabilisticResult)[i] <= upper) result->set(i, true);
}
delete probabilisticResult;
return result;
}
virtual std::vector<Type>* checkBoundedUntil(const mrmc::formula::BoundedUntil<Type>& formula) const {
// First, we need to compute the states that satisfy the sub-formulas of the until-formula.
mrmc::storage::BitVector* leftStates = this->checkStateFormula(formula.getLeft());
mrmc::storage::BitVector* rightStates = this->checkStateFormula(formula.getRight());
// Copy the matrix before we make any changes.
mrmc::storage::SquareSparseMatrix<Type> tmpMatrix(*this->getModel().getTransitionProbabilityMatrix());
// Make all rows absorbing that violate both sub-formulas or satisfy the second sub-formula.
tmpMatrix.makeRowsAbsorbing((~*leftStates & *rightStates) | *rightStates);
// Transform the transition probability matrix to the gmm++ format to use its arithmetic.
gmm::csr_matrix<double>* gmmxxMatrix = tmpMatrix.toGMMXXSparseMatrix();
// Create the vector with which to multiply.
std::vector<Type>* result = new std::vector<Type>(this->getModel().getNumberOfStates());
mrmc::utility::setVectorValues(result, *rightStates, static_cast<double>(1.0));
// Now perform matrix-vector multiplication as long as we meet the bound of the formula.
for (uint_fast64_t i = 0; i < formula.getBound(); ++i) {
gmm::mult(*gmmxxMatrix, *result, *result);
}
// Delete intermediate results.
delete leftStates;
delete rightStates;
return result;
}
virtual std::vector<Type>* checkNext(const mrmc::formula::Next<Type>& formula) const {
// First, we need to compute the states that satisfy the sub-formula of the next-formula.
mrmc::storage::BitVector* nextStates = this->checkStateFormula(formula.getChild());
// Transform the transition probability matrix to the gmm++ format to use its arithmetic.
gmm::csr_matrix<double>* gmmxxMatrix = this->getModel().getTransitionProbabilityMatrix()->toGMMXXSparseMatrix();
// Create the vector with which to multiply and initialize it correctly.
std::vector<Type> x(this->getModel().getNumberOfStates());
mrmc::utility::setVectorValues(&x, *nextStates, static_cast<double>(1.0));
// Delete not needed next states bit vector.
delete nextStates;
// Create resulting vector.
std::vector<Type>* result = new std::vector<Type>(this->getModel().getNumberOfStates());
// Perform the actual computation.
gmm::mult(*gmmxxMatrix, x, *result);
// Delete temporary matrix and return result.
delete gmmxxMatrix;
return result;
}
virtual std::vector<Type>* checkUntil(const mrmc::formula::Until<Type>& formula) const {
// First, we need to compute the states that satisfy the sub-formulas of the until-formula.
mrmc::storage::BitVector* leftStates = this->checkStateFormula(formula.getLeft());
mrmc::storage::BitVector* rightStates = this->checkStateFormula(formula.getRight());
// Then, we need to identify the states which have to be taken out of the matrix, i.e.
// all states that have probability 0 and 1 of satisfying the until-formula.
mrmc::storage::BitVector notExistsPhiUntilPsiStates(this->getModel().getNumberOfStates());
mrmc::storage::BitVector alwaysPhiUntilPsiStates(this->getModel().getNumberOfStates());
mrmc::solver::GraphAnalyzer::getPhiUntilPsiStates<double>(this->getModel(), *leftStates, *rightStates, &notExistsPhiUntilPsiStates, &alwaysPhiUntilPsiStates);
notExistsPhiUntilPsiStates.complement();
delete leftStates;
delete rightStates;
LOG4CPLUS_INFO(logger, "Found " << notExistsPhiUntilPsiStates.getNumberOfSetBits() << " 'no' states.");
LOG4CPLUS_INFO(logger, "Found " << alwaysPhiUntilPsiStates.getNumberOfSetBits() << " 'yes' states.");
mrmc::storage::BitVector maybeStates = ~(notExistsPhiUntilPsiStates | alwaysPhiUntilPsiStates);
LOG4CPLUS_INFO(logger, "Found " << maybeStates.getNumberOfSetBits() << " 'maybe' states.");
// Create resulting vector and set values accordingly.
std::vector<Type>* result = new std::vector<Type>(this->getModel().getNumberOfStates());
// Only try to solve system if there are states for which the probability is unknown.
if (maybeStates.getNumberOfSetBits() > 0) {
// Now we can eliminate the rows and columns from the original transition probability matrix.
mrmc::storage::SquareSparseMatrix<double>* submatrix = this->getModel().getTransitionProbabilityMatrix()->getSubmatrix(maybeStates);
// Converting the matrix to the form needed for the equation system. That is, we go from
// x = A*x + b to (I-A)x = b.
submatrix->convertToEquationSystem();
// Transform the submatrix to the gmm++ format to use its solvers.
gmm::csr_matrix<double>* gmmxxMatrix = submatrix->toGMMXXSparseMatrix();
// Initialize the x vector with 0.5 for each element. This is the initial guess for
// the iterative solvers. It should be safe as for all 'maybe' states we know that the
// probability is strictly larger than 0.
std::vector<Type> x(maybeStates.getNumberOfSetBits(), Type(0.5));
// Prepare the right-hand side of the equation system. For entry i this corresponds to
// the accumulated probability of going from state i to some 'yes' state.
std::vector<double> b(maybeStates.getNumberOfSetBits());
this->getModel().getTransitionProbabilityMatrix()->getConstrainedRowCountVector(maybeStates, alwaysPhiUntilPsiStates, &x);
// Set up the precondition of the iterative solver.
gmm::ilu_precond<gmm::csr_matrix<double>> P(*gmmxxMatrix);
// Prepare an iteration object that determines the accuracy, maximum number of iterations
// and the like.
gmm::iteration iter(0.000001);
// Now do the actual solving.
LOG4CPLUS_INFO(logger, "Starting iterative solver.");
gmm::bicgstab(*gmmxxMatrix, x, b, P, iter);
LOG4CPLUS_INFO(logger, "Iterative solver converged.");
// Set values of resulting vector according to result.
mrmc::utility::setVectorValues<Type>(result, maybeStates, x);
// Delete temporary matrix.
delete gmmxxMatrix;
}
mrmc::utility::setVectorValues<Type>(result, notExistsPhiUntilPsiStates, static_cast<double>(0));
mrmc::utility::setVectorValues<Type>(result, alwaysPhiUntilPsiStates, static_cast<double>(1.0));
return result;
}
};
} //namespace modelChecker
} //namespace mrmc
#endif /* GMMXXDTMCPRCTLMODELCHECKER_H_ */