gtsam/gtsam_unstable/discrete/Domain.h

107 lines
3.1 KiB
C++

/*
* Domain.h
* @brief Domain restriction constraint
* @date Feb 13, 2012
* @author Frank Dellaert
*/
#pragma once
#include <gtsam/discrete/DiscreteKey.h>
#include <gtsam_unstable/discrete/Constraint.h>
namespace gtsam {
/**
* The Domain class represents a constraint that restricts the possible values a
* particular variable, with given key, can take on.
*/
class GTSAM_UNSTABLE_EXPORT Domain : public Constraint {
size_t cardinality_; /// Cardinality
std::set<size_t> values_; /// allowed values
DiscreteKey discreteKey() const {
return DiscreteKey(keys_[0], cardinality_);
}
public:
typedef boost::shared_ptr<Domain> shared_ptr;
// Constructor on Discrete Key initializes an "all-allowed" domain
Domain(const DiscreteKey& dkey)
: Constraint(dkey.first), cardinality_(dkey.second) {
for (size_t v = 0; v < cardinality_; v++) values_.insert(v);
}
// Constructor on Discrete Key with single allowed value
// Consider SingleValue constraint
Domain(const DiscreteKey& dkey, size_t v)
: Constraint(dkey.first), cardinality_(dkey.second) {
values_.insert(v);
}
/// Insert a value, non const :-(
void insert(size_t value) { values_.insert(value); }
/// Erase a value, non const :-(
void erase(size_t value) { values_.erase(value); }
size_t nrValues() const { return values_.size(); }
bool isSingleton() const { return nrValues() == 1; }
size_t firstValue() const { return *values_.begin(); }
// print
void print(const std::string& s = "", const KeyFormatter& formatter =
DefaultKeyFormatter) const override;
/// equals
bool equals(const DiscreteFactor& other, double tol) const override {
if (!dynamic_cast<const Domain*>(&other))
return false;
else {
const Domain& f(static_cast<const Domain&>(other));
return (cardinality_ == f.cardinality_) && (values_ == f.values_);
}
}
bool contains(size_t value) const { return values_.count(value) > 0; }
/// Calculate value
double operator()(const Values& values) const override;
/// Convert into a decisiontree
DecisionTreeFactor toDecisionTreeFactor() const override;
/// Multiply into a decisiontree
DecisionTreeFactor operator*(const DecisionTreeFactor& f) const override;
/*
* Ensure Arc-consistency
* @param j domain to be checked
* @param domains all other domains
*/
bool ensureArcConsistency(size_t j,
std::vector<Domain>* domains) const override;
/**
* Check for a value in domain that does not occur in any other connected
* domain. If found, return a a new singleton domain...
* Called in AllDiff::ensureArcConsistency
* @param keys connected domains through alldiff
* @param keys other domains
*/
boost::optional<Domain> checkAllDiff(
const KeyVector keys, const std::vector<Domain>& domains) const;
/// Partially apply known values
Constraint::shared_ptr partiallyApply(const Values& values) const override;
/// Partially apply known values, domain version
Constraint::shared_ptr partiallyApply(
const std::vector<Domain>& domains) const override;
};
} // namespace gtsam