Domain.h

/*
 * Domain.h
 * @brief Domain restriction constraint
 * @date Feb 13, 2012
 * @author Frank Dellaert
 */
 
#pragma once
 
#include <gtsam/discrete/Constraint.h>
#include <gtsam/discrete/DiscreteKey.h>
 
#include <optional>
 
namespace gtsam {

class GTSAM_EXPORT Domain : public Constraint {
  size_t cardinality_;       
  std::set<size_t> values_;  
 
 public:
  typedef std::shared_ptr<Domain> shared_ptr;

  Domain(const DiscreteKey& dkey)
      : Constraint(dkey.first), cardinality_(dkey.second) {
    for (size_t v = 0; v < cardinality_; v++) values_.insert(v);
  }

  Domain(const DiscreteKey& dkey, size_t v)
      : Constraint(dkey.first), cardinality_(dkey.second) {
    values_.insert(v);
  }

  Key key() const { return keys_[0]; }

  DiscreteKey discreteKey() const { return DiscreteKey(key(), cardinality_); }

  void insert(size_t value) { values_.insert(value); }

  void erase(size_t value) { values_.erase(value); }

  uint64_t nrValues() const override { return values_.size(); }

  bool isSingleton() const { return nrValues() == 1; }

  size_t firstValue() const { return *values_.begin(); }

  void print(const std::string& s = "", const KeyFormatter& formatter =
                                            DefaultKeyFormatter) const override;

  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_);
    }
  }

  std::string base1Str() const;

  bool contains(size_t value) const { return values_.count(value) > 0; }

  double evaluate(const Assignment<Key>& values) const override;

  DecisionTreeFactor toDecisionTreeFactor() const override;

  DecisionTreeFactor operator*(const DecisionTreeFactor& f) const override;

  bool ensureArcConsistency(Key j, Domains* domains) const override;

  std::optional<Domain> checkAllDiff(const KeyVector keys,
                                     const Domains& domains) const;

  Constraint::shared_ptr partiallyApply(
      const DiscreteValues& values) const override;

  Constraint::shared_ptr partiallyApply(const Domains& domains) const override;
};
 
}  // namespace gtsam