Signature.cpp

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/* ----------------------------------------------------------------------------

 * GTSAM Copyright 2010, Georgia Tech Research Corporation,
 * Atlanta, Georgia 30332-0415
 * All Rights Reserved
 * Authors: Frank Dellaert, et al. (see THANKS for the full author list)

 * See LICENSE for the license information

 * -------------------------------------------------------------------------- */

#include "Signature.h"

#include <cassert>
#include <sstream>

#include "gtsam/discrete/SignatureParser.h"

namespace gtsam {

using namespace std;

ostream& operator<<(ostream& os, const Signature::Row& row) {
  os << row[0];
  for (size_t i = 1; i < row.size(); i++) os << " " << row[i];
  return os;
}

ostream& operator<<(ostream& os, const Signature::Table& table) {
  for (size_t i = 0; i < table.size(); i++) os << table[i] << endl;
  return os;
}

Signature::Signature(const DiscreteKey& key, const DiscreteKeys& parents,
                     const Table& table)
    : key_(key), parents_(parents) {
  operator=(table);
}

Signature::Signature(const DiscreteKey& key, const DiscreteKeys& parents,
                     const std::string& spec)
    : key_(key), parents_(parents) {
  operator=(spec);
}

Signature::Signature(const DiscreteKey& key) : key_(key) {}

DiscreteKeys Signature::discreteKeys() const {
  DiscreteKeys keys;
  keys.push_back(key_);
  for (const DiscreteKey& key : parents_) keys.push_back(key);
  return keys;
}

KeyVector Signature::indices() const {
  KeyVector js;
  js.push_back(key_.first);
  for (const DiscreteKey& key : parents_) js.push_back(key.first);
  return js;
}

vector<double> Signature::cpt() const {
  vector<double> cpt;
  if (table_) {
    const size_t nrStates = table_->at(0).size();
    for (size_t j = 0; j < nrStates; j++) {
      for (const Row& row : *table_) {
        assert(row.size() == nrStates);
        cpt.push_back(row[j]);
      }
    }
  }
  return cpt;
}

Signature &Signature::operator,(const DiscreteKey& parent) {
  parents_.push_back(parent);
  return *this;
}

static void normalize(Signature::Row& row) {
  double sum = 0;
  for (size_t i = 0; i < row.size(); i++) sum += row[i];
  for (size_t i = 0; i < row.size(); i++) row[i] /= sum;
}

Signature& Signature::operator=(const string& spec) {
  spec_ = spec;
  auto table = SignatureParser::Parse(spec);
  if (table) {
    for (Row& row : *table) normalize(row);
    table_ = *table;
  }
  return *this;
}

Signature& Signature::operator=(const Table& t) {
  Table table = t;
  for (Row& row : table) normalize(row);
  table_ = table;
  return *this;
}

ostream& operator<<(ostream& os, const Signature& s) {
  os << s.key_.first;
  if (s.parents_.empty()) {
    os << " % ";
  } else {
    os << " | " << s.parents_[0].first;
    for (size_t i = 1; i < s.parents_.size(); i++)
      os << " && " << s.parents_[i].first;
    os << " = ";
  }
  os << (s.spec_ ? *s.spec_ : "no spec") << endl;
  if (s.table_)
    os << (*s.table_);
  else
    os << "spec could not be parsed" << endl;
  return os;
}

Signature operator|(const DiscreteKey& key, const DiscreteKey& parent) {
  Signature s(key);
  return s, parent;
}

Signature operator%(const DiscreteKey& key, const string& parent) {
  Signature s(key);
  return s = parent;
}

Signature operator%(const DiscreteKey& key, const Signature::Table& parent) {
  Signature s(key);
  return s = parent;
}

}  // namespace gtsam