Use a map to represent payoffs

Author: tturocy

src/games/game.cc

@@ -41,9 +41,11 @@ namespace Gambit {
 //                       class GameOutcomeRep
 //========================================================================
 
-GameOutcomeRep::GameOutcomeRep(GameRep *p_game, int p_number)
-  : m_game(p_game), m_number(p_number), m_payoffs(m_game->NumPlayers())
+GameOutcomeRep::GameOutcomeRep(GameRep *p_game, int p_number) : m_game(p_game), m_number(p_number)
 {
+  for (const auto &player : p_game->GetPlayers()) {
+    m_payoffs[player] = Number();
+  }
 }
 
 //========================================================================

src/games/game.h

@@ -121,7 +121,7 @@ class GameOutcomeRep : public GameObject {
   GameRep *m_game;
   int m_number;
   std::string m_label;
-  Array<Number> m_payoffs;
+  std::map<GamePlayerRep *, Number> m_payoffs;
 
   /// @name Lifecycle
   //@{
@@ -145,7 +145,6 @@ class GameOutcomeRep : public GameObject {
 
   /// Gets the payoff associated with the outcome to the player
   template <class T> const T &GetPayoff(const GamePlayer &p_player) const;
-
   /// Sets the payoff to the player
   void SetPayoff(const GamePlayer &p_player, const Number &p_value);
   //@}
@@ -586,27 +585,31 @@ inline Game GameOutcomeRep::GetGame() const { return m_game; }
 
 template <class T> const T &GameOutcomeRep::GetPayoff(const GamePlayer &p_player) const
 {
-  if (p_player->GetGame() != GetGame()) {
+  try {
+    return static_cast<const T &>(m_payoffs.at(p_player));
+  }
+  catch (const std::out_of_range &) {
     throw MismatchException();
   }
-  return static_cast<const T &>(m_payoffs[p_player->GetNumber()]);
 }
 
 template <> inline const Number &GameOutcomeRep::GetPayoff(const GamePlayer &p_player) const
 {
-  if (p_player->GetGame() != GetGame()) {
+  try {
+    return m_payoffs.at(p_player);
+  }
+  catch (const std::out_of_range &) {
     throw MismatchException();
   }
-  return m_payoffs[p_player->GetNumber()];
 }
 
 inline void GameOutcomeRep::SetPayoff(const GamePlayer &p_player, const Number &p_value)
 {
   if (p_player->GetGame() != GetGame()) {
     throw MismatchException();
   }
+  m_payoffs[p_player] = p_value;
   m_game->IncrementVersion();
-  m_payoffs[p_player->GetNumber()] = p_value;
 }
 
 inline GamePlayer GameStrategyRep::GetPlayer() const { return m_player; }

src/games/gametable.cc

@@ -392,7 +392,7 @@ GamePlayer GameTableRep::NewPlayer()
   auto player = new GamePlayerRep(this, m_players.size() + 1, 1);
   m_players.push_back(player);
   for (auto outcome : m_outcomes) {
-    outcome->m_payoffs.push_back(Number());
+    outcome->m_payoffs[player] = Number();
   }
   return player;
 }

src/games/gametree.cc

@@ -968,11 +968,10 @@ int GameTreeRep::BehavProfileLength() const
 GamePlayer GameTreeRep::NewPlayer()
 {
   IncrementVersion();
-  GamePlayerRep *player = nullptr;
-  player = new GamePlayerRep(this, m_players.size() + 1);
+  auto player = new GamePlayerRep(this, m_players.size() + 1);
   m_players.push_back(player);
   for (auto &outcome : m_outcomes) {
-    outcome->m_payoffs.push_back(Number());
+    outcome->m_payoffs[player] = Number();
   }
   ClearComputedValues();
   return player;

src/pygambit/outcome.pxi

@@ -85,9 +85,7 @@ class Outcome:
         resolved_player = cython.cast(Player,
                                       self.game._resolve_player(player, "Outcome.__getitem__"))
         payoff = (
-            cython.cast(bytes,
-                        self.outcome.deref().GetPayoff[string](resolved_player.player))
-            .decode("ascii")
+            self.outcome.deref().GetPayoff[string](resolved_player.player).decode("ascii")
         )
         if "." in payoff:
             return decimal.Decimal(payoff)