Remove unique_id and model.next_id (#194)

All examples can be updated to no longer pass a unique id, nor use model.next_id.

This only fixes the examples, not the gis-examples or rl examples.

Co-authored-by: Ewout ter Hoeven <E.M.terHoeven@student.tudelft.nl>

Author: quaquel

examples/aco_tsp/aco_tsp/model.py

@@ -82,14 +82,13 @@ class AntTSP(mesa.Agent):
     An agent
     """
 
-    def __init__(self, unique_id, model, alpha: float = 1.0, beta: float = 5.0):
+    def __init__(self, model, alpha: float = 1.0, beta: float = 5.0):
         """
         Customize the agent
         """
-        self.unique_id = unique_id
+        super().__init__(model)
         self.alpha = alpha
         self.beta = beta
-        super().__init__(unique_id, model)
         self._cities_visited = []
         self._traveled_distance = 0
         self.tsp_solution = []
@@ -176,8 +175,8 @@ def __init__(
         self.max_steps = max_steps
         self.grid = mesa.space.NetworkGrid(tsp_graph.g)
 
-        for i in range(self.num_agents):
-            agent = AntTSP(unique_id=i, model=self, alpha=ant_alpha, beta=ant_beta)
+        for _ in range(self.num_agents):
+            agent = AntTSP(model=self, alpha=ant_alpha, beta=ant_beta)
 
             city = tsp_graph.cities[self.random.randrange(self.num_cities)]
             self.grid.place_agent(agent, city)

examples/bank_reserves/bank_reserves/agents.py

@@ -45,9 +45,9 @@ def bank_balance(self):
 
 # subclass of RandomWalker, which is subclass to Mesa Agent
 class Person(RandomWalker):
-    def __init__(self, unique_id, model, moore, bank, rich_threshold):
+    def __init__(self, model, moore, bank, rich_threshold):
         # init parent class with required parameters
-        super().__init__(unique_id, model, moore=moore)
+        super().__init__(model, moore=moore)
         # the amount each person has in savings
         self.savings = 0
         # total loan amount person has outstanding

examples/bank_reserves/bank_reserves/model.py

@@ -139,11 +139,11 @@ def __init__(
         self.bank = Bank(self, self.reserve_percent)
 
         # create people for the model according to number of people set by user
-        for i in range(self.init_people):
+        for _ in range(self.init_people):
             # set x, y coords randomly within the grid
             x = self.random.randrange(self.width)
             y = self.random.randrange(self.height)
-            p = Person(i, self, True, self.bank, self.rich_threshold)
+            p = Person(self, True, self.bank, self.rich_threshold)
             # place the Person object on the grid at coordinates (x, y)
             self.grid.place_agent(p, (x, y))
 

examples/bank_reserves/bank_reserves/random_walk.py

@@ -24,15 +24,15 @@ class RandomWalker(mesa.Agent):
     # use a Moore neighborhood
     moore = True
 
-    def __init__(self, unique_id, model, moore=True):
+    def __init__(self, model, moore=True):
         """
         grid: The MultiGrid object in which the agent lives.
         x: The agent's current x coordinate
         y: The agent's current y coordinate
         moore: If True, may move in all 8 directions.
                 Otherwise, only up, down, left, right.
         """
-        super().__init__(unique_id, model)
+        super().__init__(model)
         self.moore = moore
 
     def random_move(self):

examples/boid_flockers/boid_flockers/model.py

@@ -26,7 +26,6 @@ class Boid(mesa.Agent):
 
     def __init__(
         self,
-        unique_id,
         model,
         speed,
         direction,
@@ -40,7 +39,6 @@ def __init__(
         Create a new Boid flocker agent.
 
         Args:
-            unique_id: Unique agent identifier.
             speed: Distance to move per step.
             direction: numpy vector for the Boid's direction of movement.
             vision: Radius to look around for nearby Boids.
@@ -49,7 +47,7 @@ def __init__(
             separate: the relative importance of avoiding close neighbors
             match: the relative importance of matching neighbors' headings
         """
-        super().__init__(unique_id, model)
+        super().__init__(model)
         self.speed = speed
         self.direction = direction
         self.vision = vision
@@ -129,13 +127,12 @@ def make_agents(self):
         """
         Create self.population agents, with random positions and starting headings.
         """
-        for i in range(self.population):
+        for _ in range(self.population):
             x = self.random.random() * self.space.x_max
             y = self.random.random() * self.space.y_max
             pos = np.array((x, y))
             direction = np.random.random(2) * 2 - 1
             boid = Boid(
-                unique_id=i,
                 model=self,
                 speed=self.speed,
                 direction=direction,

examples/boltzmann_wealth_model/boltzmann_wealth_model/model.py

@@ -26,8 +26,8 @@ def __init__(self, N=100, width=10, height=10):
             model_reporters={"Gini": compute_gini}, agent_reporters={"Wealth": "wealth"}
         )
         # Create agents
-        for i in range(self.num_agents):
-            a = MoneyAgent(i, self)
+        for _ in range(self.num_agents):
+            a = MoneyAgent(self)
 
             # Add the agent to a random grid cell
             x = self.random.randrange(self.grid.width)
@@ -50,8 +50,8 @@ def run_model(self, n):
 class MoneyAgent(mesa.Agent):
     """An agent with fixed initial wealth."""
 
-    def __init__(self, unique_id, model):
-        super().__init__(unique_id, model)
+    def __init__(self, model):
+        super().__init__(model)
         self.wealth = 1
 
     def move(self):

examples/boltzmann_wealth_model_experimental/model.py

@@ -26,8 +26,8 @@ def __init__(self, N=100, width=10, height=10):
             model_reporters={"Gini": compute_gini}, agent_reporters={"Wealth": "wealth"}
         )
         # Create agents
-        for i in range(self.num_agents):
-            a = MoneyAgent(i, self)
+        for _ in range(self.num_agents):
+            a = MoneyAgent(self)
 
             # Add the agent to a random grid cell
             x = self.random.randrange(self.grid.width)
@@ -50,8 +50,8 @@ def run_model(self, n):
 class MoneyAgent(mesa.Agent):
     """An agent with fixed initial wealth."""
 
-    def __init__(self, unique_id, model):
-        super().__init__(unique_id, model)
+    def __init__(self, model):
+        super().__init__(model)
         self.wealth = 1
 
     def move(self):

examples/boltzmann_wealth_model_network/boltzmann_wealth_model_network/model.py

@@ -29,7 +29,7 @@ def __init__(self, num_agents=7, num_nodes=10):
 
         # Create agents
         for i in range(self.num_agents):
-            a = MoneyAgent(i, self)
+            a = MoneyAgent(self)
 
             # Add the agent to a random node
             self.grid.place_agent(a, list_of_random_nodes[i])
@@ -50,8 +50,8 @@ def run_model(self, n):
 class MoneyAgent(mesa.Agent):
     """An agent with fixed initial wealth."""
 
-    def __init__(self, unique_id, model):
-        super().__init__(unique_id, model)
+    def __init__(self, model):
+        super().__init__(model)
         self.wealth = 1
 
     def move(self):

examples/caching_and_replay/model.py

@@ -8,16 +8,15 @@ class SchellingAgent(mesa.Agent):
     Schelling segregation agent
     """
 
-    def __init__(self, unique_id, model, agent_type):
+    def __init__(self, model, agent_type):
         """
         Create a new Schelling agent.
 
         Args:
-           unique_id: Unique identifier for the agent.
            x, y: Agent initial location.
            agent_type: Indicator for the agent's type (minority=1, majority=0)
         """
-        super().__init__(unique_id, model)
+        super().__init__(model)
         self.type = agent_type
 
     def step(self):
@@ -84,7 +83,7 @@ def __init__(
         for _, pos in self.grid.coord_iter():
             if self.random.random() < self.density:
                 agent_type = 1 if self.random.random() < self.minority_pc else 0
-                agent = SchellingAgent(self.next_id(), self, agent_type)
+                agent = SchellingAgent(self, agent_type)
                 self.grid.place_agent(agent, pos)
 
         self.datacollector.collect(self)

examples/charts/charts/agents.py

@@ -45,9 +45,9 @@ def bank_balance(self):
 
 # subclass of RandomWalker, which is subclass to Mesa Agent
 class Person(RandomWalker):
-    def __init__(self, unique_id, model, moore, bank, rich_threshold):
+    def __init__(self, model, moore, bank, rich_threshold):
         # init parent class with required parameters
-        super().__init__(unique_id, model, moore=moore)
+        super().__init__(model, moore=moore)
         # the amount each person has in savings
         self.savings = 0
         # total loan amount person has outstanding