Add cell-centric discrete spaces (experimental)

benchmarks/Schelling/schelling.py

@@ -1,14 +1,14 @@
-from mesa import Agent, Model
-from mesa.space import SingleGrid
+from mesa import Model
+from mesa.experimental.cell_space import CellAgent, OrthogonalGrid
 from mesa.time import RandomActivation
 
 
-class SchellingAgent(Agent):
+class SchellingAgent(CellAgent):
     """
     Schelling segregation agent
     """
 
-    def __init__(self, unique_id, model, agent_type):
+    def __init__(self, unique_id, model, agent_type, radius):
         """
         Create a new Schelling agent.
         Args:
@@ -18,18 +18,17 @@ def __init__(self, unique_id, model, agent_type):
         """
         super().__init__(unique_id, model)
         self.type = agent_type
+        self.radius = radius
 
     def step(self):
         similar = 0
-        for neighbor in self.model.grid.iter_neighbors(
-            self.pos, moore=True, radius=self.model.radius
-        ):
+        for neighbor in self.cell.neighborhood(radius=self.radius).agents:
             if neighbor.type == self.type:
                 similar += 1
 
         # If unhappy, move:
         if similar < self.model.homophily:
-            self.model.grid.move_to_empty(self)
+            self.move_to(self.model.grid.select_random_empty_cell())
         else:
             self.model.happy += 1
 
@@ -49,22 +48,21 @@ def __init__(
         self.density = density
         self.minority_pc = minority_pc
         self.homophily = homophily
-        self.radius = radius
 
         self.schedule = RandomActivation(self)
-        self.grid = SingleGrid(height, width, torus=True)
+        self.grid = OrthogonalGrid(height, width, torus=True, capacity=1)
 
         self.happy = 0
 
         # Set up agents
         # We use a grid iterator that returns
         # the coordinates of a cell as well as
         # its contents. (coord_iter)
-        for _cont, pos in self.grid.coord_iter():
+        for cell in self.grid:
             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)
-                self.grid.place_agent(agent, pos)
+                agent = SchellingAgent(self.next_id(), self, agent_type, radius)
+                agent.move_to(cell)
                 self.schedule.add(agent)
 
     def step(self):