class NaSchTraffic(Model):
"""
Model class for the Nagel and Schreckenberg traffic model.
"""
def __init__(self,
height=1,
width=60,
vehicle_quantity=5,
general_max_speed=4,
seed=None):
""""""
super().__init__(seed=seed)
self.height = height
self.width = width
self.vehicle_quantity = vehicle_quantity
self.general_max_speed = general_max_speed
self.schedule = SimultaneousActivation(self)
self.grid = SingleGrid(width, height, torus=True)
self.average_speed = 0.0
self.averages = []
self.total_speed = 0
self.datacollector = DataCollector(
model_reporters={
"Average_Speed": "average_speed"
}, # Model-level count of average speed of all agents
# For testing purposes, agent's individual x position and speed
agent_reporters={
"PosX": lambda x: x.pos[0],
"Speed": lambda x: x.speed,
},
)
# Set up agents
# We use a grid iterator that returns
# the coordinates of a cell as well as
# its contents. (coord_iter)
cells = list(self.grid.coord_iter())
self.random.shuffle(cells)
for vehicle_iter in range(0, self.vehicle_quantity):
cell = cells[vehicle_iter]
(content, x, y) = cell
agent = VehicleAgent((x, y), self, general_max_speed)
self.grid.position_agent(agent, (x, y))
self.schedule.add(agent)
self.running = True
self.datacollector.collect(self)
def step(self):
"""
Run one step of the model. Calculate current average speed of all agents.
"""
if self.schedule.steps == 100:
self.running = False
self.total_speed = 0
# Step all agents, then advance all agents
self.schedule.step()
if self.schedule.get_agent_count() > 0:
self.average_speed = self.total_speed / self.schedule.get_agent_count(
)
else:
self.average_speed = 0
self.averages.append(self.average_speed)
# collect data
self.datacollector.collect(self)
