Sim.py

'''
IMPORTS
'''
import itertools
import random as rand
import math
import matplotlib.pyplot as plt
import numpy as np
import copy
from Car import Car, Truck, Sedan, SUV, Sport

'''
SIMULATION MECHANISM
'''
class Sim:
    """
    This class represents a traffic Simulation object
    Uses Car objects to represent cars
    """
    def __init__(self):
        self.CAR_LENGTH      = 6      
        self.road_length     = self.CAR_LENGTH * 20 
        self.desired_speed   = 7     
        self.ideal_time      = self.road_length / self.desired_speed      
        
        self.iteration       = 0
        self.cars            = []
        self.init_cars()
        self.avg_speed       = {}
        
        
    def init_cars(self):
        self.cars.append(self.generate_car())

        
    def generate_car(self):
        speed = 6     
        car_chooser = rand.randint(0,3)
        if car_chooser == 0:
            car = Truck()
        elif car_chooser == 1:
            car = SUV()
        elif car_chooser == 2:
            car = Sport()
        else:
            car = Sedan()
            
        car.set_speed(speed)
        return car
    
    
    def step(self):
        if self.cars[0].x > self.road_length:
            self.cars.pop(0)
        
        fender_distance = None
        cars_total_speed = self.cars[0].speed

        if self.CAR_LENGTH * 1.25 < self.cars[-1].x:
            self.cars.append(self.generate_car())

        self.cars[0].drive()
        self.cars[0].incr_speed()
        
        for i in range(len(self.cars)):
            self.cars[i].drive()

            if len(self.cars) != 1 & i != 0:
                fender_dist = self.cars[i - 1].x - self.cars[i].x
                
                self.cars[i].incr_speed()    if fender_dist > self.CAR_LENGTH * 1.25      else None
                self.cars[i].decr_speed()    if fender_dist < self.CAR_LENGTH * 1.25      else None
                self.cars[i].brake()         if fender_dist < self.CAR_LENGTH * 0.625    else None

                cars_total_speed += self.cars[i].speed

                
        self.cars = self.cars[-20:]
        self.avg_speed[self.iteration] = cars_total_speed / len(self.cars)
            
        self.iteration += 1
            
            
    def data_analysis(self):
        self.avg_speed = sorted(self.avg_speed.items())
        x, y = zip(*self.avg_speed)
        plt.plot(x, y)
        plt.xlabel("Simulation iteration")
        plt.ylabel("Average System Speed (mi / h)")
        plt.title("Traffic Simulation w/o ISDs")
        plt.show()