from random import choice
 
class RandomWalk():
 "一個(gè)生成隨機(jī)漫步數(shù)據(jù)的表"
 
 def __init__(self, num_points = 5000):
 """初始化隨機(jī)漫步的屬性"""
 self.num_points = num_points
 
 # 所有隨機(jī)漫步都起始于(0, 0)
 self.x_values = [0]
 self.y_values = [0]
 
 def fill_walk(self):
 """計(jì)算隨機(jī)漫步包含的所有點(diǎn)"""
 
 # 不斷漫步，直到列表達(dá)到指定的長(zhǎng)度
 while len(self.x_values) < self.num_points:
 
  # 決定前進(jìn)的方向以及沿這個(gè)方向前進(jìn)的距離
  x_direction = choice([-1, 1])
  x_distance = choice([0, 1, 2, 3, 4])
  x_step = x_distance * x_direction 
 
  y_direction = choice([-1, 1])
  y_distance = choice([0, 1, 2, 3, 4])
  y_step = y_distance * y_direction
 
  # 拒絕原地踏步
  if x_step == 0 and y_step == 0:
  continue
 
  # 計(jì)算下一個(gè)點(diǎn)的x和y值
  next_x = self.x_values[-1] + x_step
  next_y = self.y_values[-1] + y_step
 
  self.x_values.append(next_x)
  self.y_values.append(next_y)

from random_walk import RandomWalk
 
# 不斷的模擬隨機(jī)漫步
while True:
 # 創(chuàng)建一個(gè)RandomWalk實(shí)例，將其包含的點(diǎn)繪制出來(lái)
 rw = RandomWalk()
 rw.fill_walk()
 
 
 point_numbers = list(range(rw.num_points))
 plt.scatter(rw.x_values, rw.y_values, c = point_numbers, cmap = plt.cm.Blues, 
 edgecolor = 'none', s = 5)
 
 # 突出起點(diǎn)和終點(diǎn)
 plt.scatter(0, 0, c='green', edgecolors = 'none', s = 100)
 plt.scatter(rw.x_values[1], rw.y_values[-1], c = 'red', edgecolors = 'none', s = 100)
 
 # 隱藏坐標(biāo)軸
 # plt.axes().get_xaxis().set_visible(False)
 # plt.axes().get_yaxis().set_visible(False)
 
 plt.show()
 
 keep_running = input("Make another walk? (y/n): ")
 if keep_running.lower().startswith('n'):
 break