from random import choice class RandomWalk(): """一個生成隨機漫步數據的類"""  def __init__(self,num_points=5000): """初始化隨機漫步的屬性""" self.num_points = num_points  #所有隨機漫步都始于(0,0) self.x_values = [0] self.y_values = [0]  def fill_walk(self): """計算隨機漫步包含的所有點"""  #不斷漫步，直到列表達到指定的長度 while len(self.x_values) < self.num_points:  # 決定前進方向以及沿這個方向前進的距離  x_direction = choice([1,-1])  x_distance = choice([0,1,2,3,4])  x_step = x_direction * x_distance   y_direction = choice([1,-1])  y_distance = choice([0,1,2,3,4])  y_step = y_direction * x_distance   # 拒絕原地踏步  if x_step == 0 and y_step == 0:  continue   #計算下一個點的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) 

import matplotlib.pyplot as plt  from random_walk import RandomWalk # 創建一個RandomWalk實例，并將其包含的點都繪制出來rw = RandomWalk(50000)rw.fill_walk() # 設置繪圖窗口的尺寸plt.figure(dpi=80,figsize=(10,6)) # 設置點按先后順序增加顏色深度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=1) # 突出起點和終點，起點設置為綠色，終點設置為紅色plt.scatter(0,0,c='green',edgecolor='none',s=100)plt.scatter(rw.x_values[-1],rw.y_values[-1],c='red',edgecolor='none',s=100) # 隱藏坐標軸plt.axes().get_xaxis().set_visible(False)plt.axes().get_yaxis().set_visible(False) plt.show()