python绘制随机漫步图遇到的Error

学习用python绘制随机漫步图遇到的Error

#random_walk.py :
from random import choice
class RandomWalk:
    def __init__(self,num_points=5000):
        self.num_points= num_points
        self.x_values = (0)
        self.y_values = (0)
    def fill_walk(self):
        while len(str(self.x_values)) < self.num_points:
            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
            if x_step ==0 and y_step == 0:
                continue
            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)

#rw_visual.py:
import matplotlib.pyplot as plt
from random_walk import  RandomWalk
rw = RandomWalk()
rw.fill_walk()
fig.ax = plt.subplots()
ax.scatter(rw.x_values,rw.y_values,s=15)
plt.show()

运行rw_visual.py结果
Traceback (most recent call last):
  File "D:\projects\数据可视化\rw_visual.py", line 4, in <module>
    rw.fill_walk()
  File "D:\projects\数据可视化\random_walk.py", line 17, in fill_walk
    next_x = self.x_values[-1] + x_step
             ~~~~~~~~~~~~~^^^^
TypeError: 'int' object is not subscriptable

望采纳，已经写好代码如下：

import random
import matplotlib.pyplot as plt

# 随机漫步图类
class RandomWalk:
    def __init__(self, num_points=5000):
        self.num_points = num_points

        # 所有随机漫步都始于(0, 0)
        self.x_values = [0]
        self.y_values = [0]

    # 漫步
    def fill_walk(self):
        # 不断漫步，直到列表达到指定的长度
        while len(self.x_values) < self.num_points:
            # 决定前进方向以及沿这个方向前进的距离
            x_direction = random.choice([1, -1])
            x_distance = random.choice([0, 1, 2, 3, 4])
            x_step = x_direction * x_distance

            y_direction = random.choice([1, -1])
            y_distance = random.choice([0, 1, 2, 3, 4])
            y_step = y_direction * y_distance

            # 拒绝原地踏步
            if x_step == 0 and y_step == 0:
                continue

            # 计算下一个点的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)

# 绘制随机漫步图
rw = RandomWalk()
rw.fill_walk()

plt.scatter(rw.x_values, rw.y_values, s=15)
plt.show()

        self.x_values = (0)
        self.y_values = (0)
改为
        self.x_values = (0,)
        self.y_values = (0,)