代码练习_随机漫步

matplotlib绘图

from random import choice
import matplotlib.pyplot as plt


class RandomWalk():
    # 自由漫步
    def __init__(self, num_points=50000):
        # 点数量
        self.num_points = num_points
        # 初始点位置
        self.x_values = [0]
        self.y_values = [0]

    def fill_walk(self):
        # 每个随机点
        while len(self.x_values) < self.num_points:
            # 移动的方向和距离
            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 * y_distance
            # 拒绝原地踏步
            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)


while True:
    rw = RandomWalk()
    rw.fill_walk()
    # 点调为渐变色
    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)
    # 放大起始点
    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)
    # 隐藏坐标轴
    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 == 'n':
        break