第三课--随机漫步

'''
随机漫步
'''
import matplotlib.pyplot as plt
from random import choice

class RandomWail():
    '''
    生成一个随机漫步的数据
    '''
    def __init__(self,num_points=50000):
        self.num_points = num_points
        self.x_values = [0]
        self.y_values = [0]
    def fill_walk(self):
        while len(self.x_values) < self.num_points:
            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

            #计算下一个点的值
            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)

'''
小试牛刀
'''
# rw = RandomWail()
# rw.fill_walk()
# plt.scatter(rw.x_values, rw.y_values, s=16)
# plt.show()
'''
命令生成漫步图
'''
while True:
    rw = RandomWail()
    rw.fill_walk()
    '''
    画布大小
    '''
    plt.figure(figsize=(10,10))
    '''
    给点上色
    '''
    point_numbers = list(range(rw.num_points))
    plt.scatter(rw.x_values,rw.y_values,c=point_numbers,cmap=plt.cm.Reds,edgecolors='none',s=1)

    '''
    突出起点和重点
    '''
    plt.scatter(0,0,c='green',edgecolors='none',s=100)
    plt.scatter(rw.x_values[-1],rw.y_values[-1],c='yellow',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