使用matplotlib生成随机点阵

1、生成随机点阵

# -*- coding:utf-8 -*-
import matplotlib.pyplot as plt
from random import choice

class RandomWalk():
    """一个生成随机漫步数据的类"""
    def __init__(self, num_points=5000):
        self.num_points = num_points
        #定义起始点
        self.x_values = [0]
        self.y_values = [0]

    def fill_walk(self):
        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 = 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

            if x_step ==0 and y_step == 0: #避免都为零时，原地不动
                continue

            next_x = self.x_values[-1] + x_step # 计算下一个点的值
            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()
    plt.scatter(rw.x_values, rw.y_values, s=15)
    plt.show()

    keep_running = input("Make another one?(y/n)")
    if keep_running == 'n':
        break

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2、表现出路径

想在加上颜色表明哪部分是先画的点，哪里是后面出现的点，即表现出大致路径。

while True:
    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.Reds, s=15)
    plt.show()

    keep_running = input("Make another one?(y/n)")
    if keep_running == 'n':
        break

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3、突出起始点和终点

while True:
    rw = RandomWalk()
    rw.fill_walk()
    point_numbers = list(range(rw.num_points))
    plt.scatter(0, 0, c='green', edgecolors='none', s=105)
    plt.scatter(rw.x_values, rw.y_values, c=point_numbers, cmap=plt.cm.Blues, s=15)
    plt.scatter(rw.x_values[-1], rw.y_values[-1], c='red', edgecolors='none', s=15)
    plt.show()

    keep_running = input("Make another one?(y/n)")
    if keep_running == 'n':
        break

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4、隐藏坐标轴

    plt.axes().get_xaxis().set_visible(False)
    plt.axes().get_yaxis().set_visible(False)

5、调整尺寸以适合屏幕

while True:
    rw = RandomWalk(5000)
    rw.fill_walk()
    point_numbers = list(range(rw.num_points))
    # figure()指定图表的宽度、高度、分辨率和背景色
    plt.figure(dpi=128, figsize=(10, 6))
    plt.scatter(0, 0, c='green', edgecolors='none', s=105)
    plt.scatter(rw.x_values, rw.y_values, c=point_numbers, cmap=plt.cm.Blues, s=15)
    plt.scatter(rw.x_values[-1], rw.y_values[-1], c='red', edgecolors='none', s=15)
    plt.axes().get_xaxis().set_visible(False)
    plt.axes().get_yaxis().set_visible(False)
    plt.show()

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