可以在循环中使用条件语句来检查数组中元素的值，并根据指定的条件分配不同的标记

import matplotlib.pyplot as plt

i = [0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50]
j = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

for x,y in zip(i,j):
    if x <=20:
        plt.scatter(x,y,c='red',marker='o')
    elif x <=40:
        plt.scatter(x,y,c='blue',marker='^')
    else:
        plt.scatter(x,y,c='green',marker='s')

plt.show()