import numpy as np

import matplotlib.pyplot as pt

x = np.arange(0, 360)
# 如果打印 x ，NumPy 会给你很好看的打印格式
# print(x)

y = np.sin(x * np.pi / 180)
pt.plot(x, y)
pt.xlim(0, 360)
pt.ylim(-1.2, 1.2)
pt.title("SIN function")

pt.show()

import numpy as np

import matplotlib.pyplot as pt

x = np.arange(0, 360)
y = np.sin(x * np.pi / 180)
z = np.cos(x * np.pi / 180)
pt.plot(x, y, color='blue')
pt.plot(x, z, color='red')

pt.xlim(0, 360)
pt.ylim(-1.2, 1.2)

pt.title("SIN & COS function")

pt.show()

import numpy as np
import matplotlib.pyplot as pt

x = np.arange(0, 360)
print(x)

y = np.sin(2 * x * np.pi / 180.0)
z = np.cos(x * np.pi / 180.0)

# 使用美元符号把标签包围起来，得到 LaTex 公式显示的效果
pt.plot(x, y, color='blue', label="$SIN(2x)$")
pt.plot(x, z, color='red', label="$COS(x)$")

pt.xlim(0, 360)
pt.ylim(-1.2, 1.2)

pt.title("SIN & COS function")
# 要有 pt.legend() 这个方法才会显示图例
pt.legend()
pt.show()