Python绘制参数方程图

pip install pip-autoremove

 pip-autoremove.exe jupyter -y

pip install jupyter

import matplotlib.pyplot as plt  
from matplotlib import animation  
import numpy as np  
import math  
def xin():  
    t = np.linspace(0, math.pi*2, 1000)  
    # 参数方程的范围
    x = np.cos(3*t)
    y = np.sin(2*t)
    # 参数式
    plt.plot(x, y, color='blue', 
             linewidth=2, label='圆')  
    # 传入x，y，颜色是蓝色，线宽，
    plt.xlabel('t')  
    plt.ylabel('h')  
    # y，x轴的名字
    plt.ylim(-1, 1)  
    plt.xlim(-1.5,1.5)  
    # 坐标轴的长度
    plt.legend()  
    plt.show()  
xin()

    x = np.cos(50*t)
    y = np.sin(39*t)

#半径
r = 2.0
# 圆心
a, b = (0., 0.)
#参数方程
theta = np.arange(0, 2*np.pi, 0.01)
x = a + r * np.cos(theta)
y = b + r * np.sin(theta)

from math import pi
from numpy import cos, sin
from matplotlib import pyplot as plt

if __name__ == '__main__':
    '''plot data margin'''
    angles_circle = [i * pi / 180 for i in range(0, 360)]  # i先转换成double
 
    x = cos(angles_circle)
    y = sin(angles_circle)
    plt.plot(x, y, 'r')

    plt.axis('equal')
    plt.axis('scaled')
    plt.show()

import numpy as np
from matplotlib import pyplot as plt
r=2.0
a,b=0.0,0.0
# 标准方程
x = np.arange(a-r, a+r, 0.01)
y = b + np.sqrt(r**2 - (x - a)**2)

fig = plt.figure() 
axes = fig.add_subplot(111)
axes.plot(x, y) # 上半部
axes.plot(x, -y) # 下半部

axes.axis('equal')

plt.show()

import matplotlib.pyplot as plt
import numpy as np

# create 1000 equally spaced points between -10 and 10
x = np.linspace(-10, 10, 1000)

# calculate the y value for each element of the x vector
y = x**2 + 2*x + 2  

fig, ax = plt.subplots()
ax.plot(x, y)

import matplotlib.pyplot as plt

a=[]
b=[]
# y=0
# x=-50

for x in range(-50,50,1):
    y=x**2+2*x+2
    a.append(x)
    b.append(y)
    #x= x+1

fig= plt.figure()
axes=fig.add_subplot(111)
axes.plot(a,b)
plt.show()

https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.subplot.html

import matplotlib.pyplot as plt
import numpy as np
'''
Set the values in the variable x
The function arange helps to generate an array with the 
following parameters arange(start,end,increment)
'''
x = np.arange(-100,100,1)
'''
Now set the formula in the variable y
'''
y = x**2
'''
Then add the pair (x,y) to the plot
'''
plt.plot(x,y)
'''
Finally show the graph
'''
plt.show()

import numpy as np
import matplotlib.pyplot as plt
x = np.arange(0, 100)
plt.subplot(221)
plt.plot(x, x)
plt.subplot(222)
plt.plot(x, -x)
plt.subplot(223)
plt.plot(x, x ** 2)
plt.subplot(224)
plt.plot(x, np.log(x))
plt.show()

import numpy as np
import matplotlib.pyplot as plt

x = np.arange(0, 100)
# 首先就是生成点列，x
fig = plt.figure()
# 创建一个大的画布
ax1 = fig.add_subplot(221)
ax1.plot(x, x)
# 第一个图，直接221的位置
ax2 = fig.add_subplot(222)
ax2.plot(x, -x)
# 222的位置，-的斜率
ax3 = fig.add_subplot(223)
ax3.plot(x, x ** 2)
# 二次函数
ax4 = fig.add_subplot(224)
ax4.plot(x, np.log(x))
# 对数形式
plt.show()