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matplotlib python plot 3d

How to do a 3D circle in Matplotlib

发布于 2020-03-27 10:18:25

I am a beginner in Python. I'm trying to plot a circle using matplotlib that has tangent to Z axis. I know how to draw a sphere in 3D but don't know how to draw a circle/ring in 3D plot. Can someone help me with the code? Thanks in advance!

gboffi 2019-07-03 21:58

You need the usual imports, plus the 3D toolkit

import matplotlib as mpl
from mpl_toolkits.mplot3d import Axes3D
import numpy as np
import matplotlib.pyplot as plt

You need a 3D enabled axes object

fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')

You need a circle, contained in the plane y-z

theta = np.linspace(0, 2 * np.pi, 201)
y = 10*np.cos(theta)
z = 10*np.sin(theta)

now we can plot the original circle and, as an example, a number of circles rotated about the z-axis and whose centers are also placed at a fixed distance (equal to the c ircles'radius) from the z-axis, so that they are tangent to it

for i in range(18):
    phi = i*np.pi/9
            y*np.cos(phi)+10*np.cos(phi), z)

eventually we place a vertical axis and a legend

ax.plot((0,0),(0,0), (-10,10), '-k', label='z-axis')

It's time to see what we got


enter image description here