“Ellipse”的版本间差异

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python code
python code
import numpy as np
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import pyplot as plt
from math import pi, cos, sin
u=1. #x-position of the center
from math import pi, cos, sin
###
v=0.5 #y-position of the center
u=1. #x-position of the center
a=2. #radius on the x-axis
v=0.5 #y-position of the center
b=1.5 #radius on the y-axis
t_rot=pi/4 #rotation angle
a=2. #radius on the x-axis

b=1.5 #radius on the y-axis
t = np.linspace(0, 2*pi, 100)
t_rot=pi/4 #rotation angle
Ell = np.array([a*np.cos(t) , b*np.sin(t)])
###
#u,v removed to keep the same center location
t = np.linspace(0, 2*pi, 100)
Ell = np.array([a*np.cos(t) , b*np.sin(t)])
R_rot = np.array([[cos(t_rot) , -sin(t_rot)],[sin(t_rot) , cos(t_rot)]])
#2-D rotation matrix
#u,v removed to keep the same center location

R_rot = np.array([[cos(t_rot) , -sin(t_rot)],[sin(t_rot) , cos(t_rot)]])
Ell_rot = np.zeros((2,Ell.shape[1]))
#2-D rotation matrix
###
for i in range(Ell.shape[1]):
Ell_rot = np.zeros((2,Ell.shape[1]))
Ell_rot[:,i] = np.dot(R_rot,Ell[:,i])

for i in range(Ell.shape[1]):
plt.plot( u+Ell[0,:] , v+Ell[1,:] ) #initial ellipse
Ell_rot[:,i] = np.dot(R_rot,Ell[:,i])
plt.plot( u+Ell_rot[0,:] , v+Ell_rot[1,:],'darkorange' ) #rotated ellipse
###
plt.grid(color='lightgray',linestyle='--')
plt.plot( u+Ell[0,:] , v+Ell[1,:] ) #initial ellipse
plt.show()
plt.plot( u+Ell_rot[0,:] , v+Ell_rot[1,:],'darkorange' ) #rotated ellipse
plt.grid(color='lightgray',linestyle='--')
plt.show()

2019年6月27日 (四) 03:33的最新版本

python code

   import numpy as np
   from matplotlib import pyplot as plt
   from math import pi, cos, sin
   u=1.       #x-position of the center
   v=0.5      #y-position of the center
   a=2.       #radius on the x-axis
   b=1.5      #radius on the y-axis
   t_rot=pi/4 #rotation angle
   t = np.linspace(0, 2*pi, 100)
   Ell = np.array([a*np.cos(t) , b*np.sin(t)])  
        #u,v removed to keep the same center location
   R_rot = np.array([[cos(t_rot) , -sin(t_rot)],[sin(t_rot) , cos(t_rot)]])  
        #2-D rotation matrix
   Ell_rot = np.zeros((2,Ell.shape[1]))
   for i in range(Ell.shape[1]):
       Ell_rot[:,i] = np.dot(R_rot,Ell[:,i])
   plt.plot( u+Ell[0,:] , v+Ell[1,:] )     #initial ellipse
   plt.plot( u+Ell_rot[0,:] , v+Ell_rot[1,:],'darkorange' )    #rotated ellipse
   plt.grid(color='lightgray',linestyle='--')
   plt.show()