I have the following issue. I have a function of two variables defined on a regular grid via np.meshgrid and I would like to get the coordinates of the points on some contour, within a bounding region given by a polygon.

The relevant code for this is the following:

import numpy as np
import numpy.linalg as linalg
import matplotlib.pyplot as plt
from matplotlib.patches import RegularPolygon


def H_tau_1(kx,ky):
    return -t*(1 + np.exp( 2j*(1/2)*kx) )
def H_tau_2(kx,ky):
    return -t*(1 + np.exp(2j*((1/4)*kx + (np.sqrt(3)/4)*ky) ) )
def H_tau_3(kx,ky):
    return -t*(1 + np.exp(2j*( (-1/4)*kx + (np.sqrt(3)/4)*ky) ) )
def mu_grid(mu,kx,ky):
    return mu*np.ones((kx.shape[0],ky.shape[0]))
def xi(mu,kx,ky):
    H_mat = np.array([
        [-mu_grid(mu,kx,ky), -t*(1 + np.exp(2j*( (-1/4)*kx + (np.sqrt(3)/4)*ky) ) ), -t*(1 + np.exp(-2j*(1/2)*kx) )],
        [-t*(1 + np.exp(-2j*( (-1/4)*kx + (np.sqrt(3)/4)*ky) ) ), -mu_grid(mu,kx,ky), -t*(1 + np.exp(-2j*((1/4)*kx + (np.sqrt(3)/4)*ky) ) )],
        [-t*(1 + np.exp(2j*(1/2)*kx) ),-t*(1 + np.exp(2j*((1/4)*kx + (np.sqrt(3)/4)*ky) ) ),-mu_grid(mu,kx,ky)]
                                                                
    ])

t=1
klin = np.linspace(-1,1,2*Nk+1)[1:]*2*(np.pi)
kx,ky= np.meshgrid(klin,klin)
xii = xi(mu,kx,ky)
Nk = 100

figc,axc=plt.subplots()

cs=axc.contour(kx,ky,xii[:,:,1],[0.2],colors='blue')
radius=linalg.norm([0,2*np.pi/np.sqrt(3)])/(np.sqrt(3)/2)
hexagon = RegularPolygon(([0,0]), numVertices=6, radius=radius, edgecolor='k',fill=False)
axc.add_patch(hexagon)
cs.set_clip_path(hexagon)
plt.show()

I understand that cs.set_clip_path(hexagon) is only used for plotting purposes. Is there a way to get the coordinates given by cs.allsegs for the contours inside the hexagon? Output without cs.set_clip_path(hexagon).. That is, the coordinates of the contour given by the following plot (.png)

Thanks a lot!