cylindrical_weight_check.py

import meep as mp
import numpy as np
import matplotlib.pyplot as plt

resolution = 10
r_bank = np.linspace(1.0,1.0+1/resolution,100)
sum_bank = []
for r in r_bank:
    print(r)
    sim = mp.Simulation(
        resolution=resolution,
        cell_size=mp.Vector3(10,0,1),
        dimensions=mp.CYLINDRICAL,
        sources = [mp.Source(mp.ContinuousSource(1),mp.Er,size=mp.Vector3(),center=mp.Vector3(r))],
        m=1,
    )
    sim.init_sim()
    # We need to divide by 2 pi to account for the integral around phi, and then
    # also divide by resolution ** 2 to account for the pixel.
    dV = 1 /( 2 * np.pi * resolution * resolution)
    sum_bank.append(sim.fields.sum_sources(mp.Er) * dV)
    print(f"Sum: {sum_bank[-1]}")
    if r > 0:
        print(f"Ratio: {sum_bank[-1] / r}")
    print("====================================")

plt.figure()
plt.plot(r_bank,np.asarray(r_bank) * 0 + 1,color='k',label='ideal sum of weights')
plt.plot(r_bank,sum_bank, color='r',label='measured sum of weights',linestyle='--')
plt.xlabel("$r$ postion (between two grid points)")
plt.ylabel("sum of weights")
plt.legend()
plt.savefig("weights.png")
plt.show()