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| #!/usr/env python3
# -*- coding: utf-8 -*-
import imgen
imgen.setup()
import matplotlib.pyplot as plt
import numpy as np
from numpy import tanh, cosh, log
fig, ax = plt.subplots(2, 1, sharex=True)
W = np.logspace(0, 10, 100)
mu0 = 1e5
wALI = 100
for B in [0, 1/2, 10, 20, 40]:
r = 1 + mu0 * B
G = mu0 / r
wc = wALI * r
T = G / (1 + 1j*W / wc)
Tc = G / (1 + 1j)
lab = 'B = {:1.1f}'.format(B)
ax[0].loglog(W, np.abs(T), label=lab)
col = ax[0].get_lines()[-1].get_color()
ax[0].loglog([wc, wc], [np.abs(Tc), 0], color=col, linestyle='dashed')
ax[1].plot(W, np.angle(T), label=lab, color=col)
ax[1].axvline(x=wc, color=col, linestyle='dashed')
ax[1].set_xlabel(r'$\omega$')
ax[0].set_ylabel(r'$|T|$')
ax[0].legend()
ax[1].set_ylabel(r'arg($T$)')
ax[1].set_yticks([-np.pi/2, -np.pi/4, 0])
ax[1].set_yticklabels([r'$-\frac{\pi}{2}$', r'$-\frac{\pi}{4}$', '0'])
# Save
imgen.done(__file__)
|