def test_current_push():
NX = 32 #const.NX
xmin = 0.0 #const.xmin
xmax = 2*np.pi #const.xmax
k = 1.0
marker_size = 20
dx = xmax / NX
x = np.arange(xmin, xmax, dx/100.)
E_nodes = (np.arange(NX + 3) - 0.5) * dx
B_nodes = (np.arange(NX + 3) - 1.0) * dx
E_in = np.zeros((NX + 3, 3))
J_in = np.zeros((NX + 3, 3))
L_in = np.ones((NX + 3)) # Charge-like (const.)
G_in = np.ones((NX + 3, 3)) # Current-like (const.)
Be = np.zeros((NX + 3, 3))
Be[:, 0] = np.sin(1.0*E_nodes*k)
Be[:, 1] = np.sin(2.0*E_nodes*k)
Be[:, 2] = np.sin(3.0*E_nodes*k)
B = np.zeros((NX + 3, 3))
B[:, 0] = np.sin(1.0*B_nodes*k)
B[:, 1] = np.sin(2.0*B_nodes*k)
B[:, 2] = np.sin(3.0*B_nodes*k)
DT = 2.0
J_out = sources.push_current(J_in, E_in, B, L_in, G_in, DT)
J_an = np.zeros((NX + 3, 3))
J_an[:, 0] = Be[:, 2] - Be[:, 1]
J_an[:, 1] = Be[:, 0] - Be[:, 2]
J_an[:, 2] = Be[:, 1] - Be[:, 0]
if True:
plt.figure()
plt.scatter(E_nodes, J_an[:, 0], s=marker_size, c='k', marker='o')
plt.scatter(E_nodes, J_an[:, 1], s=marker_size, c='k', marker='o')
plt.scatter(E_nodes, J_an[:, 2], s=marker_size, c='k', marker='o')
plt.scatter(E_nodes, J_out[:, 0], s=marker_size, c='r', marker='x')
plt.scatter(E_nodes, J_out[:, 1], s=marker_size, c='r', marker='x')
plt.scatter(E_nodes, J_out[:, 2], s=marker_size, c='r', marker='x')
for kk in range(NX + 3):
plt.axvline(E_nodes[kk], linestyle='--', c='r', alpha=0.2)
plt.axvline(B_nodes[kk], linestyle='--', c='b', alpha=0.2)
plt.axvline(xmin, linestyle='-', c='k', alpha=0.2)
plt.axvline(xmax, linestyle='-', c='k', alpha=0.2)
plt.xlim(xmin - 1.5*dx, xmax + 2*dx)
plt.legend()
return
qq = 0
while qq < max_inc:
part, qq, DT, max_inc, data_dump_iter, plot_dump_iter, change_flag = aux.check_timestep(
qq, DT, part, B, E, dns_int, max_inc, data_dump_iter,
plot_dump_iter)
if change_flag == 1:
print(
'Timestep halved. Syncing particle velocity/position with DT = {}'
.format(DT))
part, dns_int, dns_half, J_plus, J_minus, G, L = sources.init_collect_moments(
part, 0.5 * DT)
B = fields.cyclic_leapfrog(B, dns_int, J_minus, DT)
E = fields.calculate_E(B, J_minus, dns_half)
J = sources.push_current(J_plus, E, B, L, G, DT)
E = fields.calculate_E(B, J, dns_half)
part = particles.velocity_update(part, B, E, DT)
part, dns_int, J_plus, J_minus, G, L = sources.collect_moments(
part, DT)
dns_int = 0.5 * (dns_int + dns_half)
J = 0.5 * (J_plus + J_minus)
B = fields.cyclic_leapfrog(B, dns_int, J, DT)
if qq % data_dump_iter == 0 and generate_data == 1: # Save data, if flagged
pas.save_data(DT, data_dump_iter, qq, part, J, E, B, dns_int)
if qq % plot_dump_iter == 0 and generate_plots == 1: # Generate and save plots, if flagged