def __init__(self, mesh, spin, mu_s, mu_s_inv, field, pins,
interactions,
name,
data_saver,
use_jac=False,
integrator='sundials'
):
# Inherit from the driver class
super(SLLG, self).__init__(mesh, spin, mu_s, mu_s_inv, field,
pins, interactions, name,
data_saver,
use_jac=use_jac,
integrator=integrator
)
self._T = np.zeros(self.n, dtype=np.float)
self.next_spin = np.zeros(3*self.n, dtype=np.float)
self.eta = np.zeros(3*self.n, dtype=np.float)
self.dm1 = np.zeros(3*self.n, dtype=np.float)
self.dm2 = np.zeros(3*self.n, dtype=np.float)
self.minor_step = 0
self.mt19937 = clib.rng_mt19937()
self.set_options()
def test_random_sphere(do_plot=False):
"""
test whether spins are uniformly distributed on the surface of a sphere.
"""
mt19937 = clib.rng_mt19937()
mt19937.set_seed(123)
spin = np.zeros(3 * 10000, dtype=np.float)
mt19937.fill_vector_uniform_sphere(spin, 10000)
spin.shape = (-1, 3)
n = spin.shape[0]
x = np.average([spin[i, 0] for i in range(n) if spin[i, 0] > 0])
y = np.average([spin[i, 1] for i in range(n) if spin[i, 1] > 0])
z = np.average([spin[i, 2] for i in range(n) if spin[i, 2] > 0])
print(x, y, z)
print(abs(x - y), abs(x - z), abs(y - z))
assert (abs(x - y) < 4e-3)
assert (abs(x - z) < 4e-3)
assert (abs(y - z) < 4e-3)
if do_plot:
fig = plt.figure()
ax3D = fig.add_subplot(111, projection='3d')
ax3D.scatter(spin[:1000, 0],
spin[:1000, 1],
spin[:1000, 2],
s=30,
marker='.')
plt.savefig('test_random_sphere.png')
def test_random_sphere(do_plot=False):
"""
test whether spins are uniformly distributed on the surface of a sphere.
"""
mt19937 = clib.rng_mt19937()
mt19937.set_seed(123)
spin = np.zeros(3 * 10000, dtype=np.float)
mt19937.fill_vector_uniform_sphere(spin, 10000)
spin.shape = (-1,3)
n = spin.shape[0]
x = np.average([spin[i,0] for i in range(n) if spin[i,0]>0])
y = np.average([spin[i,1] for i in range(n) if spin[i,1]>0])
z = np.average([spin[i,2] for i in range(n) if spin[i,2]>0])
print(x,y,z)
print(abs(x-y), abs(x-z), abs(y-z))
assert(abs(x-y)<4e-3)
assert(abs(x-z)<4e-3)
assert(abs(y-z)<4e-3)
if do_plot:
fig = plt.figure()
ax3D = fig.add_subplot(111, projection='3d')
ax3D.scatter(spin[:1000,0], spin[:1000,1], spin[:1000,2], s=30, marker='.')
plt.savefig('test_random_sphere.png')