Python Sim.run_until方法代码示例

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def relax_system_stage2():

    mesh = CuboidMesh(nx=140 , ny=140, nz=1)

    sim = Sim(mesh, name='dyn', driver='llg')
    sim.alpha = 0.1
    sim.do_precession = True
    sim.gamma = const.gamma
    sim.mu_s = spatial_mu

    sim.set_m(np.load('skx.npy'))

    J = 50 * const.k_B
    exch = UniformExchange(J)
    sim.add(exch)

    D = 0.27 * J
    dmi = DMI(D)
    sim.add(dmi)

    zeeman = Zeeman(spatial_H)
    sim.add(zeeman)

    ts = np.linspace(0, 2e-9, 201)
    for t in ts:
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
        print(t)

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def excite_system(mesh):

    sim = Sim(mesh, name='dyn')

    # sim.set_options(rtol=1e-10,atol=1e-14)
    sim.driver.alpha = 0.04
    sim.driver.gamma = 1.0
    sim.mu_s = 1.0

    sim.set_m(np.load('m0.npy'))

    J = 1.0
    exch = UniformExchange(J)
    sim.add(exch)

    D = 0.09
    dmi = DMI(D)
    sim.add(dmi)

    zeeman = Zeeman([0, 0, 3.75e-3], name='H')
    sim.add(zeeman)

    w0 = 0.02

    def time_fun(t):
        return np.exp(-w0 * t)

    hx = TimeZeeman([0, 0, 1e-5], sinc_fun, name='h')
    sim.add(hx, save_field=True)

    ts = np.linspace(0, 20000, 5001)
    for t in ts:
        sim.run_until(t)
        print 'sim t=%g' % t

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def excite_system(mesh, Hy=0):

    sim = Sim(mesh, name="dyn")

    sim.set_options(rtol=1e-10, atol=1e-12)
    sim.alpha = 0.04
    sim.gamma = 1.0
    sim.mu_s = 1.0

    sim.set_m(np.load("m0.npy"))

    J = 1.0
    exch = UniformExchange(J)
    sim.add(exch)

    D = 0.18
    dmi = DMI(D)
    sim.add(dmi)

    zeeman = Zeeman([0, Hy, 2e-2], name="H")
    sim.add(zeeman)

    hx = TimeZeeman([0, 0, 1e-5], sinc_fun, name="h")
    sim.add(hx, save_field=True)

    dt = 5
    steps = 2001
    for i in range(steps):

        sim.run_until(i * dt)

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def relax_system(mesh, Dx=0.005, Dp=0.01):

    mat = UnitMaterial()

    sim = Sim(mesh, name='test_energy')
    print('Created sim')
    sim.set_tols(rtol=1e-10, atol=1e-12)

    sim.alpha = mat.alpha
    sim.gamma = mat.gamma
    sim.pins = pin_fun

    exch = UniformExchange(mat.J)
    sim.add(exch)
    print('Added UniformExchange')

    anis = Anisotropy(Dx, axis=[1, 0, 0], name='Dx')
    sim.add(anis)
    print('Added Anisotropy')

    anis2 = Anisotropy([0, 0, -Dp], name='Dp')
    sim.add(anis2)
    print('Added Anisotropy 2')

    sim.set_m((1, 1, 1))

    T = 100
    ts = np.linspace(0, T, 201)
    for t in ts:
        # sim.save_vtk()
        sim.run_until(t)
        print('Running -', t)

    # sim.save_vtk()
    np.save('m0.npy', sim.spin)

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def excite_system(T=0.1, H=0.15):

    mesh = CuboidMesh(nx=28 * 3, ny=16 * 5, nz=1, pbc='2d')

    sim = Sim(mesh, name='dyn', driver='sllg')
    sim.set_options(dt=1e-14, gamma=const.gamma, k_B=const.k_B)
    sim.alpha = 0.1
    sim.mu_s = const.mu_s_1

    sim.set_m(random_m)

    J = 50 * const.k_B
    exch = UniformExchange(J)
    sim.add(exch)

    D = 0.5 * J
    dmi = DMI(D)
    sim.add(dmi)

    Hz = H * J / const.mu_s_1
    zeeman = Zeeman([0, 0, Hz])
    sim.add(zeeman)

    sim.T = J / const.k_B * T

    ts = np.linspace(0, 5e-11, 51)
    for t in ts:
        sim.run_until(t)
        # sim.save_vtk()

    np.save('m.npy', sim.spin)
    plot_m(mesh, 'm.npy', comp='z')

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def dynamic(mesh):

    sim = Sim(mesh, name='dyn', driver='slonczewski')
    # sim.set_options(rtol=1e-10,atol=1e-14)
    sim.gamma = 1.0
    sim.mu_s = 1.0

    sim.set_m(np.load('m0.npy'))

    J = 1.0
    exch = UniformExchange(J)
    sim.add(exch)

    Kx = Anisotropy(Ku=0.005, axis=(1, 0, 0), name='Kx')
    sim.add(Kx)

    sim.p = (0,0,1)

    sim.u0 = 0.03
    sim.alpha = 0.1

    ts = np.linspace(0, 1e3, 101)
    for t in ts:
        sim.run_until(t)
        sim.save_vtk()
        print t

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def excite_system(mesh):

    sim = Sim(mesh, name='dyn', driver='sllg')
    sim.set_options(dt=1e-14, gamma=const.gamma, k_B=const.k_B)
    sim.driver.alpha = 0.1
    sim.mu_s = const.mu_s_1
    sim.T = temperature_gradient

    sim.set_m(np.load("m0.npy"))

    J = 50.0 * const.k_B
    exch = UniformExchange(J)
    sim.add(exch)

    D = 0.5 * J
    dmi = DMI(D)
    sim.add(dmi)

    Hz = 0.2 * J / const.mu_s_1
    zeeman = Zeeman([0, 0, Hz])
    sim.add(zeeman)

    dt = 2e-14 * 50  # 1e-12
    ts = np.linspace(0, 1000 * dt, 501)
    for t in ts:
        sim.run_until(t)
        sim.save_vtk()
        sim.save_m()
        print 'sim t=%g' % t

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def test_dynamic():

    mesh = CuboidMesh(nx=1, ny=1, nz=1)

    sim = Sim(mesh, name='dyn_spin', driver='slonczewski')
    # sim.set_options(rtol=1e-10,atol=1e-14)
    sim.gamma = 1.0
    sim.mu_s = 1.0

    sim.set_m((0.8,0,-1))

    Kx = Anisotropy(Ku=-0.05, axis=(0, 0, 1), name='Kz')
    sim.add(Kx)

    sim.p = (0,0,1)

    sim.a_J = 0.0052
    sim.alpha = 0.1

    ts = np.linspace(0, 1200, 401)
    for t in ts:
        sim.run_until(t)


    mz = sim.spin[2]
    alpha, K, u = 0.1, 0.05, 0.0052
    print(mz, u/(2*alpha*K))

    #########################################################
    # The system used in this test can be solved analytically, which gives that mz = u/(2*alpha*K),
    # where K represents the easy-plane anisotropy.
    ###
    assert abs(mz - u/(2*alpha*K))/mz< 5e-4

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def test_sim_pin():
    mesh = CuboidMesh(nx=3, ny=2, nz=1)
    sim = Sim(mesh)
    sim.set_m((0, 0.8, 0.6))
    sim.alpha = 0.1
    sim.gamma = 1.0
    sim.pins = pin_fun

    anis = Anisotropy(Ku=1.0, axis=[0, 0, 1], name='Dx')
    sim.add(anis)

    sim.run_until(1.0)
    assert sim.spin[0] == 0
    assert sim.spin[2] != 0

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def test_sim_spins(do_plot=False):

    mesh = CuboidMesh(nx=10, ny=5, nz=1)

    sim = Sim(mesh, name='10spin')

    alpha = 0.1
    gamma = 2.21e5
    sim.alpha = alpha
    sim.gamma = gamma
    sim.mu_s = 1.0

    sim.set_m((1, 0, 0))
    print(sim.spin)

    H0 = 1e5
    sim.add(Zeeman((0, 0, H0)))

    ts = np.linspace(0, 1e-9, 101)

    mx = []
    my = []
    mz = []
    real_ts = []

    for t in ts:
        sim.run_until(t)
        real_ts.append(sim.t)
        #print sim.t, abs(sim.spin_length()[0] - 1)
        av = sim.compute_average()
        mx.append(av[0])
        my.append(av[1])
        mz.append(av[2])

        #sim.save_vtk()

    mz = np.array(mz)
    # print mz
    a_mx, a_my, a_mz = single_spin(alpha, gamma, H0, ts)

    print(sim.stat())

    if do_plot:
        plot(real_ts, mx, my, mz, a_mx, a_my, a_mz, name='spins.pdf', title='integrating spins')

    print(("Max Deviation = {0}".format(
        np.max(np.abs(mz - a_mz)))))

    assert np.max(np.abs(mz - a_mz)) < 5e-7

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def disable_test_sim_single_spin_llg_stt(do_plot=False):
    ni = Nickel()
    mesh = CuboidMesh(nx=1, ny=1, nz=1)
    mesh.set_material(ni)

    ni.alpha = 0.1
    sim = Sim(mesh, driver='llg_stt')
    sim.set_m((1, 0, 0))

    H0 = 1
    sim.add(Zeeman((0, 0, H0)))

    dt = 1e-12
    ts = np.linspace(0, 200 * dt, 101)

    precession = ni.gamma / (1 + ni.alpha**2)

    mz_ref = []
    mxyz = []
    real_ts = []

    for t in ts:
        sim.run_until(t)
        real_ts.append(sim.t)
        print(sim.t, abs(sim.spin_length()[0] - 1), sim.spin)
        mz_ref.append(np.tanh(precession * ni.alpha * H0 * sim.t))
        mxyz.append(np.copy(sim.spin))

    mxyz = np.array(mxyz)

    if do_plot:
        ts_ns = np.array(real_ts) * 1e9

        plt.plot(ts_ns, mxyz[:, 0], ".-", label="mx")
        plt.plot(ts_ns, mxyz[:, 1], ".-", label="my")
        plt.plot(ts_ns, mxyz[:, 2], ".-", label="mz")
        plt.plot(ts_ns, mz_ref, "-", label="analytical")
        plt.xlabel("time (ns)")
        plt.ylabel("mz")
        plt.title("integrating a macrospin")
        plt.legend()
        plt.savefig("test_llg_stt.png")

        print(("Deviation = {0}".format(np.max(np.abs(mxyz[:, 2] - mz_ref)))))

    assert np.max(np.abs(mxyz[:, 2] - mz_ref)) < 1e-9

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def relax_system(rtol=1e-10, atol=1e-12):
    """numerical solution"""
    mesh = CuboidMesh(nx=1, ny=1, nz=1)
    sim = Sim(mesh, name="relax")
    sim.set_options(rtol=rtol, atol=atol)
    sim.alpha = 0.5
    sim.gamma = 2.21e5
    sim.mu_s = 1.0

    sim.set_m((1.0, 0, 0))

    sim.add(Zeeman((0, 0, 1e5)))

    ts = np.linspace(0, 1e-9, 1001)

    for t in ts:
        sim.run_until(t)

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def test_sim_single_spin_sllg(do_plot=False):

    mesh = CuboidMesh(nx=1, ny=1, nz=1)

    sim = Sim(mesh, name='spin', driver='sllg')

    alpha = 0.1
    gamma = 2.21e5

    sim.set_options(dt=5e-15, gamma=gamma)

    sim.alpha = alpha
    sim.mu_s = 1.0

    sim.set_m((1, 0, 0))

    H0 = 1e5
    sim.add(Zeeman((0, 0, H0)))

    ts = np.linspace(0, 1e-10, 101)

    mx = []
    my = []
    mz = []
    real_ts = []
    for t in ts:
        sim.run_until(t)
        real_ts.append(sim.t)
        print(sim.t, abs(sim.spin_length()[0] - 1))
        mx.append(sim.spin[0])
        my.append(sim.spin[1])
        mz.append(sim.spin[2])

    mz = np.array(mz)

    a_mx, a_my, a_mz = single_spin(alpha, gamma, H0, ts)

    if do_plot:
        plot(real_ts, mx, my, mz, a_mx, a_my, a_mz, name='spin_sllg.pdf', title='integrating a spin')

    print(("Max Deviation = {0}".format(
        np.max(np.abs(mz - a_mz)))))

    assert np.max(np.abs(mz - a_mz)) < 1e-8

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def test_sim_single_spin_vode(do_plot=False):

    mesh = CuboidMesh(nx=1, ny=1, nz=1)

    sim = Sim(mesh, name='spin')

    alpha = 0.1
    gamma = 2.21e5
    sim.alpha = alpha
    sim.gamma = gamma
    sim.mu_s = 1.0

    sim.set_m((1, 0, 0))

    H0 = 1e5
    sim.add(Zeeman((0, 0, H0)))

    ts = np.linspace(0, 1e-9, 101)

    mx = []
    my = []
    mz = []
    real_ts = []
    for t in ts:
        sim.run_until(t)
        real_ts.append(sim.t)
        #print sim.t, abs(sim.spin_length()[0] - 1)
        mx.append(sim.spin[0])
        my.append(sim.spin[1])
        mz.append(sim.spin[2])

    mz = np.array(mz)
    a_mx, a_my, a_mz = single_spin(alpha, gamma, H0, ts)

    print sim.stat()

    if do_plot:
        plot(real_ts, mx, my, mz, a_mx, a_my, a_mz)

    print("Max Deviation = {0}".format(
        np.max(np.abs(mz - a_mz))))

    assert np.max(np.abs(mz - a_mz)) < 5e-7

# 需要导入模块: from fidimag.atomistic import Sim [as 别名]
# 或者: from fidimag.atomistic.Sim import run_until [as 别名]
def dynamic(mesh):

    sim = Sim(mesh, name='dyn_spin', driver='slonczewski')
    # sim.set_options(rtol=1e-10,atol=1e-14)
    sim.driver.gamma = 1.0
    sim.mu_s = 1.0

    sim.set_m((0.8,0,-1))

    Kx = Anisotropy(Ku=-0.05, axis=(0, 0, 1), name='Kz')
    sim.add(Kx)

    sim.p = (0,0,1)

    sim.u0 = 0.005
    sim.driver.alpha = 0.1

    ts = np.linspace(0, 1200, 401)
    for t in ts:
        sim.run_until(t)
        #sim.save_vtk()
        print t