Python Sim.do_procession方法代码示例

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def test_dw_dmi(mesh=mesh, do_plot=False):

    Ms = 8.0e5
    sim = Sim(mesh, name='relax')

    sim.set_m(m_init_dw)

    sim.set_tols(rtol=1e-8, atol=1e-12)
    sim.Ms = Ms
    sim.alpha = 0.5
    sim.do_procession = False

    A = 1.3e-11
    D = 4e-4
    Kx = 8e4
    Kp = -6e5

    sim.add(UniformExchange(A))
    sim.add(DMI(D))
    sim.add(UniaxialAnisotropy(Kx, axis=[1, 0, 0], name='Kx'))

    sim.relax(stopping_dmdt=0.01)

    xs = np.array([p[0] for p in mesh.coordinates])
    mx, my, mz = analytical(xs, A=A, D=D, K=Kx)
    mxyz = sim.spin.copy()
    mxyz = mxyz.reshape(-1, 3)

    assert max(abs(mxyz[:, 0] - mx)) < 0.002
    assert max(abs(mxyz[:, 1] - my)) < 0.002
    assert max(abs(mxyz[:, 2] - mz)) < 0.0006

    if do_plot:

        save_plot(mxyz, mx, my, mz)

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def relax_system(mesh):

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

    sim.set_tols(rtol=1e-6, atol=1e-6)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

    sim.set_m(init_m)
    #sim.set_m((0,0.1,1))
    #sim.set_m(np.load('m0.npy'))

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    dmi = DMI(D=1.3e-3)
    sim.add(dmi)

    anis = UniaxialAnisotropy(-3.25e4, axis=(0, 0, 1))
    sim.add(anis)

    zeeman = Zeeman((0, 0, 6.014576e4))
    sim.add(zeeman, save_field=True)

    sim.relax(dt=1e-13, stopping_dmdt=0.5, max_steps=5000,
              save_m_steps=None, save_vtk_steps=50)

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

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def relax_system(mesh):

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

    sim.set_tols(rtol=1e-10, atol=1e-14)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

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

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    dmi = DMI(D=1e-3)
    sim.add(dmi)

    zeeman = Zeeman((0, 0, 2e4))
    sim.add(zeeman, save_field=True)

    sim.relax(dt=1e-13, stopping_dmdt=0.01, max_steps=5000,
              save_m_steps=None, save_vtk_steps=50)

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

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def compute_field():

    mesh = CuboidMesh(nx=1, ny=1, nz=1, dx=2.0, dy=2.0, dz=2.0, unit_length=1e-9, periodicity=(True, True, False))

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

    sim.set_tols(rtol=1e-10, atol=1e-14)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

    sim.set_m((0,0,1))
    # sim.set_m(np.load('m0.npy'))

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    demag = Demag(pbc_2d=True)
    sim.add(demag)
    field=demag.compute_field()
    print field

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

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def relax_system(mesh):

    # Only relaxation
    sim = Sim(mesh, name='relax')

    # Simulation parameters
    sim.set_tols(rtol=1e-8, atol=1e-10)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

    # The initial state passed as a function
    sim.set_m(init_m)
    # sim.set_m(np.load('m0.npy'))

    # Energies
    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    anis = UniaxialAnisotropy(5e4)
    sim.add(anis)

    # dmi = DMI(D=8e-4)
    # sim.add(dmi)

    # Start relaxation and save the state in m0.npy
    sim.relax(dt=1e-14, stopping_dmdt=0.00001, max_steps=5000,
              save_m_steps=None, save_vtk_steps=None)

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

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def relax_system_only_exchange(mesh):

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

    sim.set_tols(rtol=1e-6, atol=1e-6)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

    sim.set_m(init_m_BP)

    A = 1.3e-11
    exch = UniformExchange(A=A)
    sim.add(exch)

    sim.relax(dt=1e-13, stopping_dmdt=0.5, max_steps=5000,
              save_m_steps=None, save_vtk_steps=50)

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

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def test_compute_field():
    """In an infinite film, we expect the demag tensor to be (0, 0, -1), and thus the
    magnetisation, if aligned in 0, 0, 1 direction, to create a demag field pointing
    with equal strength in the opposite direction.
    """

    mesh = CuboidMesh(nx=1, ny=1, nz=1, dx=2.0, dy=2.0, dz=2.0, 
                      unit_length=1e-9, periodicity=(True, True, False))

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

    sim.set_tols(rtol=1e-10, atol=1e-14)
    sim.alpha = 0.5
    sim.gamma = 2.211e5
    sim.Ms = 8.6e5
    sim.do_procession = False

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

    demag = Demag(pbc_2d=True)
    sim.add(demag)
    field=demag.compute_field()
    print(1 + field[2] / 8.6e5) 
    assert abs(1 + field[2] / 8.6e5) < 1e-10

# 需要导入模块: from fidimag.micro import Sim [as 别名]
# 或者: from fidimag.micro.Sim import do_procession [as 别名]
def init_m(pos):

    x, y = pos[0] - radius, pos[1] - radius

    if x ** 2 + y ** 2 < radius ** 2:
        return (0, 0, -1)
    else:
        return (0, 0, 1)

# Prepare simulation
# We define the cylinder with the Magnetisation function
sim = Sim(mesh, name='skyrmion_down')
sim.Ms = cylinder

# To get a faster relaxation, we tune the LLG equation parameters
sim.do_procession = False
sim.alpha = 0.5

# Initial magnetisation:
sim.set_m(init_m)

# Energies:

# Exchange
sim.add(UniformExchange(A=A))

# Bulk DMI
sim.add(DMI(D=D))

# Relax the system
sim.relax(dt=1e-12, stopping_dmdt=0.0001, max_steps=5000,