#nmag.set_log_level('debug')
intensive_param_by_name = {"H_x": 0.1, "H_y": 0.0, "H_z": 0.0}
# very slightly pulling in x-direction
def test_anisotropy_energy(v): # direction is unit-normalized!
print "DDD anisotropy dir=", v
result = (1.0 * v[0] * v[0] + 2.0 * v[1] * v[1] + 3.5 * v[2] * v[2])
return result * 0.0
mat_Py = nmag.MagMaterial(
"Py",
Ms=SI(1e6, "A/m"),
J=SI(13.0e-12, "J/m"),
#Ms=1., #Matteo, very strange: if I use the SI units above,
#J=13., #then I get a wierd magsim-brain failure!
anisotropy_order=2,
anisotropy=test_anisotropy_energy)
sim = nmag.SimulationContext("sphere")
# sim.timestepper_tuning_params=[1e-6,1e-6,2,300] # These are the defaults...
sim.timestepper_tuning_params = [1e-6, 1e-6, 2, 300]
sim.defregion("Py", nm.ellipsoid([3.0, 3.0, 3.0]), mag_mat=mat_Py)
def initial_magnetization_0(coords, mag_type):
return [
0.8 * math.sin(coords[0] / 1.0) * 1e6,
import nmag2 as nmag, nmesh as nm, sys, math, time
import nfem
# import nfem.visual
import ocaml #need this as long as we use ocaml.probe_field
from nmag2.si_units import SI
#nmag.set_global_log_level('debug')
#nmag.set_log_level('debug')
intensive_param_by_name={"H_x":0.0,"H_y":0.0,"H_z":0.0}
# Not applying any external field.
mat_Py = nmag.MagMaterial("Py",
Ms=SI(1e6,"A/m"),
J=SI(13.0e-12,"J/m"),
)
# We afterwards hack the parameters of that material definition
# that actually enter the LLG:
print "LLG length control: ", mat_Py.su_llg_gamma
# THIS RETURNS: LLG length control: 1e-24
# That is completely bogus!
# BUGFIX REQUIRED!
mat_Py.su_llg_coeff1= -0.5*1.0 # M x H
mat_Py.su_llg_coeff2= -0.02*0.0 # M x (M x H) -- NOTE that the coefficient MUST be negative here.
# mat_Py.su_llg_gamma=2.0 # length control
mat_Py.su_llg_gamma=0.2 # length control
#produce more output for now
nmag.set_global_log_level('debug')
nmag.set_log_level('debug')
intensive_param_by_name={"H_x":0.0,"H_y":0.0,"H_z":0.0}
# very slightly pulling in x-direction
def test_anisotropy_energy(v): # direction is unit-normalized!
print "DDD anisotropy dir=",v
result=(1.0*v[0]*v[0]+2.0*v[1]*v[1]+3.5*v[2]*v[2])
return result*0.0
mat_Py = nmag.MagMaterial("Py",
Ms=SI(1e6,"A/m"),
exchange_coupling=SI(13.0e-12,"J/m"),
#Ms=1.,
#J=13.,
anisotropy_order=2,
anisotropy=test_anisotropy_energy
)
sim=nmag.SimulationContext("sphere")
# sim.timestepper_tuning_params=[1e-6,1e-6,2,300] # These are the defaults...
sim.timestepper_tuning_params=[1e-6,1e-6,4,300]
sim.set_magnetization([0.0,1.0,0.0])
# ^ just to show we can place set_magnetization() where we want...
sim.defregion("Py", nm.ellipsoid([3.0,3.0,3.0]), mag_mat=mat_Py)
def initial_magnetization(coords,mag_type):
#
# (C) 2006 Dr. Thomas Fischbacher
# Relaxation of the homogeneously magnetized sphere
import nmag2 as nmag, nmesh as nm, sys, math, time
import nfem
import nfem.visual
intensive_param_by_name = {"H_x": 0.1, "H_y": 0.0, "H_z": 0.0}
# very slightly pulling in x-direction
mat_Py = nmag.MagMaterial(
"Py",
Ms=1.0,
J=13.0, # A = exchange constant
alpha=0.5,
beta=0.2,
gamma=2.0,
)
sim = nmag.SimulationContext("sphere", )
sim.defregion("Py", nm.ellipsoid([3.0, 3.0, 3.0]), mag_mat=mat_Py)
def initial_magnetization(dof_name, coords):
direction = dof_name[1][0]
if direction == 2:
return 0.6
elif direction == 1:
return 0.8 * math.cos(coords[0] / 3.0)
import ocaml #need this as long as we use ocaml.probe_field
intensive_param_by_name = {"H_x": 0.2, "H_y": 0.0, "H_z": 0.0}
# very slightly pulling in x-direction
def test_anisotropy_energy(v): # direction is unit-normalized!
print "DDD anisotropy dir=", v
result = (1.0 * v[0] * v[0] + 2.0 * v[1] * v[1] + 3.5 * v[2] * v[2])
return result
mat_Py = nmag.MagMaterial("Py",
Ms=1.0,
J=13.0,
anisotropy_order=2,
anisotropy=test_anisotropy_energy)
mat_Fe = nmag.MagMaterial("Fe", Ms=SI(1.7e6, "A/m"), J=SI(2.07e-11, "J/m"))
sim = nmag.SimulationContext("sphere")
# sim.timestepper_tuning_params=[1e-6,1e-6,2,300] # These are the defaults...
sim.timestepper_tuning_params = [1e-6, 1e-6, 4, 300]
sim.set_magnetization([0.0, 1.0, 0.0])
# ^ just to show we can place set_magnetization() where we want...
sim.defregion("Py",
nmesh.ellipsoid([2.0, 2.0, 2.0],
import ocaml #need this as long as we use ocaml.probe_field
from nmag2.si_units import SI
time_init = time.time()
#produce more output for now
#nmag.set_global_log_level('debug')
#nmag.set_log_level('debug')
intensive_param_by_name = {"H_x": 0.1, "H_y": 0.0, "H_z": 0.0}
# very slightly pulling in x-direction
mat_Py = nmag.MagMaterial(
"Py",
Ms=SI(1e6, "A/m"),
exchange_coupling=SI(13.0e-12, "J/m"),
)
sim = nmag.SimulationContext("sphere")
# sim.timestepper_tuning_params=[1e-6,1e-6,2,300] # These are the defaults...
sim.timestepper_tuning_params = [1e-6, 1e-6, 2, 300]
sim.defregion("Py", nm.ellipsoid([3.0, 3.0, 3.0]), mag_mat=mat_Py)
def initial_magnetization(coords, mag_type):
return [
0.8 * math.sin(coords[0] / 1.0) * 1e6,
0.8 * math.cos(coords[0] / 1.0) * 1e6, 0.6 * 1e6