def initialize(self, system):
self.system = system
self.Ms = Field(system.mesh)
self.Ms.fill(0.0)
self.alpha = Field(system.mesh)
self.alpha.fill(0.0)
self.__valid_factors = False
# Find other active modules
self.field_terms = []
self.field_energies = []
self.llge_terms = []
for mod in system.modules:
prop = mod.properties()
if 'EFFECTIVE_FIELD_TERM' in prop.keys():
self.field_terms.append(prop['EFFECTIVE_FIELD_TERM'])
if 'EFFECTIVE_FIELD_ENERGY' in prop.keys():
self.field_energies.append(prop['EFFECTIVE_FIELD_ENERGY'])
if 'LLGE_TERM' in prop.keys():
self.llge_terms.append(prop['LLGE_TERM'])
logger.info("LandauLifshitzGilbert module configuration:")
logger.info(" - H_tot = %s", " + ".join(self.field_terms) or "0")
logger.info(" - E_tot = %s", " + ".join(self.field_energies) or "0")
logger.info(" - dM/dt = %s",
" + ".join(["LLGE(M, H_tot)"] + self.llge_terms) or "0")
if not self.__do_precess:
logger.info(" - Precession term is disabled")
def __initFactors(self):
self.__f1 = f1 = Field(self.system.mesh) # precession factors of llge
self.__f2 = f2 = Field(self.system.mesh) # damping factors of llge
alpha, Ms = self.alpha, self.Ms
# Prepare factors
for x, y, z in self.system.mesh.iterateCellIndices():
alpha_i, Ms_i = alpha.get(x, y, z), Ms.get(x, y, z)
if Ms_i != 0.0:
gamma_prime = GYROMAGNETIC_RATIO / (1.0 + alpha_i**2)
f1_i = -gamma_prime
f2_i = -alpha_i * gamma_prime / Ms_i
else:
f1_i, f2_i = 0.0, 0.0
f1.set(x, y, z, f1_i)
f2.set(x, y, z, f2_i)
# If precession is disabled, blank f1.
if not self.__do_precess:
f1.fill(0.0)
# Done.
self.__valid_factors = True
def initialize(self, system):
self.system = system
self.k_uniaxial = Field(self.system.mesh)
self.k_uniaxial.fill(0.0)
self.k_cubic = Field(self.system.mesh)
self.k_cubic.fill(0.0)
self.axis1 = VectorField(self.system.mesh)
self.axis1.fill((0.0, 0.0, 0.0))
self.axis2 = VectorField(self.system.mesh)
self.axis2.fill((0.0, 0.0, 0.0))
def __update_field(self, state):
# Get value of homogeneous field
if hasattr(state, self.__value_id):
value = getattr(state, self.__value_id)
else:
if not self.__default_value:
raise ValueError(
"HomogeneousField: Can't initialize field '%s' because no initial value is given!"
% self.__var_id)
value = self.__default_value
# Create field (Field or VectorField) from value
try:
if isinstance(value, numbers.Number):
value = float(value)
field = Field(self.__mesh)
field.fill(value)
elif hasattr(value, "__iter__") and len(value) == 3:
value = tuple(map(float, value))
field = VectorField(self.__mesh)
field.fill(value)
else:
raise ValueError
except ValueError:
raise ValueError(
"HomogeneousField: Expected scalar value or 3-tuple of scalar values for the 'value' (second) parameter"
)
# Store value and field in state
setattr(state, self.__value_id, value)
setattr(state, self.__field_id, field)
return field
def initialize(self, system):
self.system = system
self.A = Field(self.system.mesh)
self.A.fill(0.0)
self.__peri_x = system.mesh.periodic_bc[0].find("x") != -1
self.__peri_y = system.mesh.periodic_bc[0].find("y") != -1
self.__peri_z = system.mesh.periodic_bc[0].find("z") != -1
def calculate_minimizer_dM_minimize_BB(self, state):
# TODO other LLG terms?
if not self.__valid_factors: self.__initFactors()
if hasattr(state.cache, "minimizer_dM_minimize_BB"):
return state.cache.minimizer_dM_minimize_BB
result = state.cache.minimizer_dM_minimize_BB = VectorField(
self.system.mesh)
# Get effective field
H_tot = self.calculate_H_tot(state)
# TODO do this in every step?
zero = Field(self.system.mesh)
zero.fill(0.0)
# changed; set llge coefficient to 1.0 for minimization
factor = Field(self.system.mesh)
factor.fill(1.)
magneto.llge(zero, factor, state.M, H_tot, result)
return result
def set_param(self, id, val):
if id == self.__var_id:
if isinstance(val, numbers.Number):
fld = Field(self.system.mesh)
fld.fill(val)
elif hasattr(val, "__iter__") and len(val) == 3:
val = tuple(map(float, val))
field = VectorField(self.system.mesh)
field.fill(val)
elif isinstance(val, Field):
fld = Field(self.system.mesh)
fld.assign(val)
elif isinstance(val, VectorField):
fld = VectorField(self.system.mesh)
fld.assign(val)
else:
raise ValueError
self.__field = fld
else:
raise ValueError("%s: Don't know how to update %s." %
(self.name(), id))
def calculate_minimizer_dM(self, state):
# TODO other LLG terms?
if not self.__valid_factors: self.__initFactors()
if hasattr(state.cache, "minimizer_dM"):
return state.cache.minimizer_dM
result = state.cache.minimizer_dM = VectorField(self.system.mesh)
# Get effective field
H_tot = self.calculate_H_tot(state)
# TODO do this in every step?
zero = Field(self.system.mesh)
zero.fill(0.0)
magneto.llge(zero, self.__f2, state.M, H_tot, result)
return result
def initialize(self, system):
self.system = system
self.P = Field(self.system.mesh)
self.P.fill(0.0)
self.xi = Field(self.system.mesh)
self.xi.fill(0.0)
def initialize(self, system):
self.system = system
self.A = Field(self.system.mesh)
self.A.fill(0.0)