from typing import Optional
from typing import Union
import numpy as np
from easyscience import global_object
from easyscience.Constraints import FunctionalConstraint
from easyscience.Objects.new_variable import Parameter
from easyreflectometry.special.calculations import density_to_sld
from easyreflectometry.special.calculations import molecular_weight
from easyreflectometry.special.calculations import neutron_scattering_length
from easyreflectometry.utils import get_as_parameter
from .material import DEFAULTS as MATERIAL_DEFAULTS
from .material import Material
DEFAULTS = {
'chemical_structure': 'Si',
'density': {
'description': 'The mass density of the material.',
'url': 'https://en.wikipedia.org/wiki/Density',
'value': 2.33,
'unit': 'gram / centimeter ** 3',
'min': 0,
'max': np.Inf,
'fixed': True,
},
'molecular_weight': {
'description': 'The molecular weight of a material.',
'url': 'https://en.wikipedia.org/wiki/Molecular_mass',
'value': 28.02,
'unit': 'g / mole',
'min': -np.Inf,
'max': np.Inf,
'fixed': True,
},
}
DEFAULTS.update(MATERIAL_DEFAULTS)
[docs]
class MaterialDensity(Material):
# Added in __init__
scattering_length_real: Parameter
scattering_length_imag: Parameter
molecular_weight: Parameter
density: Parameter
[docs]
def __init__(
self,
chemical_structure: Union[str, None] = None,
density: Union[Parameter, float, None] = None,
name: str = 'EasyMaterialDensity',
unique_name: Optional[str] = None,
interface=None,
):
"""Constructor.
:param chemical_structure: Chemical formula for the material.
:param density: Mass density for the material.
:param name: Identifier, defaults to `EasyMaterialDensity`.
:param interface: Interface object, defaults to `None`.
"""
if unique_name is None:
unique_name = global_object.generate_unique_name(self.__class__.__name__)
if chemical_structure is None:
chemical_structure = DEFAULTS['chemical_structure']
density = get_as_parameter(
name='density',
value=density,
default_dict=DEFAULTS,
unique_name_prefix=f'{unique_name}_Density',
)
scattering_length = neutron_scattering_length(chemical_structure)
mw = get_as_parameter(
name='molecular_weight',
value=molecular_weight(chemical_structure),
default_dict=DEFAULTS,
unique_name_prefix=f'{unique_name}_Mw',
)
scattering_length_real = get_as_parameter(
name='scattering_length_real',
value=scattering_length.real,
default_dict=DEFAULTS['sld'],
unique_name_prefix=f'{unique_name}_ScatteringLengthReal',
)
scattering_length_imag = get_as_parameter(
name='scattering_length_imag',
value=scattering_length.imag,
default_dict=DEFAULTS['isld'],
unique_name_prefix=f'{unique_name}_ScatteringLengthImag',
)
sld = get_as_parameter(
name='sld',
value=density_to_sld(scattering_length_real.value, mw.value, density.value),
default_dict=DEFAULTS,
unique_name_prefix=f'{unique_name}_Sld',
)
isld = get_as_parameter(
name='isld',
value=density_to_sld(scattering_length_imag.value, mw.value, density.value),
default_dict=DEFAULTS,
unique_name_prefix=f'{unique_name}_Isld',
)
constraint = FunctionalConstraint(sld, density_to_sld, [scattering_length_real, mw, density])
scattering_length_real.user_constraints['sld'] = constraint
mw.user_constraints['sld'] = constraint
density.user_constraints['sld'] = constraint
iconstraint = FunctionalConstraint(isld, density_to_sld, [scattering_length_imag, mw, density])
scattering_length_imag.user_constraints['isld'] = iconstraint
mw.user_constraints['isld'] = iconstraint
density.user_constraints['isld'] = iconstraint
super().__init__(sld, isld, name=name, interface=interface)
self._add_component('scattering_length_real', scattering_length_real)
self._add_component('scattering_length_imag', scattering_length_imag)
self._add_component('molecular_weight', mw)
self._add_component('density', density)
self._chemical_structure = chemical_structure
self.interface = interface
@property
def chemical_structure(self) -> str:
"""Get the chemical structure string."""
return self._chemical_structure
@chemical_structure.setter
def chemical_structure(self, structure_string: str) -> None:
"""Set the chemical structure string.
:param structure_string: String that defines the chemical structure.
"""
self._chemical_structure = structure_string
scattering_length = neutron_scattering_length(structure_string)
self.scattering_length_real.value = scattering_length.real
self.scattering_length_imag.value = scattering_length.imag
@property
def _dict_repr(self) -> dict[str, str]:
"""Dictionary representation of the instance."""
mat_dict = super()._dict_repr
mat_dict['chemical_structure'] = self._chemical_structure
mat_dict['density'] = f'{self.density.value:.2e} {self.density.unit}'
return mat_dict
[docs]
def as_dict(self, skip: list = []) -> dict[str, str]:
"""Produces a cleaned dict using a custom as_dict method to skip necessary things.
The resulting dict matches the parameters in __init__
:param skip: List of keys to skip, defaults to `None`.
"""
this_dict = super().as_dict(skip=skip)
# From Material
del this_dict['sld']
del this_dict['isld']
# Determined in __init__
del this_dict['scattering_length_real']
del this_dict['scattering_length_imag']
del this_dict['molecular_weight']
return this_dict
