from __future__ import annotations
from abc import ABC, abstractmethod
from collections.abc import Iterable
from enum import IntEnum
from numbers import Real
import warnings
import typing # imported separately as py3.8 requires typing.Iterable
# also required to prevent typing.Union namespace overwriting Union
from typing import Optional, Sequence
import lxml.etree as ET
import numpy as np
import h5py
import openmc
import openmc.checkvalue as cv
from openmc.checkvalue import PathLike
from openmc.stats.multivariate import UnitSphere, Spatial
from openmc.stats.univariate import Univariate
from ._xml import get_text
from .mesh import MeshBase
[docs]class SourceBase(ABC):
"""Base class for external sources
Parameters
----------
strength : float
Strength of the source
Attributes
----------
type : {'independent', 'file', 'compiled'}
Indicator of source type.
strength : float
Strength of the source
"""
def __init__(self, strength=1.0):
self.strength = strength
@property
def strength(self):
return self._strength
@strength.setter
def strength(self, strength):
cv.check_type('source strength', strength, Real)
cv.check_greater_than('source strength', strength, 0.0, True)
self._strength = strength
[docs] @abstractmethod
def populate_xml_element(self, element):
"""Add necessary source information to an XML element
Returns
-------
element : lxml.etree._Element
XML element containing source data
"""
pass
[docs] def to_xml_element(self) -> ET.Element:
"""Return XML representation of the source
Returns
-------
element : xml.etree.ElementTree.Element
XML element containing source data
"""
element = ET.Element("source")
element.set("type", self.type)
element.set("strength", str(self.strength))
self.populate_xml_element(element)
return element
[docs] @classmethod
def from_xml_element(cls, elem: ET.Element, meshes=None) -> openmc.SourceBase:
"""Generate source from an XML element
Parameters
----------
elem : lxml.etree._Element
XML element
meshes : dict
Dictionary with mesh IDs as keys and openmc.MeshBase instances as
values
Returns
-------
openmc.SourceBase
Source generated from XML element
"""
source_type = get_text(elem, 'type')
if source_type is None:
# attempt to determine source type based on attributes
# for backward compatibility
if get_text(elem, 'file') is not None:
return FileSource.from_xml_element(elem)
elif get_text(elem, 'library') is not None:
return CompiledSource.from_xml_element(elem)
else:
return IndependentSource.from_xml_element(elem)
else:
if source_type == 'independent':
return IndependentSource.from_xml_element(elem, meshes)
elif source_type == 'compiled':
return CompiledSource.from_xml_element(elem)
elif source_type == 'file':
return FileSource.from_xml_element(elem)
else:
raise ValueError(f'Source type {source_type} is not recognized')
[docs]class IndependentSource(SourceBase):
"""Distribution of phase space coordinates for source sites.
.. versionadded:: 0.14.0
Parameters
----------
space : openmc.stats.Spatial
Spatial distribution of source sites
angle : openmc.stats.UnitSphere
Angular distribution of source sites
energy : openmc.stats.Univariate
Energy distribution of source sites
time : openmc.stats.Univariate
time distribution of source sites
strength : float
Strength of the source
particle : {'neutron', 'photon'}
Source particle type
domains : iterable of openmc.Cell, openmc.Material, or openmc.Universe
Domains to reject based on, i.e., if a sampled spatial location is not
within one of these domains, it will be rejected.
Attributes
----------
space : openmc.stats.Spatial or None
Spatial distribution of source sites
angle : openmc.stats.UnitSphere or None
Angular distribution of source sites
energy : openmc.stats.Univariate or None
Energy distribution of source sites
time : openmc.stats.Univariate or None
time distribution of source sites
strength : float
Strength of the source
type : str
Indicator of source type: 'independent'
.. versionadded:: 0.14.0
particle : {'neutron', 'photon'}
Source particle type
ids : Iterable of int
IDs of domains to use for rejection
domain_type : {'cell', 'material', 'universe'}
Type of domain to use for rejection
"""
def __init__(
self,
space: Optional[openmc.stats.Spatial] = None,
angle: Optional[openmc.stats.UnitSphere] = None,
energy: Optional[openmc.stats.Univariate] = None,
time: Optional[openmc.stats.Univariate] = None,
strength: float = 1.0,
particle: str = 'neutron',
domains: Optional[Sequence[typing.Union[openmc.Cell, openmc.Material, openmc.Universe]]] = None
):
super().__init__(strength)
self._space = None
self._angle = None
self._energy = None
self._time = None
if space is not None:
self.space = space
if angle is not None:
self.angle = angle
if energy is not None:
self.energy = energy
if time is not None:
self.time = time
self.strength = strength
self.particle = particle
self._domain_ids = []
self._domain_type = None
if domains is not None:
if isinstance(domains[0], openmc.Cell):
self.domain_type = 'cell'
elif isinstance(domains[0], openmc.Material):
self.domain_type = 'material'
elif isinstance(domains[0], openmc.Universe):
self.domain_type = 'universe'
self.domain_ids = [d.id for d in domains]
@property
def type(self) -> str:
return 'independent'
def __getattr__(self, name):
cls_names = {'file': 'FileSource', 'library': 'CompiledSource',
'parameters': 'CompiledSource'}
if name in cls_names:
raise AttributeError(
f'The "{name}" attribute has been deprecated on the '
f'IndependentSource class. Please use the {cls_names[name]} class.')
else:
super().__getattribute__(name)
def __setattr__(self, name, value):
if name in ('file', 'library', 'parameters'):
# Ensure proper AttributeError is thrown
getattr(self, name)
else:
super().__setattr__(name, value)
@property
def space(self):
return self._space
@space.setter
def space(self, space):
cv.check_type('spatial distribution', space, Spatial)
self._space = space
@property
def angle(self):
return self._angle
@angle.setter
def angle(self, angle):
cv.check_type('angular distribution', angle, UnitSphere)
self._angle = angle
@property
def energy(self):
return self._energy
@energy.setter
def energy(self, energy):
cv.check_type('energy distribution', energy, Univariate)
self._energy = energy
@property
def time(self):
return self._time
@time.setter
def time(self, time):
cv.check_type('time distribution', time, Univariate)
self._time = time
@property
def particle(self):
return self._particle
@particle.setter
def particle(self, particle):
cv.check_value('source particle', particle, ['neutron', 'photon'])
self._particle = particle
@property
def domain_ids(self):
return self._domain_ids
@domain_ids.setter
def domain_ids(self, ids):
cv.check_type('domain IDs', ids, Iterable, Real)
self._domain_ids = ids
@property
def domain_type(self):
return self._domain_type
@domain_type.setter
def domain_type(self, domain_type):
cv.check_value('domain type', domain_type, ('cell', 'material', 'universe'))
self._domain_type = domain_type
[docs] def populate_xml_element(self, element):
"""Add necessary source information to an XML element
Returns
-------
element : lxml.etree._Element
XML element containing source data
"""
super().populate_xml_element(element)
element.set("particle", self.particle)
if self.space is not None:
element.append(self.space.to_xml_element())
if self.angle is not None:
element.append(self.angle.to_xml_element())
if self.energy is not None:
element.append(self.energy.to_xml_element('energy'))
if self.time is not None:
element.append(self.time.to_xml_element('time'))
if self.domain_ids:
dt_elem = ET.SubElement(element, "domain_type")
dt_elem.text = self.domain_type
id_elem = ET.SubElement(element, "domain_ids")
id_elem.text = ' '.join(str(uid) for uid in self.domain_ids)
[docs] @classmethod
def from_xml_element(cls, elem: ET.Element, meshes=None) -> 'openmc.SourceBase':
"""Generate source from an XML element
Parameters
----------
elem : lxml.etree._Element
XML element
meshes : dict
Dictionary with mesh IDs as keys and openmc.MeshBase instaces as
values
Returns
-------
openmc.Source
Source generated from XML element
"""
domain_type = get_text(elem, "domain_type")
if domain_type is not None:
domain_ids = [int(x) for x in get_text(elem, "domain_ids").split()]
# Instantiate some throw-away domains that are used by the
# constructor to assign IDs
with warnings.catch_warnings():
warnings.simplefilter('ignore', openmc.IDWarning)
if domain_type == 'cell':
domains = [openmc.Cell(uid) for uid in domain_ids]
elif domain_type == 'material':
domains = [openmc.Material(uid) for uid in domain_ids]
elif domain_type == 'universe':
domains = [openmc.Universe(uid) for uid in domain_ids]
else:
domains = None
source = cls(domains=domains)
strength = get_text(elem, 'strength')
if strength is not None:
source.strength = float(strength)
particle = get_text(elem, 'particle')
if particle is not None:
source.particle = particle
filename = get_text(elem, 'file')
if filename is not None:
source.file = filename
space = elem.find('space')
if space is not None:
source.space = Spatial.from_xml_element(space, meshes)
angle = elem.find('angle')
if angle is not None:
source.angle = UnitSphere.from_xml_element(angle)
energy = elem.find('energy')
if energy is not None:
source.energy = Univariate.from_xml_element(energy)
time = elem.find('time')
if time is not None:
source.time = Univariate.from_xml_element(time)
return source
def Source(*args, **kwargs):
"""
A function for backward compatibility of sources. Will be removed in the
future. Please update to IndependentSource.
"""
warnings.warn("This class is deprecated in favor of 'IndependentSource'", FutureWarning)
return openmc.IndependentSource(*args, **kwargs)
[docs]class CompiledSource(SourceBase):
"""A source based on a compiled shared library
.. versionadded:: 0.14.0
Parameters
----------
library : str or None
Path to a compiled shared library
parameters : str
Parameters to be provided to the compiled shared library function
strength : float
Strength of the source
Attributes
----------
library : str or None
Path to a compiled shared library
parameters : str
Parameters to be provided to the compiled shared library function
strength : float
Strength of the source
type : str
Indicator of source type: 'compiled'
"""
def __init__(self, library: Optional[str] = None, parameters: Optional[str] = None, strength=1.0) -> None:
super().__init__(strength=strength)
self._library = None
if library is not None:
self.library = library
self._parameters = None
if parameters is not None:
self.parameters = parameters
@property
def type(self) -> str:
return "compiled"
@property
def library(self) -> str:
return self._library
@library.setter
def library(self, library_name):
cv.check_type('library', library_name, str)
self._library = library_name
@property
def parameters(self) -> str:
return self._parameters
@parameters.setter
def parameters(self, parameters_path):
cv.check_type('parameters', parameters_path, str)
self._parameters = parameters_path
[docs] def populate_xml_element(self, element):
"""Add necessary compiled source information to an XML element
Returns
-------
element : lxml.etree._Element
XML element containing source data
"""
super().populate_xml_element(element)
element.set("library", self.library)
if self.parameters is not None:
element.set("parameters", self.parameters)
[docs] @classmethod
def from_xml_element(cls, elem: ET.Element, meshes=None) -> openmc.CompiledSource:
"""Generate a compiled source from an XML element
Parameters
----------
elem : lxml.etree._Element
XML element
meshes : dict
Dictionary with mesh IDs as keys and openmc.MeshBase instances as
values
Returns
-------
openmc.CompiledSource
Source generated from XML element
"""
library = get_text(elem, 'library')
source = cls(library)
strength = get_text(elem, 'strength')
if strength is not None:
source.strength = float(strength)
parameters = get_text(elem, 'parameters')
if parameters is not None:
source.parameters = parameters
return source
[docs]class FileSource(SourceBase):
"""A source based on particles stored in a file
.. versionadded:: 0.14.0
Parameters
----------
path : str or pathlib.Path
Path to the source file from which sites should be sampled
strength : float
Strength of the source (default is 1.0)
Attributes
----------
path : Pathlike
Source file from which sites should be sampled
strength : float
Strength of the source
type : str
Indicator of source type: 'file'
"""
def __init__(self, path: Optional[PathLike] = None, strength=1.0) -> None:
super().__init__(strength=strength)
self._path = None
if path is not None:
self.path = path
@property
def type(self) -> str:
return "file"
@property
def path(self) -> PathLike:
return self._path
@path.setter
def path(self, p: PathLike):
cv.check_type('source file', p, str)
self._path = p
[docs] def populate_xml_element(self, element):
"""Add necessary file source information to an XML element
Returns
-------
element : lxml.etree._Element
XML element containing source data
"""
super().populate_xml_element(element)
if self.path is not None:
element.set("file", self.path)
[docs] @classmethod
def from_xml_element(cls, elem: ET.Element) -> openmc.FileSource:
"""Generate file source from an XML element
Parameters
----------
elem : lxml.etree._Element
XML element
meshes : dict
Dictionary with mesh IDs as keys and openmc.MeshBase instances as
values
Returns
-------
openmc.FileSource
Source generated from XML element
"""
filename = get_text(elem, 'file')
source = cls(filename)
strength = get_text(elem, 'strength')
if strength is not None:
source.strength = float(strength)
return source
class ParticleType(IntEnum):
"""
IntEnum class representing a particle type. Type
values mirror those found in the C++ class.
"""
NEUTRON = 0
PHOTON = 1
ELECTRON = 2
POSITRON = 3
@classmethod
def from_string(cls, value: str):
"""
Constructs a ParticleType instance from a string.
Parameters
----------
value : str
The string representation of the particle type.
Returns
-------
The corresponding ParticleType instance.
"""
try:
return cls[value.upper()]
except KeyError:
raise ValueError(f"Invalid string for creation of {cls.__name__}: {value}")
def __repr__(self) -> str:
"""
Returns a string representation of the ParticleType instance.
Returns:
str: The lowercase name of the ParticleType instance.
"""
return self.name.lower()
# needed for < Python 3.11
def __str__(self) -> str:
return self.__repr__()
# needed for <= 3.7, IntEnum will use the mixed-in type's `__format__` method otherwise
# this forces it to default to the standard object format, relying on __str__ under the hood
def __format__(self, spec):
return object.__format__(self, spec)
[docs]class SourceParticle:
"""Source particle
This class can be used to create source particles that can be written to a
file and used by OpenMC
Parameters
----------
r : iterable of float
Position of particle in Cartesian coordinates
u : iterable of float
Directional cosines
E : float
Energy of particle in [eV]
time : float
Time of particle in [s]
wgt : float
Weight of the particle
delayed_group : int
Delayed group particle was created in (neutrons only)
surf_id : int
Surface ID where particle is at, if any.
particle : ParticleType
Type of the particle
"""
def __init__(
self,
r: typing.Iterable[float] = (0., 0., 0.),
u: typing.Iterable[float] = (0., 0., 1.),
E: float = 1.0e6,
time: float = 0.0,
wgt: float = 1.0,
delayed_group: int = 0,
surf_id: int = 0,
particle: ParticleType = ParticleType.NEUTRON
):
self.r = tuple(r)
self.u = tuple(u)
self.E = float(E)
self.time = float(time)
self.wgt = float(wgt)
self.delayed_group = delayed_group
self.surf_id = surf_id
self.particle = particle
def __repr__(self):
name = self.particle.name.lower()
return f'<SourceParticle: {name} at E={self.E:.6e} eV>'
[docs] def to_tuple(self) -> tuple:
"""Return source particle attributes as a tuple
Returns
-------
tuple
Source particle attributes
"""
return (self.r, self.u, self.E, self.time, self.wgt,
self.delayed_group, self.surf_id, self.particle.value)
[docs]def write_source_file(
source_particles: typing.Iterable[SourceParticle],
filename: PathLike, **kwargs
):
"""Write a source file using a collection of source particles
Parameters
----------
source_particles : iterable of SourceParticle
Source particles to write to file
filename : str or path-like
Path to source file to write
**kwargs
Keyword arguments to pass to :class:`h5py.File`
See Also
--------
openmc.SourceParticle
"""
# Create compound datatype for source particles
pos_dtype = np.dtype([('x', '<f8'), ('y', '<f8'), ('z', '<f8')])
source_dtype = np.dtype([
('r', pos_dtype),
('u', pos_dtype),
('E', '<f8'),
('time', '<f8'),
('wgt', '<f8'),
('delayed_group', '<i4'),
('surf_id', '<i4'),
('particle', '<i4'),
])
# Create array of source particles
cv.check_iterable_type("source particles", source_particles, SourceParticle)
arr = np.array([s.to_tuple() for s in source_particles], dtype=source_dtype)
# Write array to file
kwargs.setdefault('mode', 'w')
with h5py.File(filename, **kwargs) as fh:
fh.attrs['filetype'] = np.string_("source")
fh.create_dataset('source_bank', data=arr, dtype=source_dtype)