from collections.abc import Iterable
from io import StringIO
from numbers import Real
import sys
import numpy as np
import openmc.checkvalue as cv
from openmc.mixin import EqualityMixin
from .angle_energy import AngleEnergy
from .function import Tabulated1D, Polynomial, Function1D
[docs]class Product(EqualityMixin):
"""Secondary particle emitted in a nuclear reaction
Parameters
----------
particle : str, optional
What particle the reaction product is. Defaults to 'neutron'.
Attributes
----------
applicability : Iterable of openmc.data.Tabulated1D
Probability of sampling a given distribution for this product.
decay_rate : float
Decay rate in inverse seconds
distribution : Iterable of openmc.data.AngleEnergy
Distributions of energy and angle of product.
emission_mode : {'prompt', 'delayed', 'total'}
Indicate whether the particle is emitted immediately or whether it
results from the decay of reaction product (e.g., neutron emitted from a
delayed neutron precursor). A special value of 'total' is used when the
yield represents particles from prompt and delayed sources.
particle : str
What particle the reaction product is.
yield_ : openmc.data.Function1D
Yield of secondary particle in the reaction.
"""
def __init__(self, particle='neutron'):
self.particle = particle
self.decay_rate = 0.0
self.emission_mode = 'prompt'
self.distribution = []
self.applicability = []
self.yield_ = Polynomial((1,)) # 0-order polynomial i.e. a constant
def __repr__(self):
if isinstance(self.yield_, Real):
return "<Product: {}, emission={}, yield={}>".format(
self.particle, self.emission_mode, self.yield_)
elif isinstance(self.yield_, Tabulated1D):
if np.all(self.yield_.y == self.yield_.y[0]):
return "<Product: {}, emission={}, yield={}>".format(
self.particle, self.emission_mode, self.yield_.y[0])
else:
return "<Product: {}, emission={}, yield=tabulated>".format(
self.particle, self.emission_mode)
else:
return "<Product: {}, emission={}, yield=polynomial>".format(
self.particle, self.emission_mode)
@property
def applicability(self):
return self._applicability
@property
def decay_rate(self):
return self._decay_rate
@property
def distribution(self):
return self._distribution
@property
def emission_mode(self):
return self._emission_mode
@property
def particle(self):
return self._particle
@property
def yield_(self):
return self._yield
@applicability.setter
def applicability(self, applicability):
cv.check_type('product distribution applicability', applicability,
Iterable, Tabulated1D)
self._applicability = applicability
@decay_rate.setter
def decay_rate(self, decay_rate):
cv.check_type('product decay rate', decay_rate, Real)
cv.check_greater_than('product decay rate', decay_rate, 0.0, True)
self._decay_rate = decay_rate
@distribution.setter
def distribution(self, distribution):
cv.check_type('product angle-energy distribution', distribution,
Iterable, AngleEnergy)
self._distribution = distribution
@emission_mode.setter
def emission_mode(self, emission_mode):
cv.check_value('product emission mode', emission_mode,
('prompt', 'delayed', 'total'))
self._emission_mode = emission_mode
@particle.setter
def particle(self, particle):
cv.check_type('product particle type', particle, str)
self._particle = particle
@yield_.setter
def yield_(self, yield_):
cv.check_type('product yield', yield_, Function1D)
self._yield = yield_
[docs] def to_hdf5(self, group):
"""Write product to an HDF5 group
Parameters
----------
group : h5py.Group
HDF5 group to write to
"""
group.attrs['particle'] = np.string_(self.particle)
group.attrs['emission_mode'] = np.string_(self.emission_mode)
if self.decay_rate > 0.0:
group.attrs['decay_rate'] = self.decay_rate
# Write yield
self.yield_.to_hdf5(group, 'yield')
# Write applicability/distribution
group.attrs['n_distribution'] = len(self.distribution)
for i, d in enumerate(self.distribution):
dgroup = group.create_group('distribution_{}'.format(i))
if self.applicability:
self.applicability[i].to_hdf5(dgroup, 'applicability')
d.to_hdf5(dgroup)
[docs] @classmethod
def from_hdf5(cls, group):
"""Generate reaction product from HDF5 data
Parameters
----------
group : h5py.Group
HDF5 group to read from
Returns
-------
openmc.data.Product
Reaction product
"""
particle = group.attrs['particle'].decode()
p = cls(particle)
p.emission_mode = group.attrs['emission_mode'].decode()
if 'decay_rate' in group.attrs:
p.decay_rate = group.attrs['decay_rate']
# Read yield
p.yield_ = Function1D.from_hdf5(group['yield'])
# Read applicability/distribution
n_distribution = group.attrs['n_distribution']
distribution = []
applicability = []
for i in range(n_distribution):
dgroup = group['distribution_{}'.format(i)]
if 'applicability' in dgroup:
applicability.append(Tabulated1D.from_hdf5(
dgroup['applicability']))
distribution.append(AngleEnergy.from_hdf5(dgroup))
p.distribution = distribution
p.applicability = applicability
return p