armi.nuclearDataIO.xsLibraries module

Cross section library objects.

Cross section libraries, currently, contain neutron and/or gamma cross sections, but are not necessarily intended to be only neutron and gamma data.

armi.nuclearDataIO.xsLibraries.compare(lib1, lib2)

Compare two XSLibraries, and return True if equal, or False if not.

armi.nuclearDataIO.xsLibraries._checkLabels(llib1, llib2)

armi.nuclearDataIO.xsLibraries.compareXSLibraryAttribute(lib1, lib2, attributeName, tolerance=0.0)

Compare the values of an attribute in two libraries.

armi.nuclearDataIO.xsLibraries.compareLibraryNeutronEnergies(lib1, lib2, tolerance=0.0)

Compare the neutron velocities and energy upper bounds for two libraries.

armi.nuclearDataIO.xsLibraries.getSuffixFromNuclideLabel(nucLabel)

Return the xs suffix for the nuclide label.

Parameters

nucLabel (str) – A string representing the nuclide and xs suffix, eg, “U235AA”

Returns

suffix – The suffix of this string

Return type

str

armi.nuclearDataIO.xsLibraries.getISOTXSLibrariesToMerge(xsLibrarySuffix, xsLibFileNames)

Find ISOTXS libraries out of a list that should be merged based on the provided xsLibrarySuffix

Parameters

• xsLibrarySuffix (str) – XS library suffix is used to determine which ISOTXS files should be merged together. This can be an empty string or be something like -doppler.

• xsLibFileNames (list) – A list of library names like ISOAA, ISOBA, ISOCA, etc.

Notes

Files that exist: ISOAA-n1, ISOAB-n1, ISOAA-n2, ISOAB-n2, ISOAA, ISOAB, ISODA, ISOBA. xsLibrarySuffix: ‘n2’ Results: ISOAA-n2, ISOAB-n2

armi.nuclearDataIO.xsLibraries.mergeXSLibrariesInWorkingDirectory(lib, xsLibrarySuffix='', mergeGammaLibs=False)

Merge neutron (ISOTXS) and gamma (GAMISO/PMATRX) library data into the provided library.

Parameters

• lib (obj) – ISOTXS library object

• xsLibrarySuffix (str, optional) – XS library suffix used to determine which ISOTXS files are merged together, typically something like -doppler. If empty string, will merge everything without suffix (indicated by a -).

• mergeGammaLibs (bool, optional) – If True, the GAMISO and PMATRX files that correspond to the ISOTXS library will be merged. Note: if these files do not exist this will fail.

class armi.nuclearDataIO.xsLibraries._XSLibrary

Bases: object

Parent class for Isotxs and Compxs library objects.

property neutronEnergyUpperBounds

Get or set the neutron energy groups.

property neutronVelocity

Get or set the mean neutron velocity in cm/s.

merge(other)

_mergeNeutronEnergies(other)

items()

class armi.nuclearDataIO.xsLibraries.IsotxsLibrary

Bases: armi.nuclearDataIO.xsLibraries._XSLibrary

IsotxsLibrary objects are a collection of cross sections (XS) for both neutron and gamma reactions.

IsotxsLibrary objects must be initialized with data through one of the read methods within this package

See also

armi.nuclearDataIO.cccc.isotxs.readBinary(), armi.nuclearDataIO.cccc.gamiso.readBinary(), armi.nuclearDataIO.cccc.pmatrx.readBinary(), CompxsLibrary

Examples

>>> lib = xsLibraries.IsotxsLibrary()
>>> # this doesn't have any information yet, we can read ISOTXS information
>>> libIsotxs = isotxs.readBinary('ISOAA')
>>> # any number of XSLibraries can be merged
>>> lib.merge(libIsotxs) # now the `lib` contains the ISOAA information.

property gammaEnergyUpperBounds

Get or set the gamma energy groups.

property neutronDoseConversionFactors

Get or set the neutron dose conversion factors.

property gammaDoseConversionFactors

Get or set the gamma does conversion factors.

property numGroups

Get the number of neutron energy groups

property numGroupsGamma

get the number of gamma energy groups

property xsIDs

Get the XS ID’s present in this library.

Assumes the suffixes are the last 2 letters in the nucNames

get(nuclideLabel, default)

getNuclide(nucName, suffix)

Get a nuclide object from the XS library or None.

Parameters

• nucName (str) – ARMI nuclide name, e.g. ‘U235’, ‘PU239’

• suffix (str) – Restrict to a specific nuclide lib suffix e.g. ‘AA’

Returns

nuclide – A nuclide from the library or None

Return type

Nuclide object

property nuclideLabels

Get the nuclide Names.

property nuclides

getNuclides(suffix)

Returns a list of the nuclide objects in the library

merge(other)

Merge two XSLibraries

_mergeProperties(other)

_mergeMetadata(other)

_mergeNuclides(other)

resetScatterWeights()

getScatterWeights(scatterMatrixKey='elasticScatter')

Build or retrieve pre-built scatter weight data

This acts like a cache for _buildScatterWeights

See also

_buildScatterWeights()

_buildScatterWeights(scatterMatrixKey)

Build a scatter-weight lookup table for the scatter matrix.

Scatter “weights” are needed for sensitivity studies when deriviatives wrt the scatter XS are required. They are defined like:

\[w_{g^{\prime} \leftarrow g} = \frac{\sigma_{s,g^{\prime} \leftarrow g}} {\sum_{g^{\prime\prime}=1}^G \sigma_{s, g^{\prime\prime} \leftarrow g}}\]

Returns

scatterWeights – (xsID, fromGroup) : weight column (sparse Gx1).

Return type

dict

See also

terrapower.physics.neutronics.uq.sensitivities.MeshMatrix.derivativeM()

plotNucXs(nucNames, xsNames, fName=None, label=None, noShow=False, title=None)

generates a XS plot for a nuclide on the ISOTXS library

nucNamestr or list

The nuclides to plot

xsNamestr or list

the XS to plot e.g. n,g, n,f, nalph, etc. see xsCollections for actual names.

fNamestr, optional

if fName is given, the file will be written rather than plotting to screen

labelstr, optional

is an optional label for image legends, useful in ipython sessions.

noShowbool, optional

Won’t finalize plot. Useful for using this to make custom plots.

Examples

>>> l = ISOTXS()
>>> l.plotNucXs('U238NA','fission')

Plot n,g for all xenon and krypton isotopes >>> f = lambda name: ‘XE’ in name or ‘KR’ in name >>> l.plotNucXs(sorted(filter(f,l.nuclides.keys())),itertools.repeat(‘nGamma’))

See also

armi.nucDirectory.nuclide.plotScatterMatrix()

purgeFissionProducts(r)

Purge the fission products based on the active nuclides within the reactor.

Parameters

• r (py:class:armi.reactors.reactor.Reactor) – a reactor, or None

• warning: (.) – Sometimes worker nodes do not have a reactor, fission products will not be purged.:

class armi.nuclearDataIO.xsLibraries.CompxsLibrary

Bases: armi.nuclearDataIO.xsLibraries._XSLibrary

Library object used in reading/writing COMPXS files.

Contains macroscopic cross sections for homogenized regions.

See also

IsotxsLibrary, armi.nuclearDataIO.cccc.compxs.readBinary()

Examples

>>> lib = compxs.readBinary('COMPXS')
>>> lib.regions

property regions

property regionLabels

merge(other)

Merge two COMPXS libraries.

_mergeProperties(other)

_appendRegions(other)