Sensitivity API

author: N. Abrate.

file: sensitivity.py

description: read sensitivity profiles and construct an object to perform operations.

class pyNDUS.sensitivity.Sensitivity(sensitivity_path, duplicate_policy='raise')[source]

Bases: SensitivityAlgebraMixin

Class to read, store, and process multi-group sensitivity profiles from Serpent or ERANOS output files.

Parameters:: sensitivity_path (str or Path) – Path to the sensitivity file to be read.

filepath

Path to the sensitivity file. -‘serpent’: should end with “_sens0.m”. -‘eranos’: should end with “.eranos33” or “.eranos1968”.

Type:: Path

reader

Sensitivity file format (‘serpent’ or ‘eranos’).

Type:: str

responses

List of response parameters (e.g., ‘keff’, ‘beff’, etc.).

Type:: list

materials

Mapping of material names to their indices.

Type:: OrderedDict

zaid

Mapping of ZAID numbers (e.g., 942390) to their indices.

Type:: OrderedDict

zais

Mapping of ZA strings (e.g., ‘Pu-239’) to their indices.

Type:: OrderedDict

MTs

Mapping of MT numbers (see ENDF-6 format for the numbers) to their indices.

Type:: OrderedDict

group_structure

Energy group structure, stored in ascending order.

Type:: iterable

n_groups

Number of energy groups. Sensitivity arrays are stored in ascending energy order, consistently with group_structure.

Type:: int

sens

Sensitivity profiles whose shape is (nResp, nMat, nZaid, nMTs, nE).

Type:: np.ndarray

sens_rsd

Relative standard deviations of the sensivity profile. When not available (e.g., for deterministic calculations), it is None. The shape is (nResp, nMat, nZaid, nMTs, nE).

Type:: np.ndarray

from_serpent()[source]: Read and parse a Serpent sensitivity file using serpentTools.

from_eranos()[source]: Read and parse an ERANOS sensitivity output file. (its extension must be either “.eranos33” for the ECCO-33 group structure or “.eranos1968” for the ECCO-1968 group structure).

NormalizeSensProfile(sens_profile, energy_vector)[source]: Normalize a sensitivity profile in lethargy.

get(resp=None, mat=None, MT=None, za=None, g=None)[source]: Extract sensitivity profiles and uncertainties for specified parameters. -‘resp’: response(s) to extract (e.g., ‘keff’, ‘beff’). -‘mat’: material(s) to extract (e.g., ‘total’, ‘m1’). -‘MT’: MT number(s) to extract (e.g., 2, 4, 18). -‘za’: ZA string(s) or number(s) to extract (e.g., ‘Pu-239’, 942390). -‘g’: energy group(s) to extract (e.g., 1, 2, …, n_groups).

Raises:: SensitivityError – If the file format is not recognized or if the file structure is not as expected.

__init__(sensitivity_path, duplicate_policy='raise')[source]

Initialize the Sensitivity object and read the sensitivity file.

Parameters:

sensitivity_path (str, Path, or sequence of str/Path) – Path to one sensitivity file, or multiple Serpent *_sens0.m files to merge. -‘serpent’: should end with “_sens0.m”. -‘eranos’: should end with “.eranos33” or “.eranos1968”.
duplicate_policy (str, optional) – Policy for handling duplicate entries in the sensitivity file. Options are: -‘raise’: raise an error if duplicates are found (default). -‘keep_first’: keep the first occurrence and ignore subsequent duplicates. -‘keep_last’: keep the last occurrence and ignore previous duplicates.

from_serpent()[source]

Read and parse a Serpent sensitivity file using serpentTools.

Raises:: SensitivityError – If the file structure is not as expected.

from_eranos()[source]

Read and parse an ERANOS sensitivity output file.

Raises:: SensitivityError – If the file format or structure is not as expected.

static NormalizeSensProfile(sens_profile, energy_vector)[source]

Normalize a sensitivity profile in lethargy.

Parameters:

sens_profile (array-like) – Sensitivity profile (vector of G elements).
energy_vector (array-like) – Energy vector of G+1 limits (not bins).

Returns:

vector – Sensitivity profile per unit lethargy.

Return type:

list

property filepath

Path to the sensitivity file.

Returns:: File path.
Return type:: Path

property is_multifile

Whether this object was initialized from multiple sensitivity files.

Returns:: True when filepath stores a sequence of paths.
Return type:: bool

property reader

Sensitivity file format (‘serpent’ or ‘eranos’).

Returns:: File format.
Return type:: str

get_reader()[source]

Determine the reader type based on the file extension.

Returns:: Reader type (‘serpent’ or ‘eranos’).
Return type:: str
Raises:: SensitivityError – If the file format is not recognized.

property responses

List of response parameters.

Returns:: List of responses.
Return type:: list

property materials

Mapping of material names to their indices.

Returns:: Material names and indices.
Return type:: OrderedDict

property zaid

Mapping of ZAID numbers to their indices.

Returns:: ZAID numbers and indices.
Return type:: OrderedDict

property zais

Mapping of ZA strings to their indices.

Returns:: ZA strings and indices.
Return type:: OrderedDict

property MTs

Mapping of MT numbers to their indices.

Returns:: MT numbers and indices.
Return type:: OrderedDict

property energy_unit

Unit used by the stored energy group structure.

Returns:: Canonical unit label, either "eV" or "MeV".
Return type:: str

property energy_grid

Energy group structure with unit metadata.

Returns:: Stored energy group boundaries and their unit.
Return type:: utils.EnergyGrid

group_structure_as(unit)[source]

Return the energy group structure converted to a requested unit.

Parameters:: unit (str) – Target energy unit. Supported values are "eV" and "MeV".
Returns:: Energy group boundaries converted to unit.
Return type:: numpy.ndarray

property group_structure_ev

Energy group structure converted to eV.

Returns:: Energy group boundaries in eV.
Return type:: numpy.ndarray

property group_structure_mev

Energy group structure converted to MeV.

Returns:: Energy group boundaries in MeV.
Return type:: numpy.ndarray

property group_structure

Energy group structure.

Returns:: Energy group boundaries.
Return type:: iterable

property n_groups

Number of energy groups.

Returns:: Number of groups.
Return type:: int

property n_resp

Number of responses.

Returns:: Number of responses.
Return type:: int

property n_mat

Number of materials.

Returns:: Number of materials.
Return type:: int

property n_zai

Number of isotopes.

Returns:: Number of isotopes.
Return type:: int

property n_MTs

Number of MTs.

Returns:: Number of MTs.
Return type:: int

property sens

Sensitivity profiles.

Returns:: Sensitivity array whose shape is (nResp, nMat, nZaid, nMTs, nE).
Return type:: np.ndarray

property sens_rsd

Relative standard deviations of the sensitivity profiles.

Returns:: Sensitivity array whose shape is (nResp, nMat, nZaid, nMTs, nE).
Return type:: np.ndarray

get(resp=None, mat=None, MT=None, za=None, g=None, group_order='ascending')[source]

Extract sensitivity profiles and uncertainties for specified parameters.

Parameters:

resp (str or list, optional) – Response(s) to extract, e.g., ‘keff’, ‘beff’. If None, all responses are extracted.
mat (str or list, optional) – Material(s) to extract, e.g., ‘total’, ‘m1’. If None, all materials are extracted.
MT (int or list, optional) – MT number(s) to extract, e.g., 2, 4, 18. If None, all MTs are extracted.
za (str, int, or list, optional) – ZA string(s) or number(s) to extract, e.g., ‘Pu-239’, 942390 or [‘Pu-239’, ‘Pu-240’]. If None, all ZAIDs are extracted.
g (int or list, optional) – Energy group(s) to extract, e.g., 1, 2, …, n_groups. If None, all groups are extracted.
group_order ({"ascending", "descending"}, optional) – Order used for the returned energy groups. "ascending" preserves the internal ordering; "descending" reverses it.

Returns:

S_avg (np.ndarray or dict) – Sensitivity profile(s).
S_rsd (np.ndarray or dict, optional) – Sensitivity RSD(s), if available.

collapse(fewgrp, weight=None, egridname=None)[source]

Collapse sensitivity coefficients onto a coarser energy grid.

Parameters:

fewgrp (iterable) – Few-group boundaries used for the collapse.
weight (array-like, optional) – Weighting function used for the energy collapse. If None, a unit weighting vector is used.
egridname (str, optional) – Name of the energy grid, by default None.

Raises:

SensitivityError – If the target grid is incompatible with the current energy grid or the weighting vector length is inconsistent.

Returns:

The object is updated in place.

Return type:

None

exception pyNDUS.sensitivity.SensitivityError[source]

Bases: Exception

Custom exception raised for invalid sensitivity input or processing.