openmc.lib.WeightWindows

class openmc.lib.WeightWindows(id=None, new=True, index=None)[source]

WeightWindows stored internally.

This class exposes a weight windows object that is stored internally in the OpenMC library. To obtain a view of a weight windows object with a given ID, use the openmc.lib.weight_windows mapping.

Added in version 0.14.0.

Parameters:

  • id (int or None) – Unique ID of the weight windows

  • new (bool) – When index is None, this argument controls whether a new object is created or a view of an existing object is returned.

  • index (int or None) – Index in the weight_windows array.

Variables:

  • id (int) – ID of the weight windows object

  • mesh (openmc.lib.Mesh) – Mesh used for the weight windows

  • particle (openmc.ParticleType) – The particle type to which these weight windows apply

  • energy_bounds (numpy.ndarray) – The energy bounds for the weight windows

  • bounds (numpy.ndarray) – The weight window bounds

classmethod from_tally(tally, particle=<ParticleType: neutron (PDG=2112)>)[source]

Create an instance of the WeightWindows class based on the specified tally.

Parameters:

  • tally (openmc.lib.Tally) – The tally used to create the WeightWindows instance.

  • particle (openmc.ParticleType or str or int, optional) – The particle type to use for the WeightWindows instance. Should be specified as an instance of ParticleType, a PDG number, or as a name.

Returns:

The WeightWindows instance created from the specified tally.

Return type:

WeightWindows

Raises:

  • ValueError – If the particle parameter is not an instance of ParticleType, a string, or an integer PDG number.

  • ValueError – If the particle parameter is not a valid particle type (i.e., not ‘neutron’ or ‘photon’).

  • ValueError – If the specified particle is not included in the bins of the ParticleFilter of the tally.

  • ValueError – If the tally does not have a MeshFilter.

update_magic(tally, value='mean', threshold=1.0, ratio=5.0)[source]

Update weight window values using the MAGIC method

Reference: https://inis.iaea.org/records/231pm-zzy35

Parameters:

  • tally (openmc.lib.Tally object) – The tally used to update weight window information

  • value (str) – Value type used to generate weight windows. One of {‘mean’, ‘rel_err’}.

  • threshold (float) – Threshold for relative error of results used to generate weight window bounds

  • ratio (float) – Ratio of the lower to upper weight window bounds