From 52d6b685e8c30719124a093222baed4c3b39d2cd Mon Sep 17 00:00:00 2001 From: John Tramm Date: Fri, 17 Jul 2026 21:50:01 +0000 Subject: [PATCH] Condense the settings parameter docstring to the essential contract Drop the layer-by-layer resolution walkthrough, hard-coded default values, and bootstrap narrative; those live in the user guide and the code itself. Co-Authored-By: Claude Fable 5 --- openmc/model/model.py | 48 +++++++++++-------------------------------- 1 file changed, 12 insertions(+), 36 deletions(-) diff --git a/openmc/model/model.py b/openmc/model/model.py index 0541138660..8cc3ac13b8 100644 --- a/openmc/model/model.py +++ b/openmc/model/model.py @@ -2696,42 +2696,18 @@ class Model: Set ``temperature`` on the object passed via the ``settings`` argument instead. settings : openmc.Settings, optional - Settings for customizing the continuous energy simulation(s) - used to generate the MGXS library. Only attributes that are - populated override the generation defaults, so a sparse object - may be used to adjust just a few fields, e.g. - ``settings=openmc.Settings(particles=100_000)`` only increases - the particle count. The settings of the generation run are - resolved in three layers, with later layers taking precedence: - (1) the model's own settings for the ``"material_wise"`` method, - or a fresh :class:`openmc.Settings` object for the - surrogate-geometry methods (which also inherit the model's - temperature settings); (2) the generation defaults (200 batches - with 100 inactive for ``"material_wise"`` and - ``"stochastic_slab"``, 100 batches for ``"infinite_medium"``, - 2000 particles, and summary-only output); (3) all populated - attributes of this object (see :meth:`openmc.Settings.update`). - The run mode cannot be set here: ``"material_wise"`` always - takes it from the model, while the ``"stochastic_slab"`` and - ``"infinite_medium"`` methods always run in fixed source mode. - The surrogate-geometry methods also construct their own - sources and default ``create_fission_neutrons`` to False - (fission treated as capture). If the resolved settings include a - ``weight_windows_file`` (e.g., ``"weight_windows.h5"``), the - ``"material_wise"`` method loads and applies those weight - windows during the continuous energy generation simulation. - Applying - weight windows allows the simulation to obtain tallies -- and - thus nonzero cross sections -- for materials located far from - the source, for example behind a thick shield, which an analog - simulation may be unable to reach. A typical use case is to - first generate weight windows with the ``"stochastic_slab"`` - method and the random ray solver, then "bootstrap" a - higher-fidelity ``"material_wise"`` library by setting those - weight windows here; a warning is issued and the file is - ignored for the ``"stochastic_slab"`` and ``"infinite_medium"`` - methods. Cannot be combined with the deprecated ``nparticles`` - or ``temperature_settings`` arguments. + Settings overrides for the continuous energy simulation(s) used + to generate the MGXS library. Attributes populated on this + object take precedence over the generation defaults, so a + sparse object such as ``openmc.Settings(particles=100_000)`` + adjusts just that field (see :meth:`openmc.Settings.update`). + The run mode cannot be overridden, as it is determined by the + generation method. A ``weight_windows_file`` is applied during + ``"material_wise"`` generation and ignored with a warning by + the other methods; see the user guide for the weight window + "bootstrapping" workflow this enables. Cannot be combined with + the deprecated ``nparticles`` or ``temperature_settings`` + arguments. .. versionadded:: 0.15.4 """