Repository navigation
Fix type hinting and simplify implementation of combine_distributions - #3445
Merged
Merged
Conversation
GuySten
marked this pull request as ready for review
June 16, 2025 16:17
paulromano
reviewed
Jan 16, 2026
paulromano
left a comment
paulromano
left a comment
Contributor
There was a problem hiding this comment.
There are a few problems with this PR in my opinion. First, multiple normal distributions cannot be merged together as the combined distribution would not be normally distributed. The more fundamental issue is that for combine_distributions, it was never intended to handle distributions other than Discrete/Tabular as those are the only ones currently that are allowed have a non-unity integral. I think for now, the proper solution to #3105 is to simply check that the distributions passed to combine_distributions are either Discrete or Tabular and update the type hint.
Contributor
Author
|
I've fixed the type hinting, added type checking and simplified the implementation a bit. |
paulromano
changed the title
paulromano
approved these changes
Jan 21, 2026
Contributor
|
Howdy, I am using a JEFF-3.3 chain, there are photon mixture distributions for: I also see many of these are on the official JEFF-4.0 chains (https://openmc.org/data/#jeff-4-0-1) I guess previously it was silently failing? Where it fails: File "/home/etc/OMC-mR2S_v6.py", line 918, in <module>
generate_photon_sources_mpi(args.model_photon, args.campaign, args.dose_function, args.directory)
~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/etc/OMC-mR2S_v6.py", line 588, in generate_photon_sources_mpi
photon_energy = material.get_decay_photon_energy(
clip_tolerance=1e-4,
units='Bq',
exclude_nuclides=exclude_nuc
)
File "/home/pe427y/Codes/py313/lib64/python3.13/site-packages/openmc/material.py", line 401, in get_decay_photon_energy
combined = openmc.data.combine_distributions(dists, probs)
File "/home/pe427y/Codes/py313/lib64/python3.13/site-packages/openmc/stats/univariate.py", line 1922, in combine_distributions
cv.check_type(f'dists[{i}]', dist, (Discrete, Tabular))
~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/pe427y/Codes/py313/lib64/python3.13/site-packages/openmc/checkvalue.py", line 41, in check_type
raise TypeError(msg)
TypeError: Unable to set "dists[809]" to "<openmc.stats.univariate.Mixture object at 0x7f5d6d108850>" which is not one of the following types: "Discrete, Tabular"
Traceback (most recent call last):The problematic photon source mixture on a JEFF-3.3 chain file: <nuclide name="U235" half_life="2.22102e+16" decay_modes="2" decay_energy="4678887.7" reactions="12">
<decay type="alpha" target="Th231" branching_ratio="1.0"/>
<decay type="sf" target="U235" branching_ratio="7.2e-11"/>
<source type="mixture" particle="photon">
<pair probability="1.0">
<dist type="tabular" interpolation="histogram">
<parameters>0.0 140000.0 300000.0 500000.0 700000.0 1000000.0 1500000.0 2000000.0 2500000.0 3000000.0 4000000.0 5000000.0 6000000.0 7000000.0 10000000.0 5.189951678644752e-33 1.6796690775253955e-32 1.8548490651832704e-32 1.603596506230337e-32 9.033942537964795e-33 4.713505853171821e-33 2.182070655791734e-33 1.3136836990653461e-33 8.28217209559098e-34 3.8235372393008833e-34 1.4399330328638888e-34 5.368003528935868e-35 2.111046096044921e-35 1.2821985662241311e-36 0.0</parameters>
</dist>
</pair>
<pair probability="1.0">
<dist type="discrete">
<parameters>4176.0 13409.0 19595.0 31580.0 34550.0 40900.0 41950.0 51180.0 54030.0 54180.0 64350.0 72500.0 74950.0 89953.0 93350.0 96130.0 104831.0 105610.0 108600.0 109180.0 115900.0 119990.0 136700.0 140760.0 142600.0 143760.0 150940.0 163360.0 172270.0 182520.0 185714.0 194940.0 198930.0 202110.0 205310.0 215290.0 221400.0 228780.0 233470.0 240880.0 246870.0 266470.0 275130.0 275430.0 281450.0 282960.0 289560.0 290200.0 291700.0 301740.0 317080.0 343740.0 345880.0 356050.0 387830.0 410230.0 448330.0 2.413878143615725e-18 7.226080110994538e-18 1.9602063201128385e-21 5.346017236671377e-21 7.662624705895642e-22 8.91002872778563e-21 1.6038051710014132e-20 8.019025855007066e-21 5.346017236671378e-22 8.91002872778563e-21 5.346017236671377e-21 3.564011491114252e-20 1.782005745557126e-20 1.1301130903045706e-18 1.8435770088742827e-18 2.851209192891402e-20 2.1385504538004174e-19 4.07430178788491e-19 2.212293034819278e-19 5.025256202471095e-19 1.782005745557126e-20 8.019025855007066e-21 3.564011491114252e-21 6.237020109449941e-20 1.6038051710014134e-21 3.4161050142330107e-18 2.3166074692242635e-20 1.582421102054728e-18 1.9602063201128385e-21 1.229583964434417e-19 1.782005745557126e-17 1.995846435023981e-19 1.1404836771565607e-20 3.3679908591029683e-19 1.5628190388535994e-18 8.91002872778563e-21 3.7065719507588217e-20 2.3166074692242635e-21 1.1226636197009894e-20 2.3166074692242635e-20 1.7998258030126973e-20 1.9602063201128385e-21 1.2474040218899881e-20 5.346017236671378e-22 1.9602063201128385e-21 1.6038051710014134e-21 1.0692034473342756e-21 1.2474040218899881e-21 1.2474040218899881e-20 1.6038051710014134e-21 3.564011491114252e-22 1.0692034473342756e-21 1.2474040218899881e-20 1.6038051710014134e-21 1.2474040218899881e-20 1.0692034473342756e-21 3.564011491114252e-22</parameters>
</dist>
</pair>
</source> |
5 tasks done
jon-proximafusion
pushed a commit
to shimwell/openmc
that referenced
this pull request
Apr 13, 2026
…openmc-dev#3445) Co-authored-by: Paul Romano <paul.k.romano@gmail.com>
apingegno
pushed a commit
to apingegno/openmc
that referenced
this pull request
May 7, 2026
…openmc-dev#3445) Co-authored-by: Paul Romano <paul.k.romano@gmail.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Description
This pr change the implementation of combine_distributions to support combination of any Univariate distributions with specified probabilities.
The new implementation knows to combine analytically discrete and normal distributions.
Fixes #3105
Checklist