Docs: Fix doctest failure in rms.py

[IAyaanHere]

Contributes to #3925

Changes made in this Pull Request:

• Fixed rms.py doctest failure by updated the expected output to np.float64(6.838544558398293) so it lines up with what NumPy actually returns
• Verified that the doctest passes using pytest --doctest-modules.

LLM / AI generated code disclosure

• No

PR Checklist

• Issue raised/referenced?
• Tests updated/added?
• Documentation updated/added?

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📚 Documentation preview 📚: https://mdanalysis--5205.org.readthedocs.build/en/5205/

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.73%. Comparing base (9cbc8ea) to head (71eab77).
⚠️ Report is 25 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #5205   +/-   ##
========================================
  Coverage    92.72%   92.73%           
========================================
  Files          180      180           
  Lines        22475    22475           
  Branches      3190     3190           
========================================
+ Hits         20841    20843    +2     
+ Misses        1177     1176    -1     
+ Partials       457      456    -1     

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[orbeckst]

Can you show the output of the doc testing before and after your fix?

[orbeckst]

See comments inline.

Please also show explicitly doc tests output before/after your change.

[orbeckst]

Nobody would normally case the output with float. First and foremost, the docs must be human-readable/human-centered. If the output is different then you could show the different output.

Find a way to make the doc-tests work without introducing code in the example that only serves the doc tests.

[IAyaanHere]

Thanks for pointing that out, @orbeckst You’re right the float() cast was making the example look a bit off.

I’ve switched the example back to rmsd(A, B, center=True) and updated the expected output to np.float64(6.838544558398293) so it lines up with what NumPy actually returns , I tested it locally and the doctests are passing now.

[orbeckst]

Can you please copy and paste how you ran the local test and the relevant output? Thanks.

[IAyaanHere]

Can you please copy and paste how you ran the local test and the relevant output? Thanks.

yeah sure @orbeckst , here are the local doctest outputs as requested:

Before (Failing):
The test fails because the returned value is a numpy scalar, but the docstring expected a standard float so we got ,

package\MDAnalysis\analysis\rms.py F                                                            [100%]

============================================== FAILURES ============================================== 
_______________________________ [doctest] MDAnalysis.analysis.rms.rmsd _______________________________ 
246 >>> rmsd(A, B, center=True)
Expected:
    6.838544558398293
Got:
    np.float64(6.838544558398293)

D:\study zone\pandas\mdanalysis\package\MDAnalysis\analysis\rms.py:246: DocTestFailure
====================================== short test summary info =======================================
FAILED package\MDAnalysis\analysis\rms.py::MDAnalysis.analysis.rms.rmsd


**After (Passing):**

after updating the expected output to np.float64(6.838544558398293) and removing the unnecessary float() cast: ,


```package\MDAnalysis\analysis\rms.py .                                                            [100%]

==================================== 1 passed, 1 warning in 3.82s ====================================

[orbeckst]

Thank you for the fix! LGTM