Resolve runtime warning: invalid value encountered in cast

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#5,533 2 comments 0 reactions 0 assignees View on GitHub

@ukmo-ccbunney is already working on this.

Since Jun 19, 2026.

  • #7161 by @ukmo-ccbunney — open

Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
25/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
numpy, python
Domain
data, testing-qa

Research direction

Start with the warning locations in lib/iris/analysis/_regrid.py and the tests listed in the report, especially test_RectilinearRegridder.py and test_MAX_RUN.py. Check the open pull request #7161 for the work already underway. Done means the affected tests run without the reported invalid-value cast warnings.

Written by the indexing model from the issue text.

Description

Type: Infrastructure Type: Tech Debt

📰 Custom Issue

Written up from #5465.

lib/iris/tests/unit/analysis/test_MAX_RUN.py: 38 warnings
  /home/h05/achamber/.conda/envs/iris-dev/lib/python3.11/site-packages/numpy/core/numeric.py:407: RuntimeWarning: invalid value encountered in cast
    multiarray.copyto(res, fill_value, casting='unsafe')

lib/iris/tests/unit/analysis/regrid/test_RectilinearRegridder.py::Test__regrid__extrapolation_modes::test_method_result_types
  /net/home/h05/achamber/git/iris/lib/iris/analysis/_regrid.py:836: RuntimeWarning: invalid value encountered in cast
    data[tuple(index)] = interpolate(src_subset)
Dominant language
Python
Stars
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Forks
317
Avg merge
3d 20h
Merged PRs (30d)
9

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