Fix log field

[Mike Hobson (mike-hobson)]

PR Summary

Sci/Tech Reviewer: Matthew Hambley (@MatthewHambley)
Code Reviewer: Ed Hone (@EdHone)

The log_field() functionality in utilities/log_field_mod.f90 is not working so needs fixing. It is only provided for debugging purposes, so is not routinely called from any application and currently has no unit test. This has allowed the code to become stale and stop working.

Obviously, the code needs fixing, but also a unit test should be added to prevent the code from becoming stale again in the future.

This function can produce a lot of output, so it would also be useful to allow log_field() to only output a section of the field data

• closes Reinstate the log_field functionality #342

Code Quality Checklist

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trac.log

Test Suite Results - lfric_core - fix_log_field/run5

Suite Information

Item	Value
Suite Name	fix_log_field/run5
Suite User	mike.hobson
Workflow Start	2026-04-24T08:30:13
Groups Run	all

Dependency	Reference	Main Like
lfric_core	mike-hobson/lfric_core@fix_log_field	False
SimSys_Scripts	MetOffice/SimSys_Scripts@cab3315	True

Task Information

✅ succeeded tasks - 388

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Code Review

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[Matthew Hambley (MatthewHambley)]

This is a straight forward change which not only fixes a bug but adds some additional flexibility to the call.