Mixed multigrid

[thomasmelvin]

PR Summary

Sci/Tech Reviewer:
Code Reviewer: @mo-rickywong

Allow the multigrid preconditioner to be used on the mixed system of equations

Code Quality Checklist

• I have performed a self-review of my own code
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trac.log

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Performance Impact

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Sci/Tech Review

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Code Review

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[github-actions]

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[mo-rickywong]

@thomasmelvin Just to check, what is the state of this PR? Is this still in progress? There is no SciTech reviewer? Please update the PR if required otherwise it won't be progressed.

[thomasmelvin]

@thomasmelvin Just to check, what is the state of this PR? Is this still in progress? There is no SciTech reviewer? Please update the PR if required otherwise it won't be progressed.

It's still in progress but this isn't targeted for this release (it's very much speculative work for the future)

[mo-rickywong]

@thomasmelvin Just to check, what is the state of this PR? Is this still in progress? There is no SciTech reviewer? Please update the PR if required otherwise it won't be progressed.

It's still in progress but this isn't targeted for this release (it's very much speculative work for the future)

Then I'd suggest this work should be an issue, which can have discussion and a PR attached if code is discussed.
The PR should remain in draft until a decision to put something up for trunk is made. I'll put this into draft