Adding layerwise folding as tutorial to mitiq.

[vprusso]

• Tutorial provided to showcase functionality for layerwise folding and error mitigation.

[github-actions]

👈 Launch a binder notebook on branch unitaryfund/mitiq/layerwise-folding-tutorial

[codecov]

Codecov Report

Merging #1894 (546afb9) into master (3331c2a) will not change coverage.
The diff coverage is n/a.

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  Misses         52       52           

[vprusso]

Not sure if I'm missing something, but all of the tests within the build/docs directory appear to be passing (link), but somehow the whole docs pipeline fails. Is there an obvious reason as to why this might be the case?

[nathanshammah]

Thanks @vprusso! This is a great addition to the documentation.
Regarding the failing tests, it looks like CI doesn't like #step:6:349,

/home/runner/work/mitiq/mitiq/docs/source/examples/layerwise-folding.md:25: WARNING: 'myst' reference target not found: total-variational-distance-metric

/home/runner/work/mitiq/mitiq/docs/source/examples/layerwise-folding.md:26: WARNING: 'myst' reference target not found: impact-of-single-vs.-double-folding
/home/runner/work/mitiq/mitiq/docs/source/examples/layerwise-folding.md:28: WARNING: 'myst' reference target not found: #experiment:-global-folding-with-linear-extrapolation
/home/runner/work/mitiq/mitiq/docs/source/examples/layerwise-folding.md:29: WARNING: 'myst' reference target not found: #experiment:-layerwise-folding-with-linear-extrapolation

Can you please add the file to the index file, at examples.md? It would be great to include a thumbnail too, including a path for it in the conf.py and adding it to the _thumbnails folder. You can check the correct build of the docs here in the CI test list, looking at the RTD build.

[vprusso]

Awesome. Thanks, @nathanshammah. We should be all ✅ now!

[andreamari]

Thanks Vincent, very nice example!
Minor suggestions are given below.

[vprusso]

Thanks again for the comments, @andreamari !

These should all (hopefully) be addressed now. Thank you!

[vprusso]

Thanks for the approval, @andreamari. Any qualms @natestemen , or would you say this is good to go?

[natestemen]

Nice work Vincent, thanks for putting this together.

Biggest thing is just a minor comment about moving some of the motivational context to the beginning of the tutorial.

[natestemen]

I wonder if this motivational material should be moved to the top?

[vprusso]

Good call. Done!

[natestemen]

I see you moved it to the top in 28e0c5f, but wondering if we want remove it from the bottom as well, or it's okay that's it's duplicated.

[vprusso]

Nope, I'm just a fool who left it in there twice. Removed, and thank you for the catch!

[vprusso]

Thanks for the comments, @natestemen !

I believe they have been addressed. Let me know if there's anything else, but if not, I think it's good to go!

[natestemen]

[vprusso]

Awesome, thanks for the approval, @natestemen. I believe things are good (although it seems like the docs are failing for some odd reason). I know that they sometimes do this, so I'm not sure if this is just an artifact of something unrelated.

I attempted to rerun the docs build, but it still seems to fail. It mentions something about bsqkit (which I didn't touch in my MR):

/home/runner/work/mitiq/mitiq/docs/source/examples/bqskit.md: WARNING: Executing notebook failed: CellExecutionError [mystnb.exec]
/home/runner/work/mitiq/mitiq/docs/source/examples/bqskit.md: WARNING: Notebook exception traceback saved in: /home/runner/work/mitiq/mitiq/docs/build/html/reports/examples/bqskit.err.log [mystnb.exec]

Is it okay to merge or should I hold off?

[natestemen]

Yup that's a problem that we are seeing across all PRs are the moment, so no need to worry about that. Sorry for the confusion. I'll let you hit the merge button when you want since it's fun :)

[vprusso]

It is fun! :) Away it goes 🚀