Add release notes for V2 of the primitives

[ihincks]

Summary

Release notes for all of the new features added in V2 of the primitives.

Details and comments

[qiskit-bot]

One or more of the the following people are requested to review this:

• @Qiskit/terra-core
• @ajavadia
• @ikkoham
• @levbishop
• @t-imamichi

[coveralls]

Pull Request Test Coverage Report for Build 7916552177

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 11 (100.0%) changed or added relevant lines in 4 files are covered.
• 182 unchanged lines in 23 files lost coverage.
• Overall coverage increased (+0.02%) to 89.216%

---

Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/expr.rs	1	93.81%
qiskit/synthesis/clifford/clifford_decompose_ag.py	1	98.72%
qiskit/synthesis/clifford/clifford_decompose_full.py	1	87.5%
qiskit/synthesis/linear/cnot_synth.py	1	98.0%
qiskit/synthesis/clifford/clifford_decompose_greedy.py	2	98.88%
qiskit/synthesis/linear/linear_depth_lnn.py	2	98.33%
qiskit/synthesis/stabilizer/stabilizer_decompose.py	2	96.83%
qiskit/synthesis/unitary/qsd.py	2	97.52%
qiskit/synthesis/clifford/clifford_decompose_bm.py	3	97.83%
qiskit/synthesis/cnotdihedral/cnotdihedral_decompose_general.py	3	96.05%

Totals
Change from base Build 7893751411:	0.02%
Covered Lines:	58854
Relevant Lines:	65968

---

💛 - Coveralls

[chriseclectic]

Looks ok, though I wonder if we want to separate bullets for the release note of introducing the new API, and adding the new reference implementations of Sampler and Estimator that probably deserve their own reno including something like the code snippet you added

[ihincks]

Looks ok, though I wonder if we want to separate bullets for the release note of introducing the new API, and adding the new reference implementations of Sampler and Estimator that probably deserve their own reno including something like the code snippet you added

Yeah I wasn't sure of style conventions or expectations of a reno for such a big thing should be, so I decided just to open something as a placeholder and wait for the reviews.

[ihincks]

I split it into three files: one for the new abstract API and container types, and one for each of the new implementations. I made sure that all of the code runs.

[mtreinish]

You don't need to use separate files. You can have multiple release notes in a single file, you just put multiple yaml list entries in the file with each note. For example https://github.com/Qiskit/qiskit/blob/main/releasenotes/notes/add-synth-circuit-from-stabilizer-list-4cf9cfa01bbc7ddf.yaml has 2 feature release notes in one file. You can also have multiple categories of notes in a single file too.

[ihincks]

Just did something dumb with a push. Will fix.

[ihincks]

I'm going to wait for #11227 to merge before attempting to finalize this PR. Then we can do it all at once.

[t-imamichi]

LGTM. We can merge it after #11227 is merged.

[jakelishman]

The last three commits I've just pushed up should fix the docs build. The principal issue is that

.. automodule:: qiskit.primitives.base.base_sampler

is not just a simple "text-only include", it's got some side-effects:

1. It documents qiskit.primitives.base.base_sampler as a public module. There's no obvious user-facing heading included in the output from our own docs build, but it's generated into the Sphinx inventory and into the HTML structure, so later API-documentation processing may well include something.
2. It sets the currentmodule to qiskit.primitives.base.base_sampler until the current module is overridden again. This means that all objects documented below it in the file are attempted to be documented as being under qiskit.primitives.base.base_sampler (which is very much not intended).
3. Autosummary uses the currentmodule to "know" how to import objects. Since this was set to a module from which BaseEstimatorV1, etc etc, couldn't be imported from, it complained.

4269544 puts a currentmodule directive in to fix up that module declaration. 7370fa8 fixes up a couple of minor syntactic mistakes that I happened to spot that probably would have failed the Sphinx build later (or at least would have made the output appear unexpected), and 663dab1 just fixes up some whitespace mistakes.

[chriseclectic]

Looks good. Quickly skimming I noticed a couple of types, and added a couple other suggestions for clarity

[ihincks]

This PR should be ready to merge, from my perspective. There is only the question about whether its worth making the column width smaller for all of the code snippets.

[jakelishman]

There is only the question about whether its worth making the column width smaller for all of the code snippets.

The current styling on docs.quantum.ibm.com should give you 80 columns safely within a release note (assuming it's not within a subbullet or anything), and on my device you get a couple of spare. If you can easily keep it down to (say) 72, the display shouldn't have any problems.

[ihincks]

should give you 80 columns safely within a release note

And do you happen to know for the module documentation as well?

[jakelishman]

It'll be a shade wider, just because there's no bullet using up margin on the left. I don't know what the actual styles target or anything, I just measured it on a live page.

[ihincks]

Thanks, done in cfe2699.

[t-imamichi]

LGTM

[t-imamichi]

The API doc of StatevectorSampler.run and StatevectorEstimator.run look very complicated compared to those of BaseSamplerV2.run and BaseEstimatorV2.run. It would be great if we can simplify those of Statevector{Sampler,Estimator}. But it's not urgent.

BaseEstimatorV2

StatevectorEstimator

[ihincks]

Good spot, that is unfortunate. Do you have any idea how to change it? All of that _NestedSequence stuff is from numpy.typing via ArrayLike.

[t-imamichi]

I'm afraid that I have no idea how to change it. Perhaps @jakelishman can help us if he has time to spare.

[jakelishman]

It's likely something we'd have to do in Sphinx configuration to make it treat type aliases as opaque, linked objects or something. I've not looked into it before, but it's probably hiding away somewhere in the options. It's also possibly a thing that's not properly available to us until we're using a later version of Python for the documentation build, since the Python internal handling of type hints changes quite a lot between versions right now.

[ihincks]

I found this conf option: https://www.sphinx-doc.org/en/master/usage/extensions/autodoc.html#confval-autodoc_type_aliases

I'm not sure if we would want to go down this route.