[mergify]

Summary

close #15610 .

Since iterative Quantum Shannon Decomposition may provide imprecise matrices, and the rust code may panic when calcualting SVD or Schur decompositions, we use the Isometry decomposition in such cases.

Details and comments

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This is an automatic backport of pull request #15635 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 02fef9b has failed:

On branch mergify/bp/stable/2.3/pr-15635
Your branch is up to date with 'origin/stable/2.3'.

You are currently cherry-picking commit 02fef9ba2.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   releasenotes/notes/fix-panic-qsd-and-use-isometry-df29b8304951a586.yaml
	modified:   test/python/circuit/test_controlled_gate.py

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   crates/synthesis/src/qsd.rs
	both modified:   qiskit/circuit/library/generalized_gates/unitary.py

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[Coveralls (coveralls)]

Pull Request Test Coverage Report for Build 23024350432

Details

• 22 of 27 (81.48%) changed or added relevant lines in 2 files are covered.
• 22 unchanged lines in 5 files lost coverage.
• Overall coverage decreased (-0.009%) to 88.371%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
crates/synthesis/src/qsd.rs	8	10	80.0%
qiskit/circuit/library/generalized_gates/unitary.py	14	17	82.35%

Files with Coverage Reduction	New Missed Lines	%
crates/circuit/src/parameter/parameter_expression.rs	1	82.42%
crates/circuit/src/parameter/symbol_expr.rs	1	74.0%
crates/qasm2/src/expr.rs	1	93.82%
crates/qasm2/src/lex.rs	7	91.77%
crates/qasm2/src/parse.rs	12	97.15%

Totals
Change from base Build 23021600454:	-0.009%
Covered Lines:	96746
Relevant Lines:	109477

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💛 - Coveralls