use XXPlusYYGate in excitation_preserving #14128

kevinsung · 2025-03-28T22:30:32Z

Summary

Fixes #14125

Details and comments

qiskit-bot · 2025-03-28T22:30:36Z

One or more of the following people are relevant to this code:

@Cryoris
@Qiskit/terra-core
@ajavadia

coveralls · 2025-03-28T22:54:07Z

Pull Request Test Coverage Report for Build 14271767169

Details

11 of 11 (100.0%) changed or added relevant lines in 2 files are covered.
23 unchanged lines in 3 files lost coverage.
Overall coverage decreased (-0.02%) to 88.061%

Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/unitary_synthesis.rs	1	94.79%
crates/qasm2/src/lex.rs	4	92.73%
crates/qasm2/src/parse.rs	18	96.68%

Totals
Change from base Build 14243929141:	-0.02%
Covered Lines:	72895
Relevant Lines:	82778

💛 - Coveralls

ShellyGarion · 2025-03-30T07:02:04Z

Thanks for this contribution to Qiskit.

Currently there are two classes: ExcitationPreserving (which is going to be deprecated in Qiskit 3.0) and the new excitation_preserving class.
By updating only one of them, they will have a somewhat different behavior (when calling ansatz.decompose(), see an example below), which might confuse the users. I would suggest to update both classes.
Could you please add release notes?
I would also suggest to add this equivalence (of XXplusYY to rxx+ryy) to the equivalence library, since currently the basic translator outputs somewhat different circuits (see below).
Please also add a relevant test for the transpilation. Note that your synthesis improves the CX gate count in this case (see below).

ShellyGarion · 2025-03-30T07:05:47Z

from qiskit.circuit.library import *
from qiskit.transpiler import generate_preset_pass_manager

ansatz = excitation_preserving(3, reps=1, insert_barriers=True, entanglement="linear")
pm = generate_preset_pass_manager(
            optimization_level=0, basis_gates=["u", "cx"], seed_transpiler=12345)
transpiled_circuit = pm.run(ansatz)
pm = generate_preset_pass_manager(
            optimization_level=0, basis_gates=["u", "rzz"], seed_transpiler=12345)
transpiled_circuit2 = pm.run(ansatz)
print (ansatz)
print (ansatz.decompose())
print (ansatz.decompose().decompose().count_ops())
print (transpiled_circuit.count_ops())
print (transpiled_circuit2.count_ops())

The current code outputs:


     ┌──────────┐ ░ ┌────────────────────┐                       ░ ┌──────────┐
q_0: ┤ Rz(θ[0]) ├─░─┤0                   ├───────────────────────░─┤ Rz(θ[5]) ├
     ├──────────┤ ░ │  Interaction(θ[3]) │┌────────────────────┐ ░ ├──────────┤
q_1: ┤ Rz(θ[1]) ├─░─┤1                   ├┤0                   ├─░─┤ Rz(θ[6]) ├
     ├──────────┤ ░ └────────────────────┘│  Interaction(θ[4]) │ ░ ├──────────┤
q_2: ┤ Rz(θ[2]) ├─░───────────────────────┤1                   ├─░─┤ Rz(θ[7]) ├
     └──────────┘ ░                       └────────────────────┘ ░ └──────────┘
global phase: -θ[0]/2 - θ[1]/2 - θ[2]/2 - θ[5]/2 - θ[6]/2 - θ[7]/2
     ┌──────────┐ ░ ┌────────────┐┌────────────┐                             ░ »
q_0: ┤ U1(θ[0]) ├─░─┤0           ├┤0           ├─────────────────────────────░─»
     ├──────────┤ ░ │  Rxx(θ[3]) ││  Ryy(θ[3]) │┌────────────┐┌────────────┐ ░ »
q_1: ┤ U1(θ[1]) ├─░─┤1           ├┤1           ├┤0           ├┤0           ├─░─»
     ├──────────┤ ░ └────────────┘└────────────┘│  Rxx(θ[4]) ││  Ryy(θ[4]) │ ░ »
q_2: ┤ U1(θ[2]) ├─░─────────────────────────────┤1           ├┤1           ├─░─»
     └──────────┘ ░                             └────────────┘└────────────┘ ░ »
«     ┌──────────┐
«q_0: ┤ U1(θ[5]) ├
«     ├──────────┤
«q_1: ┤ U1(θ[6]) ├
«     ├──────────┤
«q_2: ┤ U1(θ[7]) ├
«     └──────────┘
OrderedDict({'h': 8, 'cx': 8, 'rx': 8, 'u3': 6, 'rz': 4, 'barrier': 2})
OrderedDict({'u': 26, 'cx': 8, 'barrier': 2})
OrderedDict({'u': 22, 'rzz': 4, 'barrier': 2})

The new code outputs:

     ┌──────────┐ ░ ┌────────────────────┐                       ░ ┌──────────┐
q_0: ┤ Rz(θ[0]) ├─░─┤0                   ├───────────────────────░─┤ Rz(θ[5]) ├
     ├──────────┤ ░ │  Interaction(θ[3]) │┌────────────────────┐ ░ ├──────────┤
q_1: ┤ Rz(θ[1]) ├─░─┤1                   ├┤0                   ├─░─┤ Rz(θ[6]) ├
     ├──────────┤ ░ └────────────────────┘│  Interaction(θ[4]) │ ░ ├──────────┤
q_2: ┤ Rz(θ[2]) ├─░───────────────────────┤1                   ├─░─┤ Rz(θ[7]) ├
     └──────────┘ ░                       └────────────────────┘ ░ └──────────┘
global phase: -θ[0]/2 - θ[1]/2 - θ[2]/2 - θ[5]/2 - θ[6]/2 - θ[7]/2
     ┌──────────┐ ░ ┌────────────────────┐                       ░ ┌──────────┐
q_0: ┤ U1(θ[0]) ├─░─┤0                   ├───────────────────────░─┤ U1(θ[5]) ├
     ├──────────┤ ░ │  (XX+YY)(2*θ[3],0) │┌────────────────────┐ ░ ├──────────┤
q_1: ┤ U1(θ[1]) ├─░─┤1                   ├┤0                   ├─░─┤ U1(θ[6]) ├
     ├──────────┤ ░ └────────────────────┘│  (XX+YY)(2*θ[4],0) │ ░ ├──────────┤
q_2: ┤ U1(θ[2]) ├─░───────────────────────┤1                   ├─░─┤ U1(θ[7]) ├
     └──────────┘ ░                       └────────────────────┘ ░ └──────────┘
OrderedDict({'rz': 12, 'u3': 6, 'cx': 4, 'ry': 4, 'barrier': 2, 's': 2, 'sx': 2, 'sdg': 2, 'sxdg': 2})
OrderedDict({'u': 30, 'cx': 4, 'barrier': 2})
OrderedDict({'u': 46, 'rzz': 4, 'barrier': 2}

kevinsung · 2025-04-04T02:57:03Z

Thanks for this contribution to Qiskit.

1. Currently there are two classes: `ExcitationPreserving` (which is going to be deprecated in Qiskit 3.0) and the new `excitation_preserving` class.
   By updating only one of them, they will have a somewhat different behavior (when calling `ansatz.decompose()`, see an example below), which might confuse the users. I would suggest to update both classes.

2. Could you please add release notes?

3. I would also suggest to add this equivalence (of XXplusYY to rxx+ryy) to the equivalence library, since currently the basic translator outputs somewhat different circuits (see below).

4. Please also add a relevant test for the transpilation. Note that your synthesis improves the CX gate count in this case (see below).

Done.

kevinsung · 2025-04-04T02:59:07Z

qiskit/circuit/library/n_local/excitation_preserving.py

@@ -116,8 +116,7 @@ def excitation_preserving(
    theta = Parameter("θ")
    if num_qubits > 1:
        swap = QuantumCircuit(2, name="Interaction")
-        swap.rxx(theta, 0, 1)
-        swap.ryy(theta, 0, 1)
+        swap.append(XXPlusYYGate(2 * theta), [0, 1])


The factor of 2 is ugly but I added it to maintain equivalence with the previous code.

test/python/circuit/library/test_nlocal.py

ShellyGarion

Thanks for this contribution.
I have two minor comments, but other than that this PR looks good.
@Cryoris - do you have any further comments?

test/python/circuit/library/test_nlocal.py

releasenotes/notes/excitation-preserving-xx-plus-yy-7c72028cd09f9d04.yaml

use XXPlusYYGate in excitation_preserving

bf4fac4

kevinsung requested a review from a team as a code owner March 28, 2025 22:30

kevinsung added 8 commits April 3, 2025 17:45

update ExcitationPreserving too

0107e22

add release note

17cffc0

add transpilation test

c47d1f2

format

a37245b

add equivalence library entry

8619e79

remove unused imports

ccaeb3c

edit release note

62b0d2d

Merge branch 'main' into excitation-preserving

929547c

kevinsung commented Apr 4, 2025

View reviewed changes

Cryoris reviewed Apr 4, 2025

View reviewed changes

test/python/circuit/library/test_nlocal.py Outdated Show resolved Hide resolved

theta -> θ

277ec61

ShellyGarion reviewed Apr 6, 2025

View reviewed changes

test/python/circuit/library/test_nlocal.py Outdated Show resolved Hide resolved

releasenotes/notes/excitation-preserving-xx-plus-yy-7c72028cd09f9d04.yaml Outdated Show resolved Hide resolved

kevinsung added 3 commits April 6, 2025 07:32

fix spacing

f7820e2

move release note to upgrade_circuits

f508d89

fix equivalence diagram

9e15fd2

ShellyGarion approved these changes Apr 6, 2025

View reviewed changes

kevinsung enabled auto-merge April 6, 2025 12:35

kevinsung added this pull request to the merge queue Apr 6, 2025

Merged via the queue into Qiskit:main with commit 95a10e2 Apr 6, 2025
23 of 24 checks passed

kevinsung deleted the excitation-preserving branch April 6, 2025 13:20

eliarbel added the Changelog: Bugfix Include in the "Fixed" section of the changelog label Jun 3, 2025

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

use XXPlusYYGate in excitation_preserving #14128

use XXPlusYYGate in excitation_preserving #14128

Uh oh!

kevinsung commented Mar 28, 2025

Uh oh!

qiskit-bot commented Mar 28, 2025

Uh oh!

coveralls commented Mar 28, 2025 •

edited

Loading

Uh oh!

ShellyGarion commented Mar 30, 2025 •

edited

Loading

Uh oh!

ShellyGarion commented Mar 30, 2025

Uh oh!

kevinsung commented Apr 4, 2025

Uh oh!

kevinsung Apr 4, 2025

Uh oh!

Uh oh!

ShellyGarion left a comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

use XXPlusYYGate in excitation_preserving #14128

use XXPlusYYGate in excitation_preserving #14128

Uh oh!

Conversation

kevinsung commented Mar 28, 2025

Summary

Details and comments

Uh oh!

qiskit-bot commented Mar 28, 2025

Uh oh!

coveralls commented Mar 28, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Pull Request Test Coverage Report for Build 14271767169

Details

💛 - Coveralls

Uh oh!

ShellyGarion commented Mar 30, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

ShellyGarion commented Mar 30, 2025

Uh oh!

kevinsung commented Apr 4, 2025

Uh oh!

kevinsung Apr 4, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

ShellyGarion left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

coveralls commented Mar 28, 2025 •

edited

Loading

ShellyGarion commented Mar 30, 2025 •

edited

Loading