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Flipping of gate direction in Transpiler for CZ gate

See original GitHub issue

What should we add?

The current version of the transpiler raises the following error when attempting to set the basis gate of a backend as cz

'Flipping of gate direction is only supported for CX, ECR, and RZX at this time, not cz.'

As far as I’m aware and through my own testing flipping of a CZ should be easy to implement as it’s “flip” produces the same unitary operator. There is no direct identity needed.

If this could get added that would be great! I would have done this via a pull request myself but it seems “too easy” of a solution that I must be missing something.

The Qiskit file that would need changing. https://github.com/Qiskit/qiskit-terra/blob/1312624309526812eb62b97e0d47699d46649a25/qiskit/transpiler/passes/utils/gate_direction.py

Issue Analytics

State:
Created a year ago
Comments:8 (3 by maintainers)

Top GitHub Comments

1reaction

eendebakptcommented, Aug 26, 2022

@JMuff22 I encountered the same issue and took the liberty to create a PR based on your code.

0reactions

epelofske-LANLcommented, Dec 17, 2022

I just got this error with some code I am testing: qiskit.transpiler.exceptions.TranspilerError: 'Flipping of gate direction is only supported for CX, ECR, and RZX at this time, not cz.'. My local version of qiskit terra is qiskit-terra==0.20.2; is the fix not in the most current version of terra?