Add controlled unitary gate #1069
Conversation
Codecov Report
@@ Coverage Diff @@
## master #1069 +/- ##
=======================================
Coverage 97.72% 97.73%
=======================================
Files 154 154
Lines 11655 11679 +24
=======================================
+ Hits 11390 11414 +24
Misses 265 265
Continue to review full report at Codecov.
|
trbromley
added
the
review-ready 👌
There was a problem hiding this comment.
Thanks @trbromley! I might be missing something about how this is supposed to work, but it seems like control/target wires chosen doesn't make a difference, causing the first wires to always be control with the remaining wires at the end targets. 🤔
Co-authored-by: Theodor <theodor@xanadu.ai>
|
Thanks @thisac for the review! Let me know if you're not persuaded regarding the wires question and we can discuss more. |
tests/ops/test_qubit_ops.py
Outdated
| # the 4-qubit representation of the unitary if the control wires were [0, 1] and the target | ||
| # wires were [2, 3] | ||
| U_matrix = np.eye(16, dtype=np.complex128) | ||
| for i in range(4): | ||
| for j in range(4): | ||
| U_matrix[i + 12, j + 12] = U[i, j] |
There was a problem hiding this comment.
Why not use block_diag(np.eye(12, dtype=np.complex128), U)?
There was a problem hiding this comment.
Yes good point, I wanted to do it in a way that's totally different from what's done in ControlledQubitUnitary.
There was a problem hiding this comment.
Understood! Not sure if that's necessary though, since we're not really testing block_diag here. 🤔
There was a problem hiding this comment.
This is looking good @trbromley! 💯 Left some comments mostly related to testing, but nothing major
Co-authored-by: antalszava <antalszava@gmail.com>
This reverts commit a4060d6.
Context:
Adds a new gate,
ControlledQubitUnitary, which allows users to specify the matrix of a unitary, the control wire(s) and the target wire(s).Description of the Change:
This gate has been added as an operation in
pennylane/ops/qubit.py. It inherits fromQubitUnitaryand just performs some tweaks in the__init__.Possible Drawbacks:
The underlying matrix could get quite large if the user specifies a lot of control wires. However this seems anyway expected if we are working in the matrix representation.