Unitary doesnt accept int param for single qubit unitary matrix

[Manvi-Agrawal]

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Cuurently circ = Circuit().unitary(matrix=np.array([[0, 1],[1, 0]]), targets=0) is compile-time error on dev variant based on branch in

#993

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• Amazon Braket Python SDK version:
• Amazon Braket Python Schemas version:
• Amazon Braket Python Default Simulator version:
• Python version:

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See #993 (comment)

[peterkomar-aws]

Hi @Manvi-Agrawal , thanks for pointing this out. You are right that the following code

import numpy as np
from braket.circuits import Circuit

circ = Circuit().unitary(matrix=np.array([[0, 1],[1, 0]]), targets=0)

raises the following TypeError:

...
-> 3621 if 2 ** len(targets) != matrix.shape[0]:
   3622     raise ValueError("Dimensions of the supplied unitary are incompatible with the targets")
   3624 return Instruction(Unitary(matrix, display_name), target=targets)

TypeError: object of type 'int' has no len()

While surprising, this is not unexpected. The docstring of Circuit.unitary says

...
Args:
    targets (QubitSet): Target qubits.
...

In alignment with this, the following code work without error:

import numpy as np
from braket.circuits import Circuit, QubitSet

target_qubit_indexes = (0,)
target_qubits = QubitSet(target_qubit_indexes)

circ0 = Circuit().unitary(matrix=np.array([[0, 1],[1, 0]]), targets=target_qubit_indexes)
circ1 = Circuit().unitary(matrix=np.array([[0, 1],[1, 0]]), targets=target_qubits)

I close this issue. If you think there is more to this problem than what I found, feel free to reopen and provide more information. Thanks.