catalyst icon indicating copy to clipboard operation
catalyst copied to clipboard

[BUG] `qml.probs` on Amazon Braket device without shots raises cryptic error

Open dime10 opened this issue 1 year ago • 0 comments

dev = qml.device("braket.local.qubit", wires=2)

@qjit
@qml.qnode(dev)
def f(x: float):
    qml.PSWAP(x, wires=[0, 1])
    qml.ISWAP(wires=[1, 0])
    return qml.probs()

f(0.3)

The circuit raises a cryptic error that does not make it clear what the problem is:

RuntimeError: [OpenQasmRunner.hpp][Line:217][Function:Probs] Error in Catalyst Runtime: 'NoneType' object has no attribute 'items'

The same circuit with shots= set in the device works. But I also tested qml.probs without shots with just PennyLane and Braket and it seems to work, so I think there is a bug on our side.

dime10 avatar Jan 12 '24 11:01 dime10