Pennylane-rigetti

Bug fixes

* Fixed a bug caused by the `expand_state` method always assuming that

inactive wires are the least significant bits.
[(73)](https://github.com/PennyLaneAI/pennylane-forest/pull/73)

Contributors

This release contains contributions from (in alphabetical order):

Antal Száva.

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Breaking changes

* For compatibility with PennyLane v0.15, the `analytic` keyword argument
has been removed from all devices. Analytic expectation values can
still be computed by setting `shots=None`.
[(71)](https://github.com/PennyLaneAI/pennylane-forest/pull/71)

* For compatibility with PennyLane v0.15, parametric compilation now depends on
the `requires_grad` attribute of parameters instead of the deprecated
`Variable` class.
[(71)](https://github.com/PennyLaneAI/pennylane-forest/pull/71)

* The circuit hashes used for parametric compilation are computed in
`QVMDevice` instead of in `QubitDevice` defined in Pennylane.
[(71)](https://github.com/PennyLaneAI/pennylane-forest/pull/71)

Contributors

This release contains contributions from (in alphabetical order):

Antal Száva.

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New features since last release

Improvements

* Updated the CI.
[(63)](https://github.com/PennyLaneAI/pennylane-forest/pull/63)

Bug fixes

* Updated the plugin to be compatible with the new core of PennyLane.
[(67)](https://github.com/PennyLaneAI/pennylane-forest/pull/67)
[(68)](https://github.com/PennyLaneAI/pennylane-forest/pull/68)

Documentation

* Adapted the documentation to the PennyLane theme.
[(64)](https://github.com/PennyLaneAI/pennylane-forest/pull/64)

Contributors

This release contains contributions from (in alphabetical order):

Thomas Bromley, Theodor Isacsson, Josh Izaac, Maria Schuld, Antal Száva.

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* Version bump

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New features

* Forest devices now support custom wire labels. 55 57 58 59

One can now specify any string or number as a custom wire label, and use these labels to address subsystems on the device:

python
dev = qml.device('forest.qvm' device='4q-qvm', wires=['q1', 'ancilla', 0, 1])

qml.qnode(dev)
def circuit():
qml.Hadamard(wires='q1')
qml.CNOT(wires=[1, 'ancilla'])
return qml.expval(qml.PauliZ(0))


Bug fixes

* Fixes a bug where basis states were not correctly initialized 56

* Tensor measurements have been fixed due to a change in PL v0.11 52

* The QCS no longer supports lattice-based devices such as Aspen-4-5Q-E. As a result, the `forest.qvm` and `forest.qpu` devices no longer accept lattice-based devices, and must be loaded with the full device name (e.g. Aspen-4). 51

Contributors

Theodor Isacsson, Josh Izaac, Maria Schuld, Antal Száva

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* Adding support for multi-qubit observable estimation.

* Added a new method `analytic_probability()` to the `Wavefunction` simulator devices, so that analytic and non-analytic probabilities are correctly returned.

* Reduced the default number of shots for the `QPUDevice` to 1000 from 1024.

* The test suite now programmatically queries `pyquil.list_quantum_computers()` for valid QPU lattices for integration tests, and additional gradient integration tests have been added.

* The minimum required version of PennyLane has been increased to v0.9 due to plugin API changes in PennyLane.

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