Merge branch 'master' into ad/shot-allocation-split-non-commuting

doc/_static/draw_mpl/draw_mpl_examples.py

@@ -102,7 +102,7 @@ def rcparams(circuit):
 
 def use_style(circuit):
 
-    fig, ax = qml.draw_mpl(circuit, style='sketch')(1.2345, 1.2345)
+    fig, ax = qml.draw_mpl(circuit, style="sketch")(1.2345, 1.2345)
 
     plt.savefig(folder / "sketch_style.png")
     plt.close()
@@ -128,6 +128,26 @@ def circuit():
     plt.close()
 
 
+@qml.transforms.merge_rotations
+@qml.transforms.cancel_inverses
+@qml.qnode(qml.device("default.qubit"), diff_method="parameter-shift")
+def _levels_circ():
+    qml.RandomLayers([[1.0, 20]], wires=(0, 1))
+    qml.Permute([2, 1, 0], wires=(0, 1, 2))
+    qml.PauliX(0)
+    qml.PauliX(0)
+    qml.RX(0.1, wires=0)
+    qml.RX(-0.1, wires=0)
+    return qml.expval(qml.PauliX(0))
+
+
+def levels():
+    for level in ("top", "user", None, slice(1, 2)):
+        draw_mpl(_levels_circ, level=level)()
+        plt.savefig(folder / f"level_{str(level).split('(')[0].lower()}.png")
+        plt.close
+
+
 if __name__ == "__main__":
 
     dev = qml.device("lightning.qubit", wires=(0, 1, 2, 3))
@@ -151,3 +171,4 @@ def circuit(x, z):
     rcparams(circuit)
     wires_labels(circuit)
     mid_measure()
+    levels()

doc/code/qml_noise.rst

@@ -4,6 +4,8 @@ qml.noise
 This module contains the functionality for building and manipulating insertion-based noise models,
 where noisy gates and channels are inserted based on the target operations.
 
+.. _intro_noise_model:
+
 Overview
 --------
 
@@ -22,7 +24,13 @@ noise-related metadata can also be supplied to construct a noise model using:
 Each conditional in the ``model_map`` evaluates the gate operations in the quantum circuit based on
 some condition of its attributes (e.g., type, parameters, wires, etc.) and use the corresponding
 callable to apply the noise operations, using the user-provided metadata (e.g., hardware topologies
-or relaxation times), whenever the condition results true.
+or relaxation times), whenever the condition results true. A noise model once built can be attached
+to a circuit or device via the following transform:
+
+.. autosummary::
+    :toctree: api
+
+    ~add_noise
 
 .. _intro_boolean_fn:
 

doc/releases/changelog-dev.md

@@ -47,34 +47,59 @@
 * The `default.tensor` device is introduced to perform tensor network simulations of quantum circuits using the `mps` (Matrix Product State) method.
   [(#5699)](https://github.com/PennyLaneAI/pennylane/pull/5699)
 
-* Added `from_openfermion` to convert openfermion `FermionOperator` objects to PennyLane `FermiWord` or
-`FermiSentence` objects.
-[(#5808)](https://github.com/PennyLaneAI/pennylane/pull/5808)
-
-  ```python
-  of_op = openfermion.FermionOperator('0^ 2')
-  pl_op = qml.from_openfermion(of_op)
+* A new `qml.noise` module which contains utility function for building `NoiseModels` 
+  and an `add_noise` tranform for addding it to quantum circuits.
+  [(#5674)](https://github.com/PennyLaneAI/pennylane/pull/5674)
+  [(#5684)](https://github.com/PennyLaneAI/pennylane/pull/5684)
+  [(#5718)](https://github.com/PennyLaneAI/pennylane/pull/5718)
 
+  ```pycon
+  >>> fcond1 = qml.noise.op_eq(qml.RX) & qml.noise.wires_in([0, 1])
+  >>> noise1 = qml.noise.partial_wires(qml.PhaseDamping, 0.4)
+  >>> fcond2 = qml.noise.op_in([qml.RY, qml.RZ])
+  >>> def noise2(op, **kwargs):
+  ...     qml.ThermalRelaxationError(op.parameters[0] * 0.05, kwargs["t1"], 0.2, 0.6, op.wires)
+  >>> noise_model = qml.NoiseModel({fcond1: noise1, fcond2: noise2}, t1=2.0)
+  >>> noise_model
+  NoiseModel({
+      OpEq(RX) & WiresIn([0, 1]) = PhaseDamping(gamma=0.4)
+      OpIn(['RY', 'RZ']) = noise2
+  }, t1 = 2.0)
   ```
+
   ```pycon
-  >>> print(pl_op)
-  a⁺(0) a(2)
+  >>> @partial(qml.transforms.add_noise, noise_model=noise_model)
+  ... @qml.qnode(dev)
+  ... def circuit(w, x, y, z):
+  ...    qml.RX(w, wires=0)
+  ...    qml.RY(x, wires=1)
+  ...    qml.CNOT(wires=[0, 1])
+  ...    qml.RY(y, wires=0)
+  ...    qml.RX(z, wires=1)
+  ...    return qml.expval(qml.Z(0) @ qml.Z(1))
+  >>> print(qml.draw(circuit)(0.9, 0.4, 0.5, 0.6))
+  0: ──RX(0.90)──PhaseDamping(0.40)──────────────────────────╭●──RY(0.50)
+  1: ──RY(0.40)──ThermalRelaxationError(0.02,2.00,0.20,0.60)─╰X──RX(0.60)
+  ───ThermalRelaxationError(0.03,2.00,0.20,0.60)─┤ ╭<Z@Z>
+  ───PhaseDamping(0.40)──────────────────────────┤ ╰<Z@Z>
   ```
 
-* A new `qml.noise` module which contains utililty functions for building `NoiseModels`.
-  [(#5674)](https://github.com/PennyLaneAI/pennylane/pull/5674)
-  [(#5684)](https://github.com/PennyLaneAI/pennylane/pull/5684)
+* The ``from_openfermion`` and ``to_openfermion`` functions are added to convert between 
+  OpenFermion and PennyLane objects.
+  [(#5773)](https://github.com/PennyLaneAI/pennylane/pull/5773)
+  [(#5808)](https://github.com/PennyLaneAI/pennylane/pull/5808)
 
   ```python
-  fcond = qml.noise.op_eq(qml.X) | qml.noise.op_eq(qml.Y)
-  noise = qml.noise.partial_wires(qml.AmplitudeDamping, 0.4)
+  of_op = openfermion.FermionOperator('0^ 2')
+  pl_op = qml.from_openfermion(of_op)
+  of_op_new = qml.to_openfermion(pl_op)
   ```
 
   ```pycon
-  >>> qml.NoiseModel({fcond: noise}, t1=0.04)
-  NoiseModel({
-    OpEq(PauliX) | OpEq(PauliY) = AmplitudeDamping(gamma=0.4)
-  }, t1 = 0.04)
+  >>> print(pl_op)
+  a⁺(0) a(2)
+  >>> print(of_op_new)
+  1.0 [0^ 2]
   ```
 
 <h3>Improvements 🛠</h3>
@@ -230,6 +255,7 @@
 
 * Sets up the framework for the development of an `assert_equal` function for testing operator comparison.
   [(#5634)](https://github.com/PennyLaneAI/pennylane/pull/5634)
+  [(#5858)](https://github.com/PennyLaneAI/pennylane/pull/5858)
 
 * `qml.sample` can now be used on Boolean values representing mid-circuit measurement results in
   traced quantum functions. This feature is used with Catalyst to enable the pattern
@@ -291,12 +317,20 @@
 * `specs()` can now be requested at any specific point of the transform program through the `level` keyword argument.
   [(#5781)](https://github.com/PennyLaneAI/pennylane/pull/5781/)
 
+* The `qml.snapshots` transform now supports arbitrary devices by running a separate tape for each snapshot for unsupported devices.
+  [(#5805)](https://github.com/PennyLaneAI/pennylane/pull/5805)
+
+* The `qml.Snapshot` operator now accepts sample-based measurements for finite-shot devices.
+  [(#5805)](https://github.com/PennyLaneAI/pennylane/pull/5805)
 * Device preprocess transforms now happen inside the ml boundary.
   [(#5791)](https://github.com/PennyLaneAI/pennylane/pull/5791)
 
 * `qml.qchem.molecular_dipole` function is added for calculating the dipole operator using "dhf" and "openfermion" backends.
   [(#5764)](https://github.com/PennyLaneAI/pennylane/pull/5764)
 
+* Circuits can now be plotted at any specific point of the transform program through the `level` keyword argument in `draw()` and `draw_mpl()`.
+  [(#5855)](https://github.com/PennyLaneAI/pennylane/pull/5855)
+
 * Transforms applied to callables now use `functools.wraps` to preserve the docstring and call signature of the original function.
   [(#5857)](https://github.com/PennyLaneAI/pennylane/pull/5857)
 
@@ -309,7 +343,8 @@
   [(#5502)](https://github.com/PennyLaneAI/pennylane/pull/5502)
 
 * Implement support in `assert_equal` for `Operator`, `Controlled`, `Adjoint`, `Pow`, `Exp`, `SProd`, `ControlledSequence`, `Prod`, `Sum`, `Tensor` and `Hamiltonian`
- [(#5780)](https://github.com/PennyLaneAI/pennylane/pull/5780)
+  [(#5780)](https://github.com/PennyLaneAI/pennylane/pull/5780)
+  [(#5877)](https://github.com/PennyLaneAI/pennylane/pull/5877)
 
 * `qml.QutritChannel` has been added, enabling the specification of noise using a collection of (3x3) Kraus matrices on the `default.qutrit.mixed` device.
   [(#5793)](https://github.com/PennyLaneAI/pennylane/issues/5793)
@@ -472,6 +507,15 @@
 * `qml.matrix` is now compatible with qnodes compiled by catalyst.qjit.
   [(#5753)](https://github.com/PennyLaneAI/pennylane/pull/5753)
 
+* `qml.snapshots` raises an error when a measurement other than `qml.state` is requested from `default.qubit.legacy` instead of silently returning the statevector.
+  [(#5805)](https://github.com/PennyLaneAI/pennylane/pull/5805)
+
+* Fixes a bug where `default.qutrit` is falsely determined to be natively compatible with `qml.snapshots`.
+  [(#5805)](https://github.com/PennyLaneAI/pennylane/pull/5805)
+
+* Fixes a bug where the measurement of a `qml.Snapshot` instance is not passed on during the `qml.adjoint` and `qml.ctrl` operations.
+  [(#5805)](https://github.com/PennyLaneAI/pennylane/pull/5805)
+
 * `CNOT` and `Toffoli` now have an `arithmetic_depth` of `1`, as they are controlled operations.
   [(#5797)](https://github.com/PennyLaneAI/pennylane/pull/5797)
 
@@ -487,6 +531,9 @@
 * Fix bug where `CompositeOp.overlapping_ops` sometimes puts overlapping ops in different groups, leading to incorrect results returned by `LinearCombination.eigvals()`
   [(#5847)](https://github.com/PennyLaneAI/pennylane/pull/5847)
 
+* `qml.pauli_decompose` now works in a jit-ted context, such as `jax.jit` and `catalyst.qjit`.
+  [(#5878)](https://github.com/PennyLaneAI/pennylane/pull/5878)
+
 <h3>Contributors ✍️</h3>
 
 This release contains contributions from (in alphabetical order):
@@ -503,6 +550,7 @@ Isaac De Vlugt,
 Diksha Dhawan,
 Pietropaolo Frisoni,
 Emiliano Godinez,
+Daria Van Hende,
 Austin Huang,
 David Ittah,
 Soran Jahangiri,

pennylane/__init__.py

@@ -51,6 +51,7 @@
     taper_operation,
     import_operator,
     from_openfermion,
+    to_openfermion,
 )
 from pennylane._device import Device, DeviceError
 from pennylane._grad import grad, jacobian, vjp, jvp
@@ -104,11 +105,13 @@
     pattern_matching,
     pattern_matching_optimization,
     clifford_t_decomposition,
+    add_noise,
 )
 from pennylane.ops.functions import (
     dot,
     eigvals,
     equal,
+    assert_equal,
     evolve,
     generator,
     is_commuting,