Add MCM bindings and tests for L-Kokkos.

[vincentmr]

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---

Context:

Description of the Change:

Benefits:

Possible Drawbacks:

Related GitHub Issues:
[sc-60946]

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.70%. Comparing base (30e51b9) to head (008ac80).
Report is 1 commits behind head on feature/mid-measure-kokkos.

Additional details and impacted files

@@                      Coverage Diff                       @@
##           feature/mid-measure-kokkos     #672      +/-   ##
==============================================================
+ Coverage                       98.65%   98.70%   +0.04%     
==============================================================
  Files                             172      172              
  Lines                           24458    24475      +17     
==============================================================
+ Hits                            24128    24157      +29     
+ Misses                            330      318      -12     

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[tomlqc]

I've tried to run this:

import numpy as np
import pennylane as qml

dev = qml.device("lightning.kokkos", wires=3)

@qml.qnode(dev)
def circuit(x, y):
    qml.RY(x, wires=0)
    qml.CNOT(wires=[0, 1])
    m_0 = qml.measure(1)

    qml.cond(m_0, qml.RY)(y, wires=0)
    return qml.probs(wires=[0])

circuit(np.pi/2, np.pi/4)

I got

Traceback (most recent call last):
  File "/home/thomas.germain/PennyLane/pennylane-lightning/debug.py", line 20, in <module>
    circuit(np.pi/2, np.pi/4)
  File "/home/thomas.germain/PennyLane/pennylane/pennylane/workflow/qnode.py", line 1085, in __call__
    res = self._execution_component(args, kwargs, override_shots=override_shots)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/thomas.germain/PennyLane/pennylane/pennylane/workflow/qnode.py", line 1039, in _execution_component
    res = qml.execute(
          ^^^^^^^^^^^^
  File "/home/thomas.germain/PennyLane/pennylane/pennylane/workflow/execution.py", line 603, in execute
    tapes, program_post_processing = transform_program(tapes)
                                     ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/thomas.germain/PennyLane/pennylane/pennylane/transforms/core/transform_program.py", line 509, in __call__
    new_tapes, fn = transform(tape, *targs, **tkwargs)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/thomas.germain/PennyLane/pennylane/pennylane/transforms/dynamic_one_shot.py", line 94, in dynamic_one_shot
    output_tapes = [aux_tape] * tape.shots.total_shots
                   ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
TypeError: can't multiply sequence by non-int of type 'NoneType'

Have I done something wrong in my setup? (The C++ tests run successfully.)

[tomlqc]

A more general question: Why are lightning_qubit.py and lightning_kokkos.py so different? Is it because only LQ is on the new dev API or did we have such big differences before too?

[vincentmr]

Have I done something wrong in my setup? (The C++ tests run successfully.)

Looks like PennyLane might not be the right version.

[vincentmr]

A more general question: Why are lightning_qubit.py and lightning_kokkos.py so different? Is it because only LQ is on the new dev API or did we have such big differences before too?

That's right, it is an old/new API difference.