Add mcmc sampler

[trevor-vincent]

No description provided.

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[mlxd]

Just a quick one for the failures. Will do a more in-depth review later.

[codecov]

Codecov Report

Merging #384 (f51d1d5) into master (08dfbe0) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff            @@
##           master     #384    +/-   ##
========================================
  Coverage   99.82%   99.82%            
========================================
  Files          49       50     +1     
  Lines        4517     4624   +107     
========================================
+ Hits         4509     4616   +107     
  Misses          8        8            

Impacted Files	Coverage Δ
pennylane_lightning/_version.py	100.00% <100.00%> (ø)
pennylane_lightning/lightning_qubit.py	99.10% <100.00%> (+0.02%)	⬆️
pennylane_lightning/src/simulator/Measures.hpp	99.52% <100.00%> (+0.14%)	⬆️
...lane_lightning/src/simulator/TransitionKernels.hpp	100.00% <100.00%> (ø)

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[mlxd]

Thanks @trevor-vincent
Some suggestions regarding the test coverage. Also, can we add a docstring to each class and associated method?

[trbromley]

Thanks @multiphaseCFD @trevor-vincent!

This looks great! How will a PL user enable the MCMC sampling mode? Aside from directly calling the device methods (which may not be known to non-expert users), it would be nice for users to be able to opt-in to MCMC sampling easily. For example, when instantiating the device qml.device("lightning.qubit", shots=100, mcmc=True) - though I'm curious if there has been any prior discussion on this?

[multiphaseCFD]

Thanks @multiphaseCFD @trevor-vincent!

This looks great! How will a PL user enable the MCMC sampling mode? Aside from directly calling the device methods (which may not be known to non-expert users), it would be nice for users to be able to opt-in to MCMC sampling easily. For example, when instantiating the device qml.device("lightning.qubit", shots=100, mcmc=True) - though I'm curious if there has been any prior discussion on this?

Hi @trbromley , That's a good point! We didn't discuss that before. Let me discuss with @mlxd , then get back to you.

[mlxd]

Nothing more from me --- thanks for the work everybody!

[vincentmr]

Just made a couple suggestions. Happy to approve!

Outdated from Nov 2022

[trbromley]

Thanks @multiphaseCFD! I've left a few suggestions on the documentation side, but otherwise looks great to me!