reverse annealing for solutions obtained with LeapHybridSampler()

Hi all,

I am trying to get local improvements to a solution of a bqm I obtained via LeapHybridSampler(). I have the reverse annealing example you kindly provided as a guide and I am following the steps of the tutorial. I would like to do something like

sampler_reverse = ReverseAdvanceComposite(sampler)

solution= sampler_reverse.sample(bqm,

Is this correct? I would like to provide the binary values of the solution as initial_state. In order to do so I  define a dictionary containing the value of the binary variables (casted as 'int8') resulting as a solution.

If I try to define as forwardSampler the LeapHybridSampler() I used before, I get the error


Connected to sampler hybrid_binary_quadratic_model_version2
Traceback (most recent call last):
print("Maximum anneal-schedule points: {}".format(["max_anneal_schedule_points"]))
KeyError: 'max_anneal_schedule_points'


Does this mean that the LeapHybridSampler() cannot be used to define reverse_anneal samplers?

Otherwise if I define DwaveSampler() as forward sampler I obtain 


Connected to sampler Advantage_system4.1
Maximum anneal-schedule points: 12
Annealing time range: [0.5, 2000.0]
Maximum slope allowed on this solver is 2.00.
Traceback (most recent call last):
raise BinaryQuadraticModelStructureError(msg)
dimod.exceptions.BinaryQuadraticModelStructureError: Problem graph incompatible with solver.


Thank you in advance for all the help.

Kind regards.



  • Dear all,

    ok, I have read the documentation and for the first error, I have understood that I cannot use the LeapHybridSampler(). Is this correct?

    As far as the second question is concerned, I have found a workaround using an appropriate composite that  embeds the dwave sample, and now it partially works.

    But still, I have a question. In the reverse annealing example you provided there are functions like make_reverse_anneal_schedule that are made available via the helpers.schedule module. In the offline dwave python package I downloaded via pip I cannot find it. what package am I supposed to download?

    Thank you very much in advance.

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  • Giuliana,

    To see the supporting code called in the Jupyter Notebook Reverse Annealing example, click on the "File" tab of the Jupyter notebook (not the browser) and then click "open".

    The make_reverse_anneal_schedule function is under the helpers folder in


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  • Hello,

    Thank you for pointing this out.
    We are looking at improving the documentation here to make it a bit clearer.

    Sounds like you were able to resolve the second issue by using EmbeddingComposite or something similar.

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