dwave.system.composites.ReverseAdvanceComposite.sample#

ReverseAdvanceComposite.sample(bqm, anneal_schedules=None, **parameters)[source]#

Sample the binary quadratic model using reverse annealing along a given set of anneal schedules.

Parameters:

  • bqm (BinaryQuadraticModel) – Binary quadratic model to be sampled from.

  • anneal_schedules (list of lists, optional, default=[[[0, 1], [1, 0.35], [9, 0.35], [10, 1]]]) – Anneal schedules in order of submission. Each schedule is formatted as a list of [time, s] pairs, in which time is in microseconds and s is the normalized persistent current in the range [0,1].

  • initial_state (dict, optional) – The state to reverse anneal from. If not provided, it will be randomly generated.

  • **parameters – Parameters for the sampling method, specified by the child sampler.

Returns:

SampleSet that has initial_state and schedule_index fields.

Examples

This example runs 100 reverse anneals each for three schedules on a problem constructed by setting random \(\pm 1\) values on a clique (complete graph) of 15 nodes, minor-embedded on a D-Wave system using the DWaveCliqueSampler sampler.

>>> import dimod
>>> from dwave.system import DWaveCliqueSampler, ReverseAdvanceComposite
...
>>> sampler = DWaveCliqueSampler()         
>>> sampler_reverse = ReverseAdvanceComposite(sampler)    
>>> schedule = [[[0.0, 1.0], [t, 0.5], [20, 1.0]] for t in (5, 10, 15)]
...
>>> bqm = dimod.generators.ran_r(1, 15)
>>> init_samples = {i: -1 for i in range(15)}
>>> sampleset = sampler_reverse.sample(bqm,
...                                    anneal_schedules=schedule,
...                                    initial_state=init_samples,
...                                    num_reads=100,
...                                    reinitialize_state=True)