Attributes

SamplerAttribute

Abstract supertype for optimizer attributes declared by QUBODrivers samplers.

Attributes generated by QUBODrivers.@setup, such as NumberOfReads, subtype SamplerAttribute and can be used with MOI.get, MOI.set, and MOI.supports.

FinalNumberOfReads()

Generic sampler optimizer attribute for the number of reads used to build the final emitted SampleSet.

NumberOfReads remains the convention for reads used by a sampler's internal search, optimization, or objective evaluations. FinalNumberOfReads separates the number of reads returned to users from those internal evaluations. If the final read count is unset (nothing), the effective final read count defaults to the sampler's raw "num_reads" attribute when that attribute is supported.

Generated optimizers created by QUBODrivers.@setup support this attribute and the raw "final_num_reads" key.

final_number_of_reads(sampler)

Return the effective final read count for sampler.

This is equivalent to MOI.get(sampler, FinalNumberOfReads()) for samplers generated by QUBODrivers.@setup. If "final_num_reads" is unset, the returned value falls back to raw "num_reads" when supported; otherwise it is nothing.

PostSampleCallback()

Generic sampler optimizer attribute for a callback applied after backend sampling and before the final SampleSet is attached to the optimizer.

The raw optimizer attribute key is "post_sample_callback". The callback is called as callback(sampleset, sampler), where sampleset is a copy of the raw backend output and sampler is the optimizer/model context. The callback may mutate the copied sample-set metadata and return nothing, or return a SampleSet to replace the emitted samples. Replacing or changing sample states, values, reads, sense, or domain requires PostSampleTransform to be set to true.

PostSampleTransform()

Generic sampler optimizer attribute controlling whether PostSampleCallback may transform emitted samples.

The raw optimizer attribute key is "post_sample_transform", and the default value is false. When set to true, a post-sample callback may return a replacement SampleSet. QUBODrivers records callback metadata and preserves the raw samples in the emitted solution metadata.

post_sample_callback(sampler)

Return the configured post-sample callback for sampler, or nothing when no callback is configured or the sampler does not support the generic callback attribute.

post_sample_transform(sampler)::Bool

Return whether the configured post-sample callback may transform emitted sample states, values, reads, sense, or domain. Samplers that do not support the generic transform attribute default to false.

RawSamplerAttribute{key}

QUBODrivers raw optimizer attribute identified by a string-like key.

RawSamplerAttribute("num_reads") is the QUBODrivers counterpart of MOI.RawOptimizerAttribute("num_reads"). Generated samplers route MOI raw attributes through this type so solver-specific attributes can share the same storage and validation as typed sampler attributes.

@raw_attr_str("key")

Create a RawSamplerAttribute type for dispatch.

This macro is useful when extending validation for a particular raw attribute:

function MOI.set(sampler::Optimizer, attr::QUBODrivers.@raw_attr_str("seed"), value)
    QUBODrivers.set_raw_attr!(sampler, attr, value)
    return nothing
end

get_raw_attr(sampler, attr)

Return a raw sampler attribute value.

Generated optimizers first look in the sampler's attribute storage and then fall back to default_raw_attr. Most users access this through MOI.get(sampler, MOI.RawOptimizerAttribute(name)) or a typed attribute.

set_raw_attr!(sampler, attr, value)

Store a raw sampler attribute value.

Generated optimizers use this hook from MOI.set. Sampler implementations can specialize it, or specialize MOI.set for a RawSamplerAttribute, to validate backend-specific options before storing them.

default_raw_attr(sampler, attr)

Return the default value for a raw sampler attribute.

Methods are generated by QUBODrivers.@setup for declared attributes. Sampler implementations may add methods to customize defaults for additional raw attributes.