MQLib.jl

MQLib wrapper for JuMP.

MQLib.jl uses the libmqlib_c_api shared-library product provided by MQLib_jll v0.1.2 and newer. The executable-backed path remains as a defensive fallback if the library product is unavailable, or if a default hyperheuristic solve needs model files that are not packaged in the JLL.

Installation

julia> import Pkg

julia> Pkg.add("MQLib")

Basic Usage

using JuMP, MQLib

Q = [
   -1  2  2
    2 -1  2
    2  2 -1
]

model = Model(MQLib.Optimizer)

@variable(model, x[1:3], Bin)
@objective(model, Max, x' * Q * x)

optimize!(model)

Selecting Heuristics

This wrapper allows one to access the QUBO and Max-Cut heuristics provided by MQLib. Selecting the method to be used can be achieved via JuMP's attribute interface:

JuMP.set_optimizer_attribute(model, "heuristic", "ALKHAMIS1998")

or by calling MQLib helper functions:

MQLib.set_heuristic(model, "ALKHAMIS1998")

To list available heuristics and their descriptions, run:

MQLib.show_heuristics()

Reads, Seeds, and Time Limits

MQLib.jl supports the standard QUBODrivers.RandomSeed() attribute through the raw "seed" optimizer attribute. QUBODrivers.FinalNumberOfReads() controls the number of emitted samples; when it is unset, it falls back to "num_reads".

MOI.TimeLimitSec() is divided evenly across the emitted reads and passed to MQLib as the per-heuristic runtime limit. If no time limit is set, each read uses a one-second total default split across the requested reads.