MIRPLib.jl

This package reads data files for Maritime Inventory Routing Problem (MIRP) instances from MIRPLib.

Research Context

This package is part of the research artifacts accompanying the paper:

Sanghikian, N., Meirelles, R., Subramanian, A., Martinelli, R.
A heuristic algorithm based on beam search and iterated local search for the maritime inventory routing problem.
Computers & Operations Research, 188 (2026), 107347.

The package provides the data structures and instance-loading utilities used in the computational experiments on MIRPLib Group 2 instances, enabling reproducibility and further methodological extensions.

Usage

The main type returned by the package is MIRP, defined as follows:

struct MIRP
    name::String
    type::Symbol
    metadata::Metadata

    ports::Vector{Port}
    load_ports::Vector{Port}
    unload_ports::Vector{Port}

    classes::Vector{Class}
    vessels::Vector{Vessel}

    distances::Matrix{Float64}

    lb::Float64
    ub::Float64
end

Metadata, ports, vessel classes, and vessels are defined as follows:

struct Metadata
    n_periods::Int64
    n_commodities::Int64

    n_ports::Int64
    n_ports_per_region::Vector{Int64}

    n_load_regions::Int64
    n_unload_regions::Int64
    n_ports_per_load_region::Vector{Int64}
    n_ports_per_unload_region::Vector{Int64}

    n_vessels::Int64
    n_vessel_classes::Int64
    n_vessels_per_class::Vector{Int64}

    hours_per_period::Float64
    spot_market_price::Float64
    spot_market_discount::Float64
    attempt_cost::Float64
    reward_finishing_early::Float64
    single_period_alpha_slack::Float64
    cumulative_alpha_slack::Float64
end

struct Port
    id::Int64
    name::String
    type::Symbol
    region_id::Int64
    x::Float64
    y::Float64
    fee::Float64
    berth_limit::Int64
    max_amt::Int64
    min_amt::Int64
    capacity::Int64
    inventory::Int64
    rates::Vector{Int64}
    prices::Vector{Float64}
end

struct Class
    id::Int64
    name::String
    capacity::Int64
    speed::Float64
    travel_cost_km::Float64
    discount_empty::Float64
    vessels::Vector{Vessel}
    travel_times::Matrix{Int64}
end

struct Vessel
    id::Int64
    name::String
    class::Class
    inventory::Int64
    initial_port::Port
    first_time::Int64
end

Some MIRPLib instances are preloaded in Instance. For example:

using MIRPLib

mirp = loadMIRP(:LR1_1_DR1_3_VC1_V7a, 60)
println(mirp)

loadMIRP returns nothing if the instance is not found. The MIRPLib zip file is kept under data/ and downloaded automatically if it is missing.

If you wish to get a list of all instances, use Instance enum.

all_instances = instances(Instance)

Installation

MIRPLib.jl is a registered Julia Package! yay!

You can install MIRPLib.jl through the Julia package manager.

Open Julia's interactive session (REPL) and type:

] add MIRPLib

Do not forget to ⭐star⭐ our package! 😁

Related links

• Georgia Tech's MIRPLib Page

Citation

This package implements and supports the data layer used in the computational study of the paper below. If you use MIRPLib.jl, please cite:

@article{Sanghikian2026MIRP,
  title = {A heuristic algorithm based on beam search and iterated local search for the maritime inventory routing problem},
  author = {Sanghikian, Nathalie and Meirelles, Rafael and Subramanian, Anand and Martinelli, Rafael},
  journal = {Computers \& Operations Research},
  year = {2026},
  volume = {188},
  pages = {107347},
  doi = {10.1016/j.cor.2025.107347},
  url = {https://www.sciencedirect.com/science/article/pii/S0305054825003764}
}

The same entry is in CITATION.bib.

Other packages

• InventoryRoutingProblems.jl: Inventory Routing Problem (IRP) Julia package
• Knapsacks.jl: Knapsack algorithms in Julia
• FacilityLocationProblems.jl: Facility Location Problems Lib
• AssignmentProblems.jl: Assignment Problems Lib
• BPPLib.jl: Bin Packing and Cutting Stock Problems Lib
• CARPData.jl: Capacitated Arc Routing Problem Lib
• MDVSP.jl: Multiple-Depot Vehicle Scheduling Problem Lib
• CVRPLIB.jl: Capacitated Vehicle Routing Problem Lib
• TSPLIB.jl: Traveling Salesman Problem Lib

License

MIT License. See LICENSE.