Pagmo.NET 1.0.0

Pagmo.NET

Pagmo.NET is a C# wrapper for pagmo2, a C++ library providing high-quality metaheuristic and gradient-based optimization algorithms with multi-island parallel evolution support.

Supported platforms: Windows x64, Linux x64, and macOS (arm64 + x86_64 universal binary) — native runtime libraries are bundled in the package. No additional installation required.

Installation

dotnet add package Pagmo.NET --prerelease

Quickstart

using pagmo;

public sealed class SphereProblem : ManagedProblemBase
{
    public override PairOfDoubleVectors get_bounds() => Bounds(
        new[] { -5.0, -5.0 },
        new[] { 5.0, 5.0 });

    public override DoubleVector fitness(DoubleVector x)
        => Vec(x[0] * x[0] + x[1] * x[1]);

    public override ThreadSafety get_thread_safety() => ThreadSafety.Basic;
}

using IAlgorithm algo = new de(100u);
using var udp = new SphereProblem();
using var isl = island.Create(algo, udp, popSize: 64u, seed: 2u);
isl.evolve(1u);
isl.wait_check();

using var result = isl.get_population();
using var bestX = result.champion_x();
using var bestF = result.champion_f();

Use island.Create(...) for single-island runs and archipelago.push_back_island(...) for multi-island parallel search.

Defining custom problems

Implement IProblem or inherit from ManagedProblemBase. Only two methods are required:

public override DoubleVector fitness(DoubleVector x) { ... }
public override PairOfDoubleVectors get_bounds() { ... }

Optional capabilities — gradients, hessians, batch evaluation, seed hooks, metadata — have safe defaults and can be overridden as needed. ManagedProblemBase includes helpers Vec(...) and Bounds(lower, upper) for concise authoring.

Threading

Thread-safe problems — declare ThreadSafety.Basic and the problem instance is shared across threads directly:

public override ThreadSafety get_thread_safety() => ThreadSafety.Basic;

Non-thread-safe problems that can be cloned — implement IThreadCloneableProblem and override Clone() on ManagedProblemBase. Each island or OS thread receives its own exclusive copy, so the problem never needs to be concurrency-safe:

public override ThreadSafety get_thread_safety() => ThreadSafety.None;

public override IProblem Clone() => new MyProblem(); // fresh independent copy

Problems declaring ThreadSafety.None without a working Clone() are rejected on threaded paths (archipelago.push_back_island, thread_bfe) with a descriptive error.

Runnable examples

dotnet run --project Examples/Examples.Pagmo.NET/Examples.Pagmo.NET.csproj -- all

Scenarios: single, archipelago, policies, maneuver. Add --verbose to print algorithm logs after each scenario.

What's included

FAQ

Why .NET and C#? The .NET ecosystem is underappreciated for scientific computing. C# performance is competitive with C++ for many workloads, and .NET's open-source trajectory makes it a strong foundation for numerical work. Pagmo.NET lets teams use pagmo's optimization power without a Python runtime dependency.

Why SWIG? SWIG handles the repetitive wrapping work across a large API surface. The .i interface file is also a useful starting point for bindings in other languages.

Where's IPOPT? IPOPT is not part of this package — it is EPL-2.0-licensed and kept separate from this MPL-2.0 package. Install the Pagmo.NET.Ipopt package to add it; OptionalSolverAvailability.IsIpoptAvailable reports whether it is present at runtime.

Where's SNOPT7? SNOPT7 is proprietary and cannot be bundled. Users with a SNOPT7 license can build Pagmo.NET from source with SNOPT7 support — see the repository README for instructions.

Is this affiliated with ESA or the pagmo2 team? No — Pagmo.NET is an independent .NET binding, not affiliated with ESA or the pagmo2 developers.

License

Pagmo.NET is licensed under the MPL-2.0. It statically links third-party libraries under their own licenses (pagmo2 and NLopt under the LGPL, Boost under BSL-1.0, Intel oneTBB under Apache-2.0, Eigen3 under MPL-2.0). See THIRD_PARTY_LICENSES.md.

Links

• Source repository
• pagmo2 documentation
• Release notes