Files
Manuel Raimann 47b5f9cec8 feat: unify optimize and optimize_with via blanket Objective impl
- Add blanket `impl Objective<V> for Fn(&mut Trial) -> Result<V, E>`
  so closures work directly with `optimize`
- Rewrite optimize, optimize_async, optimize_parallel to accept
  `impl Objective<V>` with before_trial/after_trial hooks
- Remove optimize_with, optimize_with_async, optimize_with_parallel
- Remove max_retries and retry logic from Objective trait
- Add explicit closure type annotations for HRTB inference
- Convert FnMut test closures to Fn via RefCell/Cell
2026-02-12 13:09:14 +01:00

50 lines
1.5 KiB
Rust

//! Multi-objective optimization — optimize competing objectives simultaneously.
//!
//! `MultiObjectiveStudy` returns the Pareto front: the set of solutions where
//! no objective can be improved without worsening another.
//!
//! Run with: `cargo run --example multi_objective`
use optimizer::multi_objective::MultiObjectiveStudy;
use optimizer::prelude::*;
fn main() -> optimizer::Result<()> {
let study = MultiObjectiveStudy::new(vec![Direction::Minimize, Direction::Minimize]);
let x = FloatParam::new(0.0, 1.0).name("x");
// Classic bi-objective: f1(x) = x², f2(x) = (x-1)²
// The Pareto front is the curve where improving f1 worsens f2.
study.optimize(50, |trial: &mut optimizer::Trial| {
let xv = x.suggest(trial)?;
let f1 = xv * xv;
let f2 = (xv - 1.0) * (xv - 1.0);
Ok::<_, optimizer::Error>(vec![f1, f2])
})?;
let front = study.pareto_front();
println!(
"Ran {} trials, Pareto front has {} solutions:",
study.n_trials(),
front.len(),
);
let mut sorted = front.clone();
sorted.sort_by(|a, b| a.values[0].partial_cmp(&b.values[0]).unwrap());
for (i, trial) in sorted.iter().take(5).enumerate() {
println!(
" {}: x={:.3}, f1={:.4}, f2={:.4}",
i + 1,
trial.get(&x).unwrap(),
trial.values[0],
trial.values[1],
);
}
if sorted.len() > 5 {
println!(" ... and {} more", sorted.len() - 5);
}
Ok(())
}