Function optimize_fusion 

pub fn optimize_fusion<K: Clone + Eq + Hash>(
    qrels: &Qrels<K>,
    runs: &[Vec<(K, f32)>],
    config: OptimizeConfig,
) -> OptimizedParams

Optimize fusion hyperparameters using grid search.

Given relevance judgments (qrels) and multiple retrieval runs, searches over parameter space to find the best configuration.

Example

use rankops::optimize::{optimize_fusion, OptimizeConfig, OptimizeMetric, ParamGrid};
use rankops::FusionMethod;

let qrels = std::collections::HashMap::from([
    ("doc1", 2), // highly relevant
    ("doc2", 1), // relevant
]);

let runs = vec![
    vec![("doc1", 0.9), ("doc2", 0.8)],
    vec![("doc2", 0.9), ("doc1", 0.7)],
];

let config = OptimizeConfig {
    method: FusionMethod::Rrf { k: 60 }, // will be overridden
    metric: OptimizeMetric::Ndcg { k: 10 },
    param_grid: ParamGrid::RrfK {
        values: vec![20, 40, 60, 100],
    },
};

let optimized = optimize_fusion(&qrels, &runs, config);
println!("Best k: {}, score: {:.4}", optimized.best_params, optimized.best_score);