Class Cluster

crates/openquant/src/hcaa.rs:275–278

fn single_linkage_children(corr: &DMatrix<f64>) -> Vec<[usize; 2]> {
    #[derive(Clone)]
    struct Cluster {
        id: usize,
        members: Vec<usize>,
    }

    let n = corr.nrows();
    let mut distance = DMatrix::zeros(n, n);