Function mean_std

crates/openquant/src/feature_importance.rs:369–376

(v: &[f64])

}

fn mean_std(v: &[f64]) -> (f64, f64) {
    if v.is_empty() {
        return (0.0, 0.0);
    }
    let mean = v.iter().sum::<f64>() / v.len() as f64;
    let var = v.iter().map(|x| (x - mean).powi(2)).sum::<f64>() / v.len() as f64;
    (mean, var.sqrt())
}

fn standardize(rows: &[Vec<f64>]) -> Vec<Vec<f64>> {
    let n = rows.len();