math-test-functions 0.5.2

A collection of non linear functions for testing optimisation algorithms
Documentation 
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//! Keanes Bump Constraint2 test function

use ndarray::Array1;

/// Second constraint for Keane's bump function: sum(x_i) <= 7.5*n
/// Returns violation amount (0 if satisfied, positive if violated)
pub fn keanes_bump_constraint2(x: &Array1<f64>) -> f64 {
    let sum: f64 = x.iter().sum();
    let limit = 7.5 * x.len() as f64;
    sum - limit // Constraint: sum <= limit, so violation is sum - limit
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn reports_negative_or_zero_when_sum_is_within_limit() {
        let x = Array1::from(vec![1.0, 2.0, 3.0, 4.0]);
        assert!(keanes_bump_constraint2(&x) <= 0.0);
    }

    #[test]
    fn reports_positive_violation_when_sum_exceeds_limit() {
        let x = Array1::from(vec![10.0, 10.0]);
        assert!(keanes_bump_constraint2(&x) > 0.0);
    }
}