Function check_kkt 

pub fn check_kkt(
    problem: &QpProblem,
    x: &[f64],
    dual: &DualVariables,
) -> Result<KktResiduals, KktError>

Evaluates primal feasibility, stationarity/dual feasibility, and complementarity.

Errors

Returns KktError::Dimension if a primal or multiplier vector has the wrong length.