Function ppl_Constraint_coefficient 

pub unsafe extern "C" fn ppl_Constraint_coefficient(
    c: ppl_const_Constraint_t,
    var: ppl_dimension_type,
    n: ppl_Coefficient_t,
) -> c_int

\relates ppl_Constraint_tag \brief Copies into \p n the coefficient of variable \p var in constraint \p c.