Function Z3_rcf_coefficient 

pub unsafe extern "C" fn Z3_rcf_coefficient(
    c: Z3_context,
    a: Z3_rcf_num,
    i: c_uint,
) -> Option<Z3_rcf_num>

Extract a coefficient from an algebraic number.

Preconditions

• Z3_rcf_is_algebraic(ctx, a);