= -272.08757857240346 * pow(rr, 4) - 1301.9156065646082 * pow(rr, 3) * ss +
670.35710323157377 * pow(rr, 3) - 2118.433312644368 * pow(rr, 2) * pow(ss, 2) +
2366.0424124325496 * pow(rr, 2) * ss - 584.07894350611105 * pow(rr, 2) -
1412.2888750962602 * rr * pow(ss, 3) + 2487.5142099811701 * rr * pow(ss, 2) -
1336.5868478065681 * rr * ss + 209.56769093899996 * rr - 325.47890164116154 * pow(ss, 4) +
788.68080414419887 * pow(ss, 3) - 668.29342390328975 * pow(ss, 2) + 228.60911267703273 * ss -
25.413901799919653