double f(double lambda1, double lambda2, double phi1, double phi2) {
double r2254526 = lambda1;
double r2254527 = lambda2;
double r2254528 = r2254526 - r2254527;
double r2254529 = sin(r2254528);
double r2254530 = phi2;
double r2254531 = cos(r2254530);
double r2254532 = r2254529 * r2254531;
double r2254533 = phi1;
double r2254534 = cos(r2254533);
double r2254535 = sin(r2254530);
double r2254536 = r2254534 * r2254535;
double r2254537 = sin(r2254533);
double r2254538 = r2254537 * r2254531;
double r2254539 = cos(r2254528);
double r2254540 = r2254538 * r2254539;
double r2254541 = r2254536 - r2254540;
double r2254542 = atan2(r2254532, r2254541);
return r2254542;
}