R \cdot \left(2 \cdot \tan^{-1}_* \frac{\sqrt{{\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2} + \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)}}{\sqrt{1 - \left({\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2} + \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right)}}\right)R \cdot \left(2 \cdot \tan^{-1}_* \frac{\sqrt{\sin \left(\frac{\lambda_1 - \lambda_2}{2}\right) \cdot \left(\left(\cos \phi_2 \cdot \cos \phi_1\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) + {\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2}}}{\sqrt{1 - \left(\sin \left(\frac{\lambda_1 - \lambda_2}{2}\right) \cdot \left(\left(\cos \phi_2 \cdot \cos \phi_1\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) + {\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2}\right)}}\right)double f(double R, double lambda1, double lambda2, double phi1, double phi2) {
double r3804580 = R;
double r3804581 = 2.0;
double r3804582 = phi1;
double r3804583 = phi2;
double r3804584 = r3804582 - r3804583;
double r3804585 = r3804584 / r3804581;
double r3804586 = sin(r3804585);
double r3804587 = pow(r3804586, r3804581);
double r3804588 = cos(r3804582);
double r3804589 = cos(r3804583);
double r3804590 = r3804588 * r3804589;
double r3804591 = lambda1;
double r3804592 = lambda2;
double r3804593 = r3804591 - r3804592;
double r3804594 = r3804593 / r3804581;
double r3804595 = sin(r3804594);
double r3804596 = r3804590 * r3804595;
double r3804597 = r3804596 * r3804595;
double r3804598 = r3804587 + r3804597;
double r3804599 = sqrt(r3804598);
double r3804600 = 1.0;
double r3804601 = r3804600 - r3804598;
double r3804602 = sqrt(r3804601);
double r3804603 = atan2(r3804599, r3804602);
double r3804604 = r3804581 * r3804603;
double r3804605 = r3804580 * r3804604;
return r3804605;
}
double f(double R, double lambda1, double lambda2, double phi1, double phi2) {
double r3804606 = R;
double r3804607 = 2.0;
double r3804608 = lambda1;
double r3804609 = lambda2;
double r3804610 = r3804608 - r3804609;
double r3804611 = r3804610 / r3804607;
double r3804612 = sin(r3804611);
double r3804613 = phi2;
double r3804614 = cos(r3804613);
double r3804615 = phi1;
double r3804616 = cos(r3804615);
double r3804617 = r3804614 * r3804616;
double r3804618 = r3804617 * r3804612;
double r3804619 = r3804612 * r3804618;
double r3804620 = r3804615 - r3804613;
double r3804621 = r3804620 / r3804607;
double r3804622 = sin(r3804621);
double r3804623 = pow(r3804622, r3804607);
double r3804624 = r3804619 + r3804623;
double r3804625 = sqrt(r3804624);
double r3804626 = 1.0;
double r3804627 = r3804626 - r3804624;
double r3804628 = sqrt(r3804627);
double r3804629 = atan2(r3804625, r3804628);
double r3804630 = r3804607 * r3804629;
double r3804631 = r3804606 * r3804630;
return r3804631;
}



Bits error versus R



Bits error versus lambda1



Bits error versus lambda2



Bits error versus phi1



Bits error versus phi2
Results
Initial program 24.2
Final simplification24.2
herbie shell --seed 2019162 +o rules:numerics
(FPCore (R lambda1 lambda2 phi1 phi2)
:name "Distance on a great circle"
(* R (* 2 (atan2 (sqrt (+ (pow (sin (/ (- phi1 phi2) 2)) 2) (* (* (* (cos phi1) (cos phi2)) (sin (/ (- lambda1 lambda2) 2))) (sin (/ (- lambda1 lambda2) 2))))) (sqrt (- 1 (+ (pow (sin (/ (- phi1 phi2) 2)) 2) (* (* (* (cos phi1) (cos phi2)) (sin (/ (- lambda1 lambda2) 2))) (sin (/ (- lambda1 lambda2) 2))))))))))