Cannot sample enough valid points. (more)

\[R \cdot \left(2 \cdot \tan^{-1}_* \frac{\sqrt{{\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2} + \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)}}{\sqrt{1 - \left({\left(\sin \left(\frac{\phi_1 - \phi_2}{2}\right)\right)}^{2} + \left(\left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right) \cdot \sin \left(\frac{\lambda_1 - \lambda_2}{2}\right)\right)}}\right)\]
R \cdot \left(2 \cdot \tan^{-1}_* \frac{\sqrt{{\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)
double f(double R, double lambda1, double lambda2, double phi1, double phi2) {
        double r2605221 = R;
        double r2605222 = 2.0;
        double r2605223 = phi1;
        double r2605224 = phi2;
        double r2605225 = r2605223 - r2605224;
        double r2605226 = r2605225 / r2605222;
        double r2605227 = sin(r2605226);
        double r2605228 = pow(r2605227, r2605222);
        double r2605229 = cos(r2605223);
        double r2605230 = cos(r2605224);
        double r2605231 = r2605229 * r2605230;
        double r2605232 = lambda1;
        double r2605233 = lambda2;
        double r2605234 = r2605232 - r2605233;
        double r2605235 = r2605234 / r2605222;
        double r2605236 = sin(r2605235);
        double r2605237 = r2605231 * r2605236;
        double r2605238 = r2605237 * r2605236;
        double r2605239 = r2605228 + r2605238;
        double r2605240 = sqrt(r2605239);
        double r2605241 = 1.0;
        double r2605242 = r2605241 - r2605239;
        double r2605243 = sqrt(r2605242);
        double r2605244 = atan2(r2605240, r2605243);
        double r2605245 = r2605222 * r2605244;
        double r2605246 = r2605221 * r2605245;
        return r2605246;
}