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 r6771895 = R;
        double r6771896 = 2.0;
        double r6771897 = phi1;
        double r6771898 = phi2;
        double r6771899 = r6771897 - r6771898;
        double r6771900 = r6771899 / r6771896;
        double r6771901 = sin(r6771900);
        double r6771902 = pow(r6771901, r6771896);
        double r6771903 = cos(r6771897);
        double r6771904 = cos(r6771898);
        double r6771905 = r6771903 * r6771904;
        double r6771906 = lambda1;
        double r6771907 = lambda2;
        double r6771908 = r6771906 - r6771907;
        double r6771909 = r6771908 / r6771896;
        double r6771910 = sin(r6771909);
        double r6771911 = r6771905 * r6771910;
        double r6771912 = r6771911 * r6771910;
        double r6771913 = r6771902 + r6771912;
        double r6771914 = sqrt(r6771913);
        double r6771915 = 1.0;
        double r6771916 = r6771915 - r6771913;
        double r6771917 = sqrt(r6771916);
        double r6771918 = atan2(r6771914, r6771917);
        double r6771919 = r6771896 * r6771918;
        double r6771920 = r6771895 * r6771919;
        return r6771920;
}