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 r1968152 = R;
        double r1968153 = 2.0;
        double r1968154 = phi1;
        double r1968155 = phi2;
        double r1968156 = r1968154 - r1968155;
        double r1968157 = r1968156 / r1968153;
        double r1968158 = sin(r1968157);
        double r1968159 = pow(r1968158, r1968153);
        double r1968160 = cos(r1968154);
        double r1968161 = cos(r1968155);
        double r1968162 = r1968160 * r1968161;
        double r1968163 = lambda1;
        double r1968164 = lambda2;
        double r1968165 = r1968163 - r1968164;
        double r1968166 = r1968165 / r1968153;
        double r1968167 = sin(r1968166);
        double r1968168 = r1968162 * r1968167;
        double r1968169 = r1968168 * r1968167;
        double r1968170 = r1968159 + r1968169;
        double r1968171 = sqrt(r1968170);
        double r1968172 = 1.0;
        double r1968173 = r1968172 - r1968170;
        double r1968174 = sqrt(r1968173);
        double r1968175 = atan2(r1968171, r1968174);
        double r1968176 = r1968153 * r1968175;
        double r1968177 = r1968152 * r1968176;
        return r1968177;
}