\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)\pi \cdot \ell - \frac{\sqrt{1}}{F} \cdot \left(\frac{\sqrt{1}}{F} \cdot \tan \left(\sqrt{\sqrt{\pi}} \cdot \left(\sqrt{\sqrt{\pi}} \cdot \left(\sqrt{\pi} \cdot \ell\right)\right)\right)\right)double f(double F, double l) {
double r14775 = atan2(1.0, 0.0);
double r14776 = l;
double r14777 = r14775 * r14776;
double r14778 = 1.0;
double r14779 = F;
double r14780 = r14779 * r14779;
double r14781 = r14778 / r14780;
double r14782 = tan(r14777);
double r14783 = r14781 * r14782;
double r14784 = r14777 - r14783;
return r14784;
}
double f(double F, double l) {
double r14785 = atan2(1.0, 0.0);
double r14786 = l;
double r14787 = r14785 * r14786;
double r14788 = 1.0;
double r14789 = sqrt(r14788);
double r14790 = F;
double r14791 = r14789 / r14790;
double r14792 = sqrt(r14785);
double r14793 = sqrt(r14792);
double r14794 = r14792 * r14786;
double r14795 = r14793 * r14794;
double r14796 = r14793 * r14795;
double r14797 = tan(r14796);
double r14798 = r14791 * r14797;
double r14799 = r14791 * r14798;
double r14800 = r14787 - r14799;
return r14800;
}



Bits error versus F



Bits error versus l
Results
Initial program 17.5
rmApplied add-sqr-sqrt17.5
Applied times-frac17.5
Applied associate-*l*13.0
rmApplied add-sqr-sqrt13.1
Applied associate-*l*13.1
rmApplied add-sqr-sqrt13.1
Applied sqrt-prod13.0
Applied associate-*l*13.0
Final simplification13.0
herbie shell --seed 2020056
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))