\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{\pi} \cdot \left(\left(\sqrt{\sqrt{\pi}} \cdot \sqrt{\sqrt{\pi}}\right) \cdot \ell\right)\right)\right)double f(double F, double l) {
double r23792 = atan2(1.0, 0.0);
double r23793 = l;
double r23794 = r23792 * r23793;
double r23795 = 1.0;
double r23796 = F;
double r23797 = r23796 * r23796;
double r23798 = r23795 / r23797;
double r23799 = tan(r23794);
double r23800 = r23798 * r23799;
double r23801 = r23794 - r23800;
return r23801;
}
double f(double F, double l) {
double r23802 = atan2(1.0, 0.0);
double r23803 = l;
double r23804 = r23802 * r23803;
double r23805 = 1.0;
double r23806 = sqrt(r23805);
double r23807 = F;
double r23808 = r23806 / r23807;
double r23809 = sqrt(r23802);
double r23810 = sqrt(r23809);
double r23811 = r23810 * r23810;
double r23812 = r23811 * r23803;
double r23813 = r23809 * r23812;
double r23814 = tan(r23813);
double r23815 = r23808 * r23814;
double r23816 = r23808 * r23815;
double r23817 = r23804 - r23816;
return r23817;
}



Bits error versus F



Bits error versus l
Results
Initial program 16.9
rmApplied add-sqr-sqrt16.9
Applied times-frac16.9
Applied associate-*l*12.5
rmApplied add-sqr-sqrt12.6
Applied associate-*l*12.6
rmApplied add-sqr-sqrt12.6
Applied sqrt-prod12.5
Final simplification12.5
herbie shell --seed 2019303
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))