\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)\pi \cdot \ell - 1 \cdot \frac{\frac{\tan \left(\sqrt{\sqrt{\pi}} \cdot \left(\sqrt{\sqrt{\pi}} \cdot \left(\left(\sqrt{\sqrt{\pi}} \cdot \sqrt{\sqrt{\pi}}\right) \cdot \ell\right)\right)\right)}{F}}{F}double f(double F, double l) {
double r20664 = atan2(1.0, 0.0);
double r20665 = l;
double r20666 = r20664 * r20665;
double r20667 = 1.0;
double r20668 = F;
double r20669 = r20668 * r20668;
double r20670 = r20667 / r20669;
double r20671 = tan(r20666);
double r20672 = r20670 * r20671;
double r20673 = r20666 - r20672;
return r20673;
}
double f(double F, double l) {
double r20674 = atan2(1.0, 0.0);
double r20675 = l;
double r20676 = r20674 * r20675;
double r20677 = 1.0;
double r20678 = sqrt(r20674);
double r20679 = sqrt(r20678);
double r20680 = r20679 * r20679;
double r20681 = r20680 * r20675;
double r20682 = r20679 * r20681;
double r20683 = r20679 * r20682;
double r20684 = tan(r20683);
double r20685 = F;
double r20686 = r20684 / r20685;
double r20687 = r20686 / r20685;
double r20688 = r20677 * r20687;
double r20689 = r20676 - r20688;
return r20689;
}



Bits error versus F



Bits error versus l
Results
Initial program 16.1
rmApplied div-inv16.1
Applied associate-*l*16.1
Simplified12.1
rmApplied add-sqr-sqrt12.2
Applied associate-*l*12.2
rmApplied add-sqr-sqrt12.2
Applied sqrt-prod12.1
Applied associate-*l*12.1
rmApplied add-sqr-sqrt12.1
Applied sqrt-prod12.1
Final simplification12.1
herbie shell --seed 2019291
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))