\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 r25044 = atan2(1.0, 0.0);
double r25045 = l;
double r25046 = r25044 * r25045;
double r25047 = 1.0;
double r25048 = F;
double r25049 = r25048 * r25048;
double r25050 = r25047 / r25049;
double r25051 = tan(r25046);
double r25052 = r25050 * r25051;
double r25053 = r25046 - r25052;
return r25053;
}
double f(double F, double l) {
double r25054 = atan2(1.0, 0.0);
double r25055 = l;
double r25056 = r25054 * r25055;
double r25057 = 1.0;
double r25058 = sqrt(r25057);
double r25059 = F;
double r25060 = r25058 / r25059;
double r25061 = sqrt(r25054);
double r25062 = sqrt(r25061);
double r25063 = r25062 * r25062;
double r25064 = r25063 * r25055;
double r25065 = r25061 * r25064;
double r25066 = tan(r25065);
double r25067 = r25060 * r25066;
double r25068 = r25060 * r25067;
double r25069 = r25056 - r25068;
return r25069;
}



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 +o rules:numerics
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))