\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)\pi \cdot \ell - \frac{\sqrt[3]{1} \cdot \sqrt[3]{1}}{F} \cdot \left(\frac{\sqrt[3]{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 r25055 = atan2(1.0, 0.0);
double r25056 = l;
double r25057 = r25055 * r25056;
double r25058 = 1.0;
double r25059 = F;
double r25060 = r25059 * r25059;
double r25061 = r25058 / r25060;
double r25062 = tan(r25057);
double r25063 = r25061 * r25062;
double r25064 = r25057 - r25063;
return r25064;
}
double f(double F, double l) {
double r25065 = atan2(1.0, 0.0);
double r25066 = l;
double r25067 = r25065 * r25066;
double r25068 = 1.0;
double r25069 = cbrt(r25068);
double r25070 = r25069 * r25069;
double r25071 = F;
double r25072 = r25070 / r25071;
double r25073 = r25069 / r25071;
double r25074 = sqrt(r25065);
double r25075 = sqrt(r25074);
double r25076 = r25075 * r25075;
double r25077 = r25076 * r25066;
double r25078 = r25074 * r25077;
double r25079 = tan(r25078);
double r25080 = r25073 * r25079;
double r25081 = r25072 * r25080;
double r25082 = r25067 - r25081;
return r25082;
}



Bits error versus F



Bits error versus l
Results
Initial program 16.9
rmApplied add-cube-cbrt16.9
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)))))