\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)\pi \cdot \ell - \frac{1}{F} \cdot \left(\frac{\sqrt{1}}{\sqrt[3]{F} \cdot \sqrt[3]{F}} \cdot \left(\frac{\sqrt{1}}{\sqrt[3]{F}} \cdot \tan \left(\pi \cdot \ell\right)\right)\right)double f(double F, double l) {
double r17986 = atan2(1.0, 0.0);
double r17987 = l;
double r17988 = r17986 * r17987;
double r17989 = 1.0;
double r17990 = F;
double r17991 = r17990 * r17990;
double r17992 = r17989 / r17991;
double r17993 = tan(r17988);
double r17994 = r17992 * r17993;
double r17995 = r17988 - r17994;
return r17995;
}
double f(double F, double l) {
double r17996 = atan2(1.0, 0.0);
double r17997 = l;
double r17998 = r17996 * r17997;
double r17999 = 1.0;
double r18000 = F;
double r18001 = r17999 / r18000;
double r18002 = 1.0;
double r18003 = sqrt(r18002);
double r18004 = cbrt(r18000);
double r18005 = r18004 * r18004;
double r18006 = r18003 / r18005;
double r18007 = r18003 / r18004;
double r18008 = tan(r17998);
double r18009 = r18007 * r18008;
double r18010 = r18006 * r18009;
double r18011 = r18001 * r18010;
double r18012 = r17998 - r18011;
return r18012;
}



Bits error versus F



Bits error versus l
Results
Initial program 16.5
rmApplied *-un-lft-identity16.5
Applied times-frac16.5
Applied associate-*l*12.3
rmApplied add-cube-cbrt12.5
Applied add-sqr-sqrt12.5
Applied times-frac12.5
Applied associate-*l*12.5
Final simplification12.5
herbie shell --seed 2020057 +o rules:numerics
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))