\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)\pi \cdot \ell - \frac{1}{\frac{F}{\tan \left(\pi \cdot \ell\right)}} \cdot \frac{1}{F}double f(double F, double l) {
double r17398 = atan2(1.0, 0.0);
double r17399 = l;
double r17400 = r17398 * r17399;
double r17401 = 1.0;
double r17402 = F;
double r17403 = r17402 * r17402;
double r17404 = r17401 / r17403;
double r17405 = tan(r17400);
double r17406 = r17404 * r17405;
double r17407 = r17400 - r17406;
return r17407;
}
double f(double F, double l) {
double r17408 = atan2(1.0, 0.0);
double r17409 = l;
double r17410 = r17408 * r17409;
double r17411 = 1.0;
double r17412 = F;
double r17413 = tan(r17410);
double r17414 = r17412 / r17413;
double r17415 = r17411 / r17414;
double r17416 = 1.0;
double r17417 = r17416 / r17412;
double r17418 = r17415 * r17417;
double r17419 = r17410 - r17418;
return r17419;
}



Bits error versus F



Bits error versus l
Results
Initial program 16.5
rmApplied add-cube-cbrt16.5
Applied times-frac16.6
Applied associate-*l*12.5
rmApplied associate-*l/12.5
rmApplied div-inv12.5
Applied associate-*r*12.5
Simplified12.5
Final simplification12.5
herbie shell --seed 2019347
(FPCore (F l)
:name "VandenBroeck and Keller, Equation (6)"
:precision binary64
(- (* PI l) (* (/ 1 (* F F)) (tan (* PI l)))))