\tan \left(x + \varepsilon\right) - \tan x
\begin{array}{l}
\mathbf{if}\;\varepsilon \le -3.49173971340657552 \cdot 10^{-152} \lor \neg \left(\varepsilon \le 3.3040955223418242 \cdot 10^{-60}\right):\\
\;\;\;\;\frac{\tan x + \tan \varepsilon}{1 - \left(\tan x \cdot \tan \varepsilon\right) \cdot \left(\tan x \cdot \tan \varepsilon\right)} \cdot \left(1 + \log \left(e^{\tan x \cdot \tan \varepsilon}\right)\right) - \tan x\\
\mathbf{else}:\\
\;\;\;\;x \cdot {\varepsilon}^{2} + \left(\varepsilon + {x}^{2} \cdot \varepsilon\right)\\
\end{array}double f(double x, double eps) {
double r165447 = x;
double r165448 = eps;
double r165449 = r165447 + r165448;
double r165450 = tan(r165449);
double r165451 = tan(r165447);
double r165452 = r165450 - r165451;
return r165452;
}
double f(double x, double eps) {
double r165453 = eps;
double r165454 = -3.4917397134065755e-152;
bool r165455 = r165453 <= r165454;
double r165456 = 3.304095522341824e-60;
bool r165457 = r165453 <= r165456;
double r165458 = !r165457;
bool r165459 = r165455 || r165458;
double r165460 = x;
double r165461 = tan(r165460);
double r165462 = tan(r165453);
double r165463 = r165461 + r165462;
double r165464 = 1.0;
double r165465 = r165461 * r165462;
double r165466 = r165465 * r165465;
double r165467 = r165464 - r165466;
double r165468 = r165463 / r165467;
double r165469 = exp(r165465);
double r165470 = log(r165469);
double r165471 = r165464 + r165470;
double r165472 = r165468 * r165471;
double r165473 = r165472 - r165461;
double r165474 = 2.0;
double r165475 = pow(r165453, r165474);
double r165476 = r165460 * r165475;
double r165477 = pow(r165460, r165474);
double r165478 = r165477 * r165453;
double r165479 = r165453 + r165478;
double r165480 = r165476 + r165479;
double r165481 = r165459 ? r165473 : r165480;
return r165481;
}




Bits error versus x




Bits error versus eps
Results
| Original | 36.8 |
|---|---|
| Target | 15.4 |
| Herbie | 15.9 |
if eps < -3.4917397134065755e-152 or 3.304095522341824e-60 < eps Initial program 31.3
rmApplied tan-sum8.3
rmApplied flip--8.4
Applied associate-/r/8.4
Simplified8.4
rmApplied add-log-exp8.5
if -3.4917397134065755e-152 < eps < 3.304095522341824e-60Initial program 48.4
rmApplied tan-sum48.4
rmApplied flip--48.4
Applied associate-/r/48.4
Simplified48.4
Taylor expanded around 0 31.3
Final simplification15.9
herbie shell --seed 2020065
(FPCore (x eps)
:name "2tan (problem 3.3.2)"
:precision binary64
:herbie-target
(/ (sin eps) (* (cos x) (cos (+ x eps))))
(- (tan (+ x eps)) (tan x)))