\tan^{-1} \left(N + 1\right) - \tan^{-1} N\tan^{-1}_* \frac{1}{1 + \left(\sqrt[3]{N + 1} \cdot \sqrt[3]{N + 1}\right) \cdot \left(\left(\sqrt[3]{N \cdot N - 1 \cdot 1} \cdot \frac{1}{\sqrt[3]{N - 1}}\right) \cdot N\right)}double f(double N) {
double r119307 = N;
double r119308 = 1.0;
double r119309 = r119307 + r119308;
double r119310 = atan(r119309);
double r119311 = atan(r119307);
double r119312 = r119310 - r119311;
return r119312;
}
double f(double N) {
double r119313 = 1.0;
double r119314 = 1.0;
double r119315 = N;
double r119316 = r119315 + r119313;
double r119317 = cbrt(r119316);
double r119318 = r119317 * r119317;
double r119319 = r119315 * r119315;
double r119320 = r119313 * r119313;
double r119321 = r119319 - r119320;
double r119322 = cbrt(r119321);
double r119323 = r119315 - r119313;
double r119324 = cbrt(r119323);
double r119325 = r119314 / r119324;
double r119326 = r119322 * r119325;
double r119327 = r119326 * r119315;
double r119328 = r119318 * r119327;
double r119329 = r119314 + r119328;
double r119330 = atan2(r119313, r119329);
return r119330;
}




Bits error versus N
Results
| Original | 14.9 |
|---|---|
| Target | 0.3 |
| Herbie | 0.5 |
Initial program 14.9
rmApplied diff-atan13.8
Simplified0.3
rmApplied add-cube-cbrt0.6
Applied associate-*l*0.6
rmApplied flip-+0.6
Applied cbrt-div0.5
rmApplied div-inv0.5
Final simplification0.5
herbie shell --seed 2020047
(FPCore (N)
:name "2atan (example 3.5)"
:precision binary64
:herbie-target
(atan (/ 1 (+ 1 (* N (+ N 1)))))
(- (atan (+ N 1)) (atan N)))