x + \left(\tan \left(y + z\right) - \tan a\right)
\left(x + \frac{\tan y + \tan z}{1 - \tan y \cdot \tan z}\right) - \tan adouble code(double x, double y, double z, double a) {
return (x + (tan((y + z)) - tan(a)));
}
double code(double x, double y, double z, double a) {
return ((x + ((tan(y) + tan(z)) / (1.0 - (tan(y) * tan(z))))) - tan(a));
}



Bits error versus x



Bits error versus y



Bits error versus z



Bits error versus a
Results
Initial program 12.7
rmApplied tan-sum0.2
rmApplied associate-+r-0.2
Final simplification0.2
herbie shell --seed 2020106 +o rules:numerics
(FPCore (x y z a)
:name "(+ x (- (tan (+ y z)) (tan a)))"
:precision binary64
:pre (and (or (== x 0.0) (<= 0.5884142 x 505.5909)) (or (<= -1.796658e+308 y -9.425585e-310) (<= 1.284938e-309 y 1.7512240000000001e+308)) (or (<= -1.7767070000000002e+308 z -8.599796e-310) (<= 3.293145e-311 z 1.725154e+308)) (or (<= -1.796658e+308 a -9.425585e-310) (<= 1.284938e-309 a 1.7512240000000001e+308)))
(+ x (- (tan (+ y z)) (tan a))))