\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sin th\frac{\sin ky}{\mathsf{hypot}\left(\sin ky, \sin kx\right)} \cdot \sin thdouble code(double kx, double ky, double th) {
return ((sin(ky) / sqrt((pow(sin(kx), 2.0) + pow(sin(ky), 2.0)))) * sin(th));
}
double code(double kx, double ky, double th) {
return ((sin(ky) / hypot(sin(ky), sin(kx))) * sin(th));
}



Bits error versus kx



Bits error versus ky



Bits error versus th
Results
Initial program 12.5
Taylor expanded around inf 12.5
Simplified8.9
rmApplied add-sqr-sqrt9.2
Applied *-un-lft-identity9.2
Applied times-frac9.2
rmApplied frac-times9.2
Simplified9.2
Simplified8.9
Final simplification8.9
herbie shell --seed 2020060 +o rules:numerics
(FPCore (kx ky th)
:name "Toniolo and Linder, Equation (3b), real"
:precision binary64
(* (/ (sin ky) (sqrt (+ (pow (sin kx) 2) (pow (sin ky) 2)))) (sin th)))