\left(J \cdot \left(e^{\ell} - e^{-\ell}\right)\right) \cdot \cos \left(\frac{K}{2}\right) + U\left(2 \cdot \sinh \ell\right) \cdot \left(J \cdot \cos \left(K \cdot 0.5\right)\right) + U
(FPCore (J l K U) :precision binary64 (+ (* (* J (- (exp l) (exp (- l)))) (cos (/ K 2.0))) U))
(FPCore (J l K U) :precision binary64 (+ (* (* 2.0 (sinh l)) (* J (cos (* K 0.5)))) U))
double code(double J, double l, double K, double U) {
return ((J * (exp(l) - exp(-l))) * cos(K / 2.0)) + U;
}
double code(double J, double l, double K, double U) {
return ((2.0 * sinh(l)) * (J * cos(K * 0.5))) + U;
}



Bits error versus J



Bits error versus l



Bits error versus K



Bits error versus U
Results
Initial program 17.7
Taylor expanded around inf 17.7
Simplified0.1
Final simplification0.1
herbie shell --seed 2020231
(FPCore (J l K U)
:name "Maksimov and Kolovsky, Equation (4)"
:precision binary64
(+ (* (* J (- (exp l) (exp (- l)))) (cos (/ K 2.0))) U))