\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\begin{array}{l}
\mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} = -\infty \lor \neg \left(\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \le 1.569821859298618806925582301780582570703 \cdot 10^{303}\right):\\
\;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \frac{\sqrt{\frac{1}{4}} \cdot U}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\\
\mathbf{else}:\\
\;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\\
\end{array}double f(double J, double K, double U) {
double r251654 = -2.0;
double r251655 = J;
double r251656 = r251654 * r251655;
double r251657 = K;
double r251658 = 2.0;
double r251659 = r251657 / r251658;
double r251660 = cos(r251659);
double r251661 = r251656 * r251660;
double r251662 = 1.0;
double r251663 = U;
double r251664 = r251658 * r251655;
double r251665 = r251664 * r251660;
double r251666 = r251663 / r251665;
double r251667 = pow(r251666, r251658);
double r251668 = r251662 + r251667;
double r251669 = sqrt(r251668);
double r251670 = r251661 * r251669;
return r251670;
}
double f(double J, double K, double U) {
double r251671 = -2.0;
double r251672 = J;
double r251673 = r251671 * r251672;
double r251674 = K;
double r251675 = 2.0;
double r251676 = r251674 / r251675;
double r251677 = cos(r251676);
double r251678 = r251673 * r251677;
double r251679 = 1.0;
double r251680 = U;
double r251681 = r251675 * r251672;
double r251682 = r251681 * r251677;
double r251683 = r251680 / r251682;
double r251684 = pow(r251683, r251675);
double r251685 = r251679 + r251684;
double r251686 = sqrt(r251685);
double r251687 = r251678 * r251686;
double r251688 = -inf.0;
bool r251689 = r251687 <= r251688;
double r251690 = 1.5698218592986188e+303;
bool r251691 = r251687 <= r251690;
double r251692 = !r251691;
bool r251693 = r251689 || r251692;
double r251694 = 4.0;
double r251695 = r251679 / r251694;
double r251696 = sqrt(r251695);
double r251697 = r251696 * r251680;
double r251698 = r251679 / r251675;
double r251699 = r251698 * r251674;
double r251700 = cos(r251699);
double r251701 = r251672 * r251700;
double r251702 = r251697 / r251701;
double r251703 = r251678 * r251702;
double r251704 = r251693 ? r251703 : r251687;
return r251704;
}



Bits error versus J



Bits error versus K



Bits error versus U
Results
if (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))) < -inf.0 or 1.5698218592986188e+303 < (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))) Initial program 62.8
Taylor expanded around inf 45.6
Simplified45.6
if -inf.0 < (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))) < 1.5698218592986188e+303Initial program 0.1
Final simplification13.4
herbie shell --seed 2019303
(FPCore (J K U)
:name "Maksimov and Kolovsky, Equation (3)"
:precision binary64
(* (* (* -2 J) (cos (/ K 2))) (sqrt (+ 1 (pow (/ U (* (* 2 J) (cos (/ K 2)))) 2)))))