\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 2.060066890954713680905695378128061767254 \cdot 10^{306}\right):\\
\;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \frac{\sqrt{0.25} \cdot U}{J \cdot \cos \left(0.5 \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 r96382 = -2.0;
double r96383 = J;
double r96384 = r96382 * r96383;
double r96385 = K;
double r96386 = 2.0;
double r96387 = r96385 / r96386;
double r96388 = cos(r96387);
double r96389 = r96384 * r96388;
double r96390 = 1.0;
double r96391 = U;
double r96392 = r96386 * r96383;
double r96393 = r96392 * r96388;
double r96394 = r96391 / r96393;
double r96395 = pow(r96394, r96386);
double r96396 = r96390 + r96395;
double r96397 = sqrt(r96396);
double r96398 = r96389 * r96397;
return r96398;
}
double f(double J, double K, double U) {
double r96399 = -2.0;
double r96400 = J;
double r96401 = r96399 * r96400;
double r96402 = K;
double r96403 = 2.0;
double r96404 = r96402 / r96403;
double r96405 = cos(r96404);
double r96406 = r96401 * r96405;
double r96407 = 1.0;
double r96408 = U;
double r96409 = r96403 * r96400;
double r96410 = r96409 * r96405;
double r96411 = r96408 / r96410;
double r96412 = pow(r96411, r96403);
double r96413 = r96407 + r96412;
double r96414 = sqrt(r96413);
double r96415 = r96406 * r96414;
double r96416 = -inf.0;
bool r96417 = r96415 <= r96416;
double r96418 = 2.0600668909547137e+306;
bool r96419 = r96415 <= r96418;
double r96420 = !r96419;
bool r96421 = r96417 || r96420;
double r96422 = 0.25;
double r96423 = sqrt(r96422);
double r96424 = r96423 * r96408;
double r96425 = 0.5;
double r96426 = r96425 * r96402;
double r96427 = cos(r96426);
double r96428 = r96400 * r96427;
double r96429 = r96424 / r96428;
double r96430 = r96406 * r96429;
double r96431 = r96421 ? r96430 : r96415;
return r96431;
}



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 2.0600668909547137e+306 < (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))) Initial program 63.6
Taylor expanded around inf 45.8
if -inf.0 < (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))) < 2.0600668909547137e+306Initial program 0.1
Final simplification13.0
herbie shell --seed 2019323
(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)))))