\[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\]

\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}}

double f(double J, double K, double U) {
        double r8046500 = -2.0;
        double r8046501 = J;
        double r8046502 = r8046500 * r8046501;
        double r8046503 = K;
        double r8046504 = 2.0;
        double r8046505 = r8046503 / r8046504;
        double r8046506 = cos(r8046505);
        double r8046507 = r8046502 * r8046506;
        double r8046508 = 1.0;
        double r8046509 = U;
        double r8046510 = r8046504 * r8046501;
        double r8046511 = r8046510 * r8046506;
        double r8046512 = r8046509 / r8046511;
        double r8046513 = pow(r8046512, r8046504);
        double r8046514 = r8046508 + r8046513;
        double r8046515 = sqrt(r8046514);
        double r8046516 = r8046507 * r8046515;
        return r8046516;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019173 
(FPCore (J K U)
  :name "Maksimov and Kolovsky, Equation (3)"
  (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))))

Backtrace

hash-ref: no value found for key key: #<enode 286(286)>		L	C
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	197	2
extractor-extract	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	196	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	35	2
(unnamed)	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	26	0
simplify!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	217	0
run-iter!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	320	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	354	4
run-improve43	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	339	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28