\[\frac{2 + \left(\left(\sqrt{2} \cdot \left(\sin x - \frac{\sin y}{16}\right)\right) \cdot \left(\sin y - \frac{\sin x}{16}\right)\right) \cdot \left(\cos x - \cos y\right)}{3 \cdot \left(\left(1 + \frac{\sqrt{5} - 1}{2} \cdot \cos x\right) + \frac{3 - \sqrt{5}}{2} \cdot \cos y\right)}\]

\frac{2 + \left(\left(\sqrt{2} \cdot \left(\sin x - \frac{\sin y}{16}\right)\right) \cdot \left(\sin y - \frac{\sin x}{16}\right)\right) \cdot \left(\cos x - \cos y\right)}{3 \cdot \left(\left(1 + \frac{\sqrt{5} - 1}{2} \cdot \cos x\right) + \frac{3 - \sqrt{5}}{2} \cdot \cos y\right)}

double f(double x, double y) {
        double r148549 = 2.0;
        double r148550 = sqrt(r148549);
        double r148551 = x;
        double r148552 = sin(r148551);
        double r148553 = y;
        double r148554 = sin(r148553);
        double r148555 = 16.0;
        double r148556 = r148554 / r148555;
        double r148557 = r148552 - r148556;
        double r148558 = r148550 * r148557;
        double r148559 = r148552 / r148555;
        double r148560 = r148554 - r148559;
        double r148561 = r148558 * r148560;
        double r148562 = cos(r148551);
        double r148563 = cos(r148553);
        double r148564 = r148562 - r148563;
        double r148565 = r148561 * r148564;
        double r148566 = r148549 + r148565;
        double r148567 = 3.0;
        double r148568 = 1.0;
        double r148569 = 5.0;
        double r148570 = sqrt(r148569);
        double r148571 = r148570 - r148568;
        double r148572 = r148571 / r148549;
        double r148573 = r148572 * r148562;
        double r148574 = r148568 + r148573;
        double r148575 = r148567 - r148570;
        double r148576 = r148575 / r148549;
        double r148577 = r148576 * r148563;
        double r148578 = r148574 + r148577;
        double r148579 = r148567 * r148578;
        double r148580 = r148566 / r148579;
        return r148580;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 +o rules:numerics
(FPCore (x y)
  :name "Diagrams.TwoD.Path.Metafont.Internal:hobbyF from diagrams-contrib-1.3.0.5"
  :precision binary64
  (/ (+ 2 (* (* (* (sqrt 2) (- (sin x) (/ (sin y) 16))) (- (sin y) (/ (sin x) 16))) (- (cos x) (cos y)))) (* 3 (+ (+ 1 (* (/ (- (sqrt 5) 1) 2) (cos x))) (* (/ (- 3 (sqrt 5)) 2) (cos y))))))

Backtrace

get-representation: Unknown representation real		L	C
(unnamed)	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt	65	3
filter	/opt/racket-7.2/collects/racket/private/list.rkt	256	2
infer-splitpoints	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt	34	0
get-final-combination	/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt	369	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.2/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.2/collects/racket/private/more-scheme.rkt	261	28