\[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\]

\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}

double f(double x, double y, double z) {
        double r526630 = 4.0;
        double r526631 = x;
        double r526632 = y;
        double r526633 = r526631 - r526632;
        double r526634 = z;
        double r526635 = 0.5;
        double r526636 = r526634 * r526635;
        double r526637 = r526633 - r526636;
        double r526638 = r526630 * r526637;
        double r526639 = r526638 / r526634;
        return r526639;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 
(FPCore (x y z)
  :name "Data.Array.Repa.Algorithms.ColorRamp:rampColorHotToCold from repa-algorithms-3.4.0.1, B"
  :precision binary64

  :herbie-target
  (- (* 4 (/ x z)) (+ 2 (* 4 (/ y z))))

  (/ (* 4 (- (- x y) (* z 0.5))) z))

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