\[x \cdot 0.5 + y \cdot \left(\left(1 - z\right) + \log z\right)\]

x \cdot 0.5 + y \cdot \left(\left(1 - z\right) + \log z\right)

double f(double x, double y, double z) {
        double r8707 = x;
        double r8708 = 0.5;
        double r8709 = r8707 * r8708;
        double r8710 = y;
        double r8711 = 1.0;
        double r8712 = z;
        double r8713 = r8711 - r8712;
        double r8714 = log(r8712);
        double r8715 = r8713 + r8714;
        double r8716 = r8710 * r8715;
        double r8717 = r8709 + r8716;
        return r8717;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019191 
(FPCore (x y z)
  :name "System.Random.MWC.Distributions:gamma from mwc-random-0.13.3.2"

  :herbie-target
  (- (+ y (* 0.5 x)) (* y (- z (log z))))

  (+ (* x 0.5) (* y (+ (- 1.0 z) (log z)))))

Backtrace

get-representation: Unknown representation #f		L	C
loop	/data/pavpan/nightlies/herbie/interface2/src/points.rkt	122	4
prepare-points	/data/pavpan/nightlies/herbie/interface2/src/points.rkt	146	0
setup-prog!34	/data/pavpan/nightlies/herbie/interface2/src/mainloop.rkt	67	0
run-improve43	/data/pavpan/nightlies/herbie/interface2/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