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

\left(\left(x \cdot y + y \cdot y\right) - y \cdot z\right) - y \cdot y

double f(double x, double y, double z) {
        double r8928 = x;
        double r8929 = y;
        double r8930 = r8928 * r8929;
        double r8931 = r8929 * r8929;
        double r8932 = r8930 + r8931;
        double r8933 = z;
        double r8934 = r8929 * r8933;
        double r8935 = r8932 - r8934;
        double r8936 = r8935 - r8931;
        return r8936;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019191 
(FPCore (x y z)
  :name "Linear.Quaternion:$c/ from linear-1.19.1.3, C"

  :herbie-target
  (* (- x z) y)

  (- (- (+ (* x y) (* y y)) (* y z)) (* y y)))

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