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

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

double f(double x, double y, double z) {
        double r9381 = x;
        double r9382 = y;
        double r9383 = r9381 * r9382;
        double r9384 = r9382 * r9382;
        double r9385 = r9383 - r9384;
        double r9386 = r9385 + r9384;
        double r9387 = z;
        double r9388 = r9382 * r9387;
        double r9389 = r9386 - r9388;
        return r9389;
}

Reproduce

Please include this information when filing a bug report:

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

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

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