\[x + \frac{y}{1.128379167095512558560699289955664426088 \cdot e^{z} - x \cdot y}\]
x + \frac{y}{1.128379167095512558560699289955664426088 \cdot e^{z} - x \cdot y}
double f(double x, double y, double z) {
        double r8810 = x;
        double r8811 = y;
        double r8812 = 1.1283791670955126;
        double r8813 = z;
        double r8814 = exp(r8813);
        double r8815 = r8812 * r8814;
        double r8816 = r8810 * r8811;
        double r8817 = r8815 - r8816;
        double r8818 = r8811 / r8817;
        double r8819 = r8810 + r8818;
        return r8819;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019305 
(FPCore (x y z)
  :name "Numeric.SpecFunctions:invErfc from math-functions-0.1.5.2, A"
  :precision binary64

  :herbie-target
  (+ x (/ 1 (- (* (/ 1.12837916709551256 y) (exp z)) x)))

  (+ x (/ y (- (* 1.12837916709551256 (exp z)) (* x y)))))

Backtrace

exact?: contract violation expected: number? given: 'h1LC
egg-parsed->expr/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/eggmath.rkt650
for-loop/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/eggmath.rkt706
egg-parsed->expr/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/eggmath.rkt650
(unnamed)/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/simplify.rkt498
egraph-add-exprs/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/eggmath.rkt1220
egraph-run/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/eggmath.rkt550
(unnamed)/data/pavpan/nightlies/herbie/eggmath-testversion/src/core/simplify.rkt380
simplify!/data/pavpan/nightlies/herbie/eggmath-testversion/src/mainloop.rkt2230
run-improve47/data/pavpan/nightlies/herbie/eggmath-testversion/src/mainloop.rkt3450
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.2/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.2/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128