\[x + \frac{e^{y \cdot \log \left(\frac{y}{z + y}\right)}}{y}\]
x + \frac{e^{y \cdot \log \left(\frac{y}{z + y}\right)}}{y}
double code(double x, double y, double z) {
	return ((double) (x + ((double) (((double) exp(((double) (y * ((double) log(((double) (y / ((double) (z + y)))))))))) / y))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020165 
(FPCore (x y z)
  :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, G"
  :precision binary64

  :herbie-target
  (if (< (/ y (+ z y)) 7.1154157597908e-315) (+ x (/ (exp (/ -1.0 z)) y)) (+ x (/ (exp (log (pow (/ y (+ y z)) y))) y)))

  (+ x (/ (exp (* y (log (/ y (+ z y))))) y)))

Backtrace

ival-hi: contract violation expected: ival? given: #<procedure:interval>LC
for-loop/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt3711
hyperrect-weight/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt360
total-weight/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1132
log-space-improvement/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1100
(unnamed)/opt/racket-7.5/collects/racket/contract/private/arrow-higher-order.rkt37533
get-hyperrects/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1230
make-sampler/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1470
prepare-points-intervals/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt900
run-improve47/data/pavpan/nightlies/herbie/ival-find-range/src/mainloop.rkt3650
.../more-scheme.rkt:261:28unknown
run/opt/racket-7.5/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.5/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.5/collects/racket/private/more-scheme.rkt26128

Reproduce

herbie shell --seed 2020165 
(FPCore (x y z)
  :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, G"
  :precision binary64

  :herbie-target
  (if (< (/ y (+ z y)) 7.1154157597908e-315) (+ x (/ (exp (/ -1.0 z)) y)) (+ x (/ (exp (log (pow (/ y (+ y z)) y))) y)))

  (+ x (/ (exp (* y (log (/ y (+ z y))))) y)))