\[-1 \lt x \land x \lt 1\]
\[\frac{\log \left(1 - x\right)}{\log \left(1 + x\right)}\]
\frac{\log \left(1 - x\right)}{\log \left(1 + x\right)}
double code(double x) {
	return ((double) (((double) log(((double) (1.0 - x)))) / ((double) log(((double) (1.0 + x))))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020155 
(FPCore (x)
  :name "qlog (example 3.10)"
  :precision binary64
  :pre (and (< -1.0 x) (< x 1.0))

  :herbie-target
  (neg (+ (+ (+ 1.0 x) (/ (* x x) 2.0)) (* 0.4166666666666667 (pow x 3.0))))

  (/ (log (- 1.0 x)) (log (+ 1.0 x))))

Backtrace

not inclusive intervalsLC
fpbench-ival->ival/data/pavpan/nightlies/herbie/ival-find-range/src/findroot.rkt630
loopunknown
range-table->hyperrects/data/pavpan/nightlies/herbie/ival-find-range/src/findroot.rkt580
make-sampler/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt1240
prepare-points-intervals/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt1550
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 2020155 
(FPCore (x)
  :name "qlog (example 3.10)"
  :precision binary64
  :pre (and (< -1.0 x) (< x 1.0))

  :herbie-target
  (neg (+ (+ (+ 1.0 x) (/ (* x x) 2.0)) (* 0.4166666666666667 (pow x 3.0))))

  (/ (log (- 1.0 x)) (log (+ 1.0 x))))