\[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}\]

x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}

double code(double x, double y, double z, double t) {
	return ((double) (x - ((double) (((double) log(((double) (((double) (1.0 - y)) + ((double) (y * ((double) exp(z)))))))) / t))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020128 
(FPCore (x y z t)
  :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
  :precision binary64

  :herbie-target
  (if (< z -2.8874623088207947e+119) (- (- x (/ (/ (- 0.5) (* y t)) (* z z))) (* (/ (- 0.5) (* y t)) (/ (/ 2.0 z) (* z z)))) (- x (/ (log (+ 1.0 (* z y))) t)))

  (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))

Backtrace

random-bits: contract violation expected: Positive-Integer given: 0		L	C
random-ranges	/data/pavpan/nightlies/herbie/separate-biginterval/src/common.rkt	139	0
sample-multi-bounded	/data/pavpan/nightlies/herbie/separate-biginterval/src/points.rkt	14	0
(unnamed)	/data/pavpan/nightlies/herbie/separate-biginterval/src/points.rkt	127	6
prepare-points-intervals	/data/pavpan/nightlies/herbie/separate-biginterval/src/points.rkt	134	0
pred	/data/pavpan/nightlies/herbie/separate-biginterval/src/core/regimes.rkt	200	4
for-loop	/data/pavpan/nightlies/herbie/separate-biginterval/src/core/regimes.rkt	230	9
sindices->spoints	/data/pavpan/nightlies/herbie/separate-biginterval/src/core/regimes.rkt	190	0
f37	unknown
get-final-combination	/data/pavpan/nightlies/herbie/separate-biginterval/src/mainloop.rkt	390	0
.../more-scheme.rkt:261:28	unknown
run	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.5/collects/racket/private/more-scheme.rkt	261	28

Reproduce

herbie shell --seed 2020128 
(FPCore (x y z t)
  :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
  :precision binary64

  :herbie-target
  (if (< z -2.8874623088207947e+119) (- (- x (/ (/ (- 0.5) (* y t)) (* z z))) (* (/ (- 0.5) (* y t)) (/ (/ 2.0 z) (* z z)))) (- x (/ (log (+ 1.0 (* z y))) t)))

  (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))