\[\left(x \cdot \log y + z \cdot \log \left(1 - y\right)\right) - t\]

\left(x \cdot \log y + z \cdot \log \left(1 - y\right)\right) - t

double f(double x, double y, double z, double t) {
        double r8699 = x;
        double r8700 = y;
        double r8701 = log(r8700);
        double r8702 = r8699 * r8701;
        double r8703 = z;
        double r8704 = 1.0;
        double r8705 = r8704 - r8700;
        double r8706 = log(r8705);
        double r8707 = r8703 * r8706;
        double r8708 = r8702 + r8707;
        double r8709 = t;
        double r8710 = r8708 - r8709;
        return r8710;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019179 
(FPCore (x y z t)
  :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, B"

  :herbie-target
  (- (* (- z) (+ (+ (* 0.5 (* y y)) y) (* (/ 0.3333333333333333 (* 1.0 (* 1.0 1.0))) (* y (* y y))))) (- t (* x (log y))))

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

Backtrace

result arity mismatch; expected number of values not received expected: 2 received: 1 in: local-binding form values...: 0		L	C
loop	/data/pavpan/nightlies/herbie/various-cleanup/src/core/extraction.rkt	25	2
(unnamed)	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	26	0
simplify!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	217	0
run-improve43	/data/pavpan/nightlies/herbie/various-cleanup/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