\[x + \left(y - z\right) \cdot \frac{t - x}{a - z}\]
x + \left(y - z\right) \cdot \frac{t - x}{a - z}
double f(double x, double y, double z, double t, double a) {
        double r8222 = x;
        double r8223 = y;
        double r8224 = z;
        double r8225 = r8223 - r8224;
        double r8226 = t;
        double r8227 = r8226 - r8222;
        double r8228 = a;
        double r8229 = r8228 - r8224;
        double r8230 = r8227 / r8229;
        double r8231 = r8225 * r8230;
        double r8232 = r8222 + r8231;
        return r8232;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019179 +o rules:numerics
(FPCore (x y z t a)
  :name "Numeric.Signal:interpolate   from hsignal-0.2.7.1"
  (+ x (* (- y z) (/ (- t x) (- a z)))))

Backtrace

result arity mismatch; expected number of values not received expected: 2 received: 1 in: local-binding form values...: 0LC
loop/data/pavpan/nightlies/herbie/various-cleanup/src/core/extraction.rkt252
(unnamed)/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt260
simplify!/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt2170
run-improve43/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt3390
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.0/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.0/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128