Hyperbolic tangent

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \frac{e^{x} - t\_0}{e^{x} + t\_0} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (exp (- x)))) (/ (- (exp x) t_0) (+ (exp x) t_0))))
double code(double x) {
	double t_0 = exp(-x);
	return (exp(x) - t_0) / (exp(x) + t_0);
}

real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = exp(-x)
    code = (exp(x) - t_0) / (exp(x) + t_0)
end function

public static double code(double x) {
	double t_0 = Math.exp(-x);
	return (Math.exp(x) - t_0) / (Math.exp(x) + t_0);
}

def code(x):
	t_0 = math.exp(-x)
	return (math.exp(x) - t_0) / (math.exp(x) + t_0)

function code(x)
	t_0 = exp(Float64(-x))
	return Float64(Float64(exp(x) - t_0) / Float64(exp(x) + t_0))
end

function tmp = code(x)
	t_0 = exp(-x);
	tmp = (exp(x) - t_0) / (exp(x) + t_0);
end

code[x_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, N[(N[(N[Exp[x], $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[Exp[x], $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]]

\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-x}\\
\frac{e^{x} - t\_0}{e^{x} + t\_0}
\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024278 
(FPCore (x)
  :name "Hyperbolic tangent"
  :precision binary64
  (/ (- (exp x) (exp (- x))) (+ (exp x) (exp (- x)))))

Please file a bug report with this information.

Backtrace

Invalid inputLC
rival-apply/home/nightlies/.local/share/racket/8.10/pkgs/rival/eval/main.rkt650
(unnamed)/usr/share/racket/collects/racket/contract/private/arrow-val-first.rkt48618
f169.../match/compiler.rkt55940
compute-local-errors/home/nightlies/herbie/zane-concrete-values/src/core/localize.rkt1320
actual-errors/home/nightlies/herbie/zane-concrete-values/src/core/explain.rkt350
generate-timelines/home/nightlies/herbie/zane-concrete-values/src/core/explain.rkt4980
explain!/home/nightlies/herbie/zane-concrete-values/src/core/mainloop.rkt3230
run-improve!/home/nightlies/herbie/zane-concrete-values/src/core/mainloop.rkt450
get-alternatives/report/home/nightlies/herbie/zane-concrete-values/src/api/sandbox.rkt1860
(unnamed)/home/nightlies/herbie/zane-concrete-values/src/api/sandbox.rkt2826
(unnamed)/usr/share/racket/pkgs/profile-lib/main.rkt4010
profile-thunk/usr/share/racket/pkgs/profile-lib/main.rkt90
(unnamed)/usr/share/racket/collects/racket/engine.rkt4224