Exception for Hyperbolic arc-(co)tangent

Specification

\[\begin{array}{l} \\ \frac{1}{2} \cdot \log \left(\frac{1 + x}{1 - x}\right) \end{array} \]

(FPCore (x) :precision binary64 (* (/ 1.0 2.0) (log (/ (+ 1.0 x) (- 1.0 x)))))

double code(double x) {
	return (1.0 / 2.0) * log(((1.0 + x) / (1.0 - x)));
}

real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / 2.0d0) * log(((1.0d0 + x) / (1.0d0 - x)))
end function

public static double code(double x) {
	return (1.0 / 2.0) * Math.log(((1.0 + x) / (1.0 - x)));
}

def code(x):
	return (1.0 / 2.0) * math.log(((1.0 + x) / (1.0 - x)))

function code(x)
	return Float64(Float64(1.0 / 2.0) * log(Float64(Float64(1.0 + x) / Float64(1.0 - x))))
end

function tmp = code(x)
	tmp = (1.0 / 2.0) * log(((1.0 + x) / (1.0 - x)));
end

code[x_] := N[(N[(1.0 / 2.0), $MachinePrecision] * N[Log[N[(N[(1.0 + x), $MachinePrecision] / N[(1.0 - x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

\begin{array}{l}

\\
\frac{1}{2} \cdot \log \left(\frac{1 + x}{1 - x}\right)
\end{array}

Reproduce

herbie shell --seed 2024196 
(FPCore (x)
  :name "Hyperbolic arc-(co)tangent"
  :precision binary64
  (* (/ 1.0 2.0) (log (/ (+ 1.0 x) (- 1.0 x)))))

Please file a bug report with this information.

Backtrace

vector-set!: contract violation expected: exact-nonnegative-integer? given: -1 argument position: 2nd first argument...: '#(#f #t #f #f #f #f #f #f #f #f)		L	C
backward-pass	/home/nightlies/rival/main/eval/adjust.rkt	8	0
rival-machine-adjust	/home/nightlies/rival/main/eval/run.rkt	98	0
rival-machine-full	/home/nightlies/rival/main/eval/main.rkt	16	0
rival-apply	/home/nightlies/rival/main/eval/main.rkt	56	0
(unnamed)	/usr/local/racket/collects/racket/contract/private/arrow-val-first.rkt	486	18
(unnamed)	/home/nightlies/herbie/main/src/sampling.rkt	159	4
ival-eval	/home/nightlies/herbie/main/src/sampling.rkt	153	0
<eval-prog-real>	/home/nightlies/herbie/main/src/sampling.rkt	188	2
predict-errors	/home/nightlies/herbie/main/src/explain.rkt	86	0
explain	/home/nightlies/herbie/main/src/explain.rkt	736	0
explain!	/home/nightlies/herbie/main/src/mainloop.rkt	339	0
mutate!	/home/nightlies/herbie/main/src/mainloop.rkt	62	0
run-improve!	/home/nightlies/herbie/main/src/mainloop.rkt	48	0
get-alternatives/report	/home/nightlies/herbie/main/src/sandbox.rkt	167	0
(unnamed)	/home/nightlies/herbie/main/src/sandbox.rkt	261	6
(unnamed)	/usr/local/racket/share/pkgs/profile-lib/main.rkt	40	10
profile-thunk	/usr/local/racket/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/usr/local/racket/collects/racket/engine.rkt	42	24