?

\[x \geq 1\]

\[\log \left(x + \sqrt{x \cdot x - 1}\right) \]

(FPCore (x) :precision binary32 (log (+ x (sqrt (- (* x x) 1.0)))))

float code(float x) {
	return logf((x + sqrtf(((x * x) - 1.0f))));
}

real(4) function code(x)
    real(4), intent (in) :: x
    code = log((x + sqrt(((x * x) - 1.0e0))))
end function

function code(x)
	return log(Float32(x + sqrt(Float32(Float32(x * x) - Float32(1.0)))))
end

function tmp = code(x)
	tmp = log((x + sqrt(((x * x) - single(1.0)))));
end

\log \left(x + \sqrt{x \cdot x - 1}\right)

Reproduce?

Please include this information when filing a bug report:

herbie shell --seed 2023245 
(FPCore (x)
  :name "Rust f32::acosh"
  :precision binary32
  :pre (>= x 1.0)

  :herbie-target
  (log (+ x (* (sqrt (- x 1.0)) (sqrt (+ x 1.0)))))

  (log (+ x (sqrt (- (* x x) 1.0)))))

Backtrace

arb->=: arity mismatch; the expected number of arguments does not match the given number expected: 0 given: 2		L	C
f	/home/nightlies/herbie/arb-support/src/programs.rkt	187	2
(unnamed)	/home/nightlies/herbie/arb-support/src/ground-truth.rkt	23	2
search-step	/home/nightlies/herbie/arb-support/src/searchreals.rkt	37	0
find-intervals	/home/nightlies/herbie/arb-support/src/searchreals.rkt	87	0
make-sampler	/home/nightlies/herbie/arb-support/src/sampling.rkt	94	0
sample-points	/home/nightlies/herbie/arb-support/src/ground-truth.rkt	64	0
setup-context!	/home/nightlies/herbie/arb-support/src/mainloop.rkt	293	0
get-alternatives/report	/home/nightlies/herbie/arb-support/src/sandbox.rkt	148	0
(unnamed)	/home/nightlies/herbie/arb-support/src/sandbox.rkt	247	6
(unnamed)	/usr/share/racket/pkgs/profile-lib/main.rkt	40	10
profile-thunk	/usr/share/racket/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/usr/share/racket/collects/racket/engine.rkt	42	24