Exception for x / (x^2 + 1)

Math

\[\frac{x}{x \cdot x + 1} \]

FPCore

(FPCore (x) :precision binary64 (/ x (+ (* x x) 1.0)))

C

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

Fortran

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

Java

public static double code(double x) {
	return x / ((x * x) + 1.0);
}

Python

def code(x):
	return x / ((x * x) + 1.0)

Julia

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

MATLAB

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

Wolfram

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

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2023098 
(FPCore (x)
  :name "x / (x^2 + 1)"
  :precision binary64

  :herbie-target
  (/ 1.0 (+ x (/ 1.0 x)))

  (/ x (+ (* x x) 1.0)))

Backtrace

hash-ref: no value found for key key: 'false		L	C
(unnamed)	/home/nightlies/herbie/using-ruler-nightlies/src/syntax/syntax.rkt	230	2
f336	.../match/compiler.rkt	548	40
expand-parametric	/home/nightlies/herbie/using-ruler-nightlies/src/syntax/sugar.rkt	62	0
(unnamed)	/home/nightlies/herbie/using-ruler-nightlies/src/core/egg-herbie.rkt	255	9
rule->egg-rules	/home/nightlies/herbie/using-ruler-nightlies/src/core/egg-herbie.rkt	224	0
expand-rules	/home/nightlies/herbie/using-ruler-nightlies/src/core/egg-herbie.rkt	488	0
egraph-run-rules	/home/nightlies/herbie/using-ruler-nightlies/src/core/egg-herbie.rkt	509	0
(unnamed)	/home/nightlies/herbie/using-ruler-nightlies/src/core/simplify.rkt	58	3
with-egraph	/home/nightlies/herbie/using-ruler-nightlies/src/core/egg-herbie.rkt	333	0
simplify-batch	/home/nightlies/herbie/using-ruler-nightlies/src/core/simplify.rkt	23	0
(unnamed)	/usr/share/racket/collects/racket/contract/private/arrow-higher-order.rkt	379	33
get-swaps	/home/nightlies/herbie/using-ruler-nightlies/src/symmetry.rkt	6	0
connected-components	/home/nightlies/herbie/using-ruler-nightlies/src/symmetry.rkt	18	0
run-improve!	/home/nightlies/herbie/using-ruler-nightlies/src/mainloop.rkt	320	0
run-herbie	/home/nightlies/herbie/using-ruler-nightlies/src/sandbox.rkt	57	0
(unnamed)	/home/nightlies/herbie/using-ruler-nightlies/src/sandbox.rkt	133	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