Exception for Logistic function

\[0 \leq s \land s \leq 1.0651631\]

Math

\[\frac{1}{1 + e^{\frac{-x}{s}}} \]

FPCore

(FPCore (x s) :precision binary64 (/ 1.0 (+ 1.0 (exp (/ (- x) s)))))

C

double code(double x, double s) {
	return 1.0 / (1.0 + exp((-x / s)));
}

Fortran

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

Java

public static double code(double x, double s) {
	return 1.0 / (1.0 + Math.exp((-x / s)));
}

Python

def code(x, s):
	return 1.0 / (1.0 + math.exp((-x / s)))

Julia

function code(x, s)
	return Float64(1.0 / Float64(1.0 + exp(Float64(Float64(-x) / s))))
end

MATLAB

function tmp = code(x, s)
	tmp = 1.0 / (1.0 + exp((-x / s)));
end

Wolfram

code[x_, s_] := N[(1.0 / N[(1.0 + N[Exp[N[((-x) / s), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2022349 
(FPCore (x s)
  :name "Logistic function"
  :precision binary64
  :pre (and (<= 0.0 s) (<= s 1.0651631))
  (/ 1.0 (+ 1.0 (exp (/ (- x) s)))))

Backtrace

error writing to stream port system error: Broken pipe; errno=32		L	C
writeln	/usr/share/racket/collects/racket/private/misc.rkt	156	4
run-egglog	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/egglog/run-egglog.rkt	1301	0
run-simplify-input	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/core/simplify.rkt	74	0
simplify-batch	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/core/simplify.rkt	51	0
(unnamed)	/usr/share/racket/collects/racket/contract/private/arrow-higher-order.rkt	379	33
get-swaps	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/symmetry.rkt	6	0
connected-components	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/symmetry.rkt	20	0
run-improve!	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/mainloop.rkt	320	0
(unnamed)	/home/nightlies/nightlies/herbie/oflatt-egglog-ctx/src/sandbox.rkt	55	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