Exception for Quotient of sum of exps

Math

\[\frac{e^{a}}{e^{a} + e^{b}} \]

FPCore

(FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))

C

double code(double a, double b) {
	return exp(a) / (exp(a) + exp(b));
}

Fortran

real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = exp(a) / (exp(a) + exp(b))
end function

Java

public static double code(double a, double b) {
	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
}

Python

def code(a, b):
	return math.exp(a) / (math.exp(a) + math.exp(b))

Julia

function code(a, b)
	return Float64(exp(a) / Float64(exp(a) + exp(b)))
end

MATLAB

function tmp = code(a, b)
	tmp = exp(a) / (exp(a) + exp(b));
end

Wolfram

code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2022150 
(FPCore (a b)
  :name "Quotient of sum of exps"
  :precision binary64

  :herbie-target
  (/ 1.0 (+ 1.0 (exp (- b a))))

  (/ (exp a) (+ (exp a) (exp b))))

Backtrace

application: required keyword argument not supplied procedure: batch-egg-rewrite required keyword: #:rules arguments...: '(#<rule erfc-erf_binary64> #<rule erf-erfc_binary64> #<rule erf-odd_binary64> #<rule prod-diff_binary64> #<rule hypot-udef_binary64> #<rule expm1-log1p-u_binary64> #<rule log1p-expm1-u_binary64> #<rule log1p-udef_binary64> #<rule expm1-udef_binary64> #... #:depths '(1) #:roots '((2))		L	C
(unnamed)	/opt/racket-8.1/collects/racket/private/kw.rkt	1558	14
rewrite-expressions	/data/pavpan/nightlies/herbie/timeline/src/core/matcher.rkt	171	0
gen-rewrites!	/data/pavpan/nightlies/herbie/timeline/src/patch.rkt	144	0
patch-table-run	/data/pavpan/nightlies/herbie/timeline/src/patch.rkt	291	0
(unnamed)	/opt/racket-8.1/collects/racket/contract/private/arrow-val-first.rkt	486	18
run-iter!	/data/pavpan/nightlies/herbie/timeline/src/mainloop.rkt	246	0
mutate!	/data/pavpan/nightlies/herbie/timeline/src/mainloop.rkt	379	0
run-improve!	/data/pavpan/nightlies/herbie/timeline/src/mainloop.rkt	326	0
(unnamed)	/data/pavpan/nightlies/herbie/timeline/src/sandbox.rkt	66	6
(unnamed)	/opt/racket-8.1/share/pkgs/profile-lib/main.rkt	40	10
profile-thunk	/opt/racket-8.1/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-8.1/collects/racket/engine.rkt	42	24