Exception for exp-w (used to crash)

• could not determine a ground truth

  1. w = 2.00000000000000007e154
  2. l = -2

Specification

Math

\[\begin{array}{l} \\ e^{-w} \cdot {\ell}^{\left(e^{w}\right)} \end{array} \]

FPCore

(FPCore (w l) :precision binary64 (* (exp (- w)) (pow l (exp w))))

C

double code(double w, double l) {
	return exp(-w) * pow(l, exp(w));
}

Fortran

real(8) function code(w, l)
    real(8), intent (in) :: w
    real(8), intent (in) :: l
    code = exp(-w) * (l ** exp(w))
end function

Java

public static double code(double w, double l) {
	return Math.exp(-w) * Math.pow(l, Math.exp(w));
}

Python

def code(w, l):
	return math.exp(-w) * math.pow(l, math.exp(w))

Julia

function code(w, l)
	return Float64(exp(Float64(-w)) * (l ^ exp(w)))
end

MATLAB

function tmp = code(w, l)
	tmp = exp(-w) * (l ^ exp(w));
end

Wolfram

code[w_, l_] := N[(N[Exp[(-w)], $MachinePrecision] * N[Power[l, N[Exp[w], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

Reproduce

herbie shell --seed 2024039 
(FPCore (w l)
  :name "exp-w (used to crash)"
  :precision binary64
  (* (exp (- w)) (pow l (exp w))))

Please file a bug report with this information.

Backtrace

member: not a proper list in: 1		L	C
gather-multiplicative-terms	/home/nightlies/herbie/sound-rules/src/core/reduce.rkt	125	0
simplify-node*	/home/nightlies/herbie/sound-rules/src/core/reduce.rkt	84	0
hash-ref!	/usr/local/racket/collects/racket/private/more-scheme.rkt	377	2
hash-ref!	/usr/local/racket/collects/racket/private/more-scheme.rkt	377	2
approximate	/home/nightlies/herbie/sound-rules/src/core/taylor.rkt	7	0
taylor-expr	/home/nightlies/herbie/sound-rules/src/patch.rkt	89	0
taylor-alt	/home/nightlies/herbie/sound-rules/src/patch.rkt	96	0
gen-series!	/home/nightlies/herbie/sound-rules/src/patch.rkt	109	0
patch-table-run	/home/nightlies/herbie/sound-rules/src/patch.rkt	257	0
(unnamed)	/usr/local/racket/collects/racket/contract/private/arrow-val-first.rkt	486	18
run-iter!	/home/nightlies/herbie/sound-rules/src/mainloop.rkt	288	0
mutate!	/home/nightlies/herbie/sound-rules/src/mainloop.rkt	340	0
run-improve!	/home/nightlies/herbie/sound-rules/src/mainloop.rkt	326	0
get-alternatives/report	/home/nightlies/herbie/sound-rules/src/sandbox.rkt	169	0
(unnamed)	/home/nightlies/herbie/sound-rules/src/sandbox.rkt	262	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