Exception for ENA, Section 1.4, Exercise 4d

Specification

\[\left(0 \leq x \land x \leq 1000000000\right) \land \left(-1 \leq \varepsilon \land \varepsilon \leq 1\right)\]

Math

\[\begin{array}{l} \\ x - \sqrt{x \cdot x - \varepsilon} \end{array} \]

FPCore

(FPCore (x eps) :precision binary64 (- x (sqrt (- (* x x) eps))))

C

double code(double x, double eps) {
	return x - sqrt(((x * x) - eps));
}

Fortran

real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = x - sqrt(((x * x) - eps))
end function

Java

public static double code(double x, double eps) {
	return x - Math.sqrt(((x * x) - eps));
}

Python

def code(x, eps):
	return x - math.sqrt(((x * x) - eps))

Julia

function code(x, eps)
	return Float64(x - sqrt(Float64(Float64(x * x) - eps)))
end

MATLAB

function tmp = code(x, eps)
	tmp = x - sqrt(((x * x) - eps));
end

Wolfram

code[x_, eps_] := N[(x - N[Sqrt[N[(N[(x * x), $MachinePrecision] - eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]

Reproduce

herbie shell --seed 2024283 
(FPCore (x eps)
  :name "ENA, Section 1.4, Exercise 4d"
  :precision binary64
  :pre (and (and (<= 0.0 x) (<= x 1000000000.0)) (and (<= -1.0 eps) (<= eps 1.0)))

  :alt
  (! :herbie-platform default (/ eps (+ x (sqrt (- (* x x) eps)))))

  (- x (sqrt (- (* x x) eps))))

Please file a bug report with this information.

Backtrace

eprintf: format string requires 0 arguments, given 1; arguments were: '(#s(si 1 2) #s(si 2 4))		L	C
err-lsts->split-indices	/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt	219	0
option-on-expr	/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt	120	0
infer-splitpoints	/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt	56	0
loop	/home/nightlies/herbie/zane-regimes-old/src/core/regimes.rkt	41	2
make-regime!	/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt	350	0
extract!	/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt	79	0
run-improve!	/home/nightlies/herbie/zane-regimes-old/src/core/mainloop.rkt	45	0
get-alternatives/report	/home/nightlies/herbie/zane-regimes-old/src/api/sandbox.rkt	186	0
(unnamed)	/home/nightlies/herbie/zane-regimes-old/src/api/sandbox.rkt	282	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