Average Error: 0.2 → 0.0
Time: 19.5s
Precision: binary64
Cost: 7232
\[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
\[\frac{x + -1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6 \]
(FPCore (x)
 :precision binary64
 (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))
(FPCore (x)
 :precision binary64
 (* (/ (+ x -1.0) (+ (+ x 1.0) (* 4.0 (sqrt x)))) 6.0))
double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
}
double code(double x) {
	return ((x + -1.0) / ((x + 1.0) + (4.0 * sqrt(x)))) * 6.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (6.0d0 * (x - 1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))
end function
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((x + (-1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))) * 6.0d0
end function
public static double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * Math.sqrt(x)));
}
public static double code(double x) {
	return ((x + -1.0) / ((x + 1.0) + (4.0 * Math.sqrt(x)))) * 6.0;
}
def code(x):
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * math.sqrt(x)))
def code(x):
	return ((x + -1.0) / ((x + 1.0) + (4.0 * math.sqrt(x)))) * 6.0
function code(x)
	return Float64(Float64(6.0 * Float64(x - 1.0)) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x))))
end
function code(x)
	return Float64(Float64(Float64(x + -1.0) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x)))) * 6.0)
end
function tmp = code(x)
	tmp = (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
end
function tmp = code(x)
	tmp = ((x + -1.0) / ((x + 1.0) + (4.0 * sqrt(x)))) * 6.0;
end
code[x_] := N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
code[x_] := N[(N[(N[(x + -1.0), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 6.0), $MachinePrecision]
\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}
\frac{x + -1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6

Error

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original0.2
Target0.1
Herbie0.0
\[\frac{6}{\frac{\left(x + 1\right) + 4 \cdot \sqrt{x}}{x - 1}} \]

Derivation

  1. Initial program 0.2

    \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
  2. Applied egg-rr0.0

    \[\leadsto \color{blue}{\frac{x + -1}{\mathsf{fma}\left(4, \sqrt{x}, x + 1\right)} \cdot 6} \]
  3. Applied egg-rr0.0

    \[\leadsto \frac{x + -1}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]

Alternatives

Alternative 1
Error1.5
Cost7236
\[\begin{array}{l} t_0 := \left(x + 1\right) + 4 \cdot \sqrt{x}\\ \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{-6}{t_0}\\ \mathbf{else}:\\ \;\;\;\;\frac{6 \cdot x}{t_0}\\ \end{array} \]
Alternative 2
Error2.1
Cost7108
\[\begin{array}{l} \mathbf{if}\;x \leq 0.85:\\ \;\;\;\;\frac{-6}{\left(x + 1\right) + 4 \cdot \sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x + -1}{x} \cdot 6\\ \end{array} \]
Alternative 3
Error2.9
Cost580
\[\begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{1 - x}{-0.16666666666666666}\\ \mathbf{else}:\\ \;\;\;\;\frac{x + -1}{x} \cdot 6\\ \end{array} \]
Alternative 4
Error2.9
Cost580
\[\begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{6 \cdot \left(x - 1\right)}{1}\\ \mathbf{else}:\\ \;\;\;\;\frac{x + -1}{x} \cdot 6\\ \end{array} \]
Alternative 5
Error2.9
Cost452
\[\begin{array}{l} \mathbf{if}\;x \leq 0.5:\\ \;\;\;\;-6\\ \mathbf{else}:\\ \;\;\;\;6 - \frac{6}{x}\\ \end{array} \]
Alternative 6
Error2.9
Cost452
\[\begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{1 - x}{-0.16666666666666666}\\ \mathbf{else}:\\ \;\;\;\;6 - \frac{6}{x}\\ \end{array} \]
Alternative 7
Error2.9
Cost196
\[\begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;-6\\ \mathbf{else}:\\ \;\;\;\;6\\ \end{array} \]
Alternative 8
Error33.1
Cost64
\[-6 \]

Error

Reproduce

herbie shell --seed 2023010 
(FPCore (x)
  :name "Data.Approximate.Numerics:blog from approximate-0.2.2.1"
  :precision binary64

  :herbie-target
  (/ 6.0 (/ (+ (+ x 1.0) (* 4.0 (sqrt x))) (- x 1.0)))

  (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))