Development.Shake.Progress:message from shake-0.15.5

Average Error: 0.4 → 0.2

Time: 12.6s

Precision: binary64

Cost: 448

Math

\[\frac{x \cdot 100}{x + y} \]

↓

\[\frac{\frac{x}{x + y}}{0.01} \]

FPCore

(FPCore (x y) :precision binary64 (/ (* x 100.0) (+ x y)))

↓

(FPCore (x y) :precision binary64 (/ (/ x (+ x y)) 0.01))

C

double code(double x, double y) {
	return (x * 100.0) / (x + y);
}

↓

double code(double x, double y) {
	return (x / (x + y)) / 0.01;
}

Fortran

real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x * 100.0d0) / (x + y)
end function

↓

real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x / (x + y)) / 0.01d0
end function

Java

public static double code(double x, double y) {
	return (x * 100.0) / (x + y);
}

↓

public static double code(double x, double y) {
	return (x / (x + y)) / 0.01;
}

Python

def code(x, y):
	return (x * 100.0) / (x + y)

↓

def code(x, y):
	return (x / (x + y)) / 0.01

Julia

function code(x, y)
	return Float64(Float64(x * 100.0) / Float64(x + y))
end

↓

function code(x, y)
	return Float64(Float64(x / Float64(x + y)) / 0.01)
end

MATLAB

function tmp = code(x, y)
	tmp = (x * 100.0) / (x + y);
end

↓

function tmp = code(x, y)
	tmp = (x / (x + y)) / 0.01;
end

Wolfram

code[x_, y_] := N[(N[(x * 100.0), $MachinePrecision] / N[(x + y), $MachinePrecision]), $MachinePrecision]

↓

code[x_, y_] := N[(N[(x / N[(x + y), $MachinePrecision]), $MachinePrecision] / 0.01), $MachinePrecision]

Target

Original	0.4
Target	0.2
Herbie	0.2

\[\frac{x}{1} \cdot \frac{100}{x + y} \]

Derivation

1. Initial program 0.4

   \[\frac{x \cdot 100}{x + y} \]

2. Applied egg-rr 0.2

   \[\leadsto \color{blue}{\frac{\frac{x}{x + y}}{0.01}} \]

Alternatives

Alternative 1
Error	16.8
Cost	584

\[\begin{array}{l} t_0 := 100 \cdot \frac{x}{y}\\ \mathbf{if}\;y \leq -5.5 \cdot 10^{-87}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 1.12 \cdot 10^{-66}:\\ \;\;\;\;100\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \]

Alternative 2
Error	16.8
Cost	584

\[\begin{array}{l} \mathbf{if}\;y \leq -5.5 \cdot 10^{-87}:\\ \;\;\;\;\frac{\frac{x}{y}}{0.01}\\ \mathbf{elif}\;y \leq 3 \cdot 10^{-63}:\\ \;\;\;\;100\\ \mathbf{else}:\\ \;\;\;\;100 \cdot \frac{x}{y}\\ \end{array} \]

Alternative 3
Error	0.2
Cost	448

\[\frac{100}{x + y} \cdot x \]

Alternative 4
Error	31.7
Cost	64

\[100 \]

Reproduce

herbie shell --seed 2023010 
(FPCore (x y)
  :name "Development.Shake.Progress:message from shake-0.15.5"
  :precision binary64

  :herbie-target
  (* (/ x 1.0) (/ 100.0 (+ x y)))

  (/ (* x 100.0) (+ x y)))