Expanding a square

Average Error: 39.5 → 0.0

Time: 2.0s

Precision: binary64

Cost: 320

Math

\[\left(x + 1\right) \cdot \left(x + 1\right) - 1 \]

↓

\[x \cdot \left(x + 2\right) \]

FPCore

(FPCore (x) :precision binary64 (- (* (+ x 1.0) (+ x 1.0)) 1.0))

↓

(FPCore (x) :precision binary64 (* x (+ x 2.0)))

C

double code(double x) {
	return ((x + 1.0) * (x + 1.0)) - 1.0;
}

↓

double code(double x) {
	return x * (x + 2.0);
}

Fortran

real(8) function code(x)
    real(8), intent (in) :: x
    code = ((x + 1.0d0) * (x + 1.0d0)) - 1.0d0
end function

↓

real(8) function code(x)
    real(8), intent (in) :: x
    code = x * (x + 2.0d0)
end function

Java

public static double code(double x) {
	return ((x + 1.0) * (x + 1.0)) - 1.0;
}

↓

public static double code(double x) {
	return x * (x + 2.0);
}

Python

def code(x):
	return ((x + 1.0) * (x + 1.0)) - 1.0

↓

def code(x):
	return x * (x + 2.0)

Julia

function code(x)
	return Float64(Float64(Float64(x + 1.0) * Float64(x + 1.0)) - 1.0)
end

↓

function code(x)
	return Float64(x * Float64(x + 2.0))
end

MATLAB

function tmp = code(x)
	tmp = ((x + 1.0) * (x + 1.0)) - 1.0;
end

↓

function tmp = code(x)
	tmp = x * (x + 2.0);
end

Wolfram

code[x_] := N[(N[(N[(x + 1.0), $MachinePrecision] * N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision]

↓

code[x_] := N[(x * N[(x + 2.0), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 39.5

   \[\left(x + 1\right) \cdot \left(x + 1\right) - 1 \]

2. Simplified 0.0

   \[\leadsto \color{blue}{x \cdot \left(x + 2\right)} \]
   Proof

   [Start] 39.5	\[ \left(x + 1\right) \cdot \left(x + 1\right) - 1 \]
   rational_best_45_simplify-56 [=>] 39.5	\[ \color{blue}{\left(x + 1\right) \cdot \left(x + 1\right) + -1} \]
   rational_best_45_simplify-73 [=>] 39.5	\[ \color{blue}{-1 + \left(x + 1\right) \cdot \left(x + 1\right)} \]
   rational_best_45_simplify-71 [<=] 39.5	\[ -1 + \color{blue}{\left(x \cdot \left(x + 1\right) + \left(x + 1\right) \cdot 1\right)} \]
   rational_best_45_simplify-8 [=>] 39.5	\[ -1 + \left(x \cdot \left(x + 1\right) + \color{blue}{\left(x + 1\right)}\right) \]
   rational_best_45_simplify-80 [=>] 34.0	\[ \color{blue}{x \cdot \left(x + 1\right) + \left(-1 + \left(x + 1\right)\right)} \]
   rational_best_45_simplify-80 [=>] 0.0	\[ x \cdot \left(x + 1\right) + \color{blue}{\left(x + \left(-1 + 1\right)\right)} \]
   metadata-eval [=>] 0.0	\[ x \cdot \left(x + 1\right) + \left(x + \color{blue}{0}\right) \]
   rational_best_45_simplify-3 [=>] 0.0	\[ x \cdot \left(x + 1\right) + \color{blue}{x} \]
   rational_best_45_simplify-91 [=>] 0.0	\[ \color{blue}{\left(x + 1\right) \cdot x} + x \]
   rational_best_45_simplify-8 [<=] 0.0	\[ \left(x + 1\right) \cdot x + \color{blue}{x \cdot 1} \]
   rational_best_45_simplify-71 [=>] 0.0	\[ \color{blue}{x \cdot \left(\left(x + 1\right) + 1\right)} \]
   rational_best_45_simplify-73 [=>] 0.0	\[ x \cdot \color{blue}{\left(1 + \left(x + 1\right)\right)} \]
   rational_best_45_simplify-80 [=>] 0.0	\[ x \cdot \color{blue}{\left(x + \left(1 + 1\right)\right)} \]
   metadata-eval [=>] 0.0	\[ x \cdot \left(x + \color{blue}{2}\right) \]

3. Final simplification 0.0

   \[\leadsto x \cdot \left(x + 2\right) \]

Alternatives

Alternative 1
Error	21.0
Cost	192

\[x + x \]

Reproduce

herbie shell --seed 2023098 
(FPCore (x)
  :name "Expanding a square"
  :precision binary64
  (- (* (+ x 1.0) (+ x 1.0)) 1.0))