Radioactive exchange between two surfaces

Percentage Accurate: 85.6% → 99.8%
Time: 4.1s
Alternatives: 5
Speedup: 13.7×

Specification

?
\[\begin{array}{l} \\ {x}^{4} - {y}^{4} \end{array} \]
(FPCore (x y) :precision binary64 (- (pow x 4.0) (pow y 4.0)))
double code(double x, double y) {
	return pow(x, 4.0) - pow(y, 4.0);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x ** 4.0d0) - (y ** 4.0d0)
end function
public static double code(double x, double y) {
	return Math.pow(x, 4.0) - Math.pow(y, 4.0);
}
def code(x, y):
	return math.pow(x, 4.0) - math.pow(y, 4.0)
function code(x, y)
	return Float64((x ^ 4.0) - (y ^ 4.0))
end
function tmp = code(x, y)
	tmp = (x ^ 4.0) - (y ^ 4.0);
end
code[x_, y_] := N[(N[Power[x, 4.0], $MachinePrecision] - N[Power[y, 4.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{x}^{4} - {y}^{4}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 5 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 85.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ {x}^{4} - {y}^{4} \end{array} \]
(FPCore (x y) :precision binary64 (- (pow x 4.0) (pow y 4.0)))
double code(double x, double y) {
	return pow(x, 4.0) - pow(y, 4.0);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x ** 4.0d0) - (y ** 4.0d0)
end function
public static double code(double x, double y) {
	return Math.pow(x, 4.0) - Math.pow(y, 4.0);
}
def code(x, y):
	return math.pow(x, 4.0) - math.pow(y, 4.0)
function code(x, y)
	return Float64((x ^ 4.0) - (y ^ 4.0))
end
function tmp = code(x, y)
	tmp = (x ^ 4.0) - (y ^ 4.0);
end
code[x_, y_] := N[(N[Power[x, 4.0], $MachinePrecision] - N[Power[y, 4.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{x}^{4} - {y}^{4}
\end{array}

Alternative 1: 99.8% accurate, 13.7× speedup?

\[\begin{array}{l} \\ \left(x \cdot x + y \cdot y\right) \cdot \left(\left(x - y\right) \cdot \left(x + y\right)\right) \end{array} \]
(FPCore (x y) :precision binary64 (* (+ (* x x) (* y y)) (* (- x y) (+ x y))))
double code(double x, double y) {
	return ((x * x) + (y * y)) * ((x - y) * (x + y));
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * x) + (y * y)) * ((x - y) * (x + y))
end function
public static double code(double x, double y) {
	return ((x * x) + (y * y)) * ((x - y) * (x + y));
}
def code(x, y):
	return ((x * x) + (y * y)) * ((x - y) * (x + y))
function code(x, y)
	return Float64(Float64(Float64(x * x) + Float64(y * y)) * Float64(Float64(x - y) * Float64(x + y)))
end
function tmp = code(x, y)
	tmp = ((x * x) + (y * y)) * ((x - y) * (x + y));
end
code[x_, y_] := N[(N[(N[(x * x), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision] * N[(N[(x - y), $MachinePrecision] * N[(x + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x + y \cdot y\right) \cdot \left(\left(x - y\right) \cdot \left(x + y\right)\right)
\end{array}
Derivation
  1. Initial program 82.0%

    \[{x}^{4} - {y}^{4} \]
  2. Step-by-step derivation
    1. sqr-pow81.9%

      \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
    2. sqr-pow81.9%

      \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
    3. difference-of-squares88.5%

      \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
    4. metadata-eval88.5%

      \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    5. pow288.5%

      \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    6. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    7. pow288.5%

      \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    8. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    9. pow288.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    10. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
    11. pow288.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
  3. Applied egg-rr88.5%

    \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
  4. Step-by-step derivation
    1. difference-of-squares99.8%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \color{blue}{\left(\left(x + y\right) \cdot \left(x - y\right)\right)} \]
    2. *-commutative99.8%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \color{blue}{\left(\left(x - y\right) \cdot \left(x + y\right)\right)} \]
  5. Applied egg-rr99.8%

    \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \color{blue}{\left(\left(x - y\right) \cdot \left(x + y\right)\right)} \]
  6. Final simplification99.8%

    \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\left(x - y\right) \cdot \left(x + y\right)\right) \]

Alternative 2: 73.5% accurate, 13.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq 8.3 \cdot 10^{-69}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(x \cdot x + y \cdot y\right)\\ \mathbf{elif}\;y \leq 1.15 \cdot 10^{+139}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y 8.3e-69)
   (* (* x x) (+ (* x x) (* y y)))
   (if (<= y 1.15e+139)
     (* (* y y) (- (* x x) (* y y)))
     (* (* y y) (* y (- y))))))
double code(double x, double y) {
	double tmp;
	if (y <= 8.3e-69) {
		tmp = (x * x) * ((x * x) + (y * y));
	} else if (y <= 1.15e+139) {
		tmp = (y * y) * ((x * x) - (y * y));
	} else {
		tmp = (y * y) * (y * -y);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= 8.3d-69) then
        tmp = (x * x) * ((x * x) + (y * y))
    else if (y <= 1.15d+139) then
        tmp = (y * y) * ((x * x) - (y * y))
    else
        tmp = (y * y) * (y * -y)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= 8.3e-69) {
		tmp = (x * x) * ((x * x) + (y * y));
	} else if (y <= 1.15e+139) {
		tmp = (y * y) * ((x * x) - (y * y));
	} else {
		tmp = (y * y) * (y * -y);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= 8.3e-69:
		tmp = (x * x) * ((x * x) + (y * y))
	elif y <= 1.15e+139:
		tmp = (y * y) * ((x * x) - (y * y))
	else:
		tmp = (y * y) * (y * -y)
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= 8.3e-69)
		tmp = Float64(Float64(x * x) * Float64(Float64(x * x) + Float64(y * y)));
	elseif (y <= 1.15e+139)
		tmp = Float64(Float64(y * y) * Float64(Float64(x * x) - Float64(y * y)));
	else
		tmp = Float64(Float64(y * y) * Float64(y * Float64(-y)));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= 8.3e-69)
		tmp = (x * x) * ((x * x) + (y * y));
	elseif (y <= 1.15e+139)
		tmp = (y * y) * ((x * x) - (y * y));
	else
		tmp = (y * y) * (y * -y);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, 8.3e-69], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.15e+139], N[(N[(y * y), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] - N[(y * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(y * y), $MachinePrecision] * N[(y * (-y)), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq 8.3 \cdot 10^{-69}:\\
\;\;\;\;\left(x \cdot x\right) \cdot \left(x \cdot x + y \cdot y\right)\\

\mathbf{elif}\;y \leq 1.15 \cdot 10^{+139}:\\
\;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\

\mathbf{else}:\\
\;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < 8.3000000000000004e-69

    1. Initial program 88.9%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow88.7%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow88.7%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares94.0%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval94.0%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow294.0%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval94.0%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow294.0%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval94.0%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow294.0%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval94.0%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow294.0%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr94.0%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around inf 73.6%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \color{blue}{{x}^{2}} \]
    5. Step-by-step derivation
      1. unpow273.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    6. Simplified73.6%

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

    if 8.3000000000000004e-69 < y < 1.15e139

    1. Initial program 87.5%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow87.4%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow87.1%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares99.6%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval99.6%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow299.6%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval99.6%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow299.6%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval99.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow299.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval99.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow299.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 88.0%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow288.0%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified88.0%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]

    if 1.15e139 < y

    1. Initial program 48.8%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow48.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow48.8%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares58.1%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval58.1%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow258.1%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval58.1%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow258.1%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval58.1%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow258.1%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval58.1%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow258.1%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr58.1%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 58.1%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow258.1%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified58.1%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    7. Taylor expanded in x around 0 76.7%

      \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(-1 \cdot {y}^{2}\right)} \]
    8. Step-by-step derivation
      1. unpow276.7%

        \[\leadsto \left(y \cdot y\right) \cdot \left(-1 \cdot \color{blue}{\left(y \cdot y\right)}\right) \]
      2. mul-1-neg76.7%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(-y \cdot y\right)} \]
      3. distribute-rgt-neg-out76.7%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(y \cdot \left(-y\right)\right)} \]
    9. Simplified76.7%

      \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(y \cdot \left(-y\right)\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification75.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq 8.3 \cdot 10^{-69}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(x \cdot x + y \cdot y\right)\\ \mathbf{elif}\;y \leq 1.15 \cdot 10^{+139}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\ \end{array} \]

Alternative 3: 61.7% accurate, 14.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.5 \cdot 10^{+170} \lor \neg \left(x \leq 6.4 \cdot 10^{+179}\right) \land x \leq 4.2 \cdot 10^{+221}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x 1.5e+170) (and (not (<= x 6.4e+179)) (<= x 4.2e+221)))
   (* (* y y) (* y (- y)))
   (* (* x x) (* y y))))
double code(double x, double y) {
	double tmp;
	if ((x <= 1.5e+170) || (!(x <= 6.4e+179) && (x <= 4.2e+221))) {
		tmp = (y * y) * (y * -y);
	} else {
		tmp = (x * x) * (y * y);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= 1.5d+170) .or. (.not. (x <= 6.4d+179)) .and. (x <= 4.2d+221)) then
        tmp = (y * y) * (y * -y)
    else
        tmp = (x * x) * (y * y)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= 1.5e+170) || (!(x <= 6.4e+179) && (x <= 4.2e+221))) {
		tmp = (y * y) * (y * -y);
	} else {
		tmp = (x * x) * (y * y);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= 1.5e+170) or (not (x <= 6.4e+179) and (x <= 4.2e+221)):
		tmp = (y * y) * (y * -y)
	else:
		tmp = (x * x) * (y * y)
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= 1.5e+170) || (!(x <= 6.4e+179) && (x <= 4.2e+221)))
		tmp = Float64(Float64(y * y) * Float64(y * Float64(-y)));
	else
		tmp = Float64(Float64(x * x) * Float64(y * y));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= 1.5e+170) || (~((x <= 6.4e+179)) && (x <= 4.2e+221)))
		tmp = (y * y) * (y * -y);
	else
		tmp = (x * x) * (y * y);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, 1.5e+170], And[N[Not[LessEqual[x, 6.4e+179]], $MachinePrecision], LessEqual[x, 4.2e+221]]], N[(N[(y * y), $MachinePrecision] * N[(y * (-y)), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * N[(y * y), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.5 \cdot 10^{+170} \lor \neg \left(x \leq 6.4 \cdot 10^{+179}\right) \land x \leq 4.2 \cdot 10^{+221}:\\
\;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.49999999999999998e170 or 6.4000000000000003e179 < x < 4.20000000000000004e221

    1. Initial program 83.3%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow83.1%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow83.1%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares89.8%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval89.8%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow289.8%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval89.8%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow289.8%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval89.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow289.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval89.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow289.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr89.8%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 65.5%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow265.5%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified65.5%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    7. Taylor expanded in x around 0 62.9%

      \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(-1 \cdot {y}^{2}\right)} \]
    8. Step-by-step derivation
      1. unpow262.9%

        \[\leadsto \left(y \cdot y\right) \cdot \left(-1 \cdot \color{blue}{\left(y \cdot y\right)}\right) \]
      2. mul-1-neg62.9%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(-y \cdot y\right)} \]
      3. distribute-rgt-neg-out62.9%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(y \cdot \left(-y\right)\right)} \]
    9. Simplified62.9%

      \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(y \cdot \left(-y\right)\right)} \]

    if 1.49999999999999998e170 < x < 6.4000000000000003e179 or 4.20000000000000004e221 < x

    1. Initial program 64.7%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow64.7%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow64.7%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares70.6%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval70.6%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow270.6%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval70.6%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow270.6%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval70.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow270.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval70.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow270.6%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr70.6%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 52.9%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow252.9%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified52.9%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    7. Taylor expanded in y around 0 82.4%

      \[\leadsto \color{blue}{{y}^{2} \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. unpow282.4%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot {x}^{2} \]
      2. unpow282.4%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    9. Simplified82.4%

      \[\leadsto \color{blue}{\left(y \cdot y\right) \cdot \left(x \cdot x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.5 \cdot 10^{+170} \lor \neg \left(x \leq 6.4 \cdot 10^{+179}\right) \land x \leq 4.2 \cdot 10^{+221}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(y \cdot \left(-y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\ \end{array} \]

Alternative 4: 70.2% accurate, 15.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.35 \cdot 10^{+154}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x 1.35e+154) (* (* y y) (- (* x x) (* y y))) (* (* x x) (* y y))))
double code(double x, double y) {
	double tmp;
	if (x <= 1.35e+154) {
		tmp = (y * y) * ((x * x) - (y * y));
	} else {
		tmp = (x * x) * (y * y);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= 1.35d+154) then
        tmp = (y * y) * ((x * x) - (y * y))
    else
        tmp = (x * x) * (y * y)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= 1.35e+154) {
		tmp = (y * y) * ((x * x) - (y * y));
	} else {
		tmp = (x * x) * (y * y);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= 1.35e+154:
		tmp = (y * y) * ((x * x) - (y * y))
	else:
		tmp = (x * x) * (y * y)
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= 1.35e+154)
		tmp = Float64(Float64(y * y) * Float64(Float64(x * x) - Float64(y * y)));
	else
		tmp = Float64(Float64(x * x) * Float64(y * y));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= 1.35e+154)
		tmp = (y * y) * ((x * x) - (y * y));
	else
		tmp = (x * x) * (y * y);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, 1.35e+154], N[(N[(y * y), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] - N[(y * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * N[(y * y), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.35 \cdot 10^{+154}:\\
\;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.35000000000000003e154

    1. Initial program 84.1%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow84.0%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow83.9%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares90.8%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval90.8%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow290.8%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval90.8%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow290.8%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval90.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow290.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval90.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow290.8%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr90.8%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 67.1%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow267.1%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified67.1%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]

    if 1.35000000000000003e154 < x

    1. Initial program 60.9%

      \[{x}^{4} - {y}^{4} \]
    2. Step-by-step derivation
      1. sqr-pow60.9%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
      2. sqr-pow60.9%

        \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
      3. difference-of-squares65.2%

        \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
      4. metadata-eval65.2%

        \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      5. pow265.2%

        \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      6. metadata-eval65.2%

        \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      7. pow265.2%

        \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      8. metadata-eval65.2%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      9. pow265.2%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
      10. metadata-eval65.2%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
      11. pow265.2%

        \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
    3. Applied egg-rr65.2%

      \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
    4. Taylor expanded in x around 0 39.1%

      \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
    5. Step-by-step derivation
      1. unpow239.1%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    6. Simplified39.1%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
    7. Taylor expanded in y around 0 60.9%

      \[\leadsto \color{blue}{{y}^{2} \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. unpow260.9%

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot {x}^{2} \]
      2. unpow260.9%

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    9. Simplified60.9%

      \[\leadsto \color{blue}{\left(y \cdot y\right) \cdot \left(x \cdot x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification66.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.35 \cdot 10^{+154}:\\ \;\;\;\;\left(y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot \left(y \cdot y\right)\\ \end{array} \]

Alternative 5: 32.8% accurate, 29.3× speedup?

\[\begin{array}{l} \\ \left(x \cdot x\right) \cdot \left(y \cdot y\right) \end{array} \]
(FPCore (x y) :precision binary64 (* (* x x) (* y y)))
double code(double x, double y) {
	return (x * x) * (y * y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x * x) * (y * y)
end function
public static double code(double x, double y) {
	return (x * x) * (y * y);
}
def code(x, y):
	return (x * x) * (y * y)
function code(x, y)
	return Float64(Float64(x * x) * Float64(y * y))
end
function tmp = code(x, y)
	tmp = (x * x) * (y * y);
end
code[x_, y_] := N[(N[(x * x), $MachinePrecision] * N[(y * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot x\right) \cdot \left(y \cdot y\right)
\end{array}
Derivation
  1. Initial program 82.0%

    \[{x}^{4} - {y}^{4} \]
  2. Step-by-step derivation
    1. sqr-pow81.9%

      \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)}} - {y}^{4} \]
    2. sqr-pow81.9%

      \[\leadsto {x}^{\left(\frac{4}{2}\right)} \cdot {x}^{\left(\frac{4}{2}\right)} - \color{blue}{{y}^{\left(\frac{4}{2}\right)} \cdot {y}^{\left(\frac{4}{2}\right)}} \]
    3. difference-of-squares88.5%

      \[\leadsto \color{blue}{\left({x}^{\left(\frac{4}{2}\right)} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right)} \]
    4. metadata-eval88.5%

      \[\leadsto \left({x}^{\color{blue}{2}} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    5. pow288.5%

      \[\leadsto \left(\color{blue}{x \cdot x} + {y}^{\left(\frac{4}{2}\right)}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    6. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + {y}^{\color{blue}{2}}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    7. pow288.5%

      \[\leadsto \left(x \cdot x + \color{blue}{y \cdot y}\right) \cdot \left({x}^{\left(\frac{4}{2}\right)} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    8. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left({x}^{\color{blue}{2}} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    9. pow288.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(\color{blue}{x \cdot x} - {y}^{\left(\frac{4}{2}\right)}\right) \]
    10. metadata-eval88.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - {y}^{\color{blue}{2}}\right) \]
    11. pow288.5%

      \[\leadsto \left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - \color{blue}{y \cdot y}\right) \]
  3. Applied egg-rr88.5%

    \[\leadsto \color{blue}{\left(x \cdot x + y \cdot y\right) \cdot \left(x \cdot x - y \cdot y\right)} \]
  4. Taylor expanded in x around 0 64.6%

    \[\leadsto \color{blue}{{y}^{2}} \cdot \left(x \cdot x - y \cdot y\right) \]
  5. Step-by-step derivation
    1. unpow264.6%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
  6. Simplified64.6%

    \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \left(x \cdot x - y \cdot y\right) \]
  7. Taylor expanded in y around 0 38.0%

    \[\leadsto \color{blue}{{y}^{2} \cdot {x}^{2}} \]
  8. Step-by-step derivation
    1. unpow238.0%

      \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot {x}^{2} \]
    2. unpow238.0%

      \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
  9. Simplified38.0%

    \[\leadsto \color{blue}{\left(y \cdot y\right) \cdot \left(x \cdot x\right)} \]
  10. Final simplification38.0%

    \[\leadsto \left(x \cdot x\right) \cdot \left(y \cdot y\right) \]

Reproduce

?
herbie shell --seed 2023238 
(FPCore (x y)
  :name "Radioactive exchange between two surfaces"
  :precision binary64
  (- (pow x 4.0) (pow y 4.0)))