Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, H

Percentage Accurate: 99.9% → 99.9%
Time: 4.7s
Alternatives: 6
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{x \cdot x - 3}{6} \end{array} \]
(FPCore (x) :precision binary64 (/ (- (* x x) 3.0) 6.0))
double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((x * x) - 3.0d0) / 6.0d0
end function
public static double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
def code(x):
	return ((x * x) - 3.0) / 6.0
function code(x)
	return Float64(Float64(Float64(x * x) - 3.0) / 6.0)
end
function tmp = code(x)
	tmp = ((x * x) - 3.0) / 6.0;
end
code[x_] := N[(N[(N[(x * x), $MachinePrecision] - 3.0), $MachinePrecision] / 6.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{x \cdot x - 3}{6}
\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 6 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: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x \cdot x - 3}{6} \end{array} \]
(FPCore (x) :precision binary64 (/ (- (* x x) 3.0) 6.0))
double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((x * x) - 3.0d0) / 6.0d0
end function
public static double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
def code(x):
	return ((x * x) - 3.0) / 6.0
function code(x)
	return Float64(Float64(Float64(x * x) - 3.0) / 6.0)
end
function tmp = code(x)
	tmp = ((x * x) - 3.0) / 6.0;
end
code[x_] := N[(N[(N[(x * x), $MachinePrecision] - 3.0), $MachinePrecision] / 6.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{x \cdot x - 3}{6}
\end{array}

Alternative 1: 99.9% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(0.16666666666666666 \cdot x, x, -0.5\right) \end{array} \]
(FPCore (x) :precision binary64 (fma (* 0.16666666666666666 x) x -0.5))
double code(double x) {
	return fma((0.16666666666666666 * x), x, -0.5);
}
function code(x)
	return fma(Float64(0.16666666666666666 * x), x, -0.5)
end
code[x_] := N[(N[(0.16666666666666666 * x), $MachinePrecision] * x + -0.5), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(0.16666666666666666 \cdot x, x, -0.5\right)
\end{array}
Derivation
  1. Initial program 99.8%

    \[\frac{x \cdot x - 3}{6} \]
  2. Step-by-step derivation
    1. sqr-neg99.8%

      \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
    2. *-lft-identity99.8%

      \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
    3. metadata-eval99.8%

      \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
    4. associate-*r/99.8%

      \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
    5. associate-/l*99.8%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
    6. associate-/r/99.8%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
    7. *-commutative99.8%

      \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
    8. sqr-neg99.8%

      \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
    9. fma-neg99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
    10. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
    11. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
    12. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
  3. Simplified99.8%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
  4. Step-by-step derivation
    1. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot 0.16666666666666666 \]
    2. fma-neg99.8%

      \[\leadsto \color{blue}{\left(x \cdot x - 3\right)} \cdot 0.16666666666666666 \]
    3. metadata-eval99.8%

      \[\leadsto \left(x \cdot x - 3\right) \cdot \color{blue}{\frac{1}{6}} \]
    4. div-inv99.8%

      \[\leadsto \color{blue}{\frac{x \cdot x - 3}{6}} \]
    5. clear-num99.8%

      \[\leadsto \color{blue}{\frac{1}{\frac{6}{x \cdot x - 3}}} \]
    6. fma-neg99.8%

      \[\leadsto \frac{1}{\frac{6}{\color{blue}{\mathsf{fma}\left(x, x, -3\right)}}} \]
    7. metadata-eval99.8%

      \[\leadsto \frac{1}{\frac{6}{\mathsf{fma}\left(x, x, \color{blue}{-3}\right)}} \]
  5. Applied egg-rr99.8%

    \[\leadsto \color{blue}{\frac{1}{\frac{6}{\mathsf{fma}\left(x, x, -3\right)}}} \]
  6. Step-by-step derivation
    1. clear-num99.8%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\mathsf{fma}\left(x, x, -3\right)}{6}}}} \]
    2. associate-/r/99.8%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\mathsf{fma}\left(x, x, -3\right)} \cdot 6}} \]
  7. Applied egg-rr99.8%

    \[\leadsto \frac{1}{\color{blue}{\frac{1}{\mathsf{fma}\left(x, x, -3\right)} \cdot 6}} \]
  8. Step-by-step derivation
    1. associate-*l/99.8%

      \[\leadsto \frac{1}{\color{blue}{\frac{1 \cdot 6}{\mathsf{fma}\left(x, x, -3\right)}}} \]
    2. metadata-eval99.8%

      \[\leadsto \frac{1}{\frac{\color{blue}{6}}{\mathsf{fma}\left(x, x, -3\right)}} \]
    3. associate-/r/99.8%

      \[\leadsto \color{blue}{\frac{1}{6} \cdot \mathsf{fma}\left(x, x, -3\right)} \]
    4. metadata-eval99.8%

      \[\leadsto \color{blue}{0.16666666666666666} \cdot \mathsf{fma}\left(x, x, -3\right) \]
    5. fma-udef99.8%

      \[\leadsto 0.16666666666666666 \cdot \color{blue}{\left(x \cdot x + -3\right)} \]
    6. unpow299.8%

      \[\leadsto 0.16666666666666666 \cdot \left(\color{blue}{{x}^{2}} + -3\right) \]
    7. distribute-lft-in99.8%

      \[\leadsto \color{blue}{0.16666666666666666 \cdot {x}^{2} + 0.16666666666666666 \cdot -3} \]
    8. unpow299.8%

      \[\leadsto 0.16666666666666666 \cdot \color{blue}{\left(x \cdot x\right)} + 0.16666666666666666 \cdot -3 \]
    9. associate-*r*99.8%

      \[\leadsto \color{blue}{\left(0.16666666666666666 \cdot x\right) \cdot x} + 0.16666666666666666 \cdot -3 \]
    10. metadata-eval99.8%

      \[\leadsto \left(0.16666666666666666 \cdot x\right) \cdot x + \color{blue}{-0.5} \]
    11. metadata-eval99.8%

      \[\leadsto \left(0.16666666666666666 \cdot x\right) \cdot x + \color{blue}{\frac{-1}{2}} \]
    12. fma-def99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(0.16666666666666666 \cdot x, x, \frac{-1}{2}\right)} \]
    13. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(0.16666666666666666 \cdot x, x, \color{blue}{-0.5}\right) \]
  9. Applied egg-rr99.8%

    \[\leadsto \color{blue}{\mathsf{fma}\left(0.16666666666666666 \cdot x, x, -0.5\right)} \]
  10. Final simplification99.8%

    \[\leadsto \mathsf{fma}\left(0.16666666666666666 \cdot x, x, -0.5\right) \]

Alternative 2: 73.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(0.16666666666666666 \cdot x\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.75) -0.5 (* x (* 0.16666666666666666 x))))
double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x * (0.16666666666666666 * x);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.75d0) then
        tmp = -0.5d0
    else
        tmp = x * (0.16666666666666666d0 * x)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x * (0.16666666666666666 * x);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.75:
		tmp = -0.5
	else:
		tmp = x * (0.16666666666666666 * x)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = Float64(x * Float64(0.16666666666666666 * x));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = x * (0.16666666666666666 * x);
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.75], -0.5, N[(x * N[(0.16666666666666666 * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.75:\\
\;\;\;\;-0.5\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(0.16666666666666666 \cdot x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.75

    1. Initial program 99.9%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.9%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.9%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.9%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.9%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.8%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.8%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Taylor expanded in x around 0 58.7%

      \[\leadsto \color{blue}{-0.5} \]

    if 1.75 < x

    1. Initial program 99.7%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.7%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.7%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.7%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.7%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.7%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.6%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.6%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Step-by-step derivation
      1. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot 0.16666666666666666 \]
      2. fma-neg99.6%

        \[\leadsto \color{blue}{\left(x \cdot x - 3\right)} \cdot 0.16666666666666666 \]
      3. metadata-eval99.6%

        \[\leadsto \left(x \cdot x - 3\right) \cdot \color{blue}{\frac{1}{6}} \]
      4. div-inv99.7%

        \[\leadsto \color{blue}{\frac{x \cdot x - 3}{6}} \]
      5. clear-num99.7%

        \[\leadsto \color{blue}{\frac{1}{\frac{6}{x \cdot x - 3}}} \]
      6. fma-neg99.7%

        \[\leadsto \frac{1}{\frac{6}{\color{blue}{\mathsf{fma}\left(x, x, -3\right)}}} \]
      7. metadata-eval99.7%

        \[\leadsto \frac{1}{\frac{6}{\mathsf{fma}\left(x, x, \color{blue}{-3}\right)}} \]
    5. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\frac{1}{\frac{6}{\mathsf{fma}\left(x, x, -3\right)}}} \]
    6. Taylor expanded in x around inf 98.9%

      \[\leadsto \frac{1}{\color{blue}{\frac{6}{{x}^{2}}}} \]
    7. Step-by-step derivation
      1. associate-/r/98.9%

        \[\leadsto \color{blue}{\frac{1}{6} \cdot {x}^{2}} \]
      2. metadata-eval98.9%

        \[\leadsto \color{blue}{0.16666666666666666} \cdot {x}^{2} \]
      3. unpow298.9%

        \[\leadsto 0.16666666666666666 \cdot \color{blue}{\left(x \cdot x\right)} \]
      4. associate-*r*99.1%

        \[\leadsto \color{blue}{\left(0.16666666666666666 \cdot x\right) \cdot x} \]
    8. Applied egg-rr99.1%

      \[\leadsto \color{blue}{\left(0.16666666666666666 \cdot x\right) \cdot x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(0.16666666666666666 \cdot x\right)\\ \end{array} \]

Alternative 3: 73.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot \frac{x}{6}\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 1.75) -0.5 (* x (/ x 6.0))))
double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x * (x / 6.0);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.75d0) then
        tmp = -0.5d0
    else
        tmp = x * (x / 6.0d0)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x * (x / 6.0);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.75:
		tmp = -0.5
	else:
		tmp = x * (x / 6.0)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = Float64(x * Float64(x / 6.0));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = x * (x / 6.0);
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.75], -0.5, N[(x * N[(x / 6.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.75:\\
\;\;\;\;-0.5\\

\mathbf{else}:\\
\;\;\;\;x \cdot \frac{x}{6}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.75

    1. Initial program 99.9%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.9%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.9%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.9%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.9%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.8%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.8%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Taylor expanded in x around 0 58.7%

      \[\leadsto \color{blue}{-0.5} \]

    if 1.75 < x

    1. Initial program 99.7%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.7%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.7%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.7%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.7%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.7%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.6%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.6%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Taylor expanded in x around inf 98.9%

      \[\leadsto \color{blue}{0.16666666666666666 \cdot {x}^{2}} \]
    5. Step-by-step derivation
      1. rem-exp-log98.6%

        \[\leadsto \color{blue}{e^{\log 0.16666666666666666}} \cdot {x}^{2} \]
      2. add-sqr-sqrt98.6%

        \[\leadsto \color{blue}{\sqrt{e^{\log 0.16666666666666666} \cdot {x}^{2}} \cdot \sqrt{e^{\log 0.16666666666666666} \cdot {x}^{2}}} \]
      3. sqrt-unprod69.7%

        \[\leadsto \color{blue}{\sqrt{\left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right) \cdot \left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right)}} \]
      4. *-commutative69.7%

        \[\leadsto \sqrt{\color{blue}{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right)} \cdot \left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right)} \]
      5. *-commutative69.7%

        \[\leadsto \sqrt{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right) \cdot \color{blue}{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right)}} \]
      6. swap-sqr69.8%

        \[\leadsto \sqrt{\color{blue}{\left({x}^{2} \cdot {x}^{2}\right) \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)}} \]
      7. pow-prod-up69.8%

        \[\leadsto \sqrt{\color{blue}{{x}^{\left(2 + 2\right)}} \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      8. metadata-eval69.8%

        \[\leadsto \sqrt{{x}^{\color{blue}{4}} \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      9. rem-exp-log69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \left(\color{blue}{0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      10. rem-exp-log69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \left(0.16666666666666666 \cdot \color{blue}{0.16666666666666666}\right)} \]
      11. metadata-eval69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \color{blue}{0.027777777777777776}} \]
    6. Applied egg-rr69.9%

      \[\leadsto \color{blue}{\sqrt{{x}^{4} \cdot 0.027777777777777776}} \]
    7. Step-by-step derivation
      1. sqrt-prod69.9%

        \[\leadsto \color{blue}{\sqrt{{x}^{4}} \cdot \sqrt{0.027777777777777776}} \]
      2. metadata-eval69.9%

        \[\leadsto \sqrt{{x}^{4}} \cdot \color{blue}{0.16666666666666666} \]
      3. sqrt-pow198.9%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)}} \cdot 0.16666666666666666 \]
      4. metadata-eval98.9%

        \[\leadsto {x}^{\color{blue}{2}} \cdot 0.16666666666666666 \]
      5. metadata-eval98.9%

        \[\leadsto {x}^{2} \cdot \color{blue}{\frac{1}{6}} \]
      6. div-inv99.0%

        \[\leadsto \color{blue}{\frac{{x}^{2}}{6}} \]
      7. unpow299.0%

        \[\leadsto \frac{\color{blue}{x \cdot x}}{6} \]
      8. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{x}{\frac{6}{x}}} \]
    8. Applied egg-rr99.0%

      \[\leadsto \color{blue}{\frac{x}{\frac{6}{x}}} \]
    9. Step-by-step derivation
      1. associate-/r/99.1%

        \[\leadsto \color{blue}{\frac{x}{6} \cdot x} \]
    10. Simplified99.1%

      \[\leadsto \color{blue}{\frac{x}{6} \cdot x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot \frac{x}{6}\\ \end{array} \]

Alternative 4: 73.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{\frac{6}{x}}\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 1.75) -0.5 (/ x (/ 6.0 x))))
double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x / (6.0 / x);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.75d0) then
        tmp = -0.5d0
    else
        tmp = x / (6.0d0 / x)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.75) {
		tmp = -0.5;
	} else {
		tmp = x / (6.0 / x);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.75:
		tmp = -0.5
	else:
		tmp = x / (6.0 / x)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = Float64(x / Float64(6.0 / x));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.75)
		tmp = -0.5;
	else
		tmp = x / (6.0 / x);
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.75], -0.5, N[(x / N[(6.0 / x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.75:\\
\;\;\;\;-0.5\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{\frac{6}{x}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.75

    1. Initial program 99.9%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.9%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.9%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.9%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.9%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.8%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.8%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.8%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Taylor expanded in x around 0 58.7%

      \[\leadsto \color{blue}{-0.5} \]

    if 1.75 < x

    1. Initial program 99.7%

      \[\frac{x \cdot x - 3}{6} \]
    2. Step-by-step derivation
      1. sqr-neg99.7%

        \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
      2. *-lft-identity99.7%

        \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
      3. metadata-eval99.7%

        \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
      4. associate-*r/99.7%

        \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
      5. associate-/l*99.7%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
      6. associate-/r/99.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
      7. *-commutative99.6%

        \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
      8. sqr-neg99.6%

        \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
      9. fma-neg99.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
      10. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
      11. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
      12. metadata-eval99.6%

        \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
    4. Taylor expanded in x around inf 98.9%

      \[\leadsto \color{blue}{0.16666666666666666 \cdot {x}^{2}} \]
    5. Step-by-step derivation
      1. rem-exp-log98.6%

        \[\leadsto \color{blue}{e^{\log 0.16666666666666666}} \cdot {x}^{2} \]
      2. add-sqr-sqrt98.6%

        \[\leadsto \color{blue}{\sqrt{e^{\log 0.16666666666666666} \cdot {x}^{2}} \cdot \sqrt{e^{\log 0.16666666666666666} \cdot {x}^{2}}} \]
      3. sqrt-unprod69.7%

        \[\leadsto \color{blue}{\sqrt{\left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right) \cdot \left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right)}} \]
      4. *-commutative69.7%

        \[\leadsto \sqrt{\color{blue}{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right)} \cdot \left(e^{\log 0.16666666666666666} \cdot {x}^{2}\right)} \]
      5. *-commutative69.7%

        \[\leadsto \sqrt{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right) \cdot \color{blue}{\left({x}^{2} \cdot e^{\log 0.16666666666666666}\right)}} \]
      6. swap-sqr69.8%

        \[\leadsto \sqrt{\color{blue}{\left({x}^{2} \cdot {x}^{2}\right) \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)}} \]
      7. pow-prod-up69.8%

        \[\leadsto \sqrt{\color{blue}{{x}^{\left(2 + 2\right)}} \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      8. metadata-eval69.8%

        \[\leadsto \sqrt{{x}^{\color{blue}{4}} \cdot \left(e^{\log 0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      9. rem-exp-log69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \left(\color{blue}{0.16666666666666666} \cdot e^{\log 0.16666666666666666}\right)} \]
      10. rem-exp-log69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \left(0.16666666666666666 \cdot \color{blue}{0.16666666666666666}\right)} \]
      11. metadata-eval69.9%

        \[\leadsto \sqrt{{x}^{4} \cdot \color{blue}{0.027777777777777776}} \]
    6. Applied egg-rr69.9%

      \[\leadsto \color{blue}{\sqrt{{x}^{4} \cdot 0.027777777777777776}} \]
    7. Step-by-step derivation
      1. sqrt-prod69.9%

        \[\leadsto \color{blue}{\sqrt{{x}^{4}} \cdot \sqrt{0.027777777777777776}} \]
      2. metadata-eval69.9%

        \[\leadsto \sqrt{{x}^{4}} \cdot \color{blue}{0.16666666666666666} \]
      3. sqrt-pow198.9%

        \[\leadsto \color{blue}{{x}^{\left(\frac{4}{2}\right)}} \cdot 0.16666666666666666 \]
      4. metadata-eval98.9%

        \[\leadsto {x}^{\color{blue}{2}} \cdot 0.16666666666666666 \]
      5. metadata-eval98.9%

        \[\leadsto {x}^{2} \cdot \color{blue}{\frac{1}{6}} \]
      6. div-inv99.0%

        \[\leadsto \color{blue}{\frac{{x}^{2}}{6}} \]
      7. unpow299.0%

        \[\leadsto \frac{\color{blue}{x \cdot x}}{6} \]
      8. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{x}{\frac{6}{x}}} \]
    8. Applied egg-rr99.0%

      \[\leadsto \color{blue}{\frac{x}{\frac{6}{x}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.75:\\ \;\;\;\;-0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{\frac{6}{x}}\\ \end{array} \]

Alternative 5: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x \cdot x - 3}{6} \end{array} \]
(FPCore (x) :precision binary64 (/ (- (* x x) 3.0) 6.0))
double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = ((x * x) - 3.0d0) / 6.0d0
end function
public static double code(double x) {
	return ((x * x) - 3.0) / 6.0;
}
def code(x):
	return ((x * x) - 3.0) / 6.0
function code(x)
	return Float64(Float64(Float64(x * x) - 3.0) / 6.0)
end
function tmp = code(x)
	tmp = ((x * x) - 3.0) / 6.0;
end
code[x_] := N[(N[(N[(x * x), $MachinePrecision] - 3.0), $MachinePrecision] / 6.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{x \cdot x - 3}{6}
\end{array}
Derivation
  1. Initial program 99.8%

    \[\frac{x \cdot x - 3}{6} \]
  2. Final simplification99.8%

    \[\leadsto \frac{x \cdot x - 3}{6} \]

Alternative 6: 49.3% accurate, 7.0× speedup?

\[\begin{array}{l} \\ -0.5 \end{array} \]
(FPCore (x) :precision binary64 -0.5)
double code(double x) {
	return -0.5;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = -0.5d0
end function
public static double code(double x) {
	return -0.5;
}
def code(x):
	return -0.5
function code(x)
	return -0.5
end
function tmp = code(x)
	tmp = -0.5;
end
code[x_] := -0.5
\begin{array}{l}

\\
-0.5
\end{array}
Derivation
  1. Initial program 99.8%

    \[\frac{x \cdot x - 3}{6} \]
  2. Step-by-step derivation
    1. sqr-neg99.8%

      \[\leadsto \frac{\color{blue}{\left(-x\right) \cdot \left(-x\right)} - 3}{6} \]
    2. *-lft-identity99.8%

      \[\leadsto \color{blue}{1 \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6}} \]
    3. metadata-eval99.8%

      \[\leadsto \color{blue}{\left(-1 \cdot -1\right)} \cdot \frac{\left(-x\right) \cdot \left(-x\right) - 3}{6} \]
    4. associate-*r/99.8%

      \[\leadsto \color{blue}{\frac{\left(-1 \cdot -1\right) \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)}{6}} \]
    5. associate-/l*99.8%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1}{\frac{6}{\left(-x\right) \cdot \left(-x\right) - 3}}} \]
    6. associate-/r/99.8%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1}{6} \cdot \left(\left(-x\right) \cdot \left(-x\right) - 3\right)} \]
    7. *-commutative99.8%

      \[\leadsto \color{blue}{\left(\left(-x\right) \cdot \left(-x\right) - 3\right) \cdot \frac{-1 \cdot -1}{6}} \]
    8. sqr-neg99.8%

      \[\leadsto \left(\color{blue}{x \cdot x} - 3\right) \cdot \frac{-1 \cdot -1}{6} \]
    9. fma-neg99.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right)} \cdot \frac{-1 \cdot -1}{6} \]
    10. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, \color{blue}{-3}\right) \cdot \frac{-1 \cdot -1}{6} \]
    11. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \frac{\color{blue}{1}}{6} \]
    12. metadata-eval99.8%

      \[\leadsto \mathsf{fma}\left(x, x, -3\right) \cdot \color{blue}{0.16666666666666666} \]
  3. Simplified99.8%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, -3\right) \cdot 0.16666666666666666} \]
  4. Taylor expanded in x around 0 43.5%

    \[\leadsto \color{blue}{-0.5} \]
  5. Final simplification43.5%

    \[\leadsto -0.5 \]

Reproduce

?
herbie shell --seed 2023336 
(FPCore (x)
  :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, H"
  :precision binary64
  (/ (- (* x x) 3.0) 6.0))