Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, A

Percentage Accurate: 99.9% → 99.7%
Time: 5.2s
Alternatives: 9
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ 1 - x \cdot \left(0.253 + x \cdot 0.12\right) \end{array} \]
(FPCore (x) :precision binary64 (- 1.0 (* x (+ 0.253 (* x 0.12)))))
double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - (x * (0.253d0 + (x * 0.12d0)))
end function
public static double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
def code(x):
	return 1.0 - (x * (0.253 + (x * 0.12)))
function code(x)
	return Float64(1.0 - Float64(x * Float64(0.253 + Float64(x * 0.12))))
end
function tmp = code(x)
	tmp = 1.0 - (x * (0.253 + (x * 0.12)));
end
code[x_] := N[(1.0 - N[(x * N[(0.253 + N[(x * 0.12), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - x \cdot \left(0.253 + x \cdot 0.12\right)
\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 9 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?

\[\begin{array}{l} \\ 1 - x \cdot \left(0.253 + x \cdot 0.12\right) \end{array} \]
(FPCore (x) :precision binary64 (- 1.0 (* x (+ 0.253 (* x 0.12)))))
double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - (x * (0.253d0 + (x * 0.12d0)))
end function
public static double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
def code(x):
	return 1.0 - (x * (0.253 + (x * 0.12)))
function code(x)
	return Float64(1.0 - Float64(x * Float64(0.253 + Float64(x * 0.12))))
end
function tmp = code(x)
	tmp = 1.0 - (x * (0.253 + (x * 0.12)));
end
code[x_] := N[(1.0 - N[(x * N[(0.253 + N[(x * 0.12), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - x \cdot \left(0.253 + x \cdot 0.12\right)
\end{array}

Alternative 1: 99.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ 1 - \left(x \cdot 0.253 + 0.12 \cdot \left(x \cdot x\right)\right) \end{array} \]
(FPCore (x) :precision binary64 (- 1.0 (+ (* x 0.253) (* 0.12 (* x x)))))
double code(double x) {
	return 1.0 - ((x * 0.253) + (0.12 * (x * x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - ((x * 0.253d0) + (0.12d0 * (x * x)))
end function
public static double code(double x) {
	return 1.0 - ((x * 0.253) + (0.12 * (x * x)));
}
def code(x):
	return 1.0 - ((x * 0.253) + (0.12 * (x * x)))
function code(x)
	return Float64(1.0 - Float64(Float64(x * 0.253) + Float64(0.12 * Float64(x * x))))
end
function tmp = code(x)
	tmp = 1.0 - ((x * 0.253) + (0.12 * (x * x)));
end
code[x_] := N[(1.0 - N[(N[(x * 0.253), $MachinePrecision] + N[(0.12 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - \left(x \cdot 0.253 + 0.12 \cdot \left(x \cdot x\right)\right)
\end{array}
Derivation
  1. Initial program 99.9%

    \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
  2. Step-by-step derivation
    1. distribute-rgt-in99.9%

      \[\leadsto 1 - \color{blue}{\left(0.253 \cdot x + \left(x \cdot 0.12\right) \cdot x\right)} \]
    2. *-commutative99.9%

      \[\leadsto 1 - \left(\color{blue}{x \cdot 0.253} + \left(x \cdot 0.12\right) \cdot x\right) \]
    3. *-commutative99.9%

      \[\leadsto 1 - \left(x \cdot 0.253 + \color{blue}{\left(0.12 \cdot x\right)} \cdot x\right) \]
    4. associate-*l*99.9%

      \[\leadsto 1 - \left(x \cdot 0.253 + \color{blue}{0.12 \cdot \left(x \cdot x\right)}\right) \]
  3. Applied egg-rr99.9%

    \[\leadsto 1 - \color{blue}{\left(x \cdot 0.253 + 0.12 \cdot \left(x \cdot x\right)\right)} \]
  4. Final simplification99.9%

    \[\leadsto 1 - \left(x \cdot 0.253 + 0.12 \cdot \left(x \cdot x\right)\right) \]

Alternative 2: 59.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4 \lor \neg \left(x \leq 2.05\right):\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{else}:\\ \;\;\;\;1.5334083333333333\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (or (<= x -4.0) (not (<= x 2.05))) (* x (* x -0.12)) 1.5334083333333333))
double code(double x) {
	double tmp;
	if ((x <= -4.0) || !(x <= 2.05)) {
		tmp = x * (x * -0.12);
	} else {
		tmp = 1.5334083333333333;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if ((x <= (-4.0d0)) .or. (.not. (x <= 2.05d0))) then
        tmp = x * (x * (-0.12d0))
    else
        tmp = 1.5334083333333333d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if ((x <= -4.0) || !(x <= 2.05)) {
		tmp = x * (x * -0.12);
	} else {
		tmp = 1.5334083333333333;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if (x <= -4.0) or not (x <= 2.05):
		tmp = x * (x * -0.12)
	else:
		tmp = 1.5334083333333333
	return tmp
function code(x)
	tmp = 0.0
	if ((x <= -4.0) || !(x <= 2.05))
		tmp = Float64(x * Float64(x * -0.12));
	else
		tmp = 1.5334083333333333;
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if ((x <= -4.0) || ~((x <= 2.05)))
		tmp = x * (x * -0.12);
	else
		tmp = 1.5334083333333333;
	end
	tmp_2 = tmp;
end
code[x_] := If[Or[LessEqual[x, -4.0], N[Not[LessEqual[x, 2.05]], $MachinePrecision]], N[(x * N[(x * -0.12), $MachinePrecision]), $MachinePrecision], 1.5334083333333333]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4 \lor \neg \left(x \leq 2.05\right):\\
\;\;\;\;x \cdot \left(x \cdot -0.12\right)\\

\mathbf{else}:\\
\;\;\;\;1.5334083333333333\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -4 or 2.0499999999999998 < x

    1. Initial program 99.8%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/87.2%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval87.2%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr87.2%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval87.2%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative87.2%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv87.2%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval87.2%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr87.2%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative87.2%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.7%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.7%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.7%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.7%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.3%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.3%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.3%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.3%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
      3. associate-*l*98.3%

        \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]
    9. Simplified98.3%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]

    if -4 < x < 2.0499999999999998

    1. Initial program 100.0%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+100.0%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/100.0%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr100.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*100.0%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*100.0%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative100.0%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified100.0%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 20.2%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around 0 20.2%

      \[\leadsto \color{blue}{1.5334083333333333} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification58.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4 \lor \neg \left(x \leq 2.05\right):\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{else}:\\ \;\;\;\;1.5334083333333333\\ \end{array} \]

Alternative 3: 59.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1.5334083333333333\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -4.0)
   (* x (* x -0.12))
   (if (<= x 2.05) 1.5334083333333333 (* (* x x) -0.12))))
double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x * (x * -0.12);
	} else if (x <= 2.05) {
		tmp = 1.5334083333333333;
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= (-4.0d0)) then
        tmp = x * (x * (-0.12d0))
    else if (x <= 2.05d0) then
        tmp = 1.5334083333333333d0
    else
        tmp = (x * x) * (-0.12d0)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x * (x * -0.12);
	} else if (x <= 2.05) {
		tmp = 1.5334083333333333;
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -4.0:
		tmp = x * (x * -0.12)
	elif x <= 2.05:
		tmp = 1.5334083333333333
	else:
		tmp = (x * x) * -0.12
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -4.0)
		tmp = Float64(x * Float64(x * -0.12));
	elseif (x <= 2.05)
		tmp = 1.5334083333333333;
	else
		tmp = Float64(Float64(x * x) * -0.12);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -4.0)
		tmp = x * (x * -0.12);
	elseif (x <= 2.05)
		tmp = 1.5334083333333333;
	else
		tmp = (x * x) * -0.12;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -4.0], N[(x * N[(x * -0.12), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 2.05], 1.5334083333333333, N[(N[(x * x), $MachinePrecision] * -0.12), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4:\\
\;\;\;\;x \cdot \left(x \cdot -0.12\right)\\

\mathbf{elif}\;x \leq 2.05:\\
\;\;\;\;1.5334083333333333\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot -0.12\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -4

    1. Initial program 99.7%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/84.1%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval84.1%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr84.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative84.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.7%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.7%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.7%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.7%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.0%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.0%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.0%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.0%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
      3. associate-*l*98.0%

        \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]
    9. Simplified98.0%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]

    if -4 < x < 2.0499999999999998

    1. Initial program 100.0%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+100.0%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/100.0%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval100.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr100.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*100.0%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*100.0%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative100.0%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified100.0%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 20.2%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around 0 20.2%

      \[\leadsto \color{blue}{1.5334083333333333} \]

    if 2.0499999999999998 < x

    1. Initial program 99.8%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/90.4%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval90.4%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr90.5%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative90.5%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.8%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.8%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.8%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.8%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.5%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.6%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.6%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
    9. Simplified98.6%

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot -0.12} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification58.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1.5334083333333333\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \]

Alternative 4: 98.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -4.0)
   (* x (* x -0.12))
   (if (<= x 2.05) (- 1.0 (* x 0.253)) (* (* x x) -0.12))))
double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x * (x * -0.12);
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= (-4.0d0)) then
        tmp = x * (x * (-0.12d0))
    else if (x <= 2.05d0) then
        tmp = 1.0d0 - (x * 0.253d0)
    else
        tmp = (x * x) * (-0.12d0)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x * (x * -0.12);
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -4.0:
		tmp = x * (x * -0.12)
	elif x <= 2.05:
		tmp = 1.0 - (x * 0.253)
	else:
		tmp = (x * x) * -0.12
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -4.0)
		tmp = Float64(x * Float64(x * -0.12));
	elseif (x <= 2.05)
		tmp = Float64(1.0 - Float64(x * 0.253));
	else
		tmp = Float64(Float64(x * x) * -0.12);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -4.0)
		tmp = x * (x * -0.12);
	elseif (x <= 2.05)
		tmp = 1.0 - (x * 0.253);
	else
		tmp = (x * x) * -0.12;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -4.0], N[(x * N[(x * -0.12), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 2.05], N[(1.0 - N[(x * 0.253), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * -0.12), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4:\\
\;\;\;\;x \cdot \left(x \cdot -0.12\right)\\

\mathbf{elif}\;x \leq 2.05:\\
\;\;\;\;1 - x \cdot 0.253\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot -0.12\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -4

    1. Initial program 99.7%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/84.1%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval84.1%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr84.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative84.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.7%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.7%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.7%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.7%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.0%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.0%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.0%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.0%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
      3. associate-*l*98.0%

        \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]
    9. Simplified98.0%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]

    if -4 < x < 2.0499999999999998

    1. Initial program 100.0%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Taylor expanded in x around 0 98.8%

      \[\leadsto 1 - \color{blue}{0.253 \cdot x} \]
    3. Step-by-step derivation
      1. *-commutative98.8%

        \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]
    4. Simplified98.8%

      \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]

    if 2.0499999999999998 < x

    1. Initial program 99.8%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/90.4%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval90.4%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr90.5%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative90.5%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.8%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.8%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.8%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.8%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.5%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.6%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.6%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
    9. Simplified98.6%

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot -0.12} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification98.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;x \cdot \left(x \cdot -0.12\right)\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \]

Alternative 5: 98.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;\frac{x}{\frac{-8.333333333333334}{x}}\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -4.0)
   (/ x (/ -8.333333333333334 x))
   (if (<= x 2.05) (- 1.0 (* x 0.253)) (* (* x x) -0.12))))
double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x / (-8.333333333333334 / x);
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= (-4.0d0)) then
        tmp = x / ((-8.333333333333334d0) / x)
    else if (x <= 2.05d0) then
        tmp = 1.0d0 - (x * 0.253d0)
    else
        tmp = (x * x) * (-0.12d0)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = x / (-8.333333333333334 / x);
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -4.0:
		tmp = x / (-8.333333333333334 / x)
	elif x <= 2.05:
		tmp = 1.0 - (x * 0.253)
	else:
		tmp = (x * x) * -0.12
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -4.0)
		tmp = Float64(x / Float64(-8.333333333333334 / x));
	elseif (x <= 2.05)
		tmp = Float64(1.0 - Float64(x * 0.253));
	else
		tmp = Float64(Float64(x * x) * -0.12);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -4.0)
		tmp = x / (-8.333333333333334 / x);
	elseif (x <= 2.05)
		tmp = 1.0 - (x * 0.253);
	else
		tmp = (x * x) * -0.12;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -4.0], N[(x / N[(-8.333333333333334 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 2.05], N[(1.0 - N[(x * 0.253), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * -0.12), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4:\\
\;\;\;\;\frac{x}{\frac{-8.333333333333334}{x}}\\

\mathbf{elif}\;x \leq 2.05:\\
\;\;\;\;1 - x \cdot 0.253\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot -0.12\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -4

    1. Initial program 99.7%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/84.1%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval84.1%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr84.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative84.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.7%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.7%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.7%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.7%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.0%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.0%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.0%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.0%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
      3. associate-*l*98.0%

        \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]
    9. Simplified98.0%

      \[\leadsto \color{blue}{x \cdot \left(x \cdot -0.12\right)} \]
    10. Step-by-step derivation
      1. *-commutative98.0%

        \[\leadsto \color{blue}{\left(x \cdot -0.12\right) \cdot x} \]
      2. metadata-eval98.0%

        \[\leadsto \left(x \cdot \color{blue}{\frac{1}{-8.333333333333334}}\right) \cdot x \]
      3. div-inv98.0%

        \[\leadsto \color{blue}{\frac{x}{-8.333333333333334}} \cdot x \]
      4. associate-/r/98.0%

        \[\leadsto \color{blue}{\frac{x}{\frac{-8.333333333333334}{x}}} \]
    11. Applied egg-rr98.0%

      \[\leadsto \color{blue}{\frac{x}{\frac{-8.333333333333334}{x}}} \]

    if -4 < x < 2.0499999999999998

    1. Initial program 100.0%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Taylor expanded in x around 0 98.8%

      \[\leadsto 1 - \color{blue}{0.253 \cdot x} \]
    3. Step-by-step derivation
      1. *-commutative98.8%

        \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]
    4. Simplified98.8%

      \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]

    if 2.0499999999999998 < x

    1. Initial program 99.8%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/90.4%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval90.4%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr90.5%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative90.5%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.8%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.8%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.8%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.8%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.5%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.6%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.6%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
    9. Simplified98.6%

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot -0.12} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification98.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;\frac{x}{\frac{-8.333333333333334}{x}}\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \]

Alternative 6: 98.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;1.5334083333333333 + \frac{x}{\frac{-8.333333333333334}{x}}\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -4.0)
   (+ 1.5334083333333333 (/ x (/ -8.333333333333334 x)))
   (if (<= x 2.05) (- 1.0 (* x 0.253)) (* (* x x) -0.12))))
double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = 1.5334083333333333 + (x / (-8.333333333333334 / x));
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= (-4.0d0)) then
        tmp = 1.5334083333333333d0 + (x / ((-8.333333333333334d0) / x))
    else if (x <= 2.05d0) then
        tmp = 1.0d0 - (x * 0.253d0)
    else
        tmp = (x * x) * (-0.12d0)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= -4.0) {
		tmp = 1.5334083333333333 + (x / (-8.333333333333334 / x));
	} else if (x <= 2.05) {
		tmp = 1.0 - (x * 0.253);
	} else {
		tmp = (x * x) * -0.12;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -4.0:
		tmp = 1.5334083333333333 + (x / (-8.333333333333334 / x))
	elif x <= 2.05:
		tmp = 1.0 - (x * 0.253)
	else:
		tmp = (x * x) * -0.12
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -4.0)
		tmp = Float64(1.5334083333333333 + Float64(x / Float64(-8.333333333333334 / x)));
	elseif (x <= 2.05)
		tmp = Float64(1.0 - Float64(x * 0.253));
	else
		tmp = Float64(Float64(x * x) * -0.12);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -4.0)
		tmp = 1.5334083333333333 + (x / (-8.333333333333334 / x));
	elseif (x <= 2.05)
		tmp = 1.0 - (x * 0.253);
	else
		tmp = (x * x) * -0.12;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -4.0], N[(1.5334083333333333 + N[(x / N[(-8.333333333333334 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 2.05], N[(1.0 - N[(x * 0.253), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * -0.12), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4:\\
\;\;\;\;1.5334083333333333 + \frac{x}{\frac{-8.333333333333334}{x}}\\

\mathbf{elif}\;x \leq 2.05:\\
\;\;\;\;1 - x \cdot 0.253\\

\mathbf{else}:\\
\;\;\;\;\left(x \cdot x\right) \cdot -0.12\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -4

    1. Initial program 99.7%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/84.1%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval84.1%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval84.0%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr84.0%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative84.0%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.7%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.7%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.7%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.7%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.0%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Step-by-step derivation
      1. div-sub98.0%

        \[\leadsto 1 - \color{blue}{\left(\frac{0.064009}{-0.12} - \frac{x \cdot \left(x \cdot 0.0144\right)}{-0.12}\right)} \]
      2. associate--r-98.0%

        \[\leadsto \color{blue}{\left(1 - \frac{0.064009}{-0.12}\right) + \frac{x \cdot \left(x \cdot 0.0144\right)}{-0.12}} \]
      3. metadata-eval98.0%

        \[\leadsto \left(1 - \color{blue}{-0.5334083333333334}\right) + \frac{x \cdot \left(x \cdot 0.0144\right)}{-0.12} \]
      4. metadata-eval98.0%

        \[\leadsto \color{blue}{1.5334083333333333} + \frac{x \cdot \left(x \cdot 0.0144\right)}{-0.12} \]
      5. associate-*r*97.9%

        \[\leadsto 1.5334083333333333 + \frac{\color{blue}{\left(x \cdot x\right) \cdot 0.0144}}{-0.12} \]
      6. associate-/l*98.0%

        \[\leadsto 1.5334083333333333 + \color{blue}{\frac{x \cdot x}{\frac{-0.12}{0.0144}}} \]
      7. metadata-eval98.0%

        \[\leadsto 1.5334083333333333 + \frac{x \cdot x}{\color{blue}{-8.333333333333334}} \]
    8. Applied egg-rr98.0%

      \[\leadsto \color{blue}{1.5334083333333333 + \frac{x \cdot x}{-8.333333333333334}} \]
    9. Step-by-step derivation
      1. associate-/l*98.1%

        \[\leadsto 1.5334083333333333 + \color{blue}{\frac{x}{\frac{-8.333333333333334}{x}}} \]
    10. Simplified98.1%

      \[\leadsto \color{blue}{1.5334083333333333 + \frac{x}{\frac{-8.333333333333334}{x}}} \]

    if -4 < x < 2.0499999999999998

    1. Initial program 100.0%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Taylor expanded in x around 0 98.8%

      \[\leadsto 1 - \color{blue}{0.253 \cdot x} \]
    3. Step-by-step derivation
      1. *-commutative98.8%

        \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]
    4. Simplified98.8%

      \[\leadsto 1 - \color{blue}{x \cdot 0.253} \]

    if 2.0499999999999998 < x

    1. Initial program 99.8%

      \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
    2. Step-by-step derivation
      1. flip-+99.7%

        \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
      2. associate-*r/90.4%

        \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
      3. metadata-eval90.4%

        \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
      4. swap-sqr90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
      5. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
      6. *-commutative90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
      7. cancel-sign-sub-inv90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
      8. metadata-eval90.5%

        \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
    3. Applied egg-rr90.5%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
    4. Step-by-step derivation
      1. *-commutative90.5%

        \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
      2. associate-/l*99.8%

        \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
      3. associate-*l*99.8%

        \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
      4. *-commutative99.8%

        \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
    5. Simplified99.8%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
    6. Taylor expanded in x around inf 98.5%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
    7. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{-0.12 \cdot {x}^{2}} \]
    8. Step-by-step derivation
      1. *-commutative98.6%

        \[\leadsto \color{blue}{{x}^{2} \cdot -0.12} \]
      2. unpow298.6%

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot -0.12 \]
    9. Simplified98.6%

      \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot -0.12} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification98.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4:\\ \;\;\;\;1.5334083333333333 + \frac{x}{\frac{-8.333333333333334}{x}}\\ \mathbf{elif}\;x \leq 2.05:\\ \;\;\;\;1 - x \cdot 0.253\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot x\right) \cdot -0.12\\ \end{array} \]

Alternative 7: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ 1 - x \cdot \left(0.253 + x \cdot 0.12\right) \end{array} \]
(FPCore (x) :precision binary64 (- 1.0 (* x (+ 0.253 (* x 0.12)))))
double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - (x * (0.253d0 + (x * 0.12d0)))
end function
public static double code(double x) {
	return 1.0 - (x * (0.253 + (x * 0.12)));
}
def code(x):
	return 1.0 - (x * (0.253 + (x * 0.12)))
function code(x)
	return Float64(1.0 - Float64(x * Float64(0.253 + Float64(x * 0.12))))
end
function tmp = code(x)
	tmp = 1.0 - (x * (0.253 + (x * 0.12)));
end
code[x_] := N[(1.0 - N[(x * N[(0.253 + N[(x * 0.12), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - x \cdot \left(0.253 + x \cdot 0.12\right)
\end{array}
Derivation
  1. Initial program 99.9%

    \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
  2. Final simplification99.9%

    \[\leadsto 1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]

Alternative 8: 97.6% accurate, 1.3× speedup?

\[\begin{array}{l} \\ 1 - 0.12 \cdot \left(x \cdot x\right) \end{array} \]
(FPCore (x) :precision binary64 (- 1.0 (* 0.12 (* x x))))
double code(double x) {
	return 1.0 - (0.12 * (x * x));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 - (0.12d0 * (x * x))
end function
public static double code(double x) {
	return 1.0 - (0.12 * (x * x));
}
def code(x):
	return 1.0 - (0.12 * (x * x))
function code(x)
	return Float64(1.0 - Float64(0.12 * Float64(x * x)))
end
function tmp = code(x)
	tmp = 1.0 - (0.12 * (x * x));
end
code[x_] := N[(1.0 - N[(0.12 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - 0.12 \cdot \left(x \cdot x\right)
\end{array}
Derivation
  1. Initial program 99.9%

    \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
  2. Taylor expanded in x around inf 98.1%

    \[\leadsto 1 - \color{blue}{0.12 \cdot {x}^{2}} \]
  3. Step-by-step derivation
    1. unpow298.1%

      \[\leadsto 1 - 0.12 \cdot \color{blue}{\left(x \cdot x\right)} \]
  4. Simplified98.1%

    \[\leadsto 1 - \color{blue}{0.12 \cdot \left(x \cdot x\right)} \]
  5. Final simplification98.1%

    \[\leadsto 1 - 0.12 \cdot \left(x \cdot x\right) \]

Alternative 9: 10.4% accurate, 9.0× speedup?

\[\begin{array}{l} \\ 1.5334083333333333 \end{array} \]
(FPCore (x) :precision binary64 1.5334083333333333)
double code(double x) {
	return 1.5334083333333333;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.5334083333333333d0
end function
public static double code(double x) {
	return 1.5334083333333333;
}
def code(x):
	return 1.5334083333333333
function code(x)
	return 1.5334083333333333
end
function tmp = code(x)
	tmp = 1.5334083333333333;
end
code[x_] := 1.5334083333333333
\begin{array}{l}

\\
1.5334083333333333
\end{array}
Derivation
  1. Initial program 99.9%

    \[1 - x \cdot \left(0.253 + x \cdot 0.12\right) \]
  2. Step-by-step derivation
    1. flip-+99.9%

      \[\leadsto 1 - x \cdot \color{blue}{\frac{0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)}{0.253 - x \cdot 0.12}} \]
    2. associate-*r/93.8%

      \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.253 \cdot 0.253 - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12}} \]
    3. metadata-eval93.8%

      \[\leadsto 1 - \frac{x \cdot \left(\color{blue}{0.064009} - \left(x \cdot 0.12\right) \cdot \left(x \cdot 0.12\right)\right)}{0.253 - x \cdot 0.12} \]
    4. swap-sqr93.8%

      \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \color{blue}{\left(x \cdot x\right) \cdot \left(0.12 \cdot 0.12\right)}\right)}{0.253 - x \cdot 0.12} \]
    5. metadata-eval93.8%

      \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot \color{blue}{0.0144}\right)}{0.253 - x \cdot 0.12} \]
    6. *-commutative93.8%

      \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 - \color{blue}{0.12 \cdot x}} \]
    7. cancel-sign-sub-inv93.8%

      \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{\color{blue}{0.253 + \left(-0.12\right) \cdot x}} \]
    8. metadata-eval93.8%

      \[\leadsto 1 - \frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + \color{blue}{-0.12} \cdot x} \]
  3. Applied egg-rr93.8%

    \[\leadsto 1 - \color{blue}{\frac{x \cdot \left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right)}{0.253 + -0.12 \cdot x}} \]
  4. Step-by-step derivation
    1. *-commutative93.8%

      \[\leadsto 1 - \frac{\color{blue}{\left(0.064009 - \left(x \cdot x\right) \cdot 0.0144\right) \cdot x}}{0.253 + -0.12 \cdot x} \]
    2. associate-/l*99.9%

      \[\leadsto 1 - \color{blue}{\frac{0.064009 - \left(x \cdot x\right) \cdot 0.0144}{\frac{0.253 + -0.12 \cdot x}{x}}} \]
    3. associate-*l*99.9%

      \[\leadsto 1 - \frac{0.064009 - \color{blue}{x \cdot \left(x \cdot 0.0144\right)}}{\frac{0.253 + -0.12 \cdot x}{x}} \]
    4. *-commutative99.9%

      \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + \color{blue}{x \cdot -0.12}}{x}} \]
  5. Simplified99.9%

    \[\leadsto 1 - \color{blue}{\frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\frac{0.253 + x \cdot -0.12}{x}}} \]
  6. Taylor expanded in x around inf 58.0%

    \[\leadsto 1 - \frac{0.064009 - x \cdot \left(x \cdot 0.0144\right)}{\color{blue}{-0.12}} \]
  7. Taylor expanded in x around 0 10.8%

    \[\leadsto \color{blue}{1.5334083333333333} \]
  8. Final simplification10.8%

    \[\leadsto 1.5334083333333333 \]

Reproduce

?
herbie shell --seed 2023238 
(FPCore (x)
  :name "Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, A"
  :precision binary64
  (- 1.0 (* x (+ 0.253 (* x 0.12)))))