Octave 3.8, jcobi/1

Percentage Accurate: 74.4% → 99.6%
Time: 7.1s
Alternatives: 9
Speedup: 0.9×

Specification

?
\[\alpha > -1 \land \beta > -1\]
\[\begin{array}{l} \\ \frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))
double code(double alpha, double beta) {
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    code = (((beta - alpha) / ((alpha + beta) + 2.0d0)) + 1.0d0) / 2.0d0
end function
public static double code(double alpha, double beta) {
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
def code(alpha, beta):
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0
function code(alpha, beta)
	return Float64(Float64(Float64(Float64(beta - alpha) / Float64(Float64(alpha + beta) + 2.0)) + 1.0) / 2.0)
end
function tmp = code(alpha, beta)
	tmp = (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
end
code[alpha_, beta_] := N[(N[(N[(N[(beta - alpha), $MachinePrecision] / N[(N[(alpha + beta), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}
\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: 74.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))
double code(double alpha, double beta) {
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    code = (((beta - alpha) / ((alpha + beta) + 2.0d0)) + 1.0d0) / 2.0d0
end function
public static double code(double alpha, double beta) {
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
}
def code(alpha, beta):
	return (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0
function code(alpha, beta)
	return Float64(Float64(Float64(Float64(beta - alpha) / Float64(Float64(alpha + beta) + 2.0)) + 1.0) / 2.0)
end
function tmp = code(alpha, beta)
	tmp = (((beta - alpha) / ((alpha + beta) + 2.0)) + 1.0) / 2.0;
end
code[alpha_, beta_] := N[(N[(N[(N[(beta - alpha), $MachinePrecision] / N[(N[(alpha + beta), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}
\end{array}

Alternative 1: 99.6% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{\left(\beta + 1\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{\beta + 2}{\alpha}\right)}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{t\_0 + 1}{2}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ (+ beta alpha) 2.0))))
   (if (<= t_0 -0.5)
     (/
      (+
       (+ beta 1.0)
       (* 0.5 (* (- (- -2.0 beta) beta) (/ (+ beta 2.0) alpha))))
      alpha)
     (/ (+ t_0 1.0) 2.0))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	double tmp;
	if (t_0 <= -0.5) {
		tmp = ((beta + 1.0) + (0.5 * (((-2.0 - beta) - beta) * ((beta + 2.0) / alpha)))) / alpha;
	} else {
		tmp = (t_0 + 1.0) / 2.0;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (beta - alpha) / ((beta + alpha) + 2.0d0)
    if (t_0 <= (-0.5d0)) then
        tmp = ((beta + 1.0d0) + (0.5d0 * ((((-2.0d0) - beta) - beta) * ((beta + 2.0d0) / alpha)))) / alpha
    else
        tmp = (t_0 + 1.0d0) / 2.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	double tmp;
	if (t_0 <= -0.5) {
		tmp = ((beta + 1.0) + (0.5 * (((-2.0 - beta) - beta) * ((beta + 2.0) / alpha)))) / alpha;
	} else {
		tmp = (t_0 + 1.0) / 2.0;
	}
	return tmp;
}
def code(alpha, beta):
	t_0 = (beta - alpha) / ((beta + alpha) + 2.0)
	tmp = 0
	if t_0 <= -0.5:
		tmp = ((beta + 1.0) + (0.5 * (((-2.0 - beta) - beta) * ((beta + 2.0) / alpha)))) / alpha
	else:
		tmp = (t_0 + 1.0) / 2.0
	return tmp
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(Float64(beta + alpha) + 2.0))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(Float64(Float64(beta + 1.0) + Float64(0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) * Float64(Float64(beta + 2.0) / alpha)))) / alpha);
	else
		tmp = Float64(Float64(t_0 + 1.0) / 2.0);
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	tmp = 0.0;
	if (t_0 <= -0.5)
		tmp = ((beta + 1.0) + (0.5 * (((-2.0 - beta) - beta) * ((beta + 2.0) / alpha)))) / alpha;
	else
		tmp = (t_0 + 1.0) / 2.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(N[(beta + alpha), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(N[(N[(beta + 1.0), $MachinePrecision] + N[(0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] * N[(N[(beta + 2.0), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(t$95$0 + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2}\\
\mathbf{if}\;t\_0 \leq -0.5:\\
\;\;\;\;\frac{\left(\beta + 1\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{\beta + 2}{\alpha}\right)}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;\frac{t\_0 + 1}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.8%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around inf

      \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}}{\alpha}} \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}\right), \color{blue}{\alpha}\right) \]
    5. Simplified99.9%

      \[\leadsto \color{blue}{\frac{\left(1 + \beta\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{2 + \beta}{\alpha}\right)}{\alpha}} \]

    if -0.5 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64)))

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.5:\\ \;\;\;\;\frac{\left(\beta + 1\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{\beta + 2}{\alpha}\right)}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{t\_0 + 1}{2}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ (+ beta alpha) 2.0))))
   (if (<= t_0 -0.5)
     (/ (+ (+ beta 1.0) (/ -2.0 alpha)) alpha)
     (/ (+ t_0 1.0) 2.0))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	double tmp;
	if (t_0 <= -0.5) {
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	} else {
		tmp = (t_0 + 1.0) / 2.0;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (beta - alpha) / ((beta + alpha) + 2.0d0)
    if (t_0 <= (-0.5d0)) then
        tmp = ((beta + 1.0d0) + ((-2.0d0) / alpha)) / alpha
    else
        tmp = (t_0 + 1.0d0) / 2.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	double tmp;
	if (t_0 <= -0.5) {
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	} else {
		tmp = (t_0 + 1.0) / 2.0;
	}
	return tmp;
}
def code(alpha, beta):
	t_0 = (beta - alpha) / ((beta + alpha) + 2.0)
	tmp = 0
	if t_0 <= -0.5:
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha
	else:
		tmp = (t_0 + 1.0) / 2.0
	return tmp
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(Float64(beta + alpha) + 2.0))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(Float64(Float64(beta + 1.0) + Float64(-2.0 / alpha)) / alpha);
	else
		tmp = Float64(Float64(t_0 + 1.0) / 2.0);
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	t_0 = (beta - alpha) / ((beta + alpha) + 2.0);
	tmp = 0.0;
	if (t_0 <= -0.5)
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	else
		tmp = (t_0 + 1.0) / 2.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(N[(beta + alpha), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(N[(N[(beta + 1.0), $MachinePrecision] + N[(-2.0 / alpha), $MachinePrecision]), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(t$95$0 + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2}\\
\mathbf{if}\;t\_0 \leq -0.5:\\
\;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;\frac{t\_0 + 1}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.8%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around inf

      \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}}{\alpha}} \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}\right), \color{blue}{\alpha}\right) \]
    5. Simplified99.9%

      \[\leadsto \color{blue}{\frac{\left(1 + \beta\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{2 + \beta}{\alpha}\right)}{\alpha}} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \color{blue}{\left(\frac{-2}{\alpha}\right)}\right), \alpha\right) \]
    7. Step-by-step derivation
      1. /-lowering-/.f6499.9%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \mathsf{/.f64}\left(-2, \alpha\right)\right), \alpha\right) \]
    8. Simplified99.9%

      \[\leadsto \frac{\left(1 + \beta\right) + \color{blue}{\frac{-2}{\alpha}}}{\alpha} \]

    if -0.5 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64)))

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.5:\\ \;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 70.7% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 1.1 \cdot 10^{-25}:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{elif}\;\beta \leq 465000000:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= beta 1.1e-25)
   (+ 0.5 (* beta 0.25))
   (if (<= beta 465000000.0) (/ (+ beta 1.0) alpha) (+ 1.0 (/ -1.0 beta)))))
double code(double alpha, double beta) {
	double tmp;
	if (beta <= 1.1e-25) {
		tmp = 0.5 + (beta * 0.25);
	} else if (beta <= 465000000.0) {
		tmp = (beta + 1.0) / alpha;
	} else {
		tmp = 1.0 + (-1.0 / beta);
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (beta <= 1.1d-25) then
        tmp = 0.5d0 + (beta * 0.25d0)
    else if (beta <= 465000000.0d0) then
        tmp = (beta + 1.0d0) / alpha
    else
        tmp = 1.0d0 + ((-1.0d0) / beta)
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (beta <= 1.1e-25) {
		tmp = 0.5 + (beta * 0.25);
	} else if (beta <= 465000000.0) {
		tmp = (beta + 1.0) / alpha;
	} else {
		tmp = 1.0 + (-1.0 / beta);
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if beta <= 1.1e-25:
		tmp = 0.5 + (beta * 0.25)
	elif beta <= 465000000.0:
		tmp = (beta + 1.0) / alpha
	else:
		tmp = 1.0 + (-1.0 / beta)
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (beta <= 1.1e-25)
		tmp = Float64(0.5 + Float64(beta * 0.25));
	elseif (beta <= 465000000.0)
		tmp = Float64(Float64(beta + 1.0) / alpha);
	else
		tmp = Float64(1.0 + Float64(-1.0 / beta));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (beta <= 1.1e-25)
		tmp = 0.5 + (beta * 0.25);
	elseif (beta <= 465000000.0)
		tmp = (beta + 1.0) / alpha;
	else
		tmp = 1.0 + (-1.0 / beta);
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[beta, 1.1e-25], N[(0.5 + N[(beta * 0.25), $MachinePrecision]), $MachinePrecision], If[LessEqual[beta, 465000000.0], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], N[(1.0 + N[(-1.0 / beta), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\beta \leq 1.1 \cdot 10^{-25}:\\
\;\;\;\;0.5 + \beta \cdot 0.25\\

\mathbf{elif}\;\beta \leq 465000000:\\
\;\;\;\;\frac{\beta + 1}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;1 + \frac{-1}{\beta}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if beta < 1.1000000000000001e-25

    1. Initial program 76.5%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
      2. +-lowering-+.f6473.6%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
    5. Simplified73.6%

      \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \color{blue}{\frac{1}{2} + \frac{1}{4} \cdot \beta} \]
    7. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{\left(\frac{1}{4} \cdot \beta\right)}\right) \]
      2. *-lowering-*.f6473.5%

        \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{1}{4}, \color{blue}{\beta}\right)\right) \]
    8. Simplified73.5%

      \[\leadsto \color{blue}{0.5 + 0.25 \cdot \beta} \]

    if 1.1000000000000001e-25 < beta < 4.65e8

    1. Initial program 13.1%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{2 + 2 \cdot \beta}{\alpha}} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right)}{\color{blue}{\alpha}} \]
      2. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right)\right), \color{blue}{\alpha}\right) \]
      3. distribute-lft-inN/A

        \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot 2 + \frac{1}{2} \cdot \left(2 \cdot \beta\right)\right), \alpha\right) \]
      4. metadata-evalN/A

        \[\leadsto \mathsf{/.f64}\left(\left(1 + \frac{1}{2} \cdot \left(2 \cdot \beta\right)\right), \alpha\right) \]
      5. associate-*r*N/A

        \[\leadsto \mathsf{/.f64}\left(\left(1 + \left(\frac{1}{2} \cdot 2\right) \cdot \beta\right), \alpha\right) \]
      6. metadata-evalN/A

        \[\leadsto \mathsf{/.f64}\left(\left(1 + 1 \cdot \beta\right), \alpha\right) \]
      7. *-lft-identityN/A

        \[\leadsto \mathsf{/.f64}\left(\left(1 + \beta\right), \alpha\right) \]
      8. +-lowering-+.f6490.9%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \alpha\right) \]
    5. Simplified90.9%

      \[\leadsto \color{blue}{\frac{1 + \beta}{\alpha}} \]

    if 4.65e8 < beta

    1. Initial program 91.2%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
      2. +-lowering-+.f6491.2%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
    5. Simplified91.2%

      \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
    6. Taylor expanded in beta around inf

      \[\leadsto \color{blue}{1 - \frac{1}{\beta}} \]
    7. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto 1 + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{\beta}\right)\right)} \]
      2. +-lowering-+.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \color{blue}{\left(\mathsf{neg}\left(\frac{1}{\beta}\right)\right)}\right) \]
      3. distribute-neg-fracN/A

        \[\leadsto \mathsf{+.f64}\left(1, \left(\frac{\mathsf{neg}\left(1\right)}{\color{blue}{\beta}}\right)\right) \]
      4. metadata-evalN/A

        \[\leadsto \mathsf{+.f64}\left(1, \left(\frac{-1}{\beta}\right)\right) \]
      5. /-lowering-/.f6491.2%

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{/.f64}\left(-1, \color{blue}{\beta}\right)\right) \]
    8. Simplified91.2%

      \[\leadsto \color{blue}{1 + \frac{-1}{\beta}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification80.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\beta \leq 1.1 \cdot 10^{-25}:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{elif}\;\beta \leq 465000000:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 93.2% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\alpha \leq 165000:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= alpha 165000.0)
   (/ (+ 1.0 (/ beta (+ beta 2.0))) 2.0)
   (/ (+ (+ beta 1.0) (/ -2.0 alpha)) alpha)))
double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 165000.0) {
		tmp = (1.0 + (beta / (beta + 2.0))) / 2.0;
	} else {
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (alpha <= 165000.0d0) then
        tmp = (1.0d0 + (beta / (beta + 2.0d0))) / 2.0d0
    else
        tmp = ((beta + 1.0d0) + ((-2.0d0) / alpha)) / alpha
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 165000.0) {
		tmp = (1.0 + (beta / (beta + 2.0))) / 2.0;
	} else {
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if alpha <= 165000.0:
		tmp = (1.0 + (beta / (beta + 2.0))) / 2.0
	else:
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (alpha <= 165000.0)
		tmp = Float64(Float64(1.0 + Float64(beta / Float64(beta + 2.0))) / 2.0);
	else
		tmp = Float64(Float64(Float64(beta + 1.0) + Float64(-2.0 / alpha)) / alpha);
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (alpha <= 165000.0)
		tmp = (1.0 + (beta / (beta + 2.0))) / 2.0;
	else
		tmp = ((beta + 1.0) + (-2.0 / alpha)) / alpha;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[alpha, 165000.0], N[(N[(1.0 + N[(beta / N[(beta + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(N[(beta + 1.0), $MachinePrecision] + N[(-2.0 / alpha), $MachinePrecision]), $MachinePrecision] / alpha), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\alpha \leq 165000:\\
\;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\

\mathbf{else}:\\
\;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if alpha < 165000

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
      2. +-lowering-+.f6498.6%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
    5. Simplified98.6%

      \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]

    if 165000 < alpha

    1. Initial program 26.1%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around inf

      \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}}{\alpha}} \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right) + \frac{1}{2} \cdot \frac{-1 \cdot {\left(2 + \beta\right)}^{2} - \beta \cdot \left(2 + \beta\right)}{\alpha}\right), \color{blue}{\alpha}\right) \]
    5. Simplified81.2%

      \[\leadsto \color{blue}{\frac{\left(1 + \beta\right) + 0.5 \cdot \left(\left(\left(-2 - \beta\right) - \beta\right) \cdot \frac{2 + \beta}{\alpha}\right)}{\alpha}} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \color{blue}{\left(\frac{-2}{\alpha}\right)}\right), \alpha\right) \]
    7. Step-by-step derivation
      1. /-lowering-/.f6482.1%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \mathsf{/.f64}\left(-2, \alpha\right)\right), \alpha\right) \]
    8. Simplified82.1%

      \[\leadsto \frac{\left(1 + \beta\right) + \color{blue}{\frac{-2}{\alpha}}}{\alpha} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \leq 165000:\\ \;\;\;\;\frac{1 + \frac{\beta}{\beta + 2}}{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(\beta + 1\right) + \frac{-2}{\alpha}}{\alpha}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 70.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 1.05 \cdot 10^{-25}:\\ \;\;\;\;0.5\\ \mathbf{elif}\;\beta \leq 465000000:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= beta 1.05e-25) 0.5 (if (<= beta 465000000.0) (/ 1.0 alpha) 1.0)))
double code(double alpha, double beta) {
	double tmp;
	if (beta <= 1.05e-25) {
		tmp = 0.5;
	} else if (beta <= 465000000.0) {
		tmp = 1.0 / alpha;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (beta <= 1.05d-25) then
        tmp = 0.5d0
    else if (beta <= 465000000.0d0) then
        tmp = 1.0d0 / alpha
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (beta <= 1.05e-25) {
		tmp = 0.5;
	} else if (beta <= 465000000.0) {
		tmp = 1.0 / alpha;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if beta <= 1.05e-25:
		tmp = 0.5
	elif beta <= 465000000.0:
		tmp = 1.0 / alpha
	else:
		tmp = 1.0
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (beta <= 1.05e-25)
		tmp = 0.5;
	elseif (beta <= 465000000.0)
		tmp = Float64(1.0 / alpha);
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (beta <= 1.05e-25)
		tmp = 0.5;
	elseif (beta <= 465000000.0)
		tmp = 1.0 / alpha;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[beta, 1.05e-25], 0.5, If[LessEqual[beta, 465000000.0], N[(1.0 / alpha), $MachinePrecision], 1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\beta \leq 1.05 \cdot 10^{-25}:\\
\;\;\;\;0.5\\

\mathbf{elif}\;\beta \leq 465000000:\\
\;\;\;\;\frac{1}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if beta < 1.05000000000000001e-25

    1. Initial program 76.5%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in alpha around 0

      \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
    4. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
      2. +-lowering-+.f6473.6%

        \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
    5. Simplified73.6%

      \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \color{blue}{\frac{1}{2}} \]
    7. Step-by-step derivation
      1. Simplified72.9%

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

      if 1.05000000000000001e-25 < beta < 4.65e8

      1. Initial program 13.1%

        \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in alpha around inf

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{2 + 2 \cdot \beta}{\alpha}} \]
      4. Step-by-step derivation
        1. associate-*r/N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right)}{\color{blue}{\alpha}} \]
        2. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot \left(2 + 2 \cdot \beta\right)\right), \color{blue}{\alpha}\right) \]
        3. distribute-lft-inN/A

          \[\leadsto \mathsf{/.f64}\left(\left(\frac{1}{2} \cdot 2 + \frac{1}{2} \cdot \left(2 \cdot \beta\right)\right), \alpha\right) \]
        4. metadata-evalN/A

          \[\leadsto \mathsf{/.f64}\left(\left(1 + \frac{1}{2} \cdot \left(2 \cdot \beta\right)\right), \alpha\right) \]
        5. associate-*r*N/A

          \[\leadsto \mathsf{/.f64}\left(\left(1 + \left(\frac{1}{2} \cdot 2\right) \cdot \beta\right), \alpha\right) \]
        6. metadata-evalN/A

          \[\leadsto \mathsf{/.f64}\left(\left(1 + 1 \cdot \beta\right), \alpha\right) \]
        7. *-lft-identityN/A

          \[\leadsto \mathsf{/.f64}\left(\left(1 + \beta\right), \alpha\right) \]
        8. +-lowering-+.f6490.9%

          \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(1, \beta\right), \alpha\right) \]
      5. Simplified90.9%

        \[\leadsto \color{blue}{\frac{1 + \beta}{\alpha}} \]
      6. Taylor expanded in beta around 0

        \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
      7. Step-by-step derivation
        1. /-lowering-/.f6450.2%

          \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\alpha}\right) \]
      8. Simplified50.2%

        \[\leadsto \color{blue}{\frac{1}{\alpha}} \]

      if 4.65e8 < beta

      1. Initial program 91.2%

        \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in beta around inf

        \[\leadsto \color{blue}{1} \]
      4. Step-by-step derivation
        1. Simplified90.9%

          \[\leadsto \color{blue}{1} \]
      5. Recombined 3 regimes into one program.
      6. Add Preprocessing

      Alternative 6: 71.6% accurate, 1.3× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 2:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \end{array} \]
      (FPCore (alpha beta)
       :precision binary64
       (if (<= beta 2.0) (+ 0.5 (* beta 0.25)) (+ 1.0 (/ -1.0 beta))))
      double code(double alpha, double beta) {
      	double tmp;
      	if (beta <= 2.0) {
      		tmp = 0.5 + (beta * 0.25);
      	} else {
      		tmp = 1.0 + (-1.0 / beta);
      	}
      	return tmp;
      }
      
      real(8) function code(alpha, beta)
          real(8), intent (in) :: alpha
          real(8), intent (in) :: beta
          real(8) :: tmp
          if (beta <= 2.0d0) then
              tmp = 0.5d0 + (beta * 0.25d0)
          else
              tmp = 1.0d0 + ((-1.0d0) / beta)
          end if
          code = tmp
      end function
      
      public static double code(double alpha, double beta) {
      	double tmp;
      	if (beta <= 2.0) {
      		tmp = 0.5 + (beta * 0.25);
      	} else {
      		tmp = 1.0 + (-1.0 / beta);
      	}
      	return tmp;
      }
      
      def code(alpha, beta):
      	tmp = 0
      	if beta <= 2.0:
      		tmp = 0.5 + (beta * 0.25)
      	else:
      		tmp = 1.0 + (-1.0 / beta)
      	return tmp
      
      function code(alpha, beta)
      	tmp = 0.0
      	if (beta <= 2.0)
      		tmp = Float64(0.5 + Float64(beta * 0.25));
      	else
      		tmp = Float64(1.0 + Float64(-1.0 / beta));
      	end
      	return tmp
      end
      
      function tmp_2 = code(alpha, beta)
      	tmp = 0.0;
      	if (beta <= 2.0)
      		tmp = 0.5 + (beta * 0.25);
      	else
      		tmp = 1.0 + (-1.0 / beta);
      	end
      	tmp_2 = tmp;
      end
      
      code[alpha_, beta_] := If[LessEqual[beta, 2.0], N[(0.5 + N[(beta * 0.25), $MachinePrecision]), $MachinePrecision], N[(1.0 + N[(-1.0 / beta), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\beta \leq 2:\\
      \;\;\;\;0.5 + \beta \cdot 0.25\\
      
      \mathbf{else}:\\
      \;\;\;\;1 + \frac{-1}{\beta}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if beta < 2

        1. Initial program 73.6%

          \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
        2. Add Preprocessing
        3. Taylor expanded in alpha around 0

          \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
        4. Step-by-step derivation
          1. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
          2. +-lowering-+.f6470.9%

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
        5. Simplified70.9%

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        6. Taylor expanded in beta around 0

          \[\leadsto \color{blue}{\frac{1}{2} + \frac{1}{4} \cdot \beta} \]
        7. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{\left(\frac{1}{4} \cdot \beta\right)}\right) \]
          2. *-lowering-*.f6470.9%

            \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{1}{4}, \color{blue}{\beta}\right)\right) \]
        8. Simplified70.9%

          \[\leadsto \color{blue}{0.5 + 0.25 \cdot \beta} \]

        if 2 < beta

        1. Initial program 88.3%

          \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
        2. Add Preprocessing
        3. Taylor expanded in alpha around 0

          \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
        4. Step-by-step derivation
          1. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
          2. +-lowering-+.f6488.3%

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
        5. Simplified88.3%

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        6. Taylor expanded in beta around inf

          \[\leadsto \color{blue}{1 - \frac{1}{\beta}} \]
        7. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto 1 + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{\beta}\right)\right)} \]
          2. +-lowering-+.f64N/A

            \[\leadsto \mathsf{+.f64}\left(1, \color{blue}{\left(\mathsf{neg}\left(\frac{1}{\beta}\right)\right)}\right) \]
          3. distribute-neg-fracN/A

            \[\leadsto \mathsf{+.f64}\left(1, \left(\frac{\mathsf{neg}\left(1\right)}{\color{blue}{\beta}}\right)\right) \]
          4. metadata-evalN/A

            \[\leadsto \mathsf{+.f64}\left(1, \left(\frac{-1}{\beta}\right)\right) \]
          5. /-lowering-/.f6488.3%

            \[\leadsto \mathsf{+.f64}\left(1, \mathsf{/.f64}\left(-1, \color{blue}{\beta}\right)\right) \]
        8. Simplified88.3%

          \[\leadsto \color{blue}{1 + \frac{-1}{\beta}} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification76.8%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\beta \leq 2:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \]
      5. Add Preprocessing

      Alternative 7: 71.4% accurate, 1.3× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 2:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
      (FPCore (alpha beta)
       :precision binary64
       (if (<= beta 2.0) (+ 0.5 (* beta 0.25)) 1.0))
      double code(double alpha, double beta) {
      	double tmp;
      	if (beta <= 2.0) {
      		tmp = 0.5 + (beta * 0.25);
      	} else {
      		tmp = 1.0;
      	}
      	return tmp;
      }
      
      real(8) function code(alpha, beta)
          real(8), intent (in) :: alpha
          real(8), intent (in) :: beta
          real(8) :: tmp
          if (beta <= 2.0d0) then
              tmp = 0.5d0 + (beta * 0.25d0)
          else
              tmp = 1.0d0
          end if
          code = tmp
      end function
      
      public static double code(double alpha, double beta) {
      	double tmp;
      	if (beta <= 2.0) {
      		tmp = 0.5 + (beta * 0.25);
      	} else {
      		tmp = 1.0;
      	}
      	return tmp;
      }
      
      def code(alpha, beta):
      	tmp = 0
      	if beta <= 2.0:
      		tmp = 0.5 + (beta * 0.25)
      	else:
      		tmp = 1.0
      	return tmp
      
      function code(alpha, beta)
      	tmp = 0.0
      	if (beta <= 2.0)
      		tmp = Float64(0.5 + Float64(beta * 0.25));
      	else
      		tmp = 1.0;
      	end
      	return tmp
      end
      
      function tmp_2 = code(alpha, beta)
      	tmp = 0.0;
      	if (beta <= 2.0)
      		tmp = 0.5 + (beta * 0.25);
      	else
      		tmp = 1.0;
      	end
      	tmp_2 = tmp;
      end
      
      code[alpha_, beta_] := If[LessEqual[beta, 2.0], N[(0.5 + N[(beta * 0.25), $MachinePrecision]), $MachinePrecision], 1.0]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\beta \leq 2:\\
      \;\;\;\;0.5 + \beta \cdot 0.25\\
      
      \mathbf{else}:\\
      \;\;\;\;1\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if beta < 2

        1. Initial program 73.6%

          \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
        2. Add Preprocessing
        3. Taylor expanded in alpha around 0

          \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
        4. Step-by-step derivation
          1. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
          2. +-lowering-+.f6470.9%

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
        5. Simplified70.9%

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        6. Taylor expanded in beta around 0

          \[\leadsto \color{blue}{\frac{1}{2} + \frac{1}{4} \cdot \beta} \]
        7. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{\left(\frac{1}{4} \cdot \beta\right)}\right) \]
          2. *-lowering-*.f6470.9%

            \[\leadsto \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\frac{1}{4}, \color{blue}{\beta}\right)\right) \]
        8. Simplified70.9%

          \[\leadsto \color{blue}{0.5 + 0.25 \cdot \beta} \]

        if 2 < beta

        1. Initial program 88.3%

          \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
        2. Add Preprocessing
        3. Taylor expanded in beta around inf

          \[\leadsto \color{blue}{1} \]
        4. Step-by-step derivation
          1. Simplified88.0%

            \[\leadsto \color{blue}{1} \]
        5. Recombined 2 regimes into one program.
        6. Final simplification76.7%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\beta \leq 2:\\ \;\;\;\;0.5 + \beta \cdot 0.25\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
        7. Add Preprocessing

        Alternative 8: 70.8% accurate, 2.2× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 465000000:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
        (FPCore (alpha beta) :precision binary64 (if (<= beta 465000000.0) 0.5 1.0))
        double code(double alpha, double beta) {
        	double tmp;
        	if (beta <= 465000000.0) {
        		tmp = 0.5;
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        real(8) function code(alpha, beta)
            real(8), intent (in) :: alpha
            real(8), intent (in) :: beta
            real(8) :: tmp
            if (beta <= 465000000.0d0) then
                tmp = 0.5d0
            else
                tmp = 1.0d0
            end if
            code = tmp
        end function
        
        public static double code(double alpha, double beta) {
        	double tmp;
        	if (beta <= 465000000.0) {
        		tmp = 0.5;
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        def code(alpha, beta):
        	tmp = 0
        	if beta <= 465000000.0:
        		tmp = 0.5
        	else:
        		tmp = 1.0
        	return tmp
        
        function code(alpha, beta)
        	tmp = 0.0
        	if (beta <= 465000000.0)
        		tmp = 0.5;
        	else
        		tmp = 1.0;
        	end
        	return tmp
        end
        
        function tmp_2 = code(alpha, beta)
        	tmp = 0.0;
        	if (beta <= 465000000.0)
        		tmp = 0.5;
        	else
        		tmp = 1.0;
        	end
        	tmp_2 = tmp;
        end
        
        code[alpha_, beta_] := If[LessEqual[beta, 465000000.0], 0.5, 1.0]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\beta \leq 465000000:\\
        \;\;\;\;0.5\\
        
        \mathbf{else}:\\
        \;\;\;\;1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if beta < 4.65e8

          1. Initial program 72.4%

            \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
          2. Add Preprocessing
          3. Taylor expanded in alpha around 0

            \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
          4. Step-by-step derivation
            1. /-lowering-/.f64N/A

              \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
            2. +-lowering-+.f6469.8%

              \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
          5. Simplified69.8%

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
          6. Taylor expanded in beta around 0

            \[\leadsto \color{blue}{\frac{1}{2}} \]
          7. Step-by-step derivation
            1. Simplified69.0%

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

            if 4.65e8 < beta

            1. Initial program 91.2%

              \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
            2. Add Preprocessing
            3. Taylor expanded in beta around inf

              \[\leadsto \color{blue}{1} \]
            4. Step-by-step derivation
              1. Simplified90.9%

                \[\leadsto \color{blue}{1} \]
            5. Recombined 2 regimes into one program.
            6. Add Preprocessing

            Alternative 9: 48.9% accurate, 13.0× speedup?

            \[\begin{array}{l} \\ 0.5 \end{array} \]
            (FPCore (alpha beta) :precision binary64 0.5)
            double code(double alpha, double beta) {
            	return 0.5;
            }
            
            real(8) function code(alpha, beta)
                real(8), intent (in) :: alpha
                real(8), intent (in) :: beta
                code = 0.5d0
            end function
            
            public static double code(double alpha, double beta) {
            	return 0.5;
            }
            
            def code(alpha, beta):
            	return 0.5
            
            function code(alpha, beta)
            	return 0.5
            end
            
            function tmp = code(alpha, beta)
            	tmp = 0.5;
            end
            
            code[alpha_, beta_] := 0.5
            
            \begin{array}{l}
            
            \\
            0.5
            \end{array}
            
            Derivation
            1. Initial program 78.6%

              \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
            2. Add Preprocessing
            3. Taylor expanded in alpha around 0

              \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\color{blue}{\left(\frac{\beta}{2 + \beta}\right)}, 1\right), 2\right) \]
            4. Step-by-step derivation
              1. /-lowering-/.f64N/A

                \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \left(2 + \beta\right)\right), 1\right), 2\right) \]
              2. +-lowering-+.f6476.9%

                \[\leadsto \mathsf{/.f64}\left(\mathsf{+.f64}\left(\mathsf{/.f64}\left(\beta, \mathsf{+.f64}\left(2, \beta\right)\right), 1\right), 2\right) \]
            5. Simplified76.9%

              \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
            6. Taylor expanded in beta around 0

              \[\leadsto \color{blue}{\frac{1}{2}} \]
            7. Step-by-step derivation
              1. Simplified51.9%

                \[\leadsto \color{blue}{0.5} \]
              2. Add Preprocessing

              Reproduce

              ?
              herbie shell --seed 2024138 
              (FPCore (alpha beta)
                :name "Octave 3.8, jcobi/1"
                :precision binary64
                :pre (and (> alpha -1.0) (> beta -1.0))
                (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))