Octave 3.8, jcobi/1

Percentage Accurate: 75.3% → 99.7%
Time: 8.5s
Alternatives: 15
Speedup: 0.7×

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 15 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: 75.3% 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: 99.7% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\frac{\mathsf{fma}\left(\beta + 2, \frac{\mathsf{fma}\left(\beta, -2, -2\right)}{\alpha}, \mathsf{fma}\left(2, \beta, 2\right)\right)}{\alpha}}{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}{2}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) -0.5)
   (/
    (/
     (fma (+ beta 2.0) (/ (fma beta -2.0 -2.0) alpha) (fma 2.0 beta 2.0))
     alpha)
    2.0)
   (/ (fma (/ -1.0 (- -2.0 (+ beta alpha))) (- beta alpha) 1.0) 2.0)))
double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.5) {
		tmp = (fma((beta + 2.0), (fma(beta, -2.0, -2.0) / alpha), fma(2.0, beta, 2.0)) / alpha) / 2.0;
	} else {
		tmp = fma((-1.0 / (-2.0 - (beta + alpha))), (beta - alpha), 1.0) / 2.0;
	}
	return tmp;
}
function code(alpha, beta)
	tmp = 0.0
	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= -0.5)
		tmp = Float64(Float64(fma(Float64(beta + 2.0), Float64(fma(beta, -2.0, -2.0) / alpha), fma(2.0, beta, 2.0)) / alpha) / 2.0);
	else
		tmp = Float64(fma(Float64(-1.0 / Float64(-2.0 - Float64(beta + alpha))), Float64(beta - alpha), 1.0) / 2.0);
	end
	return tmp
end
code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], N[(N[(N[(N[(beta + 2.0), $MachinePrecision] * N[(N[(beta * -2.0 + -2.0), $MachinePrecision] / alpha), $MachinePrecision] + N[(2.0 * beta + 2.0), $MachinePrecision]), $MachinePrecision] / alpha), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(N[(-1.0 / N[(-2.0 - N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(beta - alpha), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\
\;\;\;\;\frac{\frac{\mathsf{fma}\left(\beta + 2, \frac{\mathsf{fma}\left(\beta, -2, -2\right)}{\alpha}, \mathsf{fma}\left(2, \beta, 2\right)\right)}{\alpha}}{2}\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}{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 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{\left(2 + \left(-1 \cdot \frac{{\left(2 + \beta\right)}^{2}}{\alpha} + 2 \cdot \beta\right)\right) - \frac{\beta \cdot \left(2 + \beta\right)}{\alpha}}{\alpha}}}{2} \]
    5. Simplified99.6%

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

    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. Step-by-step derivation
      1. lift-+.f64N/A

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

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

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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}} + 1}{2} \]
      6. clear-numN/A

        \[\leadsto \frac{\color{blue}{\frac{1}{\frac{\left(\alpha + \beta\right) + 2}{\beta - \alpha}}} + 1}{2} \]
      7. associate-/r/N/A

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

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{1}{\left(\alpha + \beta\right) + 2}, \beta - \alpha, 1\right)}}{2} \]
      9. frac-2negN/A

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\left(\left(\alpha + \beta\right) + 2\right)\right)}}, \beta - \alpha, 1\right)}{2} \]
      10. metadata-evalN/A

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

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

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\mathsf{neg}\left(\color{blue}{\left(\left(\alpha + \beta\right) + 2\right)}\right)}, \beta - \alpha, 1\right)}{2} \]
      13. +-commutativeN/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\mathsf{neg}\left(\color{blue}{\left(2 + \left(\alpha + \beta\right)\right)}\right)}, \beta - \alpha, 1\right)}{2} \]
      14. distribute-neg-inN/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{\left(\mathsf{neg}\left(2\right)\right) + \left(\mathsf{neg}\left(\left(\alpha + \beta\right)\right)\right)}}, \beta - \alpha, 1\right)}{2} \]
      15. unsub-negN/A

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

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{\left(\mathsf{neg}\left(2\right)\right) - \left(\alpha + \beta\right)}}, \beta - \alpha, 1\right)}{2} \]
      17. metadata-eval100.0

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{-2} - \left(\alpha + \beta\right)}, \beta - \alpha, 1\right)}{2} \]
      18. lift-+.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\alpha + \beta\right)}}, \beta - \alpha, 1\right)}{2} \]
      19. +-commutativeN/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\beta + \alpha\right)}}, \beta - \alpha, 1\right)}{2} \]
      20. lower-+.f64100.0

        \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\beta + \alpha\right)}}, \beta - \alpha, 1\right)}{2} \]
    4. Applied egg-rr100.0%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}}{2} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

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

Alternative 2: 99.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{1}{\frac{\beta + \left(\alpha + 2\right)}{\beta - \alpha}}}{2}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) -0.999998)
   (/ (+ beta 1.0) alpha)
   (/ (+ 1.0 (/ 1.0 (/ (+ beta (+ alpha 2.0)) (- beta alpha)))) 2.0)))
double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.999998) {
		tmp = (beta + 1.0) / alpha;
	} else {
		tmp = (1.0 + (1.0 / ((beta + (alpha + 2.0)) / (beta - alpha)))) / 2.0;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (((beta - alpha) / (2.0d0 + (beta + alpha))) <= (-0.999998d0)) then
        tmp = (beta + 1.0d0) / alpha
    else
        tmp = (1.0d0 + (1.0d0 / ((beta + (alpha + 2.0d0)) / (beta - alpha)))) / 2.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.999998) {
		tmp = (beta + 1.0) / alpha;
	} else {
		tmp = (1.0 + (1.0 / ((beta + (alpha + 2.0)) / (beta - alpha)))) / 2.0;
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if ((beta - alpha) / (2.0 + (beta + alpha))) <= -0.999998:
		tmp = (beta + 1.0) / alpha
	else:
		tmp = (1.0 + (1.0 / ((beta + (alpha + 2.0)) / (beta - alpha)))) / 2.0
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= -0.999998)
		tmp = Float64(Float64(beta + 1.0) / alpha);
	else
		tmp = Float64(Float64(1.0 + Float64(1.0 / Float64(Float64(beta + Float64(alpha + 2.0)) / Float64(beta - alpha)))) / 2.0);
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.999998)
		tmp = (beta + 1.0) / alpha;
	else
		tmp = (1.0 + (1.0 / ((beta + (alpha + 2.0)) / (beta - alpha)))) / 2.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.999998], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(1.0 + N[(1.0 / N[(N[(beta + N[(alpha + 2.0), $MachinePrecision]), $MachinePrecision] / N[(beta - alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\
\;\;\;\;\frac{\beta + 1}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + \frac{1}{\frac{\beta + \left(\alpha + 2\right)}{\beta - \alpha}}}{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))) < -0.999998000000000054

    1. Initial program 7.4%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6499.1

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified99.1%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
      4. distribute-rgt-inN/A

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

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

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
      7. lower-*.f6499.1

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
    8. Simplified99.1%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
    9. Step-by-step derivation
      1. lift-*.f64N/A

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
      4. associate-*r*N/A

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

        \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
      6. *-lft-identityN/A

        \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
      7. lower-+.f6499.1

        \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
    10. Applied egg-rr99.1%

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

    if -0.999998000000000054 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64)))

    1. Initial program 99.8%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-+.f64N/A

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

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

        \[\leadsto \frac{\frac{\color{blue}{\beta - \alpha}}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
      4. clear-numN/A

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

        \[\leadsto \frac{\color{blue}{\frac{1}{\frac{\left(\alpha + \beta\right) + 2}{\beta - \alpha}}} + 1}{2} \]
      6. lower-/.f6499.8

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

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

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

        \[\leadsto \frac{\frac{1}{\frac{\color{blue}{\left(\beta + \alpha\right)} + 2}{\beta - \alpha}} + 1}{2} \]
      10. associate-+l+N/A

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

        \[\leadsto \frac{\frac{1}{\frac{\color{blue}{\beta + \left(\alpha + 2\right)}}{\beta - \alpha}} + 1}{2} \]
      12. lower-+.f6499.8

        \[\leadsto \frac{\frac{1}{\frac{\beta + \color{blue}{\left(\alpha + 2\right)}}{\beta - \alpha}} + 1}{2} \]
    4. Applied egg-rr99.8%

      \[\leadsto \frac{\color{blue}{\frac{1}{\frac{\beta + \left(\alpha + 2\right)}{\beta - \alpha}}} + 1}{2} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + \frac{1}{\frac{\beta + \left(\alpha + 2\right)}{\beta - \alpha}}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 97.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, 0.0625, -0.125\right), 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1 - \alpha}{\beta}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
   (if (<= t_0 -0.5)
     (/ (+ beta 1.0) alpha)
     (if (<= t_0 0.5)
       (fma beta (fma beta (fma beta 0.0625 -0.125) 0.25) 0.5)
       (+ 1.0 (/ (- -1.0 alpha) beta))))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
	double tmp;
	if (t_0 <= -0.5) {
		tmp = (beta + 1.0) / alpha;
	} else if (t_0 <= 0.5) {
		tmp = fma(beta, fma(beta, fma(beta, 0.0625, -0.125), 0.25), 0.5);
	} else {
		tmp = 1.0 + ((-1.0 - alpha) / beta);
	}
	return tmp;
}
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(Float64(beta + 1.0) / alpha);
	elseif (t_0 <= 0.5)
		tmp = fma(beta, fma(beta, fma(beta, 0.0625, -0.125), 0.25), 0.5);
	else
		tmp = Float64(1.0 + Float64(Float64(-1.0 - alpha) / beta));
	end
	return tmp
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * N[(beta * N[(beta * 0.0625 + -0.125), $MachinePrecision] + 0.25), $MachinePrecision] + 0.5), $MachinePrecision], N[(1.0 + N[(N[(-1.0 - alpha), $MachinePrecision] / beta), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, 0.0625, -0.125\right), 0.25\right), 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6498.3

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified98.3%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
      4. distribute-rgt-inN/A

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

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

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
      7. lower-*.f6498.3

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
    8. Simplified98.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
    9. Step-by-step derivation
      1. lift-*.f64N/A

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
      4. associate-*r*N/A

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

        \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
      6. *-lft-identityN/A

        \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
      7. lower-+.f6498.3

        \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
    10. Applied egg-rr98.3%

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

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

    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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.1

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.1%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \beta \cdot \left(\frac{1}{4} + \beta \cdot \left(\frac{1}{16} \cdot \beta - \frac{1}{8}\right)\right)} \]
    7. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\beta \cdot \left(\frac{1}{4} + \beta \cdot \left(\frac{1}{16} \cdot \beta - \frac{1}{8}\right)\right) + \frac{1}{2}} \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{4} + \beta \cdot \left(\frac{1}{16} \cdot \beta - \frac{1}{8}\right), \frac{1}{2}\right)} \]
      3. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \left(\frac{1}{16} \cdot \beta - \frac{1}{8}\right) + \frac{1}{4}}, \frac{1}{2}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{16} \cdot \beta - \frac{1}{8}, \frac{1}{4}\right)}, \frac{1}{2}\right) \]
      5. sub-negN/A

        \[\leadsto \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \color{blue}{\frac{1}{16} \cdot \beta + \left(\mathsf{neg}\left(\frac{1}{8}\right)\right)}, \frac{1}{4}\right), \frac{1}{2}\right) \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \frac{1}{16}} + \left(\mathsf{neg}\left(\frac{1}{8}\right)\right), \frac{1}{4}\right), \frac{1}{2}\right) \]
      7. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \beta \cdot \frac{1}{16} + \color{blue}{\frac{-1}{8}}, \frac{1}{4}\right), \frac{1}{2}\right) \]
      8. lower-fma.f6497.1

        \[\leadsto \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, 0.0625, -0.125\right)}, 0.25\right), 0.5\right) \]
    8. Simplified97.1%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, 0.0625, -0.125\right), 0.25\right), 0.5\right)} \]

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

    1. Initial program 99.9%

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

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

        \[\leadsto \frac{2 + \color{blue}{\left(\mathsf{neg}\left(\frac{2 + 2 \cdot \alpha}{\beta}\right)\right)}}{2} \]
      2. unsub-negN/A

        \[\leadsto \frac{\color{blue}{2 - \frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      3. lower--.f64N/A

        \[\leadsto \frac{\color{blue}{2 - \frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      4. lower-/.f64N/A

        \[\leadsto \frac{2 - \color{blue}{\frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      5. +-commutativeN/A

        \[\leadsto \frac{2 - \frac{\color{blue}{2 \cdot \alpha + 2}}{\beta}}{2} \]
      6. *-commutativeN/A

        \[\leadsto \frac{2 - \frac{\color{blue}{\alpha \cdot 2} + 2}{\beta}}{2} \]
      7. lower-fma.f6498.7

        \[\leadsto \frac{2 - \frac{\color{blue}{\mathsf{fma}\left(\alpha, 2, 2\right)}}{\beta}}{2} \]
    5. Simplified98.7%

      \[\leadsto \frac{\color{blue}{2 - \frac{\mathsf{fma}\left(\alpha, 2, 2\right)}{\beta}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

        \[\leadsto \frac{1}{2} \cdot \left(2 - 2 \cdot \frac{1}{\beta}\right) + \color{blue}{\left(\mathsf{neg}\left(\frac{\alpha}{\beta}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(2 - 2 \cdot \frac{1}{\beta}\right) - \frac{\alpha}{\beta}} \]
      4. sub-negN/A

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

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

        \[\leadsto \left(\color{blue}{1} + \frac{1}{2} \cdot \left(\mathsf{neg}\left(2 \cdot \frac{1}{\beta}\right)\right)\right) - \frac{\alpha}{\beta} \]
      7. associate--l+N/A

        \[\leadsto \color{blue}{1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(2 \cdot \frac{1}{\beta}\right)\right) - \frac{\alpha}{\beta}\right)} \]
      8. associate-*r/N/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{2 \cdot 1}{\beta}}\right)\right) - \frac{\alpha}{\beta}\right) \]
      9. metadata-evalN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(\frac{\color{blue}{2}}{\beta}\right)\right) - \frac{\alpha}{\beta}\right) \]
      10. distribute-neg-fracN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \color{blue}{\frac{\mathsf{neg}\left(2\right)}{\beta}} - \frac{\alpha}{\beta}\right) \]
      11. metadata-evalN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \frac{\color{blue}{-2}}{\beta} - \frac{\alpha}{\beta}\right) \]
      12. associate-*r/N/A

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

        \[\leadsto 1 + \left(\frac{\color{blue}{-1}}{\beta} - \frac{\alpha}{\beta}\right) \]
      14. div-subN/A

        \[\leadsto 1 + \color{blue}{\frac{-1 - \alpha}{\beta}} \]
      15. unsub-negN/A

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

        \[\leadsto 1 + \frac{\color{blue}{\frac{-1}{2} \cdot 2} + \left(\mathsf{neg}\left(\alpha\right)\right)}{\beta} \]
      17. mul-1-negN/A

        \[\leadsto 1 + \frac{\frac{-1}{2} \cdot 2 + \color{blue}{-1 \cdot \alpha}}{\beta} \]
      18. metadata-evalN/A

        \[\leadsto 1 + \frac{\frac{-1}{2} \cdot 2 + \color{blue}{\left(\frac{-1}{2} \cdot 2\right)} \cdot \alpha}{\beta} \]
      19. associate-*r*N/A

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

        \[\leadsto 1 + \frac{\color{blue}{\frac{-1}{2} \cdot \left(2 + 2 \cdot \alpha\right)}}{\beta} \]
    8. Simplified98.7%

      \[\leadsto \color{blue}{1 + \frac{-1 - \alpha}{\beta}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification97.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, 0.0625, -0.125\right), 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1 - \alpha}{\beta}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 97.8% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1 - \alpha}{\beta}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
   (if (<= t_0 -0.5)
     (/ (+ beta 1.0) alpha)
     (if (<= t_0 0.5)
       (fma beta (fma beta -0.125 0.25) 0.5)
       (+ 1.0 (/ (- -1.0 alpha) beta))))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
	double tmp;
	if (t_0 <= -0.5) {
		tmp = (beta + 1.0) / alpha;
	} else if (t_0 <= 0.5) {
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	} else {
		tmp = 1.0 + ((-1.0 - alpha) / beta);
	}
	return tmp;
}
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(Float64(beta + 1.0) / alpha);
	elseif (t_0 <= 0.5)
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	else
		tmp = Float64(1.0 + Float64(Float64(-1.0 - alpha) / beta));
	end
	return tmp
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * N[(beta * -0.125 + 0.25), $MachinePrecision] + 0.5), $MachinePrecision], N[(1.0 + N[(N[(-1.0 - alpha), $MachinePrecision] / beta), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6498.3

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified98.3%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
      4. distribute-rgt-inN/A

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

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

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
      7. lower-*.f6498.3

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
    8. Simplified98.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
    9. Step-by-step derivation
      1. lift-*.f64N/A

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
      4. associate-*r*N/A

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

        \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
      6. *-lft-identityN/A

        \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
      7. lower-+.f6498.3

        \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
    10. Applied egg-rr98.3%

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

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

    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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.1

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.1%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right)} \]
    7. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right) + \frac{1}{2}} \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{4} + \frac{-1}{8} \cdot \beta, \frac{1}{2}\right)} \]
      3. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\frac{-1}{8} \cdot \beta + \frac{1}{4}}, \frac{1}{2}\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \frac{-1}{8}} + \frac{1}{4}, \frac{1}{2}\right) \]
      5. lower-fma.f6496.9

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, -0.125, 0.25\right)}, 0.5\right) \]
    8. Simplified96.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)} \]

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

    1. Initial program 99.9%

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

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

        \[\leadsto \frac{2 + \color{blue}{\left(\mathsf{neg}\left(\frac{2 + 2 \cdot \alpha}{\beta}\right)\right)}}{2} \]
      2. unsub-negN/A

        \[\leadsto \frac{\color{blue}{2 - \frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      3. lower--.f64N/A

        \[\leadsto \frac{\color{blue}{2 - \frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      4. lower-/.f64N/A

        \[\leadsto \frac{2 - \color{blue}{\frac{2 + 2 \cdot \alpha}{\beta}}}{2} \]
      5. +-commutativeN/A

        \[\leadsto \frac{2 - \frac{\color{blue}{2 \cdot \alpha + 2}}{\beta}}{2} \]
      6. *-commutativeN/A

        \[\leadsto \frac{2 - \frac{\color{blue}{\alpha \cdot 2} + 2}{\beta}}{2} \]
      7. lower-fma.f6498.7

        \[\leadsto \frac{2 - \frac{\color{blue}{\mathsf{fma}\left(\alpha, 2, 2\right)}}{\beta}}{2} \]
    5. Simplified98.7%

      \[\leadsto \frac{\color{blue}{2 - \frac{\mathsf{fma}\left(\alpha, 2, 2\right)}{\beta}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

        \[\leadsto \frac{1}{2} \cdot \left(2 - 2 \cdot \frac{1}{\beta}\right) + \color{blue}{\left(\mathsf{neg}\left(\frac{\alpha}{\beta}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(2 - 2 \cdot \frac{1}{\beta}\right) - \frac{\alpha}{\beta}} \]
      4. sub-negN/A

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

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

        \[\leadsto \left(\color{blue}{1} + \frac{1}{2} \cdot \left(\mathsf{neg}\left(2 \cdot \frac{1}{\beta}\right)\right)\right) - \frac{\alpha}{\beta} \]
      7. associate--l+N/A

        \[\leadsto \color{blue}{1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(2 \cdot \frac{1}{\beta}\right)\right) - \frac{\alpha}{\beta}\right)} \]
      8. associate-*r/N/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{2 \cdot 1}{\beta}}\right)\right) - \frac{\alpha}{\beta}\right) \]
      9. metadata-evalN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \left(\mathsf{neg}\left(\frac{\color{blue}{2}}{\beta}\right)\right) - \frac{\alpha}{\beta}\right) \]
      10. distribute-neg-fracN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \color{blue}{\frac{\mathsf{neg}\left(2\right)}{\beta}} - \frac{\alpha}{\beta}\right) \]
      11. metadata-evalN/A

        \[\leadsto 1 + \left(\frac{1}{2} \cdot \frac{\color{blue}{-2}}{\beta} - \frac{\alpha}{\beta}\right) \]
      12. associate-*r/N/A

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

        \[\leadsto 1 + \left(\frac{\color{blue}{-1}}{\beta} - \frac{\alpha}{\beta}\right) \]
      14. div-subN/A

        \[\leadsto 1 + \color{blue}{\frac{-1 - \alpha}{\beta}} \]
      15. unsub-negN/A

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

        \[\leadsto 1 + \frac{\color{blue}{\frac{-1}{2} \cdot 2} + \left(\mathsf{neg}\left(\alpha\right)\right)}{\beta} \]
      17. mul-1-negN/A

        \[\leadsto 1 + \frac{\frac{-1}{2} \cdot 2 + \color{blue}{-1 \cdot \alpha}}{\beta} \]
      18. metadata-evalN/A

        \[\leadsto 1 + \frac{\frac{-1}{2} \cdot 2 + \color{blue}{\left(\frac{-1}{2} \cdot 2\right)} \cdot \alpha}{\beta} \]
      19. associate-*r*N/A

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

        \[\leadsto 1 + \frac{\color{blue}{\frac{-1}{2} \cdot \left(2 + 2 \cdot \alpha\right)}}{\beta} \]
    8. Simplified98.7%

      \[\leadsto \color{blue}{1 + \frac{-1 - \alpha}{\beta}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification97.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1 - \alpha}{\beta}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 97.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
   (if (<= t_0 -0.5)
     (/ (+ beta 1.0) alpha)
     (if (<= t_0 0.5)
       (fma beta (fma beta -0.125 0.25) 0.5)
       (+ 1.0 (/ -1.0 beta))))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
	double tmp;
	if (t_0 <= -0.5) {
		tmp = (beta + 1.0) / alpha;
	} else if (t_0 <= 0.5) {
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	} else {
		tmp = 1.0 + (-1.0 / beta);
	}
	return tmp;
}
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(Float64(beta + 1.0) / alpha);
	elseif (t_0 <= 0.5)
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	else
		tmp = Float64(1.0 + Float64(-1.0 / beta));
	end
	return tmp
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * N[(beta * -0.125 + 0.25), $MachinePrecision] + 0.5), $MachinePrecision], N[(1.0 + N[(-1.0 / beta), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6498.3

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified98.3%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in alpha around 0

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

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
      4. distribute-rgt-inN/A

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

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

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
      7. lower-*.f6498.3

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
    8. Simplified98.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
    9. Step-by-step derivation
      1. lift-*.f64N/A

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
      4. associate-*r*N/A

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

        \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
      6. *-lft-identityN/A

        \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
      7. lower-+.f6498.3

        \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
    10. Applied egg-rr98.3%

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

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

    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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.1

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.1%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right)} \]
    7. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right) + \frac{1}{2}} \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{4} + \frac{-1}{8} \cdot \beta, \frac{1}{2}\right)} \]
      3. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\frac{-1}{8} \cdot \beta + \frac{1}{4}}, \frac{1}{2}\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \frac{-1}{8}} + \frac{1}{4}, \frac{1}{2}\right) \]
      5. lower-fma.f6496.9

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, -0.125, 0.25\right)}, 0.5\right) \]
    8. Simplified96.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)} \]

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

    1. Initial program 99.9%

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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.9

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.9%

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

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

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

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

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

        \[\leadsto 1 + \frac{\color{blue}{-1}}{\beta} \]
      5. lower-/.f6498.0

        \[\leadsto 1 + \color{blue}{\frac{-1}{\beta}} \]
    8. Simplified98.0%

      \[\leadsto \color{blue}{1 + \frac{-1}{\beta}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification97.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 92.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
   (if (<= t_0 -0.5)
     (/ 1.0 alpha)
     (if (<= t_0 0.5)
       (fma beta (fma beta -0.125 0.25) 0.5)
       (+ 1.0 (/ -1.0 beta))))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
	double tmp;
	if (t_0 <= -0.5) {
		tmp = 1.0 / alpha;
	} else if (t_0 <= 0.5) {
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	} else {
		tmp = 1.0 + (-1.0 / beta);
	}
	return tmp;
}
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(1.0 / alpha);
	elseif (t_0 <= 0.5)
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	else
		tmp = Float64(1.0 + Float64(-1.0 / beta));
	end
	return tmp
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(1.0 / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * N[(beta * -0.125 + 0.25), $MachinePrecision] + 0.5), $MachinePrecision], N[(1.0 + N[(-1.0 / beta), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6498.3

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified98.3%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
    7. Step-by-step derivation
      1. lower-/.f6475.4

        \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
    8. Simplified75.4%

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

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

    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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.1

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.1%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right)} \]
    7. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right) + \frac{1}{2}} \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{4} + \frac{-1}{8} \cdot \beta, \frac{1}{2}\right)} \]
      3. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\frac{-1}{8} \cdot \beta + \frac{1}{4}}, \frac{1}{2}\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \frac{-1}{8}} + \frac{1}{4}, \frac{1}{2}\right) \]
      5. lower-fma.f6496.9

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, -0.125, 0.25\right)}, 0.5\right) \]
    8. Simplified96.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)} \]

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

    1. Initial program 99.9%

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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.9

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.9%

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

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

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

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

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

        \[\leadsto 1 + \frac{\color{blue}{-1}}{\beta} \]
      5. lower-/.f6498.0

        \[\leadsto 1 + \color{blue}{\frac{-1}{\beta}} \]
    8. Simplified98.0%

      \[\leadsto \color{blue}{1 + \frac{-1}{\beta}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification91.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{\beta}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 92.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
   (if (<= t_0 -0.5)
     (/ 1.0 alpha)
     (if (<= t_0 0.5) (fma beta (fma beta -0.125 0.25) 0.5) 1.0))))
double code(double alpha, double beta) {
	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
	double tmp;
	if (t_0 <= -0.5) {
		tmp = 1.0 / alpha;
	} else if (t_0 <= 0.5) {
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	} else {
		tmp = 1.0;
	}
	return tmp;
}
function code(alpha, beta)
	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
	tmp = 0.0
	if (t_0 <= -0.5)
		tmp = Float64(1.0 / alpha);
	elseif (t_0 <= 0.5)
		tmp = fma(beta, fma(beta, -0.125, 0.25), 0.5);
	else
		tmp = 1.0;
	end
	return tmp
end
code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(1.0 / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * N[(beta * -0.125 + 0.25), $MachinePrecision] + 0.5), $MachinePrecision], 1.0]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

    1. Initial program 8.3%

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

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

        \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
      3. lower-fma.f6498.3

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
    5. Simplified98.3%

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
    6. Taylor expanded in beta around 0

      \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
    7. Step-by-step derivation
      1. lower-/.f6475.4

        \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
    8. Simplified75.4%

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

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

    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

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

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
      2. lower-+.f6498.1

        \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
    5. Simplified98.1%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right)} \]
    7. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\beta \cdot \left(\frac{1}{4} + \frac{-1}{8} \cdot \beta\right) + \frac{1}{2}} \]
      2. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \frac{1}{4} + \frac{-1}{8} \cdot \beta, \frac{1}{2}\right)} \]
      3. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\frac{-1}{8} \cdot \beta + \frac{1}{4}}, \frac{1}{2}\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\beta \cdot \frac{-1}{8}} + \frac{1}{4}, \frac{1}{2}\right) \]
      5. lower-fma.f6496.9

        \[\leadsto \mathsf{fma}\left(\beta, \color{blue}{\mathsf{fma}\left(\beta, -0.125, 0.25\right)}, 0.5\right) \]
    8. Simplified96.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)} \]

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

    1. Initial program 99.9%

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

      \[\leadsto \frac{\color{blue}{2}}{2} \]
    4. Step-by-step derivation
      1. Simplified97.8%

        \[\leadsto \frac{\color{blue}{2}}{2} \]
      2. Step-by-step derivation
        1. metadata-eval97.8

          \[\leadsto \color{blue}{1} \]
      3. Applied egg-rr97.8%

        \[\leadsto \color{blue}{1} \]
    5. Recombined 3 regimes into one program.
    6. Final simplification91.3%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, \mathsf{fma}\left(\beta, -0.125, 0.25\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
    7. Add Preprocessing

    Alternative 8: 99.7% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}{2}\\ \end{array} \end{array} \]
    (FPCore (alpha beta)
     :precision binary64
     (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) -0.999998)
       (/ (+ beta 1.0) alpha)
       (/ (fma (/ -1.0 (- -2.0 (+ beta alpha))) (- beta alpha) 1.0) 2.0)))
    double code(double alpha, double beta) {
    	double tmp;
    	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.999998) {
    		tmp = (beta + 1.0) / alpha;
    	} else {
    		tmp = fma((-1.0 / (-2.0 - (beta + alpha))), (beta - alpha), 1.0) / 2.0;
    	}
    	return tmp;
    }
    
    function code(alpha, beta)
    	tmp = 0.0
    	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= -0.999998)
    		tmp = Float64(Float64(beta + 1.0) / alpha);
    	else
    		tmp = Float64(fma(Float64(-1.0 / Float64(-2.0 - Float64(beta + alpha))), Float64(beta - alpha), 1.0) / 2.0);
    	end
    	return tmp
    end
    
    code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.999998], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(N[(-1.0 / N[(-2.0 - N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(beta - alpha), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\
    \;\;\;\;\frac{\beta + 1}{\alpha}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}{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))) < -0.999998000000000054

      1. Initial program 7.4%

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

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

          \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
        3. lower-fma.f6499.1

          \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
      5. Simplified99.1%

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
      6. Taylor expanded in alpha around 0

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

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
        4. distribute-rgt-inN/A

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

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

          \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
        7. lower-*.f6499.1

          \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
      8. Simplified99.1%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
      9. Step-by-step derivation
        1. lift-*.f64N/A

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
        4. associate-*r*N/A

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

          \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
        6. *-lft-identityN/A

          \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
        7. lower-+.f6499.1

          \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
      10. Applied egg-rr99.1%

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

      if -0.999998000000000054 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64)))

      1. Initial program 99.8%

        \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-+.f64N/A

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

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

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

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

          \[\leadsto \frac{\color{blue}{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}} + 1}{2} \]
        6. clear-numN/A

          \[\leadsto \frac{\color{blue}{\frac{1}{\frac{\left(\alpha + \beta\right) + 2}{\beta - \alpha}}} + 1}{2} \]
        7. associate-/r/N/A

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

          \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{1}{\left(\alpha + \beta\right) + 2}, \beta - \alpha, 1\right)}}{2} \]
        9. frac-2negN/A

          \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\left(\left(\alpha + \beta\right) + 2\right)\right)}}, \beta - \alpha, 1\right)}{2} \]
        10. metadata-evalN/A

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

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

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\mathsf{neg}\left(\color{blue}{\left(\left(\alpha + \beta\right) + 2\right)}\right)}, \beta - \alpha, 1\right)}{2} \]
        13. +-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\mathsf{neg}\left(\color{blue}{\left(2 + \left(\alpha + \beta\right)\right)}\right)}, \beta - \alpha, 1\right)}{2} \]
        14. distribute-neg-inN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{\left(\mathsf{neg}\left(2\right)\right) + \left(\mathsf{neg}\left(\left(\alpha + \beta\right)\right)\right)}}, \beta - \alpha, 1\right)}{2} \]
        15. unsub-negN/A

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

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{\left(\mathsf{neg}\left(2\right)\right) - \left(\alpha + \beta\right)}}, \beta - \alpha, 1\right)}{2} \]
        17. metadata-eval99.8

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{\color{blue}{-2} - \left(\alpha + \beta\right)}, \beta - \alpha, 1\right)}{2} \]
        18. lift-+.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\alpha + \beta\right)}}, \beta - \alpha, 1\right)}{2} \]
        19. +-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\beta + \alpha\right)}}, \beta - \alpha, 1\right)}{2} \]
        20. lower-+.f6499.8

          \[\leadsto \frac{\mathsf{fma}\left(\frac{-1}{-2 - \color{blue}{\left(\beta + \alpha\right)}}, \beta - \alpha, 1\right)}{2} \]
      4. Applied egg-rr99.8%

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}}{2} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification99.6%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{-1}{-2 - \left(\beta + \alpha\right)}, \beta - \alpha, 1\right)}{2}\\ \end{array} \]
    5. Add Preprocessing

    Alternative 9: 99.7% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{t\_0 + 1}{2}\\ \end{array} \end{array} \]
    (FPCore (alpha beta)
     :precision binary64
     (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
       (if (<= t_0 -0.999998) (/ (+ beta 1.0) alpha) (/ (+ t_0 1.0) 2.0))))
    double code(double alpha, double beta) {
    	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
    	double tmp;
    	if (t_0 <= -0.999998) {
    		tmp = (beta + 1.0) / 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) / (2.0d0 + (beta + alpha))
        if (t_0 <= (-0.999998d0)) then
            tmp = (beta + 1.0d0) / 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) / (2.0 + (beta + alpha));
    	double tmp;
    	if (t_0 <= -0.999998) {
    		tmp = (beta + 1.0) / alpha;
    	} else {
    		tmp = (t_0 + 1.0) / 2.0;
    	}
    	return tmp;
    }
    
    def code(alpha, beta):
    	t_0 = (beta - alpha) / (2.0 + (beta + alpha))
    	tmp = 0
    	if t_0 <= -0.999998:
    		tmp = (beta + 1.0) / alpha
    	else:
    		tmp = (t_0 + 1.0) / 2.0
    	return tmp
    
    function code(alpha, beta)
    	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
    	tmp = 0.0
    	if (t_0 <= -0.999998)
    		tmp = Float64(Float64(beta + 1.0) / 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) / (2.0 + (beta + alpha));
    	tmp = 0.0;
    	if (t_0 <= -0.999998)
    		tmp = (beta + 1.0) / 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[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.999998], N[(N[(beta + 1.0), $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}{2 + \left(\beta + \alpha\right)}\\
    \mathbf{if}\;t\_0 \leq -0.999998:\\
    \;\;\;\;\frac{\beta + 1}{\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))) < -0.999998000000000054

      1. Initial program 7.4%

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

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

          \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
        3. lower-fma.f6499.1

          \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
      5. Simplified99.1%

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
      6. Taylor expanded in alpha around 0

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

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
        4. distribute-rgt-inN/A

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

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

          \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
        7. lower-*.f6499.1

          \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
      8. Simplified99.1%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
      9. Step-by-step derivation
        1. lift-*.f64N/A

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
        4. associate-*r*N/A

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

          \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
        6. *-lft-identityN/A

          \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
        7. lower-+.f6499.1

          \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
      10. Applied egg-rr99.1%

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

      if -0.999998000000000054 < (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64)))

      1. Initial program 99.8%

        \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
      2. Add Preprocessing
    3. Recombined 2 regimes into one program.
    4. Final simplification99.6%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.999998:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} + 1}{2}\\ \end{array} \]
    5. Add Preprocessing

    Alternative 10: 92.3% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\ \mathbf{if}\;t\_0 \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, 0.25, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
    (FPCore (alpha beta)
     :precision binary64
     (let* ((t_0 (/ (- beta alpha) (+ 2.0 (+ beta alpha)))))
       (if (<= t_0 -0.5) (/ 1.0 alpha) (if (<= t_0 0.5) (fma beta 0.25 0.5) 1.0))))
    double code(double alpha, double beta) {
    	double t_0 = (beta - alpha) / (2.0 + (beta + alpha));
    	double tmp;
    	if (t_0 <= -0.5) {
    		tmp = 1.0 / alpha;
    	} else if (t_0 <= 0.5) {
    		tmp = fma(beta, 0.25, 0.5);
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    function code(alpha, beta)
    	t_0 = Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha)))
    	tmp = 0.0
    	if (t_0 <= -0.5)
    		tmp = Float64(1.0 / alpha);
    	elseif (t_0 <= 0.5)
    		tmp = fma(beta, 0.25, 0.5);
    	else
    		tmp = 1.0;
    	end
    	return tmp
    end
    
    code[alpha_, beta_] := Block[{t$95$0 = N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.5], N[(1.0 / alpha), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(beta * 0.25 + 0.5), $MachinePrecision], 1.0]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)}\\
    \mathbf{if}\;t\_0 \leq -0.5:\\
    \;\;\;\;\frac{1}{\alpha}\\
    
    \mathbf{elif}\;t\_0 \leq 0.5:\\
    \;\;\;\;\mathsf{fma}\left(\beta, 0.25, 0.5\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;1\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (/.f64 (-.f64 beta alpha) (+.f64 (+.f64 alpha beta) #s(literal 2 binary64))) < -0.5

      1. Initial program 8.3%

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

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

          \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
        3. lower-fma.f6498.3

          \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
      5. Simplified98.3%

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
      6. Taylor expanded in beta around 0

        \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
      7. Step-by-step derivation
        1. lower-/.f6475.4

          \[\leadsto \color{blue}{\frac{1}{\alpha}} \]
      8. Simplified75.4%

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

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

      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

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

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        2. lower-+.f6498.1

          \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
      5. Simplified98.1%

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

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

          \[\leadsto \color{blue}{\frac{1}{4} \cdot \beta + \frac{1}{2}} \]
        2. *-commutativeN/A

          \[\leadsto \color{blue}{\beta \cdot \frac{1}{4}} + \frac{1}{2} \]
        3. lower-fma.f6496.4

          \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, 0.25, 0.5\right)} \]
      8. Simplified96.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, 0.25, 0.5\right)} \]

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

      1. Initial program 99.9%

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

        \[\leadsto \frac{\color{blue}{2}}{2} \]
      4. Step-by-step derivation
        1. Simplified97.8%

          \[\leadsto \frac{\color{blue}{2}}{2} \]
        2. Step-by-step derivation
          1. metadata-eval97.8

            \[\leadsto \color{blue}{1} \]
        3. Applied egg-rr97.8%

          \[\leadsto \color{blue}{1} \]
      5. Recombined 3 regimes into one program.
      6. Final simplification91.1%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{1}{\alpha}\\ \mathbf{elif}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(\beta, 0.25, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
      7. Add Preprocessing

      Alternative 11: 98.1% accurate, 0.7× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right) \cdot 0.5\\ \end{array} \end{array} \]
      (FPCore (alpha beta)
       :precision binary64
       (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) -0.5)
         (/ (+ beta 1.0) alpha)
         (* (fma (/ 1.0 (+ beta 2.0)) beta 1.0) 0.5)))
      double code(double alpha, double beta) {
      	double tmp;
      	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.5) {
      		tmp = (beta + 1.0) / alpha;
      	} else {
      		tmp = fma((1.0 / (beta + 2.0)), beta, 1.0) * 0.5;
      	}
      	return tmp;
      }
      
      function code(alpha, beta)
      	tmp = 0.0
      	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= -0.5)
      		tmp = Float64(Float64(beta + 1.0) / alpha);
      	else
      		tmp = Float64(fma(Float64(1.0 / Float64(beta + 2.0)), beta, 1.0) * 0.5);
      	end
      	return tmp
      end
      
      code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(N[(1.0 / N[(beta + 2.0), $MachinePrecision]), $MachinePrecision] * beta + 1.0), $MachinePrecision] * 0.5), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\
      \;\;\;\;\frac{\beta + 1}{\alpha}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right) \cdot 0.5\\
      
      
      \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 8.3%

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

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

            \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
          2. +-commutativeN/A

            \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
          3. lower-fma.f6498.3

            \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
        5. Simplified98.3%

          \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
        6. Taylor expanded in alpha around 0

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

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
          4. distribute-rgt-inN/A

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

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

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
          7. lower-*.f6498.3

            \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
        8. Simplified98.3%

          \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
        9. Step-by-step derivation
          1. lift-*.f64N/A

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
          4. associate-*r*N/A

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

            \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
          6. *-lft-identityN/A

            \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
          7. lower-+.f6498.3

            \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
        10. Applied egg-rr98.3%

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

        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. Taylor expanded in alpha around 0

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

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
          2. lower-+.f6498.4

            \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
        5. Simplified98.4%

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        6. Step-by-step derivation
          1. lift-+.f64N/A

            \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
          2. lift-/.f64N/A

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
          3. lift-+.f64N/A

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta} + 1}}{2} \]
          4. div-invN/A

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

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

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

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

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

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

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

            \[\leadsto \left(1 + \frac{\beta}{\color{blue}{\beta + 2}}\right) \cdot \frac{1}{2} \]
          12. metadata-eval98.4

            \[\leadsto \left(1 + \frac{\beta}{\beta + 2}\right) \cdot \color{blue}{0.5} \]
        7. Applied egg-rr98.4%

          \[\leadsto \color{blue}{\left(1 + \frac{\beta}{\beta + 2}\right) \cdot 0.5} \]
        8. Step-by-step derivation
          1. lift-+.f64N/A

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

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

            \[\leadsto \left(1 + \beta \cdot \color{blue}{\frac{1}{\beta + 2}}\right) \cdot \frac{1}{2} \]
          4. *-commutativeN/A

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

            \[\leadsto \color{blue}{\left(\frac{1}{\beta + 2} \cdot \beta + 1\right)} \cdot \frac{1}{2} \]
          6. lift-fma.f6498.4

            \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right)} \cdot 0.5 \]
        9. Applied egg-rr98.4%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right)} \cdot 0.5 \]
      3. Recombined 2 regimes into one program.
      4. Final simplification98.4%

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

      Alternative 12: 98.1% accurate, 0.7× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\ \;\;\;\;\frac{\beta + 1}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{\beta}{\beta + 2}, 0.5, 0.5\right)\\ \end{array} \end{array} \]
      (FPCore (alpha beta)
       :precision binary64
       (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) -0.5)
         (/ (+ beta 1.0) alpha)
         (fma (/ beta (+ beta 2.0)) 0.5 0.5)))
      double code(double alpha, double beta) {
      	double tmp;
      	if (((beta - alpha) / (2.0 + (beta + alpha))) <= -0.5) {
      		tmp = (beta + 1.0) / alpha;
      	} else {
      		tmp = fma((beta / (beta + 2.0)), 0.5, 0.5);
      	}
      	return tmp;
      }
      
      function code(alpha, beta)
      	tmp = 0.0
      	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= -0.5)
      		tmp = Float64(Float64(beta + 1.0) / alpha);
      	else
      		tmp = fma(Float64(beta / Float64(beta + 2.0)), 0.5, 0.5);
      	end
      	return tmp
      end
      
      code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], N[(N[(beta + 1.0), $MachinePrecision] / alpha), $MachinePrecision], N[(N[(beta / N[(beta + 2.0), $MachinePrecision]), $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq -0.5:\\
      \;\;\;\;\frac{\beta + 1}{\alpha}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(\frac{\beta}{\beta + 2}, 0.5, 0.5\right)\\
      
      
      \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 8.3%

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

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

            \[\leadsto \frac{\color{blue}{\frac{2 + 2 \cdot \beta}{\alpha}}}{2} \]
          2. +-commutativeN/A

            \[\leadsto \frac{\frac{\color{blue}{2 \cdot \beta + 2}}{\alpha}}{2} \]
          3. lower-fma.f6498.3

            \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(2, \beta, 2\right)}}{\alpha}}{2} \]
        5. Simplified98.3%

          \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(2, \beta, 2\right)}{\alpha}}}{2} \]
        6. Taylor expanded in alpha around 0

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

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta + 2\right)}}{\alpha} \]
          4. distribute-rgt-inN/A

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

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

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(2 \cdot \beta, \frac{1}{2}, 1\right)}}{\alpha} \]
          7. lower-*.f6498.3

            \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{2 \cdot \beta}, 0.5, 1\right)}{\alpha} \]
        8. Simplified98.3%

          \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(2 \cdot \beta, 0.5, 1\right)}{\alpha}} \]
        9. Step-by-step derivation
          1. lift-*.f64N/A

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\left(2 \cdot \beta\right)} + 1}{\alpha} \]
          4. associate-*r*N/A

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

            \[\leadsto \frac{\color{blue}{1} \cdot \beta + 1}{\alpha} \]
          6. *-lft-identityN/A

            \[\leadsto \frac{\color{blue}{\beta} + 1}{\alpha} \]
          7. lower-+.f6498.3

            \[\leadsto \frac{\color{blue}{\beta + 1}}{\alpha} \]
        10. Applied egg-rr98.3%

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

        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. Taylor expanded in alpha around 0

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

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
          2. lower-+.f6498.4

            \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
        5. Simplified98.4%

          \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
        6. Step-by-step derivation
          1. lift-+.f64N/A

            \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
          2. clear-numN/A

            \[\leadsto \frac{\color{blue}{\frac{1}{\frac{2 + \beta}{\beta}}} + 1}{2} \]
          3. associate-/r/N/A

            \[\leadsto \frac{\color{blue}{\frac{1}{2 + \beta} \cdot \beta} + 1}{2} \]
          4. lower-fma.f64N/A

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{1}{2 + \beta}, \beta, 1\right)}}{2} \]
          5. lower-/.f6498.4

            \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{1}{2 + \beta}}, \beta, 1\right)}{2} \]
          6. lift-+.f64N/A

            \[\leadsto \frac{\mathsf{fma}\left(\frac{1}{\color{blue}{2 + \beta}}, \beta, 1\right)}{2} \]
          7. +-commutativeN/A

            \[\leadsto \frac{\mathsf{fma}\left(\frac{1}{\color{blue}{\beta + 2}}, \beta, 1\right)}{2} \]
          8. lower-+.f6498.4

            \[\leadsto \frac{\mathsf{fma}\left(\frac{1}{\color{blue}{\beta + 2}}, \beta, 1\right)}{2} \]
        7. Applied egg-rr98.4%

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

            \[\leadsto \frac{\frac{1}{\color{blue}{\beta + 2}} \cdot \beta + 1}{2} \]
          2. frac-2negN/A

            \[\leadsto \frac{\color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\left(\beta + 2\right)\right)}} \cdot \beta + 1}{2} \]
          3. metadata-evalN/A

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

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

            \[\leadsto \frac{\color{blue}{\frac{1}{\beta + 2}} \cdot \beta + 1}{2} \]
          6. lift-/.f64N/A

            \[\leadsto \frac{\color{blue}{\frac{1}{\beta + 2}} \cdot \beta + 1}{2} \]
          7. lift-fma.f64N/A

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right)}}{2} \]
          8. clear-numN/A

            \[\leadsto \color{blue}{\frac{1}{\frac{2}{\mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right)}}} \]
          9. associate-/r/N/A

            \[\leadsto \color{blue}{\frac{1}{2} \cdot \mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right)} \]
          10. metadata-evalN/A

            \[\leadsto \color{blue}{\frac{1}{2}} \cdot \mathsf{fma}\left(\frac{1}{\beta + 2}, \beta, 1\right) \]
          11. lift-fma.f64N/A

            \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\frac{1}{\beta + 2} \cdot \beta + 1\right)} \]
          12. *-commutativeN/A

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

            \[\leadsto \frac{1}{2} \cdot \left(\beta \cdot \color{blue}{\frac{1}{\beta + 2}} + 1\right) \]
          14. div-invN/A

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

            \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\frac{\beta}{\beta + 2}} + 1\right) \]
          16. distribute-rgt-inN/A

            \[\leadsto \color{blue}{\frac{\beta}{\beta + 2} \cdot \frac{1}{2} + 1 \cdot \frac{1}{2}} \]
          17. metadata-evalN/A

            \[\leadsto \frac{\beta}{\beta + 2} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}} \]
          18. lower-fma.f6498.4

            \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{\beta}{\beta + 2}, 0.5, 0.5\right)} \]
        9. Applied egg-rr98.4%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{\beta}{\beta + 2}, 0.5, 0.5\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification98.4%

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

      Alternative 13: 71.9% accurate, 1.3× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
      (FPCore (alpha beta)
       :precision binary64
       (if (<= (/ (- beta alpha) (+ 2.0 (+ beta alpha))) 0.5) 0.5 1.0))
      double code(double alpha, double beta) {
      	double tmp;
      	if (((beta - alpha) / (2.0 + (beta + alpha))) <= 0.5) {
      		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 - alpha) / (2.0d0 + (beta + alpha))) <= 0.5d0) 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 - alpha) / (2.0 + (beta + alpha))) <= 0.5) {
      		tmp = 0.5;
      	} else {
      		tmp = 1.0;
      	}
      	return tmp;
      }
      
      def code(alpha, beta):
      	tmp = 0
      	if ((beta - alpha) / (2.0 + (beta + alpha))) <= 0.5:
      		tmp = 0.5
      	else:
      		tmp = 1.0
      	return tmp
      
      function code(alpha, beta)
      	tmp = 0.0
      	if (Float64(Float64(beta - alpha) / Float64(2.0 + Float64(beta + alpha))) <= 0.5)
      		tmp = 0.5;
      	else
      		tmp = 1.0;
      	end
      	return tmp
      end
      
      function tmp_2 = code(alpha, beta)
      	tmp = 0.0;
      	if (((beta - alpha) / (2.0 + (beta + alpha))) <= 0.5)
      		tmp = 0.5;
      	else
      		tmp = 1.0;
      	end
      	tmp_2 = tmp;
      end
      
      code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(2.0 + N[(beta + alpha), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.5], 0.5, 1.0]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{\beta - \alpha}{2 + \left(\beta + \alpha\right)} \leq 0.5:\\
      \;\;\;\;0.5\\
      
      \mathbf{else}:\\
      \;\;\;\;1\\
      
      
      \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 64.7%

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

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

            \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
          2. lower-+.f6462.6

            \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
        5. Simplified62.6%

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

          \[\leadsto \color{blue}{\frac{1}{2}} \]
        7. Step-by-step derivation
          1. Simplified60.5%

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

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

          1. Initial program 99.9%

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

            \[\leadsto \frac{\color{blue}{2}}{2} \]
          4. Step-by-step derivation
            1. Simplified97.8%

              \[\leadsto \frac{\color{blue}{2}}{2} \]
            2. Step-by-step derivation
              1. metadata-eval97.8

                \[\leadsto \color{blue}{1} \]
            3. Applied egg-rr97.8%

              \[\leadsto \color{blue}{1} \]
          5. Recombined 2 regimes into one program.
          6. Final simplification71.3%

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

          Alternative 14: 72.4% accurate, 2.7× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 2:\\ \;\;\;\;\mathsf{fma}\left(\beta, 0.25, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
          (FPCore (alpha beta)
           :precision binary64
           (if (<= beta 2.0) (fma beta 0.25 0.5) 1.0))
          double code(double alpha, double beta) {
          	double tmp;
          	if (beta <= 2.0) {
          		tmp = fma(beta, 0.25, 0.5);
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          function code(alpha, beta)
          	tmp = 0.0
          	if (beta <= 2.0)
          		tmp = fma(beta, 0.25, 0.5);
          	else
          		tmp = 1.0;
          	end
          	return tmp
          end
          
          code[alpha_, beta_] := If[LessEqual[beta, 2.0], N[(beta * 0.25 + 0.5), $MachinePrecision], 1.0]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;\beta \leq 2:\\
          \;\;\;\;\mathsf{fma}\left(\beta, 0.25, 0.5\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if beta < 2

            1. Initial program 71.0%

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

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

                \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
              2. lower-+.f6468.4

                \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
            5. Simplified68.4%

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

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

                \[\leadsto \color{blue}{\frac{1}{4} \cdot \beta + \frac{1}{2}} \]
              2. *-commutativeN/A

                \[\leadsto \color{blue}{\beta \cdot \frac{1}{4}} + \frac{1}{2} \]
              3. lower-fma.f6467.2

                \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, 0.25, 0.5\right)} \]
            8. Simplified67.2%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\beta, 0.25, 0.5\right)} \]

            if 2 < beta

            1. Initial program 82.0%

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

              \[\leadsto \frac{\color{blue}{2}}{2} \]
            4. Step-by-step derivation
              1. Simplified80.7%

                \[\leadsto \frac{\color{blue}{2}}{2} \]
              2. Step-by-step derivation
                1. metadata-eval80.7

                  \[\leadsto \color{blue}{1} \]
              3. Applied egg-rr80.7%

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

            Alternative 15: 49.7% accurate, 35.0× 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 74.9%

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

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

                \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta}} + 1}{2} \]
              2. lower-+.f6473.1

                \[\leadsto \frac{\frac{\beta}{\color{blue}{2 + \beta}} + 1}{2} \]
            5. Simplified73.1%

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

              \[\leadsto \color{blue}{\frac{1}{2}} \]
            7. Step-by-step derivation
              1. Simplified48.4%

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

              Reproduce

              ?
              herbie shell --seed 2024219 
              (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))