Octave 3.8, jcobi/1

Percentage Accurate: 75.0% → 99.7%
Time: 11.6s
Alternatives: 8
Speedup: 0.9×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 8 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: 75.0% 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, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(\left(\beta + \alpha\right) + 3\right) + -1}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= (/ (- beta alpha) (+ (+ beta alpha) 2.0)) -0.9999999)
   (* -0.5 (/ (- (- -2.0 beta) beta) alpha))
   (+ 0.5 (* (- alpha beta) (/ -0.5 (+ (+ (+ beta alpha) 3.0) -1.0))))))
double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999) {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	} else {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (((beta + alpha) + 3.0) + -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) / ((beta + alpha) + 2.0d0)) <= (-0.9999999d0)) then
        tmp = (-0.5d0) * ((((-2.0d0) - beta) - beta) / alpha)
    else
        tmp = 0.5d0 + ((alpha - beta) * ((-0.5d0) / (((beta + alpha) + 3.0d0) + (-1.0d0))))
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999) {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	} else {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (((beta + alpha) + 3.0) + -1.0)));
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if ((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999:
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha)
	else:
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (((beta + alpha) + 3.0) + -1.0)))
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (Float64(Float64(beta - alpha) / Float64(Float64(beta + alpha) + 2.0)) <= -0.9999999)
		tmp = Float64(-0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) / alpha));
	else
		tmp = Float64(0.5 + Float64(Float64(alpha - beta) * Float64(-0.5 / Float64(Float64(Float64(beta + alpha) + 3.0) + -1.0))));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999)
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	else
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (((beta + alpha) + 3.0) + -1.0)));
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(N[(beta + alpha), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], -0.9999999], N[(-0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision], N[(0.5 + N[(N[(alpha - beta), $MachinePrecision] * N[(-0.5 / N[(N[(N[(beta + alpha), $MachinePrecision] + 3.0), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\
\;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(\left(\beta + \alpha\right) + 3\right) + -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))) < -0.999999900000000053

    1. Initial program 6.5%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative6.5%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub06.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg6.5%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative6.5%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg6.5%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub6.5%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg6.5%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval6.5%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-16.5%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative6.5%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified6.7%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around inf 99.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{-1 \cdot \beta - \left(2 + \beta\right)}{\alpha}} \]
    6. Step-by-step derivation
      1. associate--r+99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta - 2\right) - \beta}}{\alpha} \]
      2. sub-neg99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta + \left(-2\right)\right)} - \beta}{\alpha} \]
      3. neg-mul-199.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{\left(-\beta\right)} + \left(-2\right)\right) - \beta}{\alpha} \]
      4. distribute-neg-in99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-\left(\beta + 2\right)\right)} - \beta}{\alpha} \]
      5. +-commutative99.4%

        \[\leadsto -0.5 \cdot \frac{\left(-\color{blue}{\left(2 + \beta\right)}\right) - \beta}{\alpha} \]
      6. distribute-neg-in99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(\left(-2\right) + \left(-\beta\right)\right)} - \beta}{\alpha} \]
      7. metadata-eval99.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{-2} + \left(-\beta\right)\right) - \beta}{\alpha} \]
      8. unsub-neg99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-2 - \beta\right)} - \beta}{\alpha} \]
    7. Simplified99.4%

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

    if -0.999999900000000053 < (/.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. Step-by-step derivation
      1. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub099.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg99.8%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative99.8%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub99.8%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg99.8%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval99.8%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-199.8%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative99.8%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. associate-+r+99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\left(\beta + \alpha\right) + 2}} \]
      2. expm1-log1p-u96.7%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\left(\beta + \alpha\right) + 2\right)\right)}} \]
      3. expm1-undefine96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{e^{\mathsf{log1p}\left(\left(\beta + \alpha\right) + 2\right)} - 1}} \]
      4. associate-+r+96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{e^{\mathsf{log1p}\left(\color{blue}{\beta + \left(\alpha + 2\right)}\right)} - 1} \]
      5. +-commutative96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{e^{\mathsf{log1p}\left(\color{blue}{\left(\alpha + 2\right) + \beta}\right)} - 1} \]
      6. associate-+l+96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{e^{\mathsf{log1p}\left(\color{blue}{\alpha + \left(2 + \beta\right)}\right)} - 1} \]
    6. Applied egg-rr96.6%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{e^{\mathsf{log1p}\left(\alpha + \left(2 + \beta\right)\right)} - 1}} \]
    7. Step-by-step derivation
      1. sub-neg96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{e^{\mathsf{log1p}\left(\alpha + \left(2 + \beta\right)\right)} + \left(-1\right)}} \]
      2. log1p-undefine96.6%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{e^{\color{blue}{\log \left(1 + \left(\alpha + \left(2 + \beta\right)\right)\right)}} + \left(-1\right)} \]
      3. rem-exp-log99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\left(1 + \left(\alpha + \left(2 + \beta\right)\right)\right)} + \left(-1\right)} \]
      4. associate-+r+99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(1 + \color{blue}{\left(\left(\alpha + 2\right) + \beta\right)}\right) + \left(-1\right)} \]
      5. +-commutative99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(1 + \left(\color{blue}{\left(2 + \alpha\right)} + \beta\right)\right) + \left(-1\right)} \]
      6. associate-+r+99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(1 + \color{blue}{\left(2 + \left(\alpha + \beta\right)\right)}\right) + \left(-1\right)} \]
      7. associate-+r+99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\left(\left(1 + 2\right) + \left(\alpha + \beta\right)\right)} + \left(-1\right)} \]
      8. metadata-eval99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(\color{blue}{3} + \left(\alpha + \beta\right)\right) + \left(-1\right)} \]
      9. +-commutative99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(3 + \color{blue}{\left(\beta + \alpha\right)}\right) + \left(-1\right)} \]
      10. metadata-eval99.8%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(3 + \left(\beta + \alpha\right)\right) + \color{blue}{-1}} \]
    8. Simplified99.8%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\left(3 + \left(\beta + \alpha\right)\right) + -1}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\left(\left(\beta + \alpha\right) + 3\right) + -1}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= (/ (- beta alpha) (+ (+ beta alpha) 2.0)) -0.9999999)
   (* -0.5 (/ (- (- -2.0 beta) beta) alpha))
   (+ 0.5 (* (- alpha beta) (/ -0.5 (+ beta (+ alpha 2.0)))))))
double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999) {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	} else {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (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) / ((beta + alpha) + 2.0d0)) <= (-0.9999999d0)) then
        tmp = (-0.5d0) * ((((-2.0d0) - beta) - beta) / alpha)
    else
        tmp = 0.5d0 + ((alpha - beta) * ((-0.5d0) / (beta + (alpha + 2.0d0))))
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999) {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	} else {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + (alpha + 2.0))));
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if ((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999:
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha)
	else:
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + (alpha + 2.0))))
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (Float64(Float64(beta - alpha) / Float64(Float64(beta + alpha) + 2.0)) <= -0.9999999)
		tmp = Float64(-0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) / alpha));
	else
		tmp = Float64(0.5 + Float64(Float64(alpha - beta) * Float64(-0.5 / Float64(beta + Float64(alpha + 2.0)))));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (((beta - alpha) / ((beta + alpha) + 2.0)) <= -0.9999999)
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	else
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + (alpha + 2.0))));
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[N[(N[(beta - alpha), $MachinePrecision] / N[(N[(beta + alpha), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], -0.9999999], N[(-0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision], N[(0.5 + N[(N[(alpha - beta), $MachinePrecision] * N[(-0.5 / N[(beta + N[(alpha + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\
\;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\

\mathbf{else}:\\
\;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\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))) < -0.999999900000000053

    1. Initial program 6.5%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative6.5%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub06.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg6.5%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg6.5%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative6.5%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg6.5%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub6.5%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg6.5%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval6.5%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-16.5%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative6.5%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/6.5%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified6.7%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around inf 99.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{-1 \cdot \beta - \left(2 + \beta\right)}{\alpha}} \]
    6. Step-by-step derivation
      1. associate--r+99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta - 2\right) - \beta}}{\alpha} \]
      2. sub-neg99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta + \left(-2\right)\right)} - \beta}{\alpha} \]
      3. neg-mul-199.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{\left(-\beta\right)} + \left(-2\right)\right) - \beta}{\alpha} \]
      4. distribute-neg-in99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-\left(\beta + 2\right)\right)} - \beta}{\alpha} \]
      5. +-commutative99.4%

        \[\leadsto -0.5 \cdot \frac{\left(-\color{blue}{\left(2 + \beta\right)}\right) - \beta}{\alpha} \]
      6. distribute-neg-in99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(\left(-2\right) + \left(-\beta\right)\right)} - \beta}{\alpha} \]
      7. metadata-eval99.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{-2} + \left(-\beta\right)\right) - \beta}{\alpha} \]
      8. unsub-neg99.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-2 - \beta\right)} - \beta}{\alpha} \]
    7. Simplified99.4%

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

    if -0.999999900000000053 < (/.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. Step-by-step derivation
      1. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub099.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg99.8%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg99.8%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative99.8%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub99.8%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg99.8%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval99.8%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-199.8%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative99.8%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/99.8%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} \leq -0.9999999:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \mathbf{else}:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 72.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 + \alpha \cdot -0.25\\ \mathbf{if}\;\alpha \leq -5.2 \cdot 10^{-204}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;\alpha \leq -3 \cdot 10^{-258}:\\ \;\;\;\;1\\ \mathbf{elif}\;\alpha \leq 2:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (+ 0.5 (* alpha -0.25))))
   (if (<= alpha -5.2e-204)
     t_0
     (if (<= alpha -3e-258)
       1.0
       (if (<= alpha 2.0) t_0 (* -0.5 (/ (- (- -2.0 beta) beta) alpha)))))))
double code(double alpha, double beta) {
	double t_0 = 0.5 + (alpha * -0.25);
	double tmp;
	if (alpha <= -5.2e-204) {
		tmp = t_0;
	} else if (alpha <= -3e-258) {
		tmp = 1.0;
	} else if (alpha <= 2.0) {
		tmp = t_0;
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	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 = 0.5d0 + (alpha * (-0.25d0))
    if (alpha <= (-5.2d-204)) then
        tmp = t_0
    else if (alpha <= (-3d-258)) then
        tmp = 1.0d0
    else if (alpha <= 2.0d0) then
        tmp = t_0
    else
        tmp = (-0.5d0) * ((((-2.0d0) - beta) - beta) / alpha)
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double t_0 = 0.5 + (alpha * -0.25);
	double tmp;
	if (alpha <= -5.2e-204) {
		tmp = t_0;
	} else if (alpha <= -3e-258) {
		tmp = 1.0;
	} else if (alpha <= 2.0) {
		tmp = t_0;
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	return tmp;
}
def code(alpha, beta):
	t_0 = 0.5 + (alpha * -0.25)
	tmp = 0
	if alpha <= -5.2e-204:
		tmp = t_0
	elif alpha <= -3e-258:
		tmp = 1.0
	elif alpha <= 2.0:
		tmp = t_0
	else:
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha)
	return tmp
function code(alpha, beta)
	t_0 = Float64(0.5 + Float64(alpha * -0.25))
	tmp = 0.0
	if (alpha <= -5.2e-204)
		tmp = t_0;
	elseif (alpha <= -3e-258)
		tmp = 1.0;
	elseif (alpha <= 2.0)
		tmp = t_0;
	else
		tmp = Float64(-0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) / alpha));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	t_0 = 0.5 + (alpha * -0.25);
	tmp = 0.0;
	if (alpha <= -5.2e-204)
		tmp = t_0;
	elseif (alpha <= -3e-258)
		tmp = 1.0;
	elseif (alpha <= 2.0)
		tmp = t_0;
	else
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := Block[{t$95$0 = N[(0.5 + N[(alpha * -0.25), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[alpha, -5.2e-204], t$95$0, If[LessEqual[alpha, -3e-258], 1.0, If[LessEqual[alpha, 2.0], t$95$0, N[(-0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 + \alpha \cdot -0.25\\
\mathbf{if}\;\alpha \leq -5.2 \cdot 10^{-204}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;\alpha \leq -3 \cdot 10^{-258}:\\
\;\;\;\;1\\

\mathbf{elif}\;\alpha \leq 2:\\
\;\;\;\;t\_0\\

\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if alpha < -5.19999999999999965e-204 or -3.00000000000000021e-258 < alpha < 2

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub0100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative100.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg100.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval100.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-1100.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative100.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around 0 98.9%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \color{blue}{\frac{-0.5}{2 + \beta}} \]
    6. Step-by-step derivation
      1. +-commutative98.9%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\beta + 2}} \]
    7. Simplified98.9%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \color{blue}{\frac{-0.5}{\beta + 2}} \]
    8. Taylor expanded in beta around 0 72.3%

      \[\leadsto 0.5 + \color{blue}{-0.25 \cdot \alpha} \]
    9. Step-by-step derivation
      1. *-commutative72.3%

        \[\leadsto 0.5 + \color{blue}{\alpha \cdot -0.25} \]
    10. Simplified72.3%

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

    if -5.19999999999999965e-204 < alpha < -3.00000000000000021e-258

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub0100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative100.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg100.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval100.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-1100.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative100.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in beta around inf 74.6%

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

    if 2 < alpha

    1. Initial program 19.6%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative19.6%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg19.6%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative19.6%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub019.6%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-19.6%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg19.6%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg19.6%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative19.6%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg19.6%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub19.6%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg19.6%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval19.6%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-119.6%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative19.6%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative19.6%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/19.6%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/19.6%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified19.8%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around inf 86.6%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{-1 \cdot \beta - \left(2 + \beta\right)}{\alpha}} \]
    6. Step-by-step derivation
      1. associate--r+86.6%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta - 2\right) - \beta}}{\alpha} \]
      2. sub-neg86.6%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta + \left(-2\right)\right)} - \beta}{\alpha} \]
      3. neg-mul-186.6%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{\left(-\beta\right)} + \left(-2\right)\right) - \beta}{\alpha} \]
      4. distribute-neg-in86.6%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-\left(\beta + 2\right)\right)} - \beta}{\alpha} \]
      5. +-commutative86.6%

        \[\leadsto -0.5 \cdot \frac{\left(-\color{blue}{\left(2 + \beta\right)}\right) - \beta}{\alpha} \]
      6. distribute-neg-in86.6%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(\left(-2\right) + \left(-\beta\right)\right)} - \beta}{\alpha} \]
      7. metadata-eval86.6%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{-2} + \left(-\beta\right)\right) - \beta}{\alpha} \]
      8. unsub-neg86.6%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-2 - \beta\right)} - \beta}{\alpha} \]
    7. Simplified86.6%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification78.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \leq -5.2 \cdot 10^{-204}:\\ \;\;\;\;0.5 + \alpha \cdot -0.25\\ \mathbf{elif}\;\alpha \leq -3 \cdot 10^{-258}:\\ \;\;\;\;1\\ \mathbf{elif}\;\alpha \leq 2:\\ \;\;\;\;0.5 + \alpha \cdot -0.25\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 67.4% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 + \alpha \cdot -0.25\\ \mathbf{if}\;\alpha \leq -5 \cdot 10^{-203}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;\alpha \leq -5 \cdot 10^{-258}:\\ \;\;\;\;1\\ \mathbf{elif}\;\alpha \leq 0.88:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{\alpha}}{2}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (let* ((t_0 (+ 0.5 (* alpha -0.25))))
   (if (<= alpha -5e-203)
     t_0
     (if (<= alpha -5e-258)
       1.0
       (if (<= alpha 0.88) t_0 (/ (/ 2.0 alpha) 2.0))))))
double code(double alpha, double beta) {
	double t_0 = 0.5 + (alpha * -0.25);
	double tmp;
	if (alpha <= -5e-203) {
		tmp = t_0;
	} else if (alpha <= -5e-258) {
		tmp = 1.0;
	} else if (alpha <= 0.88) {
		tmp = t_0;
	} else {
		tmp = (2.0 / alpha) / 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 = 0.5d0 + (alpha * (-0.25d0))
    if (alpha <= (-5d-203)) then
        tmp = t_0
    else if (alpha <= (-5d-258)) then
        tmp = 1.0d0
    else if (alpha <= 0.88d0) then
        tmp = t_0
    else
        tmp = (2.0d0 / alpha) / 2.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double t_0 = 0.5 + (alpha * -0.25);
	double tmp;
	if (alpha <= -5e-203) {
		tmp = t_0;
	} else if (alpha <= -5e-258) {
		tmp = 1.0;
	} else if (alpha <= 0.88) {
		tmp = t_0;
	} else {
		tmp = (2.0 / alpha) / 2.0;
	}
	return tmp;
}
def code(alpha, beta):
	t_0 = 0.5 + (alpha * -0.25)
	tmp = 0
	if alpha <= -5e-203:
		tmp = t_0
	elif alpha <= -5e-258:
		tmp = 1.0
	elif alpha <= 0.88:
		tmp = t_0
	else:
		tmp = (2.0 / alpha) / 2.0
	return tmp
function code(alpha, beta)
	t_0 = Float64(0.5 + Float64(alpha * -0.25))
	tmp = 0.0
	if (alpha <= -5e-203)
		tmp = t_0;
	elseif (alpha <= -5e-258)
		tmp = 1.0;
	elseif (alpha <= 0.88)
		tmp = t_0;
	else
		tmp = Float64(Float64(2.0 / alpha) / 2.0);
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	t_0 = 0.5 + (alpha * -0.25);
	tmp = 0.0;
	if (alpha <= -5e-203)
		tmp = t_0;
	elseif (alpha <= -5e-258)
		tmp = 1.0;
	elseif (alpha <= 0.88)
		tmp = t_0;
	else
		tmp = (2.0 / alpha) / 2.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := Block[{t$95$0 = N[(0.5 + N[(alpha * -0.25), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[alpha, -5e-203], t$95$0, If[LessEqual[alpha, -5e-258], 1.0, If[LessEqual[alpha, 0.88], t$95$0, N[(N[(2.0 / alpha), $MachinePrecision] / 2.0), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 + \alpha \cdot -0.25\\
\mathbf{if}\;\alpha \leq -5 \cdot 10^{-203}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;\alpha \leq -5 \cdot 10^{-258}:\\
\;\;\;\;1\\

\mathbf{elif}\;\alpha \leq 0.88:\\
\;\;\;\;t\_0\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{2}{\alpha}}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if alpha < -5.0000000000000002e-203 or -4.9999999999999999e-258 < alpha < 0.880000000000000004

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub0100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative100.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg100.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval100.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-1100.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative100.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around 0 98.9%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \color{blue}{\frac{-0.5}{2 + \beta}} \]
    6. Step-by-step derivation
      1. +-commutative98.9%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\beta + 2}} \]
    7. Simplified98.9%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \color{blue}{\frac{-0.5}{\beta + 2}} \]
    8. Taylor expanded in beta around 0 72.3%

      \[\leadsto 0.5 + \color{blue}{-0.25 \cdot \alpha} \]
    9. Step-by-step derivation
      1. *-commutative72.3%

        \[\leadsto 0.5 + \color{blue}{\alpha \cdot -0.25} \]
    10. Simplified72.3%

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

    if -5.0000000000000002e-203 < alpha < -4.9999999999999999e-258

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub0100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative100.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg100.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval100.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-1100.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative100.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in beta around inf 74.6%

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

    if 0.880000000000000004 < alpha

    1. Initial program 19.6%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative19.6%

        \[\leadsto \frac{\frac{\beta - \alpha}{\color{blue}{\left(\beta + \alpha\right)} + 2} + 1}{2} \]
    3. Simplified19.6%

      \[\leadsto \color{blue}{\frac{\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1}{2}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u19.4%

        \[\leadsto \frac{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1\right)\right)}}{2} \]
      2. expm1-undefine19.4%

        \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1\right)} - 1}}{2} \]
      3. associate-+r+19.4%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\beta + \left(\alpha + 2\right)}} + 1\right)} - 1}{2} \]
      4. +-commutative19.4%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\left(\alpha + 2\right) + \beta}} + 1\right)} - 1}{2} \]
      5. associate-+l+19.4%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\alpha + \left(2 + \beta\right)}} + 1\right)} - 1}{2} \]
    6. Applied egg-rr19.4%

      \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)} - 1}}{2} \]
    7. Step-by-step derivation
      1. sub-neg19.4%

        \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)} + \left(-1\right)}}{2} \]
      2. log1p-undefine19.5%

        \[\leadsto \frac{e^{\color{blue}{\log \left(1 + \left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)\right)}} + \left(-1\right)}{2} \]
      3. rem-exp-log19.7%

        \[\leadsto \frac{\color{blue}{\left(1 + \left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)\right)} + \left(-1\right)}{2} \]
      4. +-commutative19.7%

        \[\leadsto \frac{\left(1 + \color{blue}{\left(1 + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right)}\right) + \left(-1\right)}{2} \]
      5. associate-+r+19.7%

        \[\leadsto \frac{\color{blue}{\left(\left(1 + 1\right) + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right)} + \left(-1\right)}{2} \]
      6. metadata-eval19.7%

        \[\leadsto \frac{\left(\color{blue}{2} + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right) + \left(-1\right)}{2} \]
      7. +-commutative19.7%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\left(2 + \beta\right) + \alpha}}\right) + \left(-1\right)}{2} \]
      8. +-commutative19.7%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\left(\beta + 2\right)} + \alpha}\right) + \left(-1\right)}{2} \]
      9. associate-+r+19.7%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\beta + \left(2 + \alpha\right)}}\right) + \left(-1\right)}{2} \]
      10. metadata-eval19.7%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + \color{blue}{-1}}{2} \]
    8. Simplified19.7%

      \[\leadsto \frac{\color{blue}{\left(2 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + -1}}{2} \]
    9. Taylor expanded in beta around 0 6.2%

      \[\leadsto \frac{\color{blue}{1 - \frac{\alpha}{2 + \alpha}}}{2} \]
    10. Step-by-step derivation
      1. +-commutative6.2%

        \[\leadsto \frac{1 - \frac{\alpha}{\color{blue}{\alpha + 2}}}{2} \]
    11. Simplified6.2%

      \[\leadsto \frac{\color{blue}{1 - \frac{\alpha}{\alpha + 2}}}{2} \]
    12. Taylor expanded in alpha around inf 65.0%

      \[\leadsto \frac{\color{blue}{\frac{2}{\alpha}}}{2} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification69.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \leq -5 \cdot 10^{-203}:\\ \;\;\;\;0.5 + \alpha \cdot -0.25\\ \mathbf{elif}\;\alpha \leq -5 \cdot 10^{-258}:\\ \;\;\;\;1\\ \mathbf{elif}\;\alpha \leq 0.88:\\ \;\;\;\;0.5 + \alpha \cdot -0.25\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{\alpha}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 93.4% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\alpha \leq 1200000000:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + 2}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= alpha 1200000000.0)
   (+ 0.5 (* (- alpha beta) (/ -0.5 (+ beta 2.0))))
   (* -0.5 (/ (- (- -2.0 beta) beta) alpha))))
double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 1200000000.0) {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + 2.0)));
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (alpha <= 1200000000.0d0) then
        tmp = 0.5d0 + ((alpha - beta) * ((-0.5d0) / (beta + 2.0d0)))
    else
        tmp = (-0.5d0) * ((((-2.0d0) - beta) - beta) / alpha)
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 1200000000.0) {
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + 2.0)));
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if alpha <= 1200000000.0:
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + 2.0)))
	else:
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha)
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (alpha <= 1200000000.0)
		tmp = Float64(0.5 + Float64(Float64(alpha - beta) * Float64(-0.5 / Float64(beta + 2.0))));
	else
		tmp = Float64(-0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) / alpha));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (alpha <= 1200000000.0)
		tmp = 0.5 + ((alpha - beta) * (-0.5 / (beta + 2.0)));
	else
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[alpha, 1200000000.0], N[(0.5 + N[(N[(alpha - beta), $MachinePrecision] * N[(-0.5 / N[(beta + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(-0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\alpha \leq 1200000000:\\
\;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + 2}\\

\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if alpha < 1.2e9

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub0100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg100.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative100.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg100.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval100.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-1100.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative100.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/100.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around 0 99.0%

      \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \color{blue}{\frac{-0.5}{2 + \beta}} \]
    6. Step-by-step derivation
      1. +-commutative99.0%

        \[\leadsto 0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\color{blue}{\beta + 2}} \]
    7. Simplified99.0%

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

    if 1.2e9 < alpha

    1. Initial program 18.9%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative18.9%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub018.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg18.9%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative18.9%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg18.9%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub18.9%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg18.9%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval18.9%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-118.9%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative18.9%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified19.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around inf 87.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{-1 \cdot \beta - \left(2 + \beta\right)}{\alpha}} \]
    6. Step-by-step derivation
      1. associate--r+87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta - 2\right) - \beta}}{\alpha} \]
      2. sub-neg87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta + \left(-2\right)\right)} - \beta}{\alpha} \]
      3. neg-mul-187.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{\left(-\beta\right)} + \left(-2\right)\right) - \beta}{\alpha} \]
      4. distribute-neg-in87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-\left(\beta + 2\right)\right)} - \beta}{\alpha} \]
      5. +-commutative87.4%

        \[\leadsto -0.5 \cdot \frac{\left(-\color{blue}{\left(2 + \beta\right)}\right) - \beta}{\alpha} \]
      6. distribute-neg-in87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(\left(-2\right) + \left(-\beta\right)\right)} - \beta}{\alpha} \]
      7. metadata-eval87.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{-2} + \left(-\beta\right)\right) - \beta}{\alpha} \]
      8. unsub-neg87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-2 - \beta\right)} - \beta}{\alpha} \]
    7. Simplified87.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification94.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \leq 1200000000:\\ \;\;\;\;0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + 2}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 93.0% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\alpha \leq 900000000:\\ \;\;\;\;\frac{\frac{\beta}{\beta + 2} + 1}{2}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \end{array} \]
(FPCore (alpha beta)
 :precision binary64
 (if (<= alpha 900000000.0)
   (/ (+ (/ beta (+ beta 2.0)) 1.0) 2.0)
   (* -0.5 (/ (- (- -2.0 beta) beta) alpha))))
double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 900000000.0) {
		tmp = ((beta / (beta + 2.0)) + 1.0) / 2.0;
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (alpha <= 900000000.0d0) then
        tmp = ((beta / (beta + 2.0d0)) + 1.0d0) / 2.0d0
    else
        tmp = (-0.5d0) * ((((-2.0d0) - beta) - beta) / alpha)
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (alpha <= 900000000.0) {
		tmp = ((beta / (beta + 2.0)) + 1.0) / 2.0;
	} else {
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if alpha <= 900000000.0:
		tmp = ((beta / (beta + 2.0)) + 1.0) / 2.0
	else:
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha)
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (alpha <= 900000000.0)
		tmp = Float64(Float64(Float64(beta / Float64(beta + 2.0)) + 1.0) / 2.0);
	else
		tmp = Float64(-0.5 * Float64(Float64(Float64(-2.0 - beta) - beta) / alpha));
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (alpha <= 900000000.0)
		tmp = ((beta / (beta + 2.0)) + 1.0) / 2.0;
	else
		tmp = -0.5 * (((-2.0 - beta) - beta) / alpha);
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[alpha, 900000000.0], N[(N[(N[(beta / N[(beta + 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] / 2.0), $MachinePrecision], N[(-0.5 * N[(N[(N[(-2.0 - beta), $MachinePrecision] - beta), $MachinePrecision] / alpha), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\alpha \leq 900000000:\\
\;\;\;\;\frac{\frac{\beta}{\beta + 2} + 1}{2}\\

\mathbf{else}:\\
\;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if alpha < 9e8

    1. Initial program 100.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\frac{\beta - \alpha}{\color{blue}{\left(\beta + \alpha\right)} + 2} + 1}{2} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1}{2}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around 0 98.4%

      \[\leadsto \frac{\color{blue}{1 + \frac{\beta}{2 + \beta}}}{2} \]
    6. Step-by-step derivation
      1. +-commutative98.4%

        \[\leadsto \frac{\color{blue}{\frac{\beta}{2 + \beta} + 1}}{2} \]
      2. +-commutative98.4%

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

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

    if 9e8 < alpha

    1. Initial program 18.9%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative18.9%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub018.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg18.9%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg18.9%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative18.9%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg18.9%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub18.9%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg18.9%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval18.9%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-118.9%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative18.9%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/18.9%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified19.0%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in alpha around inf 87.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{-1 \cdot \beta - \left(2 + \beta\right)}{\alpha}} \]
    6. Step-by-step derivation
      1. associate--r+87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta - 2\right) - \beta}}{\alpha} \]
      2. sub-neg87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-1 \cdot \beta + \left(-2\right)\right)} - \beta}{\alpha} \]
      3. neg-mul-187.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{\left(-\beta\right)} + \left(-2\right)\right) - \beta}{\alpha} \]
      4. distribute-neg-in87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-\left(\beta + 2\right)\right)} - \beta}{\alpha} \]
      5. +-commutative87.4%

        \[\leadsto -0.5 \cdot \frac{\left(-\color{blue}{\left(2 + \beta\right)}\right) - \beta}{\alpha} \]
      6. distribute-neg-in87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(\left(-2\right) + \left(-\beta\right)\right)} - \beta}{\alpha} \]
      7. metadata-eval87.4%

        \[\leadsto -0.5 \cdot \frac{\left(\color{blue}{-2} + \left(-\beta\right)\right) - \beta}{\alpha} \]
      8. unsub-neg87.4%

        \[\leadsto -0.5 \cdot \frac{\color{blue}{\left(-2 - \beta\right)} - \beta}{\alpha} \]
    7. Simplified87.4%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification94.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \leq 900000000:\\ \;\;\;\;\frac{\frac{\beta}{\beta + 2} + 1}{2}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{\left(-2 - \beta\right) - \beta}{\alpha}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 71.7% accurate, 2.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\beta \leq 225:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (alpha beta) :precision binary64 (if (<= beta 225.0) 0.5 1.0))
double code(double alpha, double beta) {
	double tmp;
	if (beta <= 225.0) {
		tmp = 0.5;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    real(8) :: tmp
    if (beta <= 225.0d0) then
        tmp = 0.5d0
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double alpha, double beta) {
	double tmp;
	if (beta <= 225.0) {
		tmp = 0.5;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(alpha, beta):
	tmp = 0
	if beta <= 225.0:
		tmp = 0.5
	else:
		tmp = 1.0
	return tmp
function code(alpha, beta)
	tmp = 0.0
	if (beta <= 225.0)
		tmp = 0.5;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(alpha, beta)
	tmp = 0.0;
	if (beta <= 225.0)
		tmp = 0.5;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[alpha_, beta_] := If[LessEqual[beta, 225.0], 0.5, 1.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\beta \leq 225:\\
\;\;\;\;0.5\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if beta < 225

    1. Initial program 62.2%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative62.2%

        \[\leadsto \frac{\frac{\beta - \alpha}{\color{blue}{\left(\beta + \alpha\right)} + 2} + 1}{2} \]
    3. Simplified62.2%

      \[\leadsto \color{blue}{\frac{\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1}{2}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u62.2%

        \[\leadsto \frac{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1\right)\right)}}{2} \]
      2. expm1-undefine62.2%

        \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\left(\beta + \alpha\right) + 2} + 1\right)} - 1}}{2} \]
      3. associate-+r+62.2%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\beta + \left(\alpha + 2\right)}} + 1\right)} - 1}{2} \]
      4. +-commutative62.2%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\left(\alpha + 2\right) + \beta}} + 1\right)} - 1}{2} \]
      5. associate-+l+62.2%

        \[\leadsto \frac{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\color{blue}{\alpha + \left(2 + \beta\right)}} + 1\right)} - 1}{2} \]
    6. Applied egg-rr62.2%

      \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)} - 1}}{2} \]
    7. Step-by-step derivation
      1. sub-neg62.2%

        \[\leadsto \frac{\color{blue}{e^{\mathsf{log1p}\left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)} + \left(-1\right)}}{2} \]
      2. log1p-undefine62.2%

        \[\leadsto \frac{e^{\color{blue}{\log \left(1 + \left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)\right)}} + \left(-1\right)}{2} \]
      3. rem-exp-log62.2%

        \[\leadsto \frac{\color{blue}{\left(1 + \left(\frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)} + 1\right)\right)} + \left(-1\right)}{2} \]
      4. +-commutative62.2%

        \[\leadsto \frac{\left(1 + \color{blue}{\left(1 + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right)}\right) + \left(-1\right)}{2} \]
      5. associate-+r+62.2%

        \[\leadsto \frac{\color{blue}{\left(\left(1 + 1\right) + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right)} + \left(-1\right)}{2} \]
      6. metadata-eval62.2%

        \[\leadsto \frac{\left(\color{blue}{2} + \frac{\beta - \alpha}{\alpha + \left(2 + \beta\right)}\right) + \left(-1\right)}{2} \]
      7. +-commutative62.2%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\left(2 + \beta\right) + \alpha}}\right) + \left(-1\right)}{2} \]
      8. +-commutative62.2%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\left(\beta + 2\right)} + \alpha}\right) + \left(-1\right)}{2} \]
      9. associate-+r+62.2%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\color{blue}{\beta + \left(2 + \alpha\right)}}\right) + \left(-1\right)}{2} \]
      10. metadata-eval62.2%

        \[\leadsto \frac{\left(2 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + \color{blue}{-1}}{2} \]
    8. Simplified62.2%

      \[\leadsto \frac{\color{blue}{\left(2 + \frac{\beta - \alpha}{\beta + \left(2 + \alpha\right)}\right) + -1}}{2} \]
    9. Taylor expanded in beta around 0 61.0%

      \[\leadsto \frac{\color{blue}{1 - \frac{\alpha}{2 + \alpha}}}{2} \]
    10. Step-by-step derivation
      1. +-commutative61.0%

        \[\leadsto \frac{1 - \frac{\alpha}{\color{blue}{\alpha + 2}}}{2} \]
    11. Simplified61.0%

      \[\leadsto \frac{\color{blue}{1 - \frac{\alpha}{\alpha + 2}}}{2} \]
    12. Taylor expanded in alpha around 0 58.7%

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

    if 225 < beta

    1. Initial program 77.0%

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
    2. Step-by-step derivation
      1. +-commutative77.0%

        \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
      2. sub-neg77.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      3. +-commutative77.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
      4. neg-sub077.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
      5. associate-+l-77.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      6. sub0-neg77.0%

        \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
      7. distribute-frac-neg77.0%

        \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
      8. +-commutative77.0%

        \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
      9. sub-neg77.0%

        \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
      10. div-sub77.0%

        \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      11. sub-neg77.0%

        \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
      12. metadata-eval77.0%

        \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
      13. neg-mul-177.0%

        \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
      14. *-commutative77.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
      15. +-commutative77.0%

        \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
      16. associate-/l/77.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
      17. associate-*l/77.0%

        \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
    3. Simplified77.2%

      \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
    4. Add Preprocessing
    5. Taylor expanded in beta around inf 74.5%

      \[\leadsto \color{blue}{1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\beta \leq 225:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 37.7% accurate, 13.0× speedup?

\[\begin{array}{l} \\ 1 \end{array} \]
(FPCore (alpha beta) :precision binary64 1.0)
double code(double alpha, double beta) {
	return 1.0;
}
real(8) function code(alpha, beta)
    real(8), intent (in) :: alpha
    real(8), intent (in) :: beta
    code = 1.0d0
end function
public static double code(double alpha, double beta) {
	return 1.0;
}
def code(alpha, beta):
	return 1.0
function code(alpha, beta)
	return 1.0
end
function tmp = code(alpha, beta)
	tmp = 1.0;
end
code[alpha_, beta_] := 1.0
\begin{array}{l}

\\
1
\end{array}
Derivation
  1. Initial program 67.3%

    \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2} \]
  2. Step-by-step derivation
    1. +-commutative67.3%

      \[\leadsto \frac{\color{blue}{1 + \frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2}}}{2} \]
    2. sub-neg67.3%

      \[\leadsto \frac{1 + \frac{\color{blue}{\beta + \left(-\alpha\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
    3. +-commutative67.3%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(-\alpha\right) + \beta}}{\left(\alpha + \beta\right) + 2}}{2} \]
    4. neg-sub067.3%

      \[\leadsto \frac{1 + \frac{\color{blue}{\left(0 - \alpha\right)} + \beta}{\left(\alpha + \beta\right) + 2}}{2} \]
    5. associate-+l-67.3%

      \[\leadsto \frac{1 + \frac{\color{blue}{0 - \left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
    6. sub0-neg67.3%

      \[\leadsto \frac{1 + \frac{\color{blue}{-\left(\alpha - \beta\right)}}{\left(\alpha + \beta\right) + 2}}{2} \]
    7. distribute-frac-neg67.3%

      \[\leadsto \frac{1 + \color{blue}{\left(-\frac{\alpha - \beta}{\left(\alpha + \beta\right) + 2}\right)}}{2} \]
    8. +-commutative67.3%

      \[\leadsto \frac{1 + \left(-\frac{\alpha - \beta}{\color{blue}{\left(\beta + \alpha\right)} + 2}\right)}{2} \]
    9. sub-neg67.3%

      \[\leadsto \frac{\color{blue}{1 - \frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}}{2} \]
    10. div-sub67.3%

      \[\leadsto \color{blue}{\frac{1}{2} - \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
    11. sub-neg67.3%

      \[\leadsto \color{blue}{\frac{1}{2} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right)} \]
    12. metadata-eval67.3%

      \[\leadsto \color{blue}{0.5} + \left(-\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}\right) \]
    13. neg-mul-167.3%

      \[\leadsto 0.5 + \color{blue}{-1 \cdot \frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2}} \]
    14. *-commutative67.3%

      \[\leadsto 0.5 + \color{blue}{\frac{\frac{\alpha - \beta}{\left(\beta + \alpha\right) + 2}}{2} \cdot -1} \]
    15. +-commutative67.3%

      \[\leadsto 0.5 + \frac{\frac{\alpha - \beta}{\color{blue}{\left(\alpha + \beta\right)} + 2}}{2} \cdot -1 \]
    16. associate-/l/67.3%

      \[\leadsto 0.5 + \color{blue}{\frac{\alpha - \beta}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \cdot -1 \]
    17. associate-*l/67.3%

      \[\leadsto 0.5 + \color{blue}{\frac{\left(\alpha - \beta\right) \cdot -1}{2 \cdot \left(\left(\alpha + \beta\right) + 2\right)}} \]
  3. Simplified67.4%

    \[\leadsto \color{blue}{0.5 + \left(\alpha - \beta\right) \cdot \frac{-0.5}{\beta + \left(\alpha + 2\right)}} \]
  4. Add Preprocessing
  5. Taylor expanded in beta around inf 34.5%

    \[\leadsto \color{blue}{1} \]
  6. Final simplification34.5%

    \[\leadsto 1 \]
  7. Add Preprocessing

Reproduce

?
herbie shell --seed 2024079 
(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))