Average Error: 16.4 → 6.8
Time: 22.1s
Precision: 64
\[\alpha \gt -1 \land \beta \gt -1\]
\[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}\]
\[\begin{array}{l} \mathbf{if}\;\alpha \le 5062494549189153:\\ \;\;\;\;e^{\left(-\log \left(\sqrt{2}\right)\right) + \log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\sqrt{2}}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{4}{\alpha \cdot \alpha} - \left(\frac{2}{\alpha} + \frac{8}{{\alpha}^{3}}\right)\right)}{2}\\ \end{array}\]
\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}
\begin{array}{l}
\mathbf{if}\;\alpha \le 5062494549189153:\\
\;\;\;\;e^{\left(-\log \left(\sqrt{2}\right)\right) + \log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\sqrt{2}}\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{4}{\alpha \cdot \alpha} - \left(\frac{2}{\alpha} + \frac{8}{{\alpha}^{3}}\right)\right)}{2}\\

\end{array}
double f(double alpha, double beta) {
        double r67731 = beta;
        double r67732 = alpha;
        double r67733 = r67731 - r67732;
        double r67734 = r67732 + r67731;
        double r67735 = 2.0;
        double r67736 = r67734 + r67735;
        double r67737 = r67733 / r67736;
        double r67738 = 1.0;
        double r67739 = r67737 + r67738;
        double r67740 = r67739 / r67735;
        return r67740;
}

double f(double alpha, double beta) {
        double r67741 = alpha;
        double r67742 = 5062494549189153.0;
        bool r67743 = r67741 <= r67742;
        double r67744 = 2.0;
        double r67745 = sqrt(r67744);
        double r67746 = log(r67745);
        double r67747 = -r67746;
        double r67748 = beta;
        double r67749 = r67741 + r67748;
        double r67750 = r67749 + r67744;
        double r67751 = r67748 / r67750;
        double r67752 = r67741 / r67750;
        double r67753 = 1.0;
        double r67754 = r67752 - r67753;
        double r67755 = r67751 - r67754;
        double r67756 = r67755 / r67745;
        double r67757 = log(r67756);
        double r67758 = r67747 + r67757;
        double r67759 = exp(r67758);
        double r67760 = 4.0;
        double r67761 = r67741 * r67741;
        double r67762 = r67760 / r67761;
        double r67763 = r67744 / r67741;
        double r67764 = 8.0;
        double r67765 = 3.0;
        double r67766 = pow(r67741, r67765);
        double r67767 = r67764 / r67766;
        double r67768 = r67763 + r67767;
        double r67769 = r67762 - r67768;
        double r67770 = r67751 - r67769;
        double r67771 = r67770 / r67744;
        double r67772 = r67743 ? r67759 : r67771;
        return r67772;
}

Error

Bits error versus alpha

Bits error versus beta

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if alpha < 5062494549189153.0

    1. Initial program 0.4

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}\]
    2. Using strategy rm
    3. Applied div-sub0.4

      \[\leadsto \frac{\color{blue}{\left(\frac{\beta}{\left(\alpha + \beta\right) + 2} - \frac{\alpha}{\left(\alpha + \beta\right) + 2}\right)} + 1}{2}\]
    4. Applied associate-+l-0.4

      \[\leadsto \frac{\color{blue}{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}}{2}\]
    5. Using strategy rm
    6. Applied add-exp-log0.4

      \[\leadsto \frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\color{blue}{e^{\log 2}}}\]
    7. Applied add-exp-log0.4

      \[\leadsto \frac{\color{blue}{e^{\log \left(\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)\right)}}}{e^{\log 2}}\]
    8. Applied div-exp0.4

      \[\leadsto \color{blue}{e^{\log \left(\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)\right) - \log 2}}\]
    9. Simplified0.4

      \[\leadsto e^{\color{blue}{\log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{2}\right)}}\]
    10. Using strategy rm
    11. Applied add-sqr-sqrt1.9

      \[\leadsto e^{\log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\color{blue}{\sqrt{2} \cdot \sqrt{2}}}\right)}\]
    12. Applied *-un-lft-identity1.9

      \[\leadsto e^{\log \left(\frac{\color{blue}{1 \cdot \left(\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)\right)}}{\sqrt{2} \cdot \sqrt{2}}\right)}\]
    13. Applied times-frac1.9

      \[\leadsto e^{\log \color{blue}{\left(\frac{1}{\sqrt{2}} \cdot \frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\sqrt{2}}\right)}}\]
    14. Applied log-prod1.7

      \[\leadsto e^{\color{blue}{\log \left(\frac{1}{\sqrt{2}}\right) + \log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\sqrt{2}}\right)}}\]
    15. Simplified1.4

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

    if 5062494549189153.0 < alpha

    1. Initial program 50.4

      \[\frac{\frac{\beta - \alpha}{\left(\alpha + \beta\right) + 2} + 1}{2}\]
    2. Using strategy rm
    3. Applied div-sub50.4

      \[\leadsto \frac{\color{blue}{\left(\frac{\beta}{\left(\alpha + \beta\right) + 2} - \frac{\alpha}{\left(\alpha + \beta\right) + 2}\right)} + 1}{2}\]
    4. Applied associate-+l-48.7

      \[\leadsto \frac{\color{blue}{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}}{2}\]
    5. Taylor expanded around inf 18.4

      \[\leadsto \frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \color{blue}{\left(4 \cdot \frac{1}{{\alpha}^{2}} - \left(2 \cdot \frac{1}{\alpha} + 8 \cdot \frac{1}{{\alpha}^{3}}\right)\right)}}{2}\]
    6. Simplified18.4

      \[\leadsto \frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \color{blue}{\left(\frac{4}{\alpha \cdot \alpha} - \left(\frac{2}{\alpha} + \frac{8}{{\alpha}^{3}}\right)\right)}}{2}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification6.8

    \[\leadsto \begin{array}{l} \mathbf{if}\;\alpha \le 5062494549189153:\\ \;\;\;\;e^{\left(-\log \left(\sqrt{2}\right)\right) + \log \left(\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{\alpha}{\left(\alpha + \beta\right) + 2} - 1\right)}{\sqrt{2}}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\beta}{\left(\alpha + \beta\right) + 2} - \left(\frac{4}{\alpha \cdot \alpha} - \left(\frac{2}{\alpha} + \frac{8}{{\alpha}^{3}}\right)\right)}{2}\\ \end{array}\]

Reproduce

herbie shell --seed 2019303 +o rules:numerics
(FPCore (alpha beta)
  :name "Octave 3.8, jcobi/1"
  :precision binary64
  :pre (and (> alpha -1) (> beta -1))
  (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2)) 1) 2))