Average Error: 3.5 → 1.2
Time: 5.5m
Precision: 64
Internal Precision: 128
\[\frac{\frac{\frac{\left(\left(\alpha + \beta\right) + \beta \cdot \alpha\right) + 1.0}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\left(\alpha + \beta\right) + 2 \cdot 1\right) + 1.0}\]
\[\begin{array}{l} \mathbf{if}\;\beta \le 8.34052549037273 \cdot 10^{+155}:\\ \;\;\;\;\frac{\frac{\sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{1.0 + \left(2 + \left(\alpha + \beta\right)\right)}} \cdot \sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{1.0 + \left(2 + \left(\alpha + \beta\right)\right)}}}{2 + \left(\alpha + \beta\right)}}{2 + \left(\alpha + \beta\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + \left(\left(\alpha + \beta\right) + 1.0\right)} \cdot \frac{1}{\frac{\beta}{\alpha} + \left(\frac{\alpha}{\beta} + 2\right)}\\ \end{array}\]

Error

Bits error versus alpha

Bits error versus beta

Derivation

  1. Split input into 2 regimes
  2. if beta < 8.34052549037273e+155

    1. Initial program 1.2

      \[\frac{\frac{\frac{\left(\left(\alpha + \beta\right) + \beta \cdot \alpha\right) + 1.0}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\left(\alpha + \beta\right) + 2 \cdot 1\right) + 1.0}\]
    2. Simplified1.2

      \[\leadsto \color{blue}{\frac{\frac{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}}\]
    3. Using strategy rm
    4. Applied *-un-lft-identity1.2

      \[\leadsto \frac{\frac{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{\color{blue}{1 \cdot \left(2 + \left(\beta + \alpha\right)\right)}}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    5. Applied *-un-lft-identity1.2

      \[\leadsto \frac{\frac{\frac{\color{blue}{1 \cdot \left(1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*\right)}}{1 \cdot \left(2 + \left(\beta + \alpha\right)\right)}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    6. Applied times-frac1.2

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{1} \cdot \frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    7. Applied associate-/l*1.2

      \[\leadsto \frac{\color{blue}{\frac{\frac{1}{1}}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    8. Simplified1.2

      \[\leadsto \frac{\frac{\color{blue}{1}}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    9. Using strategy rm
    10. Applied div-inv1.3

      \[\leadsto \color{blue}{\frac{1}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}} \cdot \frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}}\]
    11. Using strategy rm
    12. Applied pow11.3

      \[\leadsto \frac{1}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}} \cdot \color{blue}{{\left(\frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\right)}^{1}}\]
    13. Applied pow11.3

      \[\leadsto \color{blue}{{\left(\frac{1}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}\right)}^{1}} \cdot {\left(\frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\right)}^{1}\]
    14. Applied pow-prod-down1.3

      \[\leadsto \color{blue}{{\left(\frac{1}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}} \cdot \frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\right)}^{1}}\]
    15. Simplified1.2

      \[\leadsto {\color{blue}{\left(\frac{\frac{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{\left(2 + \left(\alpha + \beta\right)\right) + 1.0}}{2 + \left(\alpha + \beta\right)}}{2 + \left(\alpha + \beta\right)}\right)}}^{1}\]
    16. Using strategy rm
    17. Applied add-sqr-sqrt1.3

      \[\leadsto {\left(\frac{\frac{\color{blue}{\sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{\left(2 + \left(\alpha + \beta\right)\right) + 1.0}} \cdot \sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{\left(2 + \left(\alpha + \beta\right)\right) + 1.0}}}}{2 + \left(\alpha + \beta\right)}}{2 + \left(\alpha + \beta\right)}\right)}^{1}\]

    if 8.34052549037273e+155 < beta

    1. Initial program 15.8

      \[\frac{\frac{\frac{\left(\left(\alpha + \beta\right) + \beta \cdot \alpha\right) + 1.0}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\alpha + \beta\right) + 2 \cdot 1}}{\left(\left(\alpha + \beta\right) + 2 \cdot 1\right) + 1.0}\]
    2. Simplified15.8

      \[\leadsto \color{blue}{\frac{\frac{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}}\]
    3. Using strategy rm
    4. Applied *-un-lft-identity15.8

      \[\leadsto \frac{\frac{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{\color{blue}{1 \cdot \left(2 + \left(\beta + \alpha\right)\right)}}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    5. Applied *-un-lft-identity15.8

      \[\leadsto \frac{\frac{\frac{\color{blue}{1 \cdot \left(1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*\right)}}{1 \cdot \left(2 + \left(\beta + \alpha\right)\right)}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    6. Applied times-frac15.8

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{1} \cdot \frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}{2 + \left(\beta + \alpha\right)}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    7. Applied associate-/l*15.8

      \[\leadsto \frac{\color{blue}{\frac{\frac{1}{1}}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    8. Simplified15.8

      \[\leadsto \frac{\frac{\color{blue}{1}}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}}}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
    9. Using strategy rm
    10. Applied div-inv15.8

      \[\leadsto \color{blue}{\frac{1}{\frac{2 + \left(\beta + \alpha\right)}{\frac{1.0 + (\beta \cdot \alpha + \left(\beta + \alpha\right))_*}{2 + \left(\beta + \alpha\right)}}} \cdot \frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}}\]
    11. Taylor expanded around -inf 0.6

      \[\leadsto \frac{1}{\color{blue}{\frac{\beta}{\alpha} + \left(2 + \frac{\alpha}{\beta}\right)}} \cdot \frac{1}{\left(1.0 + \left(\beta + \alpha\right)\right) + 2}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification1.2

    \[\leadsto \begin{array}{l} \mathbf{if}\;\beta \le 8.34052549037273 \cdot 10^{+155}:\\ \;\;\;\;\frac{\frac{\sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{1.0 + \left(2 + \left(\alpha + \beta\right)\right)}} \cdot \sqrt{\frac{(\beta \cdot \alpha + \left(\alpha + \beta\right))_* + 1.0}{1.0 + \left(2 + \left(\alpha + \beta\right)\right)}}}{2 + \left(\alpha + \beta\right)}}{2 + \left(\alpha + \beta\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + \left(\left(\alpha + \beta\right) + 1.0\right)} \cdot \frac{1}{\frac{\beta}{\alpha} + \left(\frac{\alpha}{\beta} + 2\right)}\\ \end{array}\]

Reproduce

herbie shell --seed 2019050 +o rules:numerics
(FPCore (alpha beta)
  :name "Octave 3.8, jcobi/3"
  :pre (and (> alpha -1) (> beta -1))
  (/ (/ (/ (+ (+ (+ alpha beta) (* beta alpha)) 1.0) (+ (+ alpha beta) (* 2 1))) (+ (+ alpha beta) (* 2 1))) (+ (+ (+ alpha beta) (* 2 1)) 1.0)))