Average Error: 10.7 → 6.3
Time: 9.3s
Precision: 64
Internal Precision: 576
\[\frac{a1 \cdot a2}{b1 \cdot b2}\]
\[\begin{array}{l} \mathbf{if}\;b1 \cdot b2 \le -2.06541239684983 \cdot 10^{+256}:\\ \;\;\;\;\frac{\frac{a1 \cdot a2}{b1}}{b2}\\ \mathbf{elif}\;b1 \cdot b2 \le -1.794287396877486 \cdot 10^{-178}:\\ \;\;\;\;\frac{1}{\frac{1}{a2}} \cdot \frac{a1}{b1 \cdot b2}\\ \mathbf{elif}\;b1 \cdot b2 \le 2.200863960063993 \cdot 10^{-305}:\\ \;\;\;\;\frac{a1}{b2} \cdot \frac{a2}{b1}\\ \mathbf{elif}\;b1 \cdot b2 \le 3.641633386252542 \cdot 10^{+119}:\\ \;\;\;\;\frac{\frac{a1}{b1 \cdot b2}}{\frac{1}{a2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{a2}{b2}}{b1} \cdot a1\\ \end{array}\]

Error

Bits error versus a1

Bits error versus a2

Bits error versus b1

Bits error versus b2

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original10.7
Target10.9
Herbie6.3
\[\frac{a1}{b1} \cdot \frac{a2}{b2}\]

Derivation

  1. Split input into 5 regimes
  2. if (* b1 b2) < -2.06541239684983e+256

    1. Initial program 17.7

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Using strategy rm
    3. Applied associate-/r*7.9

      \[\leadsto \color{blue}{\frac{\frac{a1 \cdot a2}{b1}}{b2}}\]

    if -2.06541239684983e+256 < (* b1 b2) < -1.794287396877486e-178

    1. Initial program 4.6

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Using strategy rm
    3. Applied associate-/l*4.5

      \[\leadsto \color{blue}{\frac{a1}{\frac{b1 \cdot b2}{a2}}}\]
    4. Using strategy rm
    5. Applied div-inv4.6

      \[\leadsto \frac{a1}{\color{blue}{\left(b1 \cdot b2\right) \cdot \frac{1}{a2}}}\]
    6. Applied associate-/r*4.6

      \[\leadsto \color{blue}{\frac{\frac{a1}{b1 \cdot b2}}{\frac{1}{a2}}}\]
    7. Using strategy rm
    8. Applied div-inv4.6

      \[\leadsto \color{blue}{\frac{a1}{b1 \cdot b2} \cdot \frac{1}{\frac{1}{a2}}}\]

    if -1.794287396877486e-178 < (* b1 b2) < 2.200863960063993e-305

    1. Initial program 35.8

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification10.0

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]

    if 2.200863960063993e-305 < (* b1 b2) < 3.641633386252542e+119

    1. Initial program 4.6

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Using strategy rm
    3. Applied associate-/l*5.5

      \[\leadsto \color{blue}{\frac{a1}{\frac{b1 \cdot b2}{a2}}}\]
    4. Using strategy rm
    5. Applied div-inv5.6

      \[\leadsto \frac{a1}{\color{blue}{\left(b1 \cdot b2\right) \cdot \frac{1}{a2}}}\]
    6. Applied associate-/r*5.3

      \[\leadsto \color{blue}{\frac{\frac{a1}{b1 \cdot b2}}{\frac{1}{a2}}}\]

    if 3.641633386252542e+119 < (* b1 b2)

    1. Initial program 11.5

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Using strategy rm
    3. Applied associate-/l*12.4

      \[\leadsto \color{blue}{\frac{a1}{\frac{b1 \cdot b2}{a2}}}\]
    4. Using strategy rm
    5. Applied div-inv12.4

      \[\leadsto \frac{a1}{\color{blue}{\left(b1 \cdot b2\right) \cdot \frac{1}{a2}}}\]
    6. Applied associate-/r*12.1

      \[\leadsto \color{blue}{\frac{\frac{a1}{b1 \cdot b2}}{\frac{1}{a2}}}\]
    7. Using strategy rm
    8. Applied *-un-lft-identity12.1

      \[\leadsto \frac{\frac{a1}{b1 \cdot b2}}{\color{blue}{1 \cdot \frac{1}{a2}}}\]
    9. Applied div-inv12.1

      \[\leadsto \frac{\color{blue}{a1 \cdot \frac{1}{b1 \cdot b2}}}{1 \cdot \frac{1}{a2}}\]
    10. Applied times-frac12.0

      \[\leadsto \color{blue}{\frac{a1}{1} \cdot \frac{\frac{1}{b1 \cdot b2}}{\frac{1}{a2}}}\]
    11. Simplified12.0

      \[\leadsto \color{blue}{a1} \cdot \frac{\frac{1}{b1 \cdot b2}}{\frac{1}{a2}}\]
    12. Simplified7.6

      \[\leadsto a1 \cdot \color{blue}{\frac{\frac{a2}{b2}}{b1}}\]
  3. Recombined 5 regimes into one program.
  4. Final simplification6.3

    \[\leadsto \begin{array}{l} \mathbf{if}\;b1 \cdot b2 \le -2.06541239684983 \cdot 10^{+256}:\\ \;\;\;\;\frac{\frac{a1 \cdot a2}{b1}}{b2}\\ \mathbf{elif}\;b1 \cdot b2 \le -1.794287396877486 \cdot 10^{-178}:\\ \;\;\;\;\frac{1}{\frac{1}{a2}} \cdot \frac{a1}{b1 \cdot b2}\\ \mathbf{elif}\;b1 \cdot b2 \le 2.200863960063993 \cdot 10^{-305}:\\ \;\;\;\;\frac{a1}{b2} \cdot \frac{a2}{b1}\\ \mathbf{elif}\;b1 \cdot b2 \le 3.641633386252542 \cdot 10^{+119}:\\ \;\;\;\;\frac{\frac{a1}{b1 \cdot b2}}{\frac{1}{a2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{a2}{b2}}{b1} \cdot a1\\ \end{array}\]

Runtime

Time bar (total: 9.3s)Debug logProfile

BaselineHerbieOracleSpan%
Regimes11.06.30.010.942.6%
herbie shell --seed 2018274 
(FPCore (a1 a2 b1 b2)
  :name "Quotient of products"

  :herbie-target
  (* (/ a1 b1) (/ a2 b2))

  (/ (* a1 a2) (* b1 b2)))