Average Error: 10.6 → 10.3
Time: 12.9s
Precision: 64
Internal Precision: 576
\[\frac{a1 \cdot a2}{b1 \cdot b2}\]
\[\begin{array}{l} \mathbf{if}\;a2 \le -3.744170422286937 \cdot 10^{-227}:\\ \;\;\;\;\frac{a2}{b2} \cdot \frac{a1}{b1}\\ \mathbf{elif}\;a2 \le 9.808602920791376 \cdot 10^{-287}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{elif}\;a2 \le 2.3271170994576882 \cdot 10^{-206}:\\ \;\;\;\;\frac{a2}{b2} \cdot \frac{a1}{b1}\\ \mathbf{else}:\\ \;\;\;\;\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}\\ \end{array}\]

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

Original10.6
Target10.9
Herbie10.3
\[\frac{a1}{b1} \cdot \frac{a2}{b2}\]

Derivation

  1. Split input into 3 regimes
  2. if a2 < -3.744170422286937e-227 or 9.808602920791376e-287 < a2 < 2.3271170994576882e-206

    1. Initial program 10.9

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification11.6

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv11.7

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right)} \cdot \frac{a2}{b1}\]
    5. Applied associate-*l*11.7

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*r*11.7

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}}\]
    8. Using strategy rm
    9. Applied pow111.7

      \[\leadsto \left(a1 \cdot \frac{1}{b2}\right) \cdot \color{blue}{{\left(\frac{a2}{b1}\right)}^{1}}\]
    10. Applied pow111.7

      \[\leadsto \color{blue}{{\left(a1 \cdot \frac{1}{b2}\right)}^{1}} \cdot {\left(\frac{a2}{b1}\right)}^{1}\]
    11. Applied pow-prod-down11.7

      \[\leadsto \color{blue}{{\left(\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}\right)}^{1}}\]
    12. Simplified10.3

      \[\leadsto {\color{blue}{\left(\frac{a1}{b1} \cdot \frac{a2}{b2}\right)}}^{1}\]

    if -3.744170422286937e-227 < a2 < 9.808602920791376e-287

    1. Initial program 9.0

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification11.7

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv11.7

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

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*r*11.7

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}}\]
    8. Using strategy rm
    9. Applied associate-*r/11.7

      \[\leadsto \color{blue}{\frac{a1 \cdot 1}{b2}} \cdot \frac{a2}{b1}\]
    10. Applied frac-times9.0

      \[\leadsto \color{blue}{\frac{\left(a1 \cdot 1\right) \cdot a2}{b2 \cdot b1}}\]
    11. Simplified9.0

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

    if 2.3271170994576882e-206 < a2

    1. Initial program 10.5

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification10.6

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv10.6

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right)} \cdot \frac{a2}{b1}\]
    5. Applied associate-*l*11.0

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*r*10.6

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification10.3

    \[\leadsto \begin{array}{l} \mathbf{if}\;a2 \le -3.744170422286937 \cdot 10^{-227}:\\ \;\;\;\;\frac{a2}{b2} \cdot \frac{a1}{b1}\\ \mathbf{elif}\;a2 \le 9.808602920791376 \cdot 10^{-287}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{elif}\;a2 \le 2.3271170994576882 \cdot 10^{-206}:\\ \;\;\;\;\frac{a2}{b2} \cdot \frac{a1}{b1}\\ \mathbf{else}:\\ \;\;\;\;\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}\\ \end{array}\]

Runtime

Time bar (total: 12.9s)Debug logProfile

BaselineHerbieOracleSpan%
Regimes11.310.30.011.28.6%
herbie shell --seed 2018285 
(FPCore (a1 a2 b1 b2)
  :name "Quotient of products"

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

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