Average Error: 11.1 → 6.0
Time: 10.0s
Precision: 64
Internal Precision: 576
\[\frac{a1 \cdot a2}{b1 \cdot b2}\]
\[\begin{array}{l} \mathbf{if}\;a1 \cdot a2 \le -7.627138752121106 \cdot 10^{+55}:\\ \;\;\;\;a1 \cdot \frac{\frac{a2}{b1}}{b2}\\ \mathbf{elif}\;a1 \cdot a2 \le -5.106090969630976 \cdot 10^{-119}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{elif}\;a1 \cdot a2 \le -0.0:\\ \;\;\;\;\frac{a1}{b1} \cdot \frac{a2}{b2}\\ \mathbf{elif}\;a1 \cdot a2 \le 6.416315954955407 \cdot 10^{+192}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{else}:\\ \;\;\;\;\frac{a1}{b1} \cdot \frac{a2}{b2}\\ \end{array}\]

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

Original11.1
Target10.9
Herbie6.0
\[\frac{a1}{b1} \cdot \frac{a2}{b2}\]

Derivation

  1. Split input into 3 regimes
  2. if (* a1 a2) < -7.627138752121106e+55

    1. Initial program 18.1

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification13.5

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv13.6

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right)} \cdot \frac{a2}{b1}\]
    5. Applied associate-*l*11.9

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*l/11.8

      \[\leadsto a1 \cdot \color{blue}{\frac{1 \cdot \frac{a2}{b1}}{b2}}\]
    8. Simplified11.8

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

    if -7.627138752121106e+55 < (* a1 a2) < -5.106090969630976e-119 or -0.0 < (* a1 a2) < 6.416315954955407e+192

    1. Initial program 4.1

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification13.5

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv13.6

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right)} \cdot \frac{a2}{b1}\]
    5. Applied associate-*l*13.6

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*l/13.5

      \[\leadsto a1 \cdot \color{blue}{\frac{1 \cdot \frac{a2}{b1}}{b2}}\]
    8. Simplified13.5

      \[\leadsto a1 \cdot \frac{\color{blue}{\frac{a2}{b1}}}{b2}\]
    9. Taylor expanded around -inf 4.1

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

    if -5.106090969630976e-119 < (* a1 a2) < -0.0 or 6.416315954955407e+192 < (* a1 a2)

    1. Initial program 18.2

      \[\frac{a1 \cdot a2}{b1 \cdot b2}\]
    2. Initial simplification6.2

      \[\leadsto \frac{a1}{b2} \cdot \frac{a2}{b1}\]
    3. Using strategy rm
    4. Applied div-inv6.2

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right)} \cdot \frac{a2}{b1}\]
    5. Applied associate-*l*6.2

      \[\leadsto \color{blue}{a1 \cdot \left(\frac{1}{b2} \cdot \frac{a2}{b1}\right)}\]
    6. Using strategy rm
    7. Applied associate-*r*6.2

      \[\leadsto \color{blue}{\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}}\]
    8. Using strategy rm
    9. Applied pow16.2

      \[\leadsto \left(a1 \cdot \frac{1}{b2}\right) \cdot \color{blue}{{\left(\frac{a2}{b1}\right)}^{1}}\]
    10. Applied pow16.2

      \[\leadsto \color{blue}{{\left(a1 \cdot \frac{1}{b2}\right)}^{1}} \cdot {\left(\frac{a2}{b1}\right)}^{1}\]
    11. Applied pow-prod-down6.2

      \[\leadsto \color{blue}{{\left(\left(a1 \cdot \frac{1}{b2}\right) \cdot \frac{a2}{b1}\right)}^{1}}\]
    12. Simplified6.3

      \[\leadsto {\color{blue}{\left(\frac{a1}{b1} \cdot \frac{a2}{b2}\right)}}^{1}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification6.0

    \[\leadsto \begin{array}{l} \mathbf{if}\;a1 \cdot a2 \le -7.627138752121106 \cdot 10^{+55}:\\ \;\;\;\;a1 \cdot \frac{\frac{a2}{b1}}{b2}\\ \mathbf{elif}\;a1 \cdot a2 \le -5.106090969630976 \cdot 10^{-119}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{elif}\;a1 \cdot a2 \le -0.0:\\ \;\;\;\;\frac{a1}{b1} \cdot \frac{a2}{b2}\\ \mathbf{elif}\;a1 \cdot a2 \le 6.416315954955407 \cdot 10^{+192}:\\ \;\;\;\;\frac{a1 \cdot a2}{b2 \cdot b1}\\ \mathbf{else}:\\ \;\;\;\;\frac{a1}{b1} \cdot \frac{a2}{b2}\\ \end{array}\]

Runtime

Time bar (total: 10.0s)Debug logProfile

herbie shell --seed 2018249 
(FPCore (a1 a2 b1 b2)
  :name "Quotient of products"

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

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