Average Error: 12.4 → 0.3
Time: 4.0m
Precision: 64
\[\left(\left(3 + \frac{2}{r \cdot r}\right) - \frac{\left(0.125 \cdot \left(3 - 2 \cdot v\right)\right) \cdot \left(\left(\left(w \cdot w\right) \cdot r\right) \cdot r\right)}{1 - v}\right) - 4.5\]
\[\left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \frac{3 + -2 \cdot v}{1 - v} \cdot \left(\left(w \cdot r\right) \cdot \left(\left(w \cdot r\right) \cdot 0.125\right)\right)\]

Error

Bits error versus v

Bits error versus w

Bits error versus r

Derivation

  1. Initial program 12.4

    \[\left(\left(3 + \frac{2}{r \cdot r}\right) - \frac{\left(0.125 \cdot \left(3 - 2 \cdot v\right)\right) \cdot \left(\left(\left(w \cdot w\right) \cdot r\right) \cdot r\right)}{1 - v}\right) - 4.5\]
  2. Simplified0.4

    \[\leadsto \color{blue}{\left(\left(3 + \frac{2}{r \cdot r}\right) - 4.5\right) - \frac{0.125}{\frac{\frac{1 - v}{3 - 2 \cdot v}}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}}\]
  3. Using strategy rm
  4. Applied associate-/r*0.4

    \[\leadsto \left(\left(3 + \color{blue}{\frac{\frac{2}{r}}{r}}\right) - 4.5\right) - \frac{0.125}{\frac{\frac{1 - v}{3 - 2 \cdot v}}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}\]
  5. Using strategy rm
  6. Applied div-inv0.4

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \frac{0.125}{\color{blue}{\frac{1 - v}{3 - 2 \cdot v} \cdot \frac{1}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}}\]
  7. Applied *-un-lft-identity0.4

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \frac{\color{blue}{1 \cdot 0.125}}{\frac{1 - v}{3 - 2 \cdot v} \cdot \frac{1}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}\]
  8. Applied times-frac0.4

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \color{blue}{\frac{1}{\frac{1 - v}{3 - 2 \cdot v}} \cdot \frac{0.125}{\frac{1}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}}\]
  9. Simplified0.4

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \color{blue}{\frac{v \cdot -2 + 3}{1 - v}} \cdot \frac{0.125}{\frac{1}{\left(w \cdot r\right) \cdot \left(w \cdot r\right)}}\]
  10. Simplified0.3

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \frac{v \cdot -2 + 3}{1 - v} \cdot \color{blue}{\left(\left(\left(w \cdot r\right) \cdot 0.125\right) \cdot \left(w \cdot r\right)\right)}\]
  11. Final simplification0.3

    \[\leadsto \left(\left(3 + \frac{\frac{2}{r}}{r}\right) - 4.5\right) - \frac{3 + -2 \cdot v}{1 - v} \cdot \left(\left(w \cdot r\right) \cdot \left(\left(w \cdot r\right) \cdot 0.125\right)\right)\]

Reproduce

herbie shell --seed 2019100 
(FPCore (v w r)
  :name "Rosa's TurbineBenchmark"
  (- (- (+ 3 (/ 2 (* r r))) (/ (* (* 0.125 (- 3 (* 2 v))) (* (* (* w w) r) r)) (- 1 v))) 4.5))