Falkner and Boettcher, Equation (22+)

Percentage Accurate: 98.5% → 100.0%
Time: 4.3s
Alternatives: 6
Speedup: 2.1×

Specification

?
\[\begin{array}{l} \\ \frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \end{array} \]
(FPCore (v)
 :precision binary64
 (/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
\begin{array}{l}

\\
\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 6 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 98.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \end{array} \]
(FPCore (v)
 :precision binary64
 (/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
\begin{array}{l}

\\
\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}
\end{array}

Alternative 1: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(1 - v \cdot v\right)\right)\right)} \end{array} \]
(FPCore (v)
 :precision binary64
 (/ 4.0 (* (PI) (* 3.0 (* (sqrt (fma -6.0 (* v v) 2.0)) (- 1.0 (* v v)))))))
\begin{array}{l}

\\
\frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(1 - v \cdot v\right)\right)\right)}
\end{array}
Derivation
  1. Initial program 98.5%

    \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
    2. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    3. associate-*l*N/A

      \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{4}{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot 3\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
    6. associate-*l*N/A

      \[\leadsto \frac{4}{\color{blue}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)\right)}} \]
    7. lower-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)\right)}} \]
    8. lower-*.f64N/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(3 \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)\right)}} \]
    9. *-commutativeN/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \color{blue}{\left(\sqrt{2 - 6 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)}\right)} \]
    10. lower-*.f64100.0

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \color{blue}{\left(\sqrt{2 - 6 \cdot \left(v \cdot v\right)} \cdot \left(1 - v \cdot v\right)\right)}\right)} \]
    11. lift--.f64N/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\color{blue}{2 - 6 \cdot \left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
    12. lift-*.f64N/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{2 - \color{blue}{6 \cdot \left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
    13. fp-cancel-sub-sign-invN/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\color{blue}{2 + \left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right)}} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
    14. +-commutativeN/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\color{blue}{\left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right) + 2}} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
    15. lower-fma.f64N/A

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(6\right), v \cdot v, 2\right)}} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
    16. metadata-eval100.0

      \[\leadsto \frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\mathsf{fma}\left(\color{blue}{-6}, v \cdot v, 2\right)} \cdot \left(1 - v \cdot v\right)\right)\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto \frac{4}{\color{blue}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(1 - v \cdot v\right)\right)\right)}} \]
  5. Add Preprocessing

Alternative 2: 100.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{1.3333333333333333}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \end{array} \]
(FPCore (v)
 :precision binary64
 (/
  1.3333333333333333
  (* (sqrt (fma -6.0 (* v v) 2.0)) (* (- 1.0 (* v v)) (PI)))))
\begin{array}{l}

\\
\frac{1.3333333333333333}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}
\end{array}
Derivation
  1. Initial program 98.5%

    \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
    2. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{4}{\left(\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    4. associate-*l*N/A

      \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    5. associate-*l*N/A

      \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
    6. lower-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
    7. lower-*.f64N/A

      \[\leadsto \frac{4}{3 \cdot \color{blue}{\left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
    8. *-commutativeN/A

      \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
    9. lower-*.f6498.5

      \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
    10. lift--.f64N/A

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 - 6 \cdot \left(v \cdot v\right)}}\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{2 - \color{blue}{6 \cdot \left(v \cdot v\right)}}\right)} \]
    12. fp-cancel-sub-sign-invN/A

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 + \left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right)}}\right)} \]
    13. +-commutativeN/A

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right) + 2}}\right)} \]
    14. lower-fma.f64N/A

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(6\right), v \cdot v, 2\right)}}\right)} \]
    15. metadata-eval98.5

      \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(\color{blue}{-6}, v \cdot v, 2\right)}\right)} \]
  4. Applied rewrites98.5%

    \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
  5. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
    2. lift-*.f64N/A

      \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
    3. associate-/r*N/A

      \[\leadsto \color{blue}{\frac{\frac{4}{3}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
    4. metadata-evalN/A

      \[\leadsto \frac{\color{blue}{\frac{4}{3}}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}} \]
    5. lower-/.f64100.0

      \[\leadsto \color{blue}{\frac{1.3333333333333333}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
    6. lift-*.f64N/A

      \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
    7. *-commutativeN/A

      \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
    8. lower-*.f64100.0

      \[\leadsto \frac{1.3333333333333333}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
  6. Applied rewrites100.0%

    \[\leadsto \color{blue}{\frac{1.3333333333333333}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
  7. Add Preprocessing

Alternative 3: 98.9% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \frac{\frac{4}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right) \cdot 3} \end{array} \]
(FPCore (v)
 :precision binary64
 (/ (/ 4.0 (sqrt (fma -6.0 (* v v) 2.0))) (* (PI) 3.0)))
\begin{array}{l}

\\
\frac{\frac{4}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right) \cdot 3}
\end{array}
Derivation
  1. Initial program 98.5%

    \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
  2. Add Preprocessing
  3. Taylor expanded in v around 0

    \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
  4. Step-by-step derivation
    1. Applied rewrites97.7%

      \[\leadsto \frac{4}{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot 3\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    2. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{4}{\left(\mathsf{PI}\left(\right) \cdot 3\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{4}{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot 3\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{4}{\color{blue}{\sqrt{2 - 6 \cdot \left(v \cdot v\right)} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)}} \]
      4. lift--.f64N/A

        \[\leadsto \frac{4}{\sqrt{\color{blue}{2 - 6 \cdot \left(v \cdot v\right)}} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      5. lift-*.f64N/A

        \[\leadsto \frac{4}{\sqrt{2 - \color{blue}{6 \cdot \left(v \cdot v\right)}} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      6. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{4}{\sqrt{\color{blue}{2 + \left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right)}} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      7. metadata-evalN/A

        \[\leadsto \frac{4}{\sqrt{2 + \color{blue}{-6} \cdot \left(v \cdot v\right)} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      8. +-commutativeN/A

        \[\leadsto \frac{4}{\sqrt{\color{blue}{-6 \cdot \left(v \cdot v\right) + 2}} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      9. lift-fma.f64N/A

        \[\leadsto \frac{4}{\sqrt{\color{blue}{\mathsf{fma}\left(-6, v \cdot v, 2\right)}} \cdot \left(\mathsf{PI}\left(\right) \cdot 3\right)} \]
      10. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{4}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right) \cdot 3}} \]
      11. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{4}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right) \cdot 3}} \]
    3. Applied rewrites99.2%

      \[\leadsto \color{blue}{\frac{\frac{4}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right) \cdot 3}} \]
    4. Add Preprocessing

    Alternative 4: 98.9% accurate, 1.5× speedup?

    \[\begin{array}{l} \\ \frac{1.3333333333333333}{\left(1 - v \cdot v\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)} \end{array} \]
    (FPCore (v)
     :precision binary64
     (/ 1.3333333333333333 (* (- 1.0 (* v v)) (* (PI) (sqrt 2.0)))))
    \begin{array}{l}
    
    \\
    \frac{1.3333333333333333}{\left(1 - v \cdot v\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}
    \end{array}
    
    Derivation
    1. Initial program 98.5%

      \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
      3. lift-*.f64N/A

        \[\leadsto \frac{4}{\left(\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
      4. associate-*l*N/A

        \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
      5. associate-*l*N/A

        \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
      6. lower-*.f64N/A

        \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
      7. lower-*.f64N/A

        \[\leadsto \frac{4}{3 \cdot \color{blue}{\left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
      8. *-commutativeN/A

        \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
      9. lower-*.f6498.5

        \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
      10. lift--.f64N/A

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 - 6 \cdot \left(v \cdot v\right)}}\right)} \]
      11. lift-*.f64N/A

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{2 - \color{blue}{6 \cdot \left(v \cdot v\right)}}\right)} \]
      12. fp-cancel-sub-sign-invN/A

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 + \left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right)}}\right)} \]
      13. +-commutativeN/A

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right) + 2}}\right)} \]
      14. lower-fma.f64N/A

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(6\right), v \cdot v, 2\right)}}\right)} \]
      15. metadata-eval98.5

        \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(\color{blue}{-6}, v \cdot v, 2\right)}\right)} \]
    4. Applied rewrites98.5%

      \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
      3. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{4}{3}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
      4. metadata-evalN/A

        \[\leadsto \frac{\color{blue}{\frac{4}{3}}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}} \]
      5. lower-/.f64100.0

        \[\leadsto \color{blue}{\frac{1.3333333333333333}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
      7. *-commutativeN/A

        \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
      8. lower-*.f64100.0

        \[\leadsto \frac{1.3333333333333333}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
    6. Applied rewrites100.0%

      \[\leadsto \color{blue}{\frac{1.3333333333333333}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
    7. Taylor expanded in v around 0

      \[\leadsto \frac{\frac{4}{3}}{\sqrt{\color{blue}{2}} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \]
    8. Step-by-step derivation
      1. Applied rewrites99.2%

        \[\leadsto \frac{1.3333333333333333}{\sqrt{\color{blue}{2}} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\sqrt{2} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
        2. *-commutativeN/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{2}}} \]
        3. lift-*.f64N/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2}} \]
        4. associate-*l*N/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(1 - v \cdot v\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
        5. lower-*.f64N/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(1 - v \cdot v\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
        6. lower-*.f6499.2

          \[\leadsto \frac{1.3333333333333333}{\left(1 - v \cdot v\right) \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
      3. Applied rewrites99.2%

        \[\leadsto \frac{1.3333333333333333}{\color{blue}{\left(1 - v \cdot v\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \sqrt{2}\right)}} \]
      4. Add Preprocessing

      Alternative 5: 98.9% accurate, 1.5× speedup?

      \[\begin{array}{l} \\ \frac{1.3333333333333333}{\sqrt{2} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \end{array} \]
      (FPCore (v)
       :precision binary64
       (/ 1.3333333333333333 (* (sqrt 2.0) (* (- 1.0 (* v v)) (PI)))))
      \begin{array}{l}
      
      \\
      \frac{1.3333333333333333}{\sqrt{2} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}
      \end{array}
      
      Derivation
      1. Initial program 98.5%

        \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}} \]
        2. lift-*.f64N/A

          \[\leadsto \frac{4}{\color{blue}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
        3. lift-*.f64N/A

          \[\leadsto \frac{4}{\left(\color{blue}{\left(3 \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
        4. associate-*l*N/A

          \[\leadsto \frac{4}{\color{blue}{\left(3 \cdot \left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
        5. associate-*l*N/A

          \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
        7. lower-*.f64N/A

          \[\leadsto \frac{4}{3 \cdot \color{blue}{\left(\left(\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)}} \]
        8. *-commutativeN/A

          \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
        9. lower-*.f6498.5

          \[\leadsto \frac{4}{3 \cdot \left(\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}\right)} \]
        10. lift--.f64N/A

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 - 6 \cdot \left(v \cdot v\right)}}\right)} \]
        11. lift-*.f64N/A

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{2 - \color{blue}{6 \cdot \left(v \cdot v\right)}}\right)} \]
        12. fp-cancel-sub-sign-invN/A

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{2 + \left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right)}}\right)} \]
        13. +-commutativeN/A

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\left(\mathsf{neg}\left(6\right)\right) \cdot \left(v \cdot v\right) + 2}}\right)} \]
        14. lower-fma.f64N/A

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(6\right), v \cdot v, 2\right)}}\right)} \]
        15. metadata-eval98.5

          \[\leadsto \frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(\color{blue}{-6}, v \cdot v, 2\right)}\right)} \]
      4. Applied rewrites98.5%

        \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
      5. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{4}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \frac{4}{\color{blue}{3 \cdot \left(\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}\right)}} \]
        3. associate-/r*N/A

          \[\leadsto \color{blue}{\frac{\frac{4}{3}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
        4. metadata-evalN/A

          \[\leadsto \frac{\color{blue}{\frac{4}{3}}}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}} \]
        5. lower-/.f64100.0

          \[\leadsto \color{blue}{\frac{1.3333333333333333}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
        6. lift-*.f64N/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}} \]
        7. *-commutativeN/A

          \[\leadsto \frac{\frac{4}{3}}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
        8. lower-*.f64100.0

          \[\leadsto \frac{1.3333333333333333}{\color{blue}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
      6. Applied rewrites100.0%

        \[\leadsto \color{blue}{\frac{1.3333333333333333}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)}} \]
      7. Taylor expanded in v around 0

        \[\leadsto \frac{\frac{4}{3}}{\sqrt{\color{blue}{2}} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \]
      8. Step-by-step derivation
        1. Applied rewrites99.2%

          \[\leadsto \frac{1.3333333333333333}{\sqrt{\color{blue}{2}} \cdot \left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right)} \]
        2. Add Preprocessing

        Alternative 6: 98.9% accurate, 2.1× speedup?

        \[\begin{array}{l} \\ \sqrt{0.5} \cdot \frac{1.3333333333333333}{\mathsf{PI}\left(\right)} \end{array} \]
        (FPCore (v) :precision binary64 (* (sqrt 0.5) (/ 1.3333333333333333 (PI))))
        \begin{array}{l}
        
        \\
        \sqrt{0.5} \cdot \frac{1.3333333333333333}{\mathsf{PI}\left(\right)}
        \end{array}
        
        Derivation
        1. Initial program 98.5%

          \[\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}} \]
        2. Add Preprocessing
        3. Taylor expanded in v around 0

          \[\leadsto \color{blue}{\frac{4}{3} \cdot \frac{\sqrt{\frac{1}{2}}}{\mathsf{PI}\left(\right)}} \]
        4. Step-by-step derivation
          1. Applied rewrites97.6%

            \[\leadsto \color{blue}{\frac{\sqrt{0.5}}{\mathsf{PI}\left(\right)} \cdot 1.3333333333333333} \]
          2. Step-by-step derivation
            1. Applied rewrites99.2%

              \[\leadsto \sqrt{0.5} \cdot \color{blue}{\frac{1.3333333333333333}{\mathsf{PI}\left(\right)}} \]
            2. Add Preprocessing

            Reproduce

            ?
            herbie shell --seed 2025019 
            (FPCore (v)
              :name "Falkner and Boettcher, Equation (22+)"
              :precision binary64
              (/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))