Disney BSSRDF, sample scattering profile, upper

Percentage Accurate: 95.9% → 96.7%
Time: 8.9s
Alternatives: 7
Speedup: 1.2×

Specification

?
\[\left(0 \leq s \land s \leq 256\right) \land \left(0.25 \leq u \land u \leq 1\right)\]
\[\begin{array}{l} \\ \left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \end{array} \]
(FPCore (s u)
 :precision binary32
 (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))
float code(float s, float u) {
	return (3.0f * s) * logf((1.0f / (1.0f - ((u - 0.25f) / 0.75f))));
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (3.0e0 * s) * log((1.0e0 / (1.0e0 - ((u - 0.25e0) / 0.75e0))))
end function
function code(s, u)
	return Float32(Float32(Float32(3.0) * s) * log(Float32(Float32(1.0) / Float32(Float32(1.0) - Float32(Float32(u - Float32(0.25)) / Float32(0.75))))))
end
function tmp = code(s, u)
	tmp = (single(3.0) * s) * log((single(1.0) / (single(1.0) - ((u - single(0.25)) / single(0.75)))));
end
\begin{array}{l}

\\
\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right)
\end{array}

Sampling outcomes in binary32 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 7 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: 95.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \end{array} \]
(FPCore (s u)
 :precision binary32
 (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))
float code(float s, float u) {
	return (3.0f * s) * logf((1.0f / (1.0f - ((u - 0.25f) / 0.75f))));
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (3.0e0 * s) * log((1.0e0 / (1.0e0 - ((u - 0.25e0) / 0.75e0))))
end function
function code(s, u)
	return Float32(Float32(Float32(3.0) * s) * log(Float32(Float32(1.0) / Float32(Float32(1.0) - Float32(Float32(u - Float32(0.25)) / Float32(0.75))))))
end
function tmp = code(s, u)
	tmp = (single(3.0) * s) * log((single(1.0) / (single(1.0) - ((u - single(0.25)) / single(0.75)))));
end
\begin{array}{l}

\\
\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right)
\end{array}

Alternative 1: 96.7% accurate, 1.1× speedup?

\[\begin{array}{l} \\ s \cdot \left(\log \left(1 + \frac{u - 0.25}{-0.75}\right) \cdot -3\right) \end{array} \]
(FPCore (s u)
 :precision binary32
 (* s (* (log (+ 1.0 (/ (- u 0.25) -0.75))) -3.0)))
float code(float s, float u) {
	return s * (logf((1.0f + ((u - 0.25f) / -0.75f))) * -3.0f);
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = s * (log((1.0e0 + ((u - 0.25e0) / (-0.75e0)))) * (-3.0e0))
end function
function code(s, u)
	return Float32(s * Float32(log(Float32(Float32(1.0) + Float32(Float32(u - Float32(0.25)) / Float32(-0.75)))) * Float32(-3.0)))
end
function tmp = code(s, u)
	tmp = s * (log((single(1.0) + ((u - single(0.25)) / single(-0.75)))) * single(-3.0));
end
\begin{array}{l}

\\
s \cdot \left(\log \left(1 + \frac{u - 0.25}{-0.75}\right) \cdot -3\right)
\end{array}
Derivation
  1. Initial program 96.1%

    \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)} \]
    2. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right)} \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \]
    3. associate-*l*N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)} \]
    4. *-commutativeN/A

      \[\leadsto 3 \cdot \color{blue}{\left(\log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \cdot s\right)} \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
    6. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
  4. Applied rewrites34.0%

    \[\leadsto \color{blue}{\left(-3 \cdot \mathsf{log1p}\left(-1.3333333333333333 \cdot \left(u - 0.25\right)\right)\right) \cdot s} \]
  5. Step-by-step derivation
    1. lift-log1p.f32N/A

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    2. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    3. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    4. lower-log.f3296.4

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right)}\right) \cdot s \]
    5. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    6. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    7. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)}\right)\right) \cdot s \]
    8. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{-4}{3}}\right)\right) \cdot s \]
    9. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(u - \frac{1}{4}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    10. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    11. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{1}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    12. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    13. lift--.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\frac{\color{blue}{u - \frac{1}{4}}}{\frac{3}{4}}\right)\right)\right)\right) \cdot s \]
    14. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}\right)}\right) \cdot s \]
    15. div-subN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{u}{\frac{3}{4}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)}\right)\right) \cdot s \]
    16. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{u \cdot \frac{1}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    17. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(u \cdot \color{blue}{\frac{4}{3}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    18. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{4}{3} \cdot u} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    19. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right)}\right)\right) \cdot s \]
    20. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{3}}\right)\right)\right)\right)\right) \cdot s \]
    21. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \color{blue}{\frac{-1}{3}}\right)\right)\right) \cdot s \]
    22. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{-1}{3} + \frac{4}{3} \cdot u\right)}\right)\right) \cdot s \]
    23. associate--r+N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(1 - \frac{-1}{3}\right) - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    24. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{4}{3}} - \frac{4}{3} \cdot u\right)\right) \cdot s \]
    25. lower--.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{4}{3} - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    26. lower-*.f3296.1

      \[\leadsto \left(-3 \cdot \log \left(1.3333333333333333 - \color{blue}{1.3333333333333333 \cdot u}\right)\right) \cdot s \]
  6. Applied rewrites96.1%

    \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right)}\right) \cdot s \]
  7. Step-by-step derivation
    1. lift--.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{4}{3} - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    2. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(1 - \frac{-1}{3}\right)} - \frac{4}{3} \cdot u\right)\right) \cdot s \]
    3. associate--r+N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 - \left(\frac{-1}{3} + \frac{4}{3} \cdot u\right)\right)}\right) \cdot s \]
    4. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u + \frac{-1}{3}\right)}\right)\right) \cdot s \]
    5. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{3}\right)\right)}\right)\right)\right) \cdot s \]
    6. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{1}{4}}{\frac{3}{4}}}\right)\right)\right)\right)\right) \cdot s \]
    7. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u - \frac{\frac{1}{4}}{\frac{3}{4}}\right)}\right)\right) \cdot s \]
    8. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{4}{3} \cdot u} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    9. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{u \cdot \frac{4}{3}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    10. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(u \cdot \color{blue}{\frac{1}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    11. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{u}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    12. div-subN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s \]
    13. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right)\right)}\right) \cdot s \]
    14. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right) + 1\right)}\right) \cdot s \]
    15. lower-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right) + 1\right)}\right) \cdot s \]
    16. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{1}{\frac{3}{4}}}\right)\right) + 1\right)\right) \cdot s \]
    17. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{4}{3}}\right)\right) + 1\right)\right) \cdot s \]
    18. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    19. lower-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    20. lower--.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right)} \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right) + 1\right)\right) \cdot s \]
    21. metadata-eval96.4

      \[\leadsto \left(-3 \cdot \log \left(\left(u - 0.25\right) \cdot \color{blue}{-1.3333333333333333} + 1\right)\right) \cdot s \]
  8. Applied rewrites96.4%

    \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(u - 0.25\right) \cdot -1.3333333333333333 + 1\right)}\right) \cdot s \]
  9. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{-4}{3}} + 1\right)\right) \cdot s \]
    2. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    3. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    4. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{1}{\frac{3}{4}}}\right)\right) + 1\right)\right) \cdot s \]
    5. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) + 1\right)\right) \cdot s \]
    6. distribute-neg-frac2N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{u - \frac{1}{4}}{\mathsf{neg}\left(\frac{3}{4}\right)}} + 1\right)\right) \cdot s \]
    7. lower-/.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{u - \frac{1}{4}}{\mathsf{neg}\left(\frac{3}{4}\right)}} + 1\right)\right) \cdot s \]
    8. metadata-eval96.6

      \[\leadsto \left(-3 \cdot \log \left(\frac{u - 0.25}{\color{blue}{-0.75}} + 1\right)\right) \cdot s \]
  10. Applied rewrites96.6%

    \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{u - 0.25}{-0.75}} + 1\right)\right) \cdot s \]
  11. Final simplification96.6%

    \[\leadsto s \cdot \left(\log \left(1 + \frac{u - 0.25}{-0.75}\right) \cdot -3\right) \]
  12. Add Preprocessing

Alternative 2: 96.4% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \left(\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right) \cdot -3\right) \cdot s \end{array} \]
(FPCore (s u)
 :precision binary32
 (* (* (log (+ (* -1.3333333333333333 (- u 0.25)) 1.0)) -3.0) s))
float code(float s, float u) {
	return (logf(((-1.3333333333333333f * (u - 0.25f)) + 1.0f)) * -3.0f) * s;
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (log((((-1.3333333333333333e0) * (u - 0.25e0)) + 1.0e0)) * (-3.0e0)) * s
end function
function code(s, u)
	return Float32(Float32(log(Float32(Float32(Float32(-1.3333333333333333) * Float32(u - Float32(0.25))) + Float32(1.0))) * Float32(-3.0)) * s)
end
function tmp = code(s, u)
	tmp = (log(((single(-1.3333333333333333) * (u - single(0.25))) + single(1.0))) * single(-3.0)) * s;
end
\begin{array}{l}

\\
\left(\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right) \cdot -3\right) \cdot s
\end{array}
Derivation
  1. Initial program 96.1%

    \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)} \]
    2. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right)} \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \]
    3. associate-*l*N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)} \]
    4. *-commutativeN/A

      \[\leadsto 3 \cdot \color{blue}{\left(\log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \cdot s\right)} \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
    6. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
  4. Applied rewrites34.0%

    \[\leadsto \color{blue}{\left(-3 \cdot \mathsf{log1p}\left(-1.3333333333333333 \cdot \left(u - 0.25\right)\right)\right) \cdot s} \]
  5. Step-by-step derivation
    1. lift-log1p.f32N/A

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    2. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    3. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    4. lower-log.f3296.4

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right)}\right) \cdot s \]
    5. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    6. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    7. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)}\right)\right) \cdot s \]
    8. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{-4}{3}}\right)\right) \cdot s \]
    9. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(u - \frac{1}{4}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    10. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    11. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{1}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    12. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    13. lift--.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\frac{\color{blue}{u - \frac{1}{4}}}{\frac{3}{4}}\right)\right)\right)\right) \cdot s \]
    14. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}\right)}\right) \cdot s \]
    15. div-subN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{u}{\frac{3}{4}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)}\right)\right) \cdot s \]
    16. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{u \cdot \frac{1}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    17. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(u \cdot \color{blue}{\frac{4}{3}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    18. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{4}{3} \cdot u} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    19. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right)}\right)\right) \cdot s \]
    20. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{3}}\right)\right)\right)\right)\right) \cdot s \]
    21. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \color{blue}{\frac{-1}{3}}\right)\right)\right) \cdot s \]
    22. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{-1}{3} + \frac{4}{3} \cdot u\right)}\right)\right) \cdot s \]
    23. associate--r+N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(1 - \frac{-1}{3}\right) - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    24. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{4}{3}} - \frac{4}{3} \cdot u\right)\right) \cdot s \]
    25. lower--.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{4}{3} - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    26. lower-*.f3296.1

      \[\leadsto \left(-3 \cdot \log \left(1.3333333333333333 - \color{blue}{1.3333333333333333 \cdot u}\right)\right) \cdot s \]
  6. Applied rewrites96.1%

    \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right)}\right) \cdot s \]
  7. Step-by-step derivation
    1. lift--.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{4}{3} - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    2. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(1 - \frac{-1}{3}\right)} - \frac{4}{3} \cdot u\right)\right) \cdot s \]
    3. associate--r+N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 - \left(\frac{-1}{3} + \frac{4}{3} \cdot u\right)\right)}\right) \cdot s \]
    4. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u + \frac{-1}{3}\right)}\right)\right) \cdot s \]
    5. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{3}\right)\right)}\right)\right)\right) \cdot s \]
    6. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\color{blue}{\frac{\frac{1}{4}}{\frac{3}{4}}}\right)\right)\right)\right)\right) \cdot s \]
    7. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u - \frac{\frac{1}{4}}{\frac{3}{4}}\right)}\right)\right) \cdot s \]
    8. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{4}{3} \cdot u} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    9. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{u \cdot \frac{4}{3}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    10. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(u \cdot \color{blue}{\frac{1}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    11. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{u}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    12. div-subN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s \]
    13. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right)\right)}\right) \cdot s \]
    14. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right) + 1\right)}\right) \cdot s \]
    15. lower-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(\mathsf{neg}\left(\frac{u - \frac{1}{4}}{\frac{3}{4}}\right)\right) + 1\right)}\right) \cdot s \]
    16. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{1}{\frac{3}{4}}}\right)\right) + 1\right)\right) \cdot s \]
    17. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{4}{3}}\right)\right) + 1\right)\right) \cdot s \]
    18. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    19. lower-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right) \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right)} + 1\right)\right) \cdot s \]
    20. lower--.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\left(u - \frac{1}{4}\right)} \cdot \left(\mathsf{neg}\left(\frac{4}{3}\right)\right) + 1\right)\right) \cdot s \]
    21. metadata-eval96.4

      \[\leadsto \left(-3 \cdot \log \left(\left(u - 0.25\right) \cdot \color{blue}{-1.3333333333333333} + 1\right)\right) \cdot s \]
  8. Applied rewrites96.4%

    \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(u - 0.25\right) \cdot -1.3333333333333333 + 1\right)}\right) \cdot s \]
  9. Final simplification96.4%

    \[\leadsto \left(\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right) \cdot -3\right) \cdot s \]
  10. Add Preprocessing

Alternative 3: 96.1% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \left(\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right) \cdot -3\right) \cdot s \end{array} \]
(FPCore (s u)
 :precision binary32
 (* (* (log (- 1.3333333333333333 (* 1.3333333333333333 u))) -3.0) s))
float code(float s, float u) {
	return (logf((1.3333333333333333f - (1.3333333333333333f * u))) * -3.0f) * s;
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = (log((1.3333333333333333e0 - (1.3333333333333333e0 * u))) * (-3.0e0)) * s
end function
function code(s, u)
	return Float32(Float32(log(Float32(Float32(1.3333333333333333) - Float32(Float32(1.3333333333333333) * u))) * Float32(-3.0)) * s)
end
function tmp = code(s, u)
	tmp = (log((single(1.3333333333333333) - (single(1.3333333333333333) * u))) * single(-3.0)) * s;
end
\begin{array}{l}

\\
\left(\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right) \cdot -3\right) \cdot s
\end{array}
Derivation
  1. Initial program 96.1%

    \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)} \]
    2. lift-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot s\right)} \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \]
    3. associate-*l*N/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)} \]
    4. *-commutativeN/A

      \[\leadsto 3 \cdot \color{blue}{\left(\log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right) \cdot s\right)} \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
    6. lower-*.f32N/A

      \[\leadsto \color{blue}{\left(3 \cdot \log \left(\frac{1}{1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right) \cdot s} \]
  4. Applied rewrites34.1%

    \[\leadsto \color{blue}{\left(-3 \cdot \mathsf{log1p}\left(-1.3333333333333333 \cdot \left(u - 0.25\right)\right)\right) \cdot s} \]
  5. Step-by-step derivation
    1. lift-log1p.f32N/A

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    2. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    3. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    4. lower-log.f3296.4

      \[\leadsto \left(-3 \cdot \color{blue}{\log \left(-1.3333333333333333 \cdot \left(u - 0.25\right) + 1\right)}\right) \cdot s \]
    5. lift-+.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right) + 1\right)}\right) \cdot s \]
    6. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 + \frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)\right)}\right) \cdot s \]
    7. lift-*.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\frac{-4}{3} \cdot \left(u - \frac{1}{4}\right)}\right)\right) \cdot s \]
    8. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(u - \frac{1}{4}\right) \cdot \frac{-4}{3}}\right)\right) \cdot s \]
    9. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(u - \frac{1}{4}\right) \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    10. distribute-rgt-neg-inN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \color{blue}{\left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \frac{4}{3}\right)\right)}\right)\right) \cdot s \]
    11. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\left(u - \frac{1}{4}\right) \cdot \color{blue}{\frac{1}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    12. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\color{blue}{\frac{u - \frac{1}{4}}{\frac{3}{4}}}\right)\right)\right)\right) \cdot s \]
    13. lift--.f32N/A

      \[\leadsto \left(-3 \cdot \log \left(1 + \left(\mathsf{neg}\left(\frac{\color{blue}{u - \frac{1}{4}}}{\frac{3}{4}}\right)\right)\right)\right) \cdot s \]
    14. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(1 - \frac{u - \frac{1}{4}}{\frac{3}{4}}\right)}\right) \cdot s \]
    15. div-subN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{u}{\frac{3}{4}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)}\right)\right) \cdot s \]
    16. div-invN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{u \cdot \frac{1}{\frac{3}{4}}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    17. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(u \cdot \color{blue}{\frac{4}{3}} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    18. *-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\color{blue}{\frac{4}{3} \cdot u} - \frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right) \cdot s \]
    19. sub-negN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\frac{\frac{1}{4}}{\frac{3}{4}}\right)\right)\right)}\right)\right) \cdot s \]
    20. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{3}}\right)\right)\right)\right)\right) \cdot s \]
    21. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \left(\frac{4}{3} \cdot u + \color{blue}{\frac{-1}{3}}\right)\right)\right) \cdot s \]
    22. +-commutativeN/A

      \[\leadsto \left(-3 \cdot \log \left(1 - \color{blue}{\left(\frac{-1}{3} + \frac{4}{3} \cdot u\right)}\right)\right) \cdot s \]
    23. associate--r+N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\left(1 - \frac{-1}{3}\right) - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    24. metadata-evalN/A

      \[\leadsto \left(-3 \cdot \log \left(\color{blue}{\frac{4}{3}} - \frac{4}{3} \cdot u\right)\right) \cdot s \]
    25. lower--.f32N/A

      \[\leadsto \left(-3 \cdot \log \color{blue}{\left(\frac{4}{3} - \frac{4}{3} \cdot u\right)}\right) \cdot s \]
    26. lower-*.f3296.1

      \[\leadsto \left(-3 \cdot \log \left(1.3333333333333333 - \color{blue}{1.3333333333333333 \cdot u}\right)\right) \cdot s \]
  6. Applied rewrites96.1%

    \[\leadsto \left(-3 \cdot \color{blue}{\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right)}\right) \cdot s \]
  7. Final simplification96.1%

    \[\leadsto \left(\log \left(1.3333333333333333 - 1.3333333333333333 \cdot u\right) \cdot -3\right) \cdot s \]
  8. Add Preprocessing

Alternative 4: 30.3% accurate, 4.6× speedup?

\[\begin{array}{l} \\ \left(\left(u \cdot u\right) \cdot s\right) \cdot \left(\frac{3}{u} + 1.5\right) \end{array} \]
(FPCore (s u) :precision binary32 (* (* (* u u) s) (+ (/ 3.0 u) 1.5)))
float code(float s, float u) {
	return ((u * u) * s) * ((3.0f / u) + 1.5f);
}
real(4) function code(s, u)
    real(4), intent (in) :: s
    real(4), intent (in) :: u
    code = ((u * u) * s) * ((3.0e0 / u) + 1.5e0)
end function
function code(s, u)
	return Float32(Float32(Float32(u * u) * s) * Float32(Float32(Float32(3.0) / u) + Float32(1.5)))
end
function tmp = code(s, u)
	tmp = ((u * u) * s) * ((single(3.0) / u) + single(1.5));
end
\begin{array}{l}

\\
\left(\left(u \cdot u\right) \cdot s\right) \cdot \left(\frac{3}{u} + 1.5\right)
\end{array}
Derivation
  1. Initial program 96.1%

    \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
  2. Add Preprocessing
  3. Taylor expanded in u around 0

    \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
    2. distribute-rgt-inN/A

      \[\leadsto \color{blue}{\left(\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(3 \cdot s\right) \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right) \]
    3. associate-+l+N/A

      \[\leadsto \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} \]
    4. *-commutativeN/A

      \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \color{blue}{\left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]
    6. associate-*r*N/A

      \[\leadsto \left(\color{blue}{3 \cdot \left(s \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
    7. distribute-lft-outN/A

      \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
    9. distribute-lft-outN/A

      \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
    10. associate-*l*N/A

      \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]
    12. *-commutativeN/A

      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]
    13. associate-*l*N/A

      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]
    14. associate-*l*N/A

      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
    15. distribute-lft-outN/A

      \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
  5. Applied rewrites14.9%

    \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(1.5 \cdot u\right) \cdot u\right)} \]
  6. Taylor expanded in u around inf

    \[\leadsto \frac{3}{2} \cdot \color{blue}{\left(s \cdot {u}^{2}\right)} \]
  7. Step-by-step derivation
    1. Applied rewrites26.5%

      \[\leadsto \left(\left(u \cdot s\right) \cdot 1.5\right) \cdot \color{blue}{u} \]
    2. Taylor expanded in u around inf

      \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
    3. Step-by-step derivation
      1. Applied rewrites30.4%

        \[\leadsto \left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot \color{blue}{\left(u \cdot u\right)} \]
      2. Step-by-step derivation
        1. Applied rewrites30.4%

          \[\leadsto \left(\frac{3}{u} + 1.5\right) \cdot \left(\left(u \cdot u\right) \cdot \color{blue}{s}\right) \]
        2. Final simplification30.4%

          \[\leadsto \left(\left(u \cdot u\right) \cdot s\right) \cdot \left(\frac{3}{u} + 1.5\right) \]
        3. Add Preprocessing

        Alternative 5: 30.3% accurate, 4.6× speedup?

        \[\begin{array}{l} \\ \left(\left(\left(\frac{3}{u} + 1.5\right) \cdot u\right) \cdot u\right) \cdot s \end{array} \]
        (FPCore (s u) :precision binary32 (* (* (* (+ (/ 3.0 u) 1.5) u) u) s))
        float code(float s, float u) {
        	return ((((3.0f / u) + 1.5f) * u) * u) * s;
        }
        
        real(4) function code(s, u)
            real(4), intent (in) :: s
            real(4), intent (in) :: u
            code = ((((3.0e0 / u) + 1.5e0) * u) * u) * s
        end function
        
        function code(s, u)
        	return Float32(Float32(Float32(Float32(Float32(Float32(3.0) / u) + Float32(1.5)) * u) * u) * s)
        end
        
        function tmp = code(s, u)
        	tmp = ((((single(3.0) / u) + single(1.5)) * u) * u) * s;
        end
        
        \begin{array}{l}
        
        \\
        \left(\left(\left(\frac{3}{u} + 1.5\right) \cdot u\right) \cdot u\right) \cdot s
        \end{array}
        
        Derivation
        1. Initial program 96.1%

          \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in u around 0

          \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
        4. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
          2. distribute-rgt-inN/A

            \[\leadsto \color{blue}{\left(\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(3 \cdot s\right) \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right) \]
          3. associate-+l+N/A

            \[\leadsto \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} \]
          4. *-commutativeN/A

            \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) \]
          5. +-commutativeN/A

            \[\leadsto \color{blue}{\left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]
          6. associate-*r*N/A

            \[\leadsto \left(\color{blue}{3 \cdot \left(s \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
          7. distribute-lft-outN/A

            \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
          8. *-commutativeN/A

            \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
          9. distribute-lft-outN/A

            \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
          10. associate-*l*N/A

            \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
          11. *-commutativeN/A

            \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]
          12. *-commutativeN/A

            \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]
          13. associate-*l*N/A

            \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]
          14. associate-*l*N/A

            \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
          15. distribute-lft-outN/A

            \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
        5. Applied rewrites14.9%

          \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(1.5 \cdot u\right) \cdot u\right)} \]
        6. Taylor expanded in u around inf

          \[\leadsto \frac{3}{2} \cdot \color{blue}{\left(s \cdot {u}^{2}\right)} \]
        7. Step-by-step derivation
          1. Applied rewrites26.5%

            \[\leadsto \left(\left(u \cdot s\right) \cdot 1.5\right) \cdot \color{blue}{u} \]
          2. Taylor expanded in u around inf

            \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
          3. Step-by-step derivation
            1. Applied rewrites30.4%

              \[\leadsto \left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot \color{blue}{\left(u \cdot u\right)} \]
            2. Step-by-step derivation
              1. Applied rewrites30.4%

                \[\leadsto \left(\left(\left(\frac{3}{u} + 1.5\right) \cdot u\right) \cdot u\right) \cdot s \]
              2. Add Preprocessing

              Alternative 6: 30.3% accurate, 4.6× speedup?

              \[\begin{array}{l} \\ \left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \cdot \left(u \cdot u\right) \end{array} \]
              (FPCore (s u) :precision binary32 (* (* (+ (/ 3.0 u) 1.5) s) (* u u)))
              float code(float s, float u) {
              	return (((3.0f / u) + 1.5f) * s) * (u * u);
              }
              
              real(4) function code(s, u)
                  real(4), intent (in) :: s
                  real(4), intent (in) :: u
                  code = (((3.0e0 / u) + 1.5e0) * s) * (u * u)
              end function
              
              function code(s, u)
              	return Float32(Float32(Float32(Float32(Float32(3.0) / u) + Float32(1.5)) * s) * Float32(u * u))
              end
              
              function tmp = code(s, u)
              	tmp = (((single(3.0) / u) + single(1.5)) * s) * (u * u);
              end
              
              \begin{array}{l}
              
              \\
              \left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \cdot \left(u \cdot u\right)
              \end{array}
              
              Derivation
              1. Initial program 96.1%

                \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
              2. Add Preprocessing
              3. Taylor expanded in u around 0

                \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
              4. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
                2. distribute-rgt-inN/A

                  \[\leadsto \color{blue}{\left(\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(3 \cdot s\right) \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right) \]
                3. associate-+l+N/A

                  \[\leadsto \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} \]
                4. *-commutativeN/A

                  \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) \]
                5. +-commutativeN/A

                  \[\leadsto \color{blue}{\left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]
                6. associate-*r*N/A

                  \[\leadsto \left(\color{blue}{3 \cdot \left(s \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                7. distribute-lft-outN/A

                  \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                8. *-commutativeN/A

                  \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                9. distribute-lft-outN/A

                  \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                10. associate-*l*N/A

                  \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                11. *-commutativeN/A

                  \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]
                12. *-commutativeN/A

                  \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]
                13. associate-*l*N/A

                  \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]
                14. associate-*l*N/A

                  \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
                15. distribute-lft-outN/A

                  \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
              5. Applied rewrites15.0%

                \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(1.5 \cdot u\right) \cdot u\right)} \]
              6. Taylor expanded in u around inf

                \[\leadsto \frac{3}{2} \cdot \color{blue}{\left(s \cdot {u}^{2}\right)} \]
              7. Step-by-step derivation
                1. Applied rewrites26.5%

                  \[\leadsto \left(\left(u \cdot s\right) \cdot 1.5\right) \cdot \color{blue}{u} \]
                2. Taylor expanded in u around inf

                  \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
                3. Step-by-step derivation
                  1. Applied rewrites30.4%

                    \[\leadsto \left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot \color{blue}{\left(u \cdot u\right)} \]
                  2. Final simplification30.4%

                    \[\leadsto \left(\left(\frac{3}{u} + 1.5\right) \cdot s\right) \cdot \left(u \cdot u\right) \]
                  3. Add Preprocessing

                  Alternative 7: 29.9% accurate, 12.6× speedup?

                  \[\begin{array}{l} \\ \left(3 \cdot u\right) \cdot s \end{array} \]
                  (FPCore (s u) :precision binary32 (* (* 3.0 u) s))
                  float code(float s, float u) {
                  	return (3.0f * u) * s;
                  }
                  
                  real(4) function code(s, u)
                      real(4), intent (in) :: s
                      real(4), intent (in) :: u
                      code = (3.0e0 * u) * s
                  end function
                  
                  function code(s, u)
                  	return Float32(Float32(Float32(3.0) * u) * s)
                  end
                  
                  function tmp = code(s, u)
                  	tmp = (single(3.0) * u) * s;
                  end
                  
                  \begin{array}{l}
                  
                  \\
                  \left(3 \cdot u\right) \cdot s
                  \end{array}
                  
                  Derivation
                  1. Initial program 96.1%

                    \[\left(3 \cdot s\right) \cdot \log \left(\frac{1}{1 - \frac{u - 0.25}{0.75}}\right) \]
                  2. Add Preprocessing
                  3. Taylor expanded in u around 0

                    \[\leadsto \color{blue}{3 \cdot \left(s \cdot \log \frac{3}{4}\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right)} \]
                  4. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right) + 3 \cdot s\right) + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)} \]
                    2. distribute-rgt-inN/A

                      \[\leadsto \color{blue}{\left(\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(3 \cdot s\right) \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right) \]
                    3. associate-+l+N/A

                      \[\leadsto \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right)} \]
                    4. *-commutativeN/A

                      \[\leadsto \color{blue}{u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} + \left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) \]
                    5. +-commutativeN/A

                      \[\leadsto \color{blue}{\left(\left(3 \cdot s\right) \cdot u + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right)} \]
                    6. associate-*r*N/A

                      \[\leadsto \left(\color{blue}{3 \cdot \left(s \cdot u\right)} + 3 \cdot \left(s \cdot \log \frac{3}{4}\right)\right) + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                    7. distribute-lft-outN/A

                      \[\leadsto \color{blue}{3 \cdot \left(s \cdot u + s \cdot \log \frac{3}{4}\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                    8. *-commutativeN/A

                      \[\leadsto \color{blue}{\left(s \cdot u + s \cdot \log \frac{3}{4}\right) \cdot 3} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                    9. distribute-lft-outN/A

                      \[\leadsto \color{blue}{\left(s \cdot \left(u + \log \frac{3}{4}\right)\right)} \cdot 3 + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                    10. associate-*l*N/A

                      \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right)} + u \cdot \left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \]
                    11. *-commutativeN/A

                      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\frac{3}{2} \cdot \left(s \cdot u\right)\right) \cdot u} \]
                    12. *-commutativeN/A

                      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(\left(s \cdot u\right) \cdot \frac{3}{2}\right)} \cdot u \]
                    13. associate-*l*N/A

                      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{\left(s \cdot u\right) \cdot \left(\frac{3}{2} \cdot u\right)} \]
                    14. associate-*l*N/A

                      \[\leadsto s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3\right) + \color{blue}{s \cdot \left(u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
                    15. distribute-lft-outN/A

                      \[\leadsto \color{blue}{s \cdot \left(\left(u + \log \frac{3}{4}\right) \cdot 3 + u \cdot \left(\frac{3}{2} \cdot u\right)\right)} \]
                  5. Applied rewrites14.9%

                    \[\leadsto \color{blue}{s \cdot \mathsf{fma}\left(\log 0.75 + u, 3, \left(1.5 \cdot u\right) \cdot u\right)} \]
                  6. Taylor expanded in u around inf

                    \[\leadsto \frac{3}{2} \cdot \color{blue}{\left(s \cdot {u}^{2}\right)} \]
                  7. Step-by-step derivation
                    1. Applied rewrites26.5%

                      \[\leadsto \left(\left(u \cdot s\right) \cdot 1.5\right) \cdot \color{blue}{u} \]
                    2. Taylor expanded in u around inf

                      \[\leadsto {u}^{2} \cdot \color{blue}{\left(\frac{3}{2} \cdot s + 3 \cdot \frac{s}{u}\right)} \]
                    3. Step-by-step derivation
                      1. Applied rewrites30.4%

                        \[\leadsto \left(s \cdot \left(\frac{3}{u} + 1.5\right)\right) \cdot \color{blue}{\left(u \cdot u\right)} \]
                      2. Taylor expanded in u around 0

                        \[\leadsto 3 \cdot \left(s \cdot \color{blue}{u}\right) \]
                      3. Step-by-step derivation
                        1. Applied rewrites30.3%

                          \[\leadsto \left(3 \cdot u\right) \cdot s \]
                        2. Add Preprocessing

                        Reproduce

                        ?
                        herbie shell --seed 2024259 
                        (FPCore (s u)
                          :name "Disney BSSRDF, sample scattering profile, upper"
                          :precision binary32
                          :pre (and (and (<= 0.0 s) (<= s 256.0)) (and (<= 0.25 u) (<= u 1.0)))
                          (* (* 3.0 s) (log (/ 1.0 (- 1.0 (/ (- u 0.25) 0.75))))))