sintan (problem 3.4.5)

Percentage Accurate: 1.5% → 99.9%
Time: 14.8s
Alternatives: 5
Speedup: 218.0×

Specification

?
\[-0.4 \leq \varepsilon \land \varepsilon \leq 0.4\]
\[\begin{array}{l} \\ \frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \end{array} \]
(FPCore (eps) :precision binary64 (/ (- eps (sin eps)) (- eps (tan eps))))
double code(double eps) {
	return (eps - sin(eps)) / (eps - tan(eps));
}
real(8) function code(eps)
    real(8), intent (in) :: eps
    code = (eps - sin(eps)) / (eps - tan(eps))
end function
public static double code(double eps) {
	return (eps - Math.sin(eps)) / (eps - Math.tan(eps));
}
def code(eps):
	return (eps - math.sin(eps)) / (eps - math.tan(eps))
function code(eps)
	return Float64(Float64(eps - sin(eps)) / Float64(eps - tan(eps)))
end
function tmp = code(eps)
	tmp = (eps - sin(eps)) / (eps - tan(eps));
end
code[eps_] := N[(N[(eps - N[Sin[eps], $MachinePrecision]), $MachinePrecision] / N[(eps - N[Tan[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon}
\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 5 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: 1.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \end{array} \]
(FPCore (eps) :precision binary64 (/ (- eps (sin eps)) (- eps (tan eps))))
double code(double eps) {
	return (eps - sin(eps)) / (eps - tan(eps));
}
real(8) function code(eps)
    real(8), intent (in) :: eps
    code = (eps - sin(eps)) / (eps - tan(eps))
end function
public static double code(double eps) {
	return (eps - Math.sin(eps)) / (eps - Math.tan(eps));
}
def code(eps):
	return (eps - math.sin(eps)) / (eps - math.tan(eps))
function code(eps)
	return Float64(Float64(eps - sin(eps)) / Float64(eps - tan(eps)))
end
function tmp = code(eps)
	tmp = (eps - sin(eps)) / (eps - tan(eps));
end
code[eps_] := N[(N[(eps - N[Sin[eps], $MachinePrecision]), $MachinePrecision] / N[(eps - N[Tan[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon}
\end{array}

Alternative 1: 99.9% accurate, 4.5× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\left(\left(\varepsilon \cdot \varepsilon\right) \cdot 0.00024107142857142857 - 0.009642857142857142\right) \cdot \left(\varepsilon \cdot \varepsilon\right), \varepsilon \cdot \varepsilon, 0.225 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \end{array} \]
(FPCore (eps)
 :precision binary64
 (fma
  (*
   (- (* (* eps eps) 0.00024107142857142857) 0.009642857142857142)
   (* eps eps))
  (* eps eps)
  (- (* 0.225 (* eps eps)) 0.5)))
double code(double eps) {
	return fma(((((eps * eps) * 0.00024107142857142857) - 0.009642857142857142) * (eps * eps)), (eps * eps), ((0.225 * (eps * eps)) - 0.5));
}
function code(eps)
	return fma(Float64(Float64(Float64(Float64(eps * eps) * 0.00024107142857142857) - 0.009642857142857142) * Float64(eps * eps)), Float64(eps * eps), Float64(Float64(0.225 * Float64(eps * eps)) - 0.5))
end
code[eps_] := N[(N[(N[(N[(N[(eps * eps), $MachinePrecision] * 0.00024107142857142857), $MachinePrecision] - 0.009642857142857142), $MachinePrecision] * N[(eps * eps), $MachinePrecision]), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + N[(N[(0.225 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\left(\left(\varepsilon \cdot \varepsilon\right) \cdot 0.00024107142857142857 - 0.009642857142857142\right) \cdot \left(\varepsilon \cdot \varepsilon\right), \varepsilon \cdot \varepsilon, 0.225 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right)
\end{array}
Derivation
  1. Initial program 1.3%

    \[\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

    \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) - \frac{1}{2}} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto {\varepsilon}^{2} \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right) + \frac{9}{40}\right)} - \frac{1}{2} \]
    2. distribute-lft-inN/A

      \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + {\varepsilon}^{2} \cdot \frac{9}{40}\right)} - \frac{1}{2} \]
    3. *-commutativeN/A

      \[\leadsto \left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2}}\right) - \frac{1}{2} \]
    4. associate--l+N/A

      \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}\right) \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)} + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    6. lower-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
    7. pow-sqrN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    8. lower-pow.f64N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    9. metadata-evalN/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{\color{blue}{4}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    10. lower--.f64N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    11. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2}} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    12. unpow2N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    13. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
    14. lower--.f64N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}}\right) \]
    15. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
    16. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
    17. unpow2N/A

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \frac{9}{40} - \frac{1}{2}\right) \]
    18. lower-*.f6499.9

      \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot 0.225 - 0.5\right) \]
  5. Applied rewrites99.9%

    \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5\right)} \]
  6. Step-by-step derivation
    1. Applied rewrites99.9%

      \[\leadsto \mathsf{fma}\left(\left(\left(\varepsilon \cdot \varepsilon\right) \cdot 0.00024107142857142857 - 0.009642857142857142\right) \cdot \left(\varepsilon \cdot \varepsilon\right), \color{blue}{\varepsilon \cdot \varepsilon}, 0.225 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.5\right) \]
    2. Add Preprocessing

    Alternative 2: 99.9% accurate, 5.7× speedup?

    \[\begin{array}{l} \\ \left(\mathsf{fma}\left(0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5 \end{array} \]
    (FPCore (eps)
     :precision binary64
     (-
      (*
       (*
        (fma
         (- (* 0.00024107142857142857 (* eps eps)) 0.009642857142857142)
         (* eps eps)
         0.225)
        eps)
       eps)
      0.5))
    double code(double eps) {
    	return ((fma(((0.00024107142857142857 * (eps * eps)) - 0.009642857142857142), (eps * eps), 0.225) * eps) * eps) - 0.5;
    }
    
    function code(eps)
    	return Float64(Float64(Float64(fma(Float64(Float64(0.00024107142857142857 * Float64(eps * eps)) - 0.009642857142857142), Float64(eps * eps), 0.225) * eps) * eps) - 0.5)
    end
    
    code[eps_] := N[(N[(N[(N[(N[(N[(0.00024107142857142857 * N[(eps * eps), $MachinePrecision]), $MachinePrecision] - 0.009642857142857142), $MachinePrecision] * N[(eps * eps), $MachinePrecision] + 0.225), $MachinePrecision] * eps), $MachinePrecision] * eps), $MachinePrecision] - 0.5), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\mathsf{fma}\left(0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5
    \end{array}
    
    Derivation
    1. Initial program 1.3%

      \[\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) - \frac{1}{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto {\varepsilon}^{2} \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right) + \frac{9}{40}\right)} - \frac{1}{2} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + {\varepsilon}^{2} \cdot \frac{9}{40}\right)} - \frac{1}{2} \]
      3. *-commutativeN/A

        \[\leadsto \left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2}}\right) - \frac{1}{2} \]
      4. associate--l+N/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
      5. associate-*r*N/A

        \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}\right) \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)} + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      6. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
      7. pow-sqrN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      8. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{\color{blue}{4}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      10. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      11. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2}} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      13. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      14. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}}\right) \]
      15. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
      16. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
      17. unpow2N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \frac{9}{40} - \frac{1}{2}\right) \]
      18. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot 0.225 - 0.5\right) \]
    5. Applied rewrites99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5\right)} \]
    6. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) - \frac{1}{2}} \]
    7. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) - \frac{1}{2}} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) \cdot {\varepsilon}^{2}} - \frac{1}{2} \]
      3. unpow2N/A

        \[\leadsto \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{1}{2} \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) \cdot \varepsilon\right) \cdot \varepsilon} - \frac{1}{2} \]
      5. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) \cdot \varepsilon\right) \cdot \varepsilon} - \frac{1}{2} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) \cdot \varepsilon\right)} \cdot \varepsilon - \frac{1}{2} \]
      7. +-commutativeN/A

        \[\leadsto \left(\color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right) + \frac{9}{40}\right)} \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      8. *-commutativeN/A

        \[\leadsto \left(\left(\color{blue}{\left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right) \cdot {\varepsilon}^{2}} + \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      9. lower-fma.f64N/A

        \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, {\varepsilon}^{2}, \frac{9}{40}\right)} \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      10. lower--.f64N/A

        \[\leadsto \left(\mathsf{fma}\left(\color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}}, {\varepsilon}^{2}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      11. lower-*.f64N/A

        \[\leadsto \left(\mathsf{fma}\left(\color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2}} - \frac{27}{2800}, {\varepsilon}^{2}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      12. unpow2N/A

        \[\leadsto \left(\mathsf{fma}\left(\frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, {\varepsilon}^{2}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      13. lower-*.f64N/A

        \[\leadsto \left(\mathsf{fma}\left(\frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, {\varepsilon}^{2}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      14. unpow2N/A

        \[\leadsto \left(\mathsf{fma}\left(\frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\varepsilon \cdot \varepsilon}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      15. lower-*.f6499.9

        \[\leadsto \left(\mathsf{fma}\left(0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \color{blue}{\varepsilon \cdot \varepsilon}, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5 \]
    8. Applied rewrites99.9%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5} \]
    9. Add Preprocessing

    Alternative 3: 99.9% accurate, 8.7× speedup?

    \[\begin{array}{l} \\ \left(\mathsf{fma}\left(-0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5 \end{array} \]
    (FPCore (eps)
     :precision binary64
     (- (* (* (fma -0.009642857142857142 (* eps eps) 0.225) eps) eps) 0.5))
    double code(double eps) {
    	return ((fma(-0.009642857142857142, (eps * eps), 0.225) * eps) * eps) - 0.5;
    }
    
    function code(eps)
    	return Float64(Float64(Float64(fma(-0.009642857142857142, Float64(eps * eps), 0.225) * eps) * eps) - 0.5)
    end
    
    code[eps_] := N[(N[(N[(N[(-0.009642857142857142 * N[(eps * eps), $MachinePrecision] + 0.225), $MachinePrecision] * eps), $MachinePrecision] * eps), $MachinePrecision] - 0.5), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\mathsf{fma}\left(-0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5
    \end{array}
    
    Derivation
    1. Initial program 1.3%

      \[\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + {\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) - \frac{1}{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto {\varepsilon}^{2} \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right) + \frac{9}{40}\right)} - \frac{1}{2} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + {\varepsilon}^{2} \cdot \frac{9}{40}\right)} - \frac{1}{2} \]
      3. *-commutativeN/A

        \[\leadsto \left({\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2}}\right) - \frac{1}{2} \]
      4. associate--l+N/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left({\varepsilon}^{2} \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)\right) + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
      5. associate-*r*N/A

        \[\leadsto \color{blue}{\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}\right) \cdot \left(\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}\right)} + \left(\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      6. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{2} \cdot {\varepsilon}^{2}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right)} \]
      7. pow-sqrN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      8. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{\varepsilon}^{\left(2 \cdot 2\right)}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{\color{blue}{4}}, \frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      10. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2} - \frac{27}{2800}}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      11. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \color{blue}{\frac{27}{112000} \cdot {\varepsilon}^{2}} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      13. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{27}{2800}, \frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}\right) \]
      14. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}}\right) \]
      15. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
      16. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2}\right) \]
      17. unpow2N/A

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, \frac{27}{112000} \cdot \left(\varepsilon \cdot \varepsilon\right) - \frac{27}{2800}, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \frac{9}{40} - \frac{1}{2}\right) \]
      18. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot 0.225 - 0.5\right) \]
    5. Applied rewrites99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left({\varepsilon}^{4}, 0.00024107142857142857 \cdot \left(\varepsilon \cdot \varepsilon\right) - 0.009642857142857142, \left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5\right)} \]
    6. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) - \frac{1}{2}} \]
    7. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) - \frac{1}{2}} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) \cdot {\varepsilon}^{2}} - \frac{1}{2} \]
      3. unpow2N/A

        \[\leadsto \left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} - \frac{1}{2} \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) \cdot \varepsilon\right) \cdot \varepsilon} - \frac{1}{2} \]
      5. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) \cdot \varepsilon\right) \cdot \varepsilon} - \frac{1}{2} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{9}{40} + \frac{-27}{2800} \cdot {\varepsilon}^{2}\right) \cdot \varepsilon\right)} \cdot \varepsilon - \frac{1}{2} \]
      7. +-commutativeN/A

        \[\leadsto \left(\color{blue}{\left(\frac{-27}{2800} \cdot {\varepsilon}^{2} + \frac{9}{40}\right)} \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      8. lower-fma.f64N/A

        \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\frac{-27}{2800}, {\varepsilon}^{2}, \frac{9}{40}\right)} \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      9. unpow2N/A

        \[\leadsto \left(\mathsf{fma}\left(\frac{-27}{2800}, \color{blue}{\varepsilon \cdot \varepsilon}, \frac{9}{40}\right) \cdot \varepsilon\right) \cdot \varepsilon - \frac{1}{2} \]
      10. lower-*.f6499.7

        \[\leadsto \left(\mathsf{fma}\left(-0.009642857142857142, \color{blue}{\varepsilon \cdot \varepsilon}, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5 \]
    8. Applied rewrites99.7%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-0.009642857142857142, \varepsilon \cdot \varepsilon, 0.225\right) \cdot \varepsilon\right) \cdot \varepsilon - 0.5} \]
    9. Add Preprocessing

    Alternative 4: 99.7% accurate, 15.6× speedup?

    \[\begin{array}{l} \\ \left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5 \end{array} \]
    (FPCore (eps) :precision binary64 (- (* (* eps eps) 0.225) 0.5))
    double code(double eps) {
    	return ((eps * eps) * 0.225) - 0.5;
    }
    
    real(8) function code(eps)
        real(8), intent (in) :: eps
        code = ((eps * eps) * 0.225d0) - 0.5d0
    end function
    
    public static double code(double eps) {
    	return ((eps * eps) * 0.225) - 0.5;
    }
    
    def code(eps):
    	return ((eps * eps) * 0.225) - 0.5
    
    function code(eps)
    	return Float64(Float64(Float64(eps * eps) * 0.225) - 0.5)
    end
    
    function tmp = code(eps)
    	tmp = ((eps * eps) * 0.225) - 0.5;
    end
    
    code[eps_] := N[(N[(N[(eps * eps), $MachinePrecision] * 0.225), $MachinePrecision] - 0.5), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5
    \end{array}
    
    Derivation
    1. Initial program 1.3%

      \[\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}} \]
    4. Step-by-step derivation
      1. lower--.f64N/A

        \[\leadsto \color{blue}{\frac{9}{40} \cdot {\varepsilon}^{2} - \frac{1}{2}} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2} \]
      3. lower-*.f64N/A

        \[\leadsto \color{blue}{{\varepsilon}^{2} \cdot \frac{9}{40}} - \frac{1}{2} \]
      4. unpow2N/A

        \[\leadsto \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot \frac{9}{40} - \frac{1}{2} \]
      5. lower-*.f6499.6

        \[\leadsto \color{blue}{\left(\varepsilon \cdot \varepsilon\right)} \cdot 0.225 - 0.5 \]
    5. Applied rewrites99.6%

      \[\leadsto \color{blue}{\left(\varepsilon \cdot \varepsilon\right) \cdot 0.225 - 0.5} \]
    6. Add Preprocessing

    Alternative 5: 99.2% accurate, 218.0× speedup?

    \[\begin{array}{l} \\ -0.5 \end{array} \]
    (FPCore (eps) :precision binary64 -0.5)
    double code(double eps) {
    	return -0.5;
    }
    
    real(8) function code(eps)
        real(8), intent (in) :: eps
        code = -0.5d0
    end function
    
    public static double code(double eps) {
    	return -0.5;
    }
    
    def code(eps):
    	return -0.5
    
    function code(eps)
    	return -0.5
    end
    
    function tmp = code(eps)
    	tmp = -0.5;
    end
    
    code[eps_] := -0.5
    
    \begin{array}{l}
    
    \\
    -0.5
    \end{array}
    
    Derivation
    1. Initial program 1.3%

      \[\frac{\varepsilon - \sin \varepsilon}{\varepsilon - \tan \varepsilon} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{-1}{2}} \]
    4. Step-by-step derivation
      1. Applied rewrites99.1%

        \[\leadsto \color{blue}{-0.5} \]
      2. Add Preprocessing

      Developer Target 1: 99.7% accurate, 15.6× speedup?

      \[\begin{array}{l} \\ \left(0.225 \cdot \varepsilon\right) \cdot \varepsilon - 0.5 \end{array} \]
      (FPCore (eps) :precision binary64 (- (* (* 0.225 eps) eps) 0.5))
      double code(double eps) {
      	return ((0.225 * eps) * eps) - 0.5;
      }
      
      real(8) function code(eps)
          real(8), intent (in) :: eps
          code = ((0.225d0 * eps) * eps) - 0.5d0
      end function
      
      public static double code(double eps) {
      	return ((0.225 * eps) * eps) - 0.5;
      }
      
      def code(eps):
      	return ((0.225 * eps) * eps) - 0.5
      
      function code(eps)
      	return Float64(Float64(Float64(0.225 * eps) * eps) - 0.5)
      end
      
      function tmp = code(eps)
      	tmp = ((0.225 * eps) * eps) - 0.5;
      end
      
      code[eps_] := N[(N[(N[(0.225 * eps), $MachinePrecision] * eps), $MachinePrecision] - 0.5), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \left(0.225 \cdot \varepsilon\right) \cdot \varepsilon - 0.5
      \end{array}
      

      Reproduce

      ?
      herbie shell --seed 2024339 
      (FPCore (eps)
        :name "sintan (problem 3.4.5)"
        :precision binary64
        :pre (and (<= -0.4 eps) (<= eps 0.4))
      
        :alt
        (! :herbie-platform default (- (* 9/40 eps eps) 1/2))
      
        (/ (- eps (sin eps)) (- eps (tan eps))))