ENA, Section 1.4, Exercise 4a

Percentage Accurate: 53.0% → 99.6%
Time: 14.2s
Alternatives: 10
Speedup: 19.5×

Specification

?
\[-1 \leq x \land x \leq 1\]
\[\begin{array}{l} \\ \frac{x - \sin x}{\tan x} \end{array} \]
(FPCore (x) :precision binary64 (/ (- x (sin x)) (tan x)))
double code(double x) {
	return (x - sin(x)) / tan(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x - sin(x)) / tan(x)
end function
public static double code(double x) {
	return (x - Math.sin(x)) / Math.tan(x);
}
def code(x):
	return (x - math.sin(x)) / math.tan(x)
function code(x)
	return Float64(Float64(x - sin(x)) / tan(x))
end
function tmp = code(x)
	tmp = (x - sin(x)) / tan(x);
end
code[x_] := N[(N[(x - N[Sin[x], $MachinePrecision]), $MachinePrecision] / N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x - \sin x}{\tan x}
\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 10 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: 53.0% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 4.4× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (fma
   x
   0.16666666666666666
   (*
    (*
     (*
      (fma
       (fma (* x x) -0.00023644179894179894 -0.0007275132275132275)
       (* x x)
       -0.06388888888888888)
      x)
     x)
    x))
  x))
double code(double x) {
	return fma(x, 0.16666666666666666, (((fma(fma((x * x), -0.00023644179894179894, -0.0007275132275132275), (x * x), -0.06388888888888888) * x) * x) * x)) * x;
}
function code(x)
	return Float64(fma(x, 0.16666666666666666, Float64(Float64(Float64(fma(fma(Float64(x * x), -0.00023644179894179894, -0.0007275132275132275), Float64(x * x), -0.06388888888888888) * x) * x) * x)) * x)
end
code[x_] := N[(N[(x * 0.16666666666666666 + N[(N[(N[(N[(N[(N[(x * x), $MachinePrecision] * -0.00023644179894179894 + -0.0007275132275132275), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x
\end{array}
Derivation
  1. Initial program 52.4%

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

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
  4. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
    2. unpow2N/A

      \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
    3. associate-*r*N/A

      \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
    4. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
  5. Applied rewrites99.5%

    \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
  6. Step-by-step derivation
    1. Applied rewrites99.5%

      \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
    2. Add Preprocessing

    Alternative 2: 99.6% accurate, 4.9× speedup?

    \[\begin{array}{l} \\ \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x \end{array} \]
    (FPCore (x)
     :precision binary64
     (*
      (*
       (fma
        (fma
         (fma -0.00023644179894179894 (* x x) -0.0007275132275132275)
         (* x x)
         -0.06388888888888888)
        (* x x)
        0.16666666666666666)
       x)
      x))
    double code(double x) {
    	return (fma(fma(fma(-0.00023644179894179894, (x * x), -0.0007275132275132275), (x * x), -0.06388888888888888), (x * x), 0.16666666666666666) * x) * x;
    }
    
    function code(x)
    	return Float64(Float64(fma(fma(fma(-0.00023644179894179894, Float64(x * x), -0.0007275132275132275), Float64(x * x), -0.06388888888888888), Float64(x * x), 0.16666666666666666) * x) * x)
    end
    
    code[x_] := N[(N[(N[(N[(N[(-0.00023644179894179894 * N[(x * x), $MachinePrecision] + -0.0007275132275132275), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
    \end{array}
    
    Derivation
    1. Initial program 52.4%

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

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
      2. unpow2N/A

        \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
      4. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
    5. Applied rewrites99.5%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
    6. Add Preprocessing

    Alternative 3: 99.5% accurate, 5.7× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x \end{array} \]
    (FPCore (x)
     :precision binary64
     (*
      (fma
       (* (* (fma -0.0007275132275132275 (* x x) -0.06388888888888888) x) x)
       x
       (* 0.16666666666666666 x))
      x))
    double code(double x) {
    	return fma(((fma(-0.0007275132275132275, (x * x), -0.06388888888888888) * x) * x), x, (0.16666666666666666 * x)) * x;
    }
    
    function code(x)
    	return Float64(fma(Float64(Float64(fma(-0.0007275132275132275, Float64(x * x), -0.06388888888888888) * x) * x), x, Float64(0.16666666666666666 * x)) * x)
    end
    
    code[x_] := N[(N[(N[(N[(N[(-0.0007275132275132275 * N[(x * x), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * x + N[(0.16666666666666666 * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x
    \end{array}
    
    Derivation
    1. Initial program 52.4%

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

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
      2. unpow2N/A

        \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
      4. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
    5. Applied rewrites99.5%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
    6. Step-by-step derivation
      1. Applied rewrites99.5%

        \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
      2. Taylor expanded in x around 0

        \[\leadsto \mathsf{fma}\left(x, \frac{1}{6}, \left(\left(x \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \cdot x\right) \cdot x\right) \cdot x \]
      3. Step-by-step derivation
        1. Applied rewrites99.3%

          \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
        2. Step-by-step derivation
          1. Applied rewrites99.3%

            \[\leadsto \mathsf{fma}\left(\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x \]
          2. Add Preprocessing

          Alternative 4: 99.5% accurate, 5.7× speedup?

          \[\begin{array}{l} \\ \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \end{array} \]
          (FPCore (x)
           :precision binary64
           (*
            (fma
             x
             0.16666666666666666
             (* (* (* (fma (* x x) -0.0007275132275132275 -0.06388888888888888) x) x) x))
            x))
          double code(double x) {
          	return fma(x, 0.16666666666666666, (((fma((x * x), -0.0007275132275132275, -0.06388888888888888) * x) * x) * x)) * x;
          }
          
          function code(x)
          	return Float64(fma(x, 0.16666666666666666, Float64(Float64(Float64(fma(Float64(x * x), -0.0007275132275132275, -0.06388888888888888) * x) * x) * x)) * x)
          end
          
          code[x_] := N[(N[(x * 0.16666666666666666 + N[(N[(N[(N[(N[(x * x), $MachinePrecision] * -0.0007275132275132275 + -0.06388888888888888), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x
          \end{array}
          
          Derivation
          1. Initial program 52.4%

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

            \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
            2. unpow2N/A

              \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
            3. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
            4. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
          5. Applied rewrites99.5%

            \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
          6. Step-by-step derivation
            1. Applied rewrites99.5%

              \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
            2. Taylor expanded in x around 0

              \[\leadsto \mathsf{fma}\left(x, \frac{1}{6}, \left(\left(x \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \cdot x\right) \cdot x\right) \cdot x \]
            3. Step-by-step derivation
              1. Applied rewrites99.3%

                \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(x \cdot x, -0.0007275132275132275, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
              2. Add Preprocessing

              Alternative 5: 99.5% accurate, 6.5× speedup?

              \[\begin{array}{l} \\ \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x \end{array} \]
              (FPCore (x)
               :precision binary64
               (*
                (*
                 (fma
                  (fma -0.0007275132275132275 (* x x) -0.06388888888888888)
                  (* x x)
                  0.16666666666666666)
                 x)
                x))
              double code(double x) {
              	return (fma(fma(-0.0007275132275132275, (x * x), -0.06388888888888888), (x * x), 0.16666666666666666) * x) * x;
              }
              
              function code(x)
              	return Float64(Float64(fma(fma(-0.0007275132275132275, Float64(x * x), -0.06388888888888888), Float64(x * x), 0.16666666666666666) * x) * x)
              end
              
              code[x_] := N[(N[(N[(N[(-0.0007275132275132275 * N[(x * x), $MachinePrecision] + -0.06388888888888888), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
              \end{array}
              
              Derivation
              1. Initial program 52.4%

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

                \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)} \]
              4. Step-by-step derivation
                1. unpow2N/A

                  \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \]
                2. associate-*l*N/A

                  \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right)} \]
                3. *-commutativeN/A

                  \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right) \cdot x} \]
                4. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right)\right) \cdot x} \]
                5. *-commutativeN/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \cdot x\right)} \cdot x \]
                6. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right)\right) \cdot x\right)} \cdot x \]
                7. +-commutativeN/A

                  \[\leadsto \left(\color{blue}{\left({x}^{2} \cdot \left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) + \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                8. *-commutativeN/A

                  \[\leadsto \left(\left(\color{blue}{\left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}\right) \cdot {x}^{2}} + \frac{1}{6}\right) \cdot x\right) \cdot x \]
                9. lower-fma.f64N/A

                  \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\frac{-11}{15120} \cdot {x}^{2} - \frac{23}{360}, {x}^{2}, \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                10. sub-negN/A

                  \[\leadsto \left(\mathsf{fma}\left(\color{blue}{\frac{-11}{15120} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{23}{360}\right)\right)}, {x}^{2}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                11. metadata-evalN/A

                  \[\leadsto \left(\mathsf{fma}\left(\frac{-11}{15120} \cdot {x}^{2} + \color{blue}{\frac{-23}{360}}, {x}^{2}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                12. lower-fma.f64N/A

                  \[\leadsto \left(\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{-11}{15120}, {x}^{2}, \frac{-23}{360}\right)}, {x}^{2}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                13. unpow2N/A

                  \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{-11}{15120}, \color{blue}{x \cdot x}, \frac{-23}{360}\right), {x}^{2}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                14. lower-*.f64N/A

                  \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{-11}{15120}, \color{blue}{x \cdot x}, \frac{-23}{360}\right), {x}^{2}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                15. unpow2N/A

                  \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{-11}{15120}, x \cdot x, \frac{-23}{360}\right), \color{blue}{x \cdot x}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                16. lower-*.f6499.3

                  \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right), \color{blue}{x \cdot x}, 0.16666666666666666\right) \cdot x\right) \cdot x \]
              5. Applied rewrites99.3%

                \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.0007275132275132275, x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
              6. Add Preprocessing

              Alternative 6: 99.4% accurate, 8.0× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(-0.06388888888888888 \cdot \left(x \cdot x\right), x, 0.16666666666666666 \cdot x\right) \cdot x \end{array} \]
              (FPCore (x)
               :precision binary64
               (* (fma (* -0.06388888888888888 (* x x)) x (* 0.16666666666666666 x)) x))
              double code(double x) {
              	return fma((-0.06388888888888888 * (x * x)), x, (0.16666666666666666 * x)) * x;
              }
              
              function code(x)
              	return Float64(fma(Float64(-0.06388888888888888 * Float64(x * x)), x, Float64(0.16666666666666666 * x)) * x)
              end
              
              code[x_] := N[(N[(N[(-0.06388888888888888 * N[(x * x), $MachinePrecision]), $MachinePrecision] * x + N[(0.16666666666666666 * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(-0.06388888888888888 \cdot \left(x \cdot x\right), x, 0.16666666666666666 \cdot x\right) \cdot x
              \end{array}
              
              Derivation
              1. Initial program 52.4%

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

                \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
              4. Step-by-step derivation
                1. *-commutativeN/A

                  \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
                2. unpow2N/A

                  \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
                3. associate-*r*N/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
                4. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
              5. Applied rewrites99.5%

                \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
              6. Step-by-step derivation
                1. Applied rewrites99.5%

                  \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
                2. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)} \]
                3. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot {x}^{2}} \]
                  2. unpow2N/A

                    \[\leadsto \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
                  3. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot x\right) \cdot x} \]
                  4. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right)} \cdot x \]
                  5. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right) \cdot x} \]
                  6. *-commutativeN/A

                    \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot x\right)} \cdot x \]
                  7. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot x\right)} \cdot x \]
                  8. +-commutativeN/A

                    \[\leadsto \left(\color{blue}{\left(\frac{-23}{360} \cdot {x}^{2} + \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                  9. *-commutativeN/A

                    \[\leadsto \left(\left(\color{blue}{{x}^{2} \cdot \frac{-23}{360}} + \frac{1}{6}\right) \cdot x\right) \cdot x \]
                  10. lower-fma.f64N/A

                    \[\leadsto \left(\color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-23}{360}, \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                  11. unpow2N/A

                    \[\leadsto \left(\mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-23}{360}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                  12. lower-*.f6498.9

                    \[\leadsto \left(\mathsf{fma}\left(\color{blue}{x \cdot x}, -0.06388888888888888, 0.16666666666666666\right) \cdot x\right) \cdot x \]
                4. Applied rewrites98.9%

                  \[\leadsto \color{blue}{\left(\mathsf{fma}\left(x \cdot x, -0.06388888888888888, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                5. Step-by-step derivation
                  1. Applied rewrites98.9%

                    \[\leadsto \mathsf{fma}\left(-0.06388888888888888 \cdot \left(x \cdot x\right), x, 0.16666666666666666 \cdot x\right) \cdot x \]
                  2. Add Preprocessing

                  Alternative 7: 99.3% accurate, 8.0× speedup?

                  \[\begin{array}{l} \\ \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(-0.06388888888888888 \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \end{array} \]
                  (FPCore (x)
                   :precision binary64
                   (* (fma x 0.16666666666666666 (* (* (* -0.06388888888888888 x) x) x)) x))
                  double code(double x) {
                  	return fma(x, 0.16666666666666666, (((-0.06388888888888888 * x) * x) * x)) * x;
                  }
                  
                  function code(x)
                  	return Float64(fma(x, 0.16666666666666666, Float64(Float64(Float64(-0.06388888888888888 * x) * x) * x)) * x)
                  end
                  
                  code[x_] := N[(N[(x * 0.16666666666666666 + N[(N[(N[(-0.06388888888888888 * x), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(-0.06388888888888888 \cdot x\right) \cdot x\right) \cdot x\right) \cdot x
                  \end{array}
                  
                  Derivation
                  1. Initial program 52.4%

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

                    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
                  4. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
                    2. unpow2N/A

                      \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
                    3. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
                    4. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
                  5. Applied rewrites99.5%

                    \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                  6. Step-by-step derivation
                    1. Applied rewrites99.5%

                      \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, -0.00023644179894179894, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right) \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
                    2. Taylor expanded in x around 0

                      \[\leadsto \mathsf{fma}\left(x, \frac{1}{6}, \left(\left(\frac{-23}{360} \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
                    3. Step-by-step derivation
                      1. Applied rewrites98.9%

                        \[\leadsto \mathsf{fma}\left(x, 0.16666666666666666, \left(\left(-0.06388888888888888 \cdot x\right) \cdot x\right) \cdot x\right) \cdot x \]
                      2. Add Preprocessing

                      Alternative 8: 99.3% accurate, 9.8× speedup?

                      \[\begin{array}{l} \\ \left(\mathsf{fma}\left(-0.06388888888888888, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x \end{array} \]
                      (FPCore (x)
                       :precision binary64
                       (* (* (fma -0.06388888888888888 (* x x) 0.16666666666666666) x) x))
                      double code(double x) {
                      	return (fma(-0.06388888888888888, (x * x), 0.16666666666666666) * x) * x;
                      }
                      
                      function code(x)
                      	return Float64(Float64(fma(-0.06388888888888888, Float64(x * x), 0.16666666666666666) * x) * x)
                      end
                      
                      code[x_] := N[(N[(N[(-0.06388888888888888 * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \left(\mathsf{fma}\left(-0.06388888888888888, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
                      \end{array}
                      
                      Derivation
                      1. Initial program 52.4%

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

                        \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)} \]
                      4. Step-by-step derivation
                        1. unpow2N/A

                          \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \]
                        2. associate-*l*N/A

                          \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right)} \]
                        3. *-commutativeN/A

                          \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right) \cdot x} \]
                        4. lower-*.f64N/A

                          \[\leadsto \color{blue}{\left(x \cdot \left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right)\right) \cdot x} \]
                        5. *-commutativeN/A

                          \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot x\right)} \cdot x \]
                        6. lower-*.f64N/A

                          \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + \frac{-23}{360} \cdot {x}^{2}\right) \cdot x\right)} \cdot x \]
                        7. +-commutativeN/A

                          \[\leadsto \left(\color{blue}{\left(\frac{-23}{360} \cdot {x}^{2} + \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                        8. lower-fma.f64N/A

                          \[\leadsto \left(\color{blue}{\mathsf{fma}\left(\frac{-23}{360}, {x}^{2}, \frac{1}{6}\right)} \cdot x\right) \cdot x \]
                        9. unpow2N/A

                          \[\leadsto \left(\mathsf{fma}\left(\frac{-23}{360}, \color{blue}{x \cdot x}, \frac{1}{6}\right) \cdot x\right) \cdot x \]
                        10. lower-*.f6498.9

                          \[\leadsto \left(\mathsf{fma}\left(-0.06388888888888888, \color{blue}{x \cdot x}, 0.16666666666666666\right) \cdot x\right) \cdot x \]
                      5. Applied rewrites98.9%

                        \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-0.06388888888888888, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                      6. Add Preprocessing

                      Alternative 9: 98.7% accurate, 19.5× speedup?

                      \[\begin{array}{l} \\ \left(0.16666666666666666 \cdot x\right) \cdot x \end{array} \]
                      (FPCore (x) :precision binary64 (* (* 0.16666666666666666 x) x))
                      double code(double x) {
                      	return (0.16666666666666666 * x) * x;
                      }
                      
                      real(8) function code(x)
                          real(8), intent (in) :: x
                          code = (0.16666666666666666d0 * x) * x
                      end function
                      
                      public static double code(double x) {
                      	return (0.16666666666666666 * x) * x;
                      }
                      
                      def code(x):
                      	return (0.16666666666666666 * x) * x
                      
                      function code(x)
                      	return Float64(Float64(0.16666666666666666 * x) * x)
                      end
                      
                      function tmp = code(x)
                      	tmp = (0.16666666666666666 * x) * x;
                      end
                      
                      code[x_] := N[(N[(0.16666666666666666 * x), $MachinePrecision] * x), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \left(0.16666666666666666 \cdot x\right) \cdot x
                      \end{array}
                      
                      Derivation
                      1. Initial program 52.4%

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

                        \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right)} \]
                      4. Step-by-step derivation
                        1. *-commutativeN/A

                          \[\leadsto \color{blue}{\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot {x}^{2}} \]
                        2. unpow2N/A

                          \[\leadsto \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
                        3. associate-*r*N/A

                          \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
                        4. lower-*.f64N/A

                          \[\leadsto \color{blue}{\left(\left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-143}{604800} \cdot {x}^{2} - \frac{11}{15120}\right) - \frac{23}{360}\right)\right) \cdot x\right) \cdot x} \]
                      5. Applied rewrites99.5%

                        \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.00023644179894179894, x \cdot x, -0.0007275132275132275\right), x \cdot x, -0.06388888888888888\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                      6. Taylor expanded in x around 0

                        \[\leadsto \left(\frac{1}{6} \cdot x\right) \cdot x \]
                      7. Step-by-step derivation
                        1. Applied rewrites98.1%

                          \[\leadsto \left(0.16666666666666666 \cdot x\right) \cdot x \]
                        2. Add Preprocessing

                        Alternative 10: 98.7% accurate, 19.5× speedup?

                        \[\begin{array}{l} \\ \left(x \cdot x\right) \cdot 0.16666666666666666 \end{array} \]
                        (FPCore (x) :precision binary64 (* (* x x) 0.16666666666666666))
                        double code(double x) {
                        	return (x * x) * 0.16666666666666666;
                        }
                        
                        real(8) function code(x)
                            real(8), intent (in) :: x
                            code = (x * x) * 0.16666666666666666d0
                        end function
                        
                        public static double code(double x) {
                        	return (x * x) * 0.16666666666666666;
                        }
                        
                        def code(x):
                        	return (x * x) * 0.16666666666666666
                        
                        function code(x)
                        	return Float64(Float64(x * x) * 0.16666666666666666)
                        end
                        
                        function tmp = code(x)
                        	tmp = (x * x) * 0.16666666666666666;
                        end
                        
                        code[x_] := N[(N[(x * x), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]
                        
                        \begin{array}{l}
                        
                        \\
                        \left(x \cdot x\right) \cdot 0.16666666666666666
                        \end{array}
                        
                        Derivation
                        1. Initial program 52.4%

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

                          \[\leadsto \color{blue}{\frac{1}{6} \cdot {x}^{2}} \]
                        4. Step-by-step derivation
                          1. *-commutativeN/A

                            \[\leadsto \color{blue}{{x}^{2} \cdot \frac{1}{6}} \]
                          2. lower-*.f64N/A

                            \[\leadsto \color{blue}{{x}^{2} \cdot \frac{1}{6}} \]
                          3. unpow2N/A

                            \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{6} \]
                          4. lower-*.f6498.1

                            \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot 0.16666666666666666 \]
                        5. Applied rewrites98.1%

                          \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot 0.16666666666666666} \]
                        6. Add Preprocessing

                        Developer Target 1: 98.7% accurate, 19.5× speedup?

                        \[\begin{array}{l} \\ 0.16666666666666666 \cdot \left(x \cdot x\right) \end{array} \]
                        (FPCore (x) :precision binary64 (* 0.16666666666666666 (* x x)))
                        double code(double x) {
                        	return 0.16666666666666666 * (x * x);
                        }
                        
                        real(8) function code(x)
                            real(8), intent (in) :: x
                            code = 0.16666666666666666d0 * (x * x)
                        end function
                        
                        public static double code(double x) {
                        	return 0.16666666666666666 * (x * x);
                        }
                        
                        def code(x):
                        	return 0.16666666666666666 * (x * x)
                        
                        function code(x)
                        	return Float64(0.16666666666666666 * Float64(x * x))
                        end
                        
                        function tmp = code(x)
                        	tmp = 0.16666666666666666 * (x * x);
                        end
                        
                        code[x_] := N[(0.16666666666666666 * N[(x * x), $MachinePrecision]), $MachinePrecision]
                        
                        \begin{array}{l}
                        
                        \\
                        0.16666666666666666 \cdot \left(x \cdot x\right)
                        \end{array}
                        

                        Reproduce

                        ?
                        herbie shell --seed 2024295 
                        (FPCore (x)
                          :name "ENA, Section 1.4, Exercise 4a"
                          :precision binary64
                          :pre (and (<= -1.0 x) (<= x 1.0))
                        
                          :alt
                          (! :herbie-platform default (* 1/6 (* x x)))
                        
                          (/ (- x (sin x)) (tan x)))