tanhf (example 3.4)

Percentage Accurate: 53.1% → 100.0%
Time: 9.2s
Alternatives: 10
Speedup: 2.0×

Specification

?
\[\begin{array}{l} \\ \frac{1 - \cos x}{\sin x} \end{array} \]
(FPCore (x) :precision binary64 (/ (- 1.0 (cos x)) (sin x)))
double code(double x) {
	return (1.0 - cos(x)) / sin(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 - cos(x)) / sin(x)
end function
public static double code(double x) {
	return (1.0 - Math.cos(x)) / Math.sin(x);
}
def code(x):
	return (1.0 - math.cos(x)) / math.sin(x)
function code(x)
	return Float64(Float64(1.0 - cos(x)) / sin(x))
end
function tmp = code(x)
	tmp = (1.0 - cos(x)) / sin(x);
end
code[x_] := N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[Sin[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1 - \cos x}{\sin 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: 53.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1 - \cos x}{\sin x} \end{array} \]
(FPCore (x) :precision binary64 (/ (- 1.0 (cos x)) (sin x)))
double code(double x) {
	return (1.0 - cos(x)) / sin(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 - cos(x)) / sin(x)
end function
public static double code(double x) {
	return (1.0 - Math.cos(x)) / Math.sin(x);
}
def code(x):
	return (1.0 - math.cos(x)) / math.sin(x)
function code(x)
	return Float64(Float64(1.0 - cos(x)) / sin(x))
end
function tmp = code(x)
	tmp = (1.0 - cos(x)) / sin(x);
end
code[x_] := N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[Sin[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1 - \cos x}{\sin x}
\end{array}

Alternative 1: 100.0% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \tan \left(x \cdot 0.5\right) \end{array} \]
(FPCore (x) :precision binary64 (tan (* x 0.5)))
double code(double x) {
	return tan((x * 0.5));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = tan((x * 0.5d0))
end function
public static double code(double x) {
	return Math.tan((x * 0.5));
}
def code(x):
	return math.tan((x * 0.5))
function code(x)
	return tan(Float64(x * 0.5))
end
function tmp = code(x)
	tmp = tan((x * 0.5));
end
code[x_] := N[Tan[N[(x * 0.5), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\tan \left(x \cdot 0.5\right)
\end{array}
Derivation
  1. Initial program 54.3%

    \[\frac{1 - \cos x}{\sin x} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{1 - \cos x}{\sin x}} \]
    2. lift--.f64N/A

      \[\leadsto \frac{\color{blue}{1 - \cos x}}{\sin x} \]
    3. lift-cos.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\cos x}}{\sin x} \]
    4. lift-sin.f64N/A

      \[\leadsto \frac{1 - \cos x}{\color{blue}{\sin x}} \]
    5. hang-p0-tanN/A

      \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right)} \]
    6. lower-tan.f64N/A

      \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right)} \]
    7. div-invN/A

      \[\leadsto \tan \color{blue}{\left(x \cdot \frac{1}{2}\right)} \]
    8. metadata-evalN/A

      \[\leadsto \tan \left(x \cdot \color{blue}{\frac{1}{2}}\right) \]
    9. lower-*.f64100.0

      \[\leadsto \tan \color{blue}{\left(x \cdot 0.5\right)} \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{\tan \left(x \cdot 0.5\right)} \]
  5. Add Preprocessing

Alternative 2: 52.7% accurate, 3.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), \left(x \cdot x\right) \cdot \left(x \cdot x\right), \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 3.2)
   (*
    x
    (fma
     (fma x (* x 0.00042162698412698415) 0.004166666666666667)
     (* (* x x) (* x x))
     (fma x (* x 0.041666666666666664) 0.5)))
   1.0))
double code(double x) {
	double tmp;
	if (x <= 3.2) {
		tmp = x * fma(fma(x, (x * 0.00042162698412698415), 0.004166666666666667), ((x * x) * (x * x)), fma(x, (x * 0.041666666666666664), 0.5));
	} else {
		tmp = 1.0;
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 3.2)
		tmp = Float64(x * fma(fma(x, Float64(x * 0.00042162698412698415), 0.004166666666666667), Float64(Float64(x * x) * Float64(x * x)), fma(x, Float64(x * 0.041666666666666664), 0.5)));
	else
		tmp = 1.0;
	end
	return tmp
end
code[x_] := If[LessEqual[x, 3.2], N[(x * N[(N[(x * N[(x * 0.00042162698412698415), $MachinePrecision] + 0.004166666666666667), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision] + N[(x * N[(x * 0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 3.2:\\
\;\;\;\;x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), \left(x \cdot x\right) \cdot \left(x \cdot x\right), \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 3.2000000000000002

    1. Initial program 38.3%

      \[\frac{1 - \cos x}{\sin x} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
    4. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
      2. +-commutativeN/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right)} \]
      3. lower-fma.f64N/A

        \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right)} \]
      4. unpow2N/A

        \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
      5. lower-*.f64N/A

        \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
      6. +-commutativeN/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right) + \frac{1}{24}}, \frac{1}{2}\right) \]
      7. lower-fma.f64N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
      8. unpow2N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      9. lower-*.f64N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      10. +-commutativeN/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{17}{40320} \cdot {x}^{2} + \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      11. unpow2N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{17}{40320} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      12. associate-*r*N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{17}{40320} \cdot x\right) \cdot x} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      13. *-commutativeN/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{17}{40320} \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      14. lower-fma.f64N/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{17}{40320} \cdot x, \frac{1}{240}\right)}, \frac{1}{24}\right), \frac{1}{2}\right) \]
      15. *-commutativeN/A

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{17}{40320}}, \frac{1}{240}\right), \frac{1}{24}\right), \frac{1}{2}\right) \]
      16. lower-*.f6466.6

        \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.00042162698412698415}, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right) \]
    5. Applied rewrites66.6%

      \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites66.6%

        \[\leadsto x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), \color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot x\right)}, \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)\right) \]

      if 3.2000000000000002 < x

      1. Initial program 98.4%

        \[\frac{1 - \cos x}{\sin x} \]
      2. Add Preprocessing
      3. Applied rewrites10.4%

        \[\leadsto \color{blue}{{1}^{-0.5}} \]
      4. Step-by-step derivation
        1. lift-pow.f64N/A

          \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
        2. pow-base-110.4

          \[\leadsto \color{blue}{1} \]
      5. Applied rewrites10.4%

        \[\leadsto \color{blue}{1} \]
    7. Recombined 2 regimes into one program.
    8. Add Preprocessing

    Alternative 3: 52.7% accurate, 4.3× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), x \cdot \left(x \cdot x\right), x \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (<= x 3.2)
       (fma
        (fma
         x
         (* x (fma x (* x 0.00042162698412698415) 0.004166666666666667))
         0.041666666666666664)
        (* x (* x x))
        (* x 0.5))
       1.0))
    double code(double x) {
    	double tmp;
    	if (x <= 3.2) {
    		tmp = fma(fma(x, (x * fma(x, (x * 0.00042162698412698415), 0.004166666666666667)), 0.041666666666666664), (x * (x * x)), (x * 0.5));
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    function code(x)
    	tmp = 0.0
    	if (x <= 3.2)
    		tmp = fma(fma(x, Float64(x * fma(x, Float64(x * 0.00042162698412698415), 0.004166666666666667)), 0.041666666666666664), Float64(x * Float64(x * x)), Float64(x * 0.5));
    	else
    		tmp = 1.0;
    	end
    	return tmp
    end
    
    code[x_] := If[LessEqual[x, 3.2], N[(N[(x * N[(x * N[(x * N[(x * 0.00042162698412698415), $MachinePrecision] + 0.004166666666666667), $MachinePrecision]), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] + N[(x * 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;x \leq 3.2:\\
    \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), x \cdot \left(x \cdot x\right), x \cdot 0.5\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;1\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 3.2000000000000002

      1. Initial program 38.3%

        \[\frac{1 - \cos x}{\sin x} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
      4. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
        2. +-commutativeN/A

          \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right)} \]
        3. lower-fma.f64N/A

          \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right)} \]
        4. unpow2N/A

          \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
        5. lower-*.f64N/A

          \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
        6. +-commutativeN/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right) + \frac{1}{24}}, \frac{1}{2}\right) \]
        7. lower-fma.f64N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
        8. unpow2N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        9. lower-*.f64N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        10. +-commutativeN/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{17}{40320} \cdot {x}^{2} + \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        11. unpow2N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{17}{40320} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        12. associate-*r*N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{17}{40320} \cdot x\right) \cdot x} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        13. *-commutativeN/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{17}{40320} \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        14. lower-fma.f64N/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{17}{40320} \cdot x, \frac{1}{240}\right)}, \frac{1}{24}\right), \frac{1}{2}\right) \]
        15. *-commutativeN/A

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{17}{40320}}, \frac{1}{240}\right), \frac{1}{24}\right), \frac{1}{2}\right) \]
        16. lower-*.f6466.6

          \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.00042162698412698415}, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right) \]
      5. Applied rewrites66.6%

        \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites66.6%

          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), \color{blue}{x \cdot \left(x \cdot x\right)}, x \cdot 0.5\right) \]

        if 3.2000000000000002 < x

        1. Initial program 98.4%

          \[\frac{1 - \cos x}{\sin x} \]
        2. Add Preprocessing
        3. Applied rewrites10.4%

          \[\leadsto \color{blue}{{1}^{-0.5}} \]
        4. Step-by-step derivation
          1. lift-pow.f64N/A

            \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
          2. pow-base-110.4

            \[\leadsto \color{blue}{1} \]
        5. Applied rewrites10.4%

          \[\leadsto \color{blue}{1} \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 4: 52.7% accurate, 4.8× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (if (<= x 3.2)
         (*
          x
          (fma
           x
           (*
            x
            (fma
             x
             (* x (fma x (* x 0.00042162698412698415) 0.004166666666666667))
             0.041666666666666664))
           0.5))
         1.0))
      double code(double x) {
      	double tmp;
      	if (x <= 3.2) {
      		tmp = x * fma(x, (x * fma(x, (x * fma(x, (x * 0.00042162698412698415), 0.004166666666666667)), 0.041666666666666664)), 0.5);
      	} else {
      		tmp = 1.0;
      	}
      	return tmp;
      }
      
      function code(x)
      	tmp = 0.0
      	if (x <= 3.2)
      		tmp = Float64(x * fma(x, Float64(x * fma(x, Float64(x * fma(x, Float64(x * 0.00042162698412698415), 0.004166666666666667)), 0.041666666666666664)), 0.5));
      	else
      		tmp = 1.0;
      	end
      	return tmp
      end
      
      code[x_] := If[LessEqual[x, 3.2], N[(x * N[(x * N[(x * N[(x * N[(x * N[(x * N[(x * 0.00042162698412698415), $MachinePrecision] + 0.004166666666666667), $MachinePrecision]), $MachinePrecision] + 0.041666666666666664), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;x \leq 3.2:\\
      \;\;\;\;x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;1\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if x < 3.2000000000000002

        1. Initial program 38.3%

          \[\frac{1 - \cos x}{\sin x} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
        4. Step-by-step derivation
          1. lower-*.f64N/A

            \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
          2. +-commutativeN/A

            \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right)} \]
          3. lower-fma.f64N/A

            \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right)} \]
          4. unpow2N/A

            \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
          5. lower-*.f64N/A

            \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
          6. +-commutativeN/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right) + \frac{1}{24}}, \frac{1}{2}\right) \]
          7. lower-fma.f64N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
          8. unpow2N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          9. lower-*.f64N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          10. +-commutativeN/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{17}{40320} \cdot {x}^{2} + \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          11. unpow2N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{17}{40320} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          12. associate-*r*N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{17}{40320} \cdot x\right) \cdot x} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          13. *-commutativeN/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{17}{40320} \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          14. lower-fma.f64N/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{17}{40320} \cdot x, \frac{1}{240}\right)}, \frac{1}{24}\right), \frac{1}{2}\right) \]
          15. *-commutativeN/A

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{17}{40320}}, \frac{1}{240}\right), \frac{1}{24}\right), \frac{1}{2}\right) \]
          16. lower-*.f6466.6

            \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.00042162698412698415}, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right) \]
        5. Applied rewrites66.6%

          \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)} \]
        6. Step-by-step derivation
          1. Applied rewrites66.6%

            \[\leadsto \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right) \cdot \color{blue}{x} \]

          if 3.2000000000000002 < x

          1. Initial program 98.4%

            \[\frac{1 - \cos x}{\sin x} \]
          2. Add Preprocessing
          3. Applied rewrites10.4%

            \[\leadsto \color{blue}{{1}^{-0.5}} \]
          4. Step-by-step derivation
            1. lift-pow.f64N/A

              \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
            2. pow-base-110.4

              \[\leadsto \color{blue}{1} \]
          5. Applied rewrites10.4%

            \[\leadsto \color{blue}{1} \]
        7. Recombined 2 regimes into one program.
        8. Final simplification51.7%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
        9. Add Preprocessing

        Alternative 5: 52.7% accurate, 4.8× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 3.2)
           (*
            x
            (fma
             (* x x)
             (fma
              (* x x)
              (fma x (* x 0.00042162698412698415) 0.004166666666666667)
              0.041666666666666664)
             0.5))
           1.0))
        double code(double x) {
        	double tmp;
        	if (x <= 3.2) {
        		tmp = x * fma((x * x), fma((x * x), fma(x, (x * 0.00042162698412698415), 0.004166666666666667), 0.041666666666666664), 0.5);
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= 3.2)
        		tmp = Float64(x * fma(Float64(x * x), fma(Float64(x * x), fma(x, Float64(x * 0.00042162698412698415), 0.004166666666666667), 0.041666666666666664), 0.5));
        	else
        		tmp = 1.0;
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, 3.2], N[(x * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * 0.00042162698412698415), $MachinePrecision] + 0.004166666666666667), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 3.2:\\
        \;\;\;\;x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 3.2000000000000002

          1. Initial program 38.3%

            \[\frac{1 - \cos x}{\sin x} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
          4. Step-by-step derivation
            1. lower-*.f64N/A

              \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right)\right)} \]
            2. +-commutativeN/A

              \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right)} \]
            3. lower-fma.f64N/A

              \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right)} \]
            4. unpow2N/A

              \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
            5. lower-*.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + {x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right), \frac{1}{2}\right) \]
            6. +-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}\right) + \frac{1}{24}}, \frac{1}{2}\right) \]
            7. lower-fma.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
            8. unpow2N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            9. lower-*.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{240} + \frac{17}{40320} \cdot {x}^{2}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            10. +-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{17}{40320} \cdot {x}^{2} + \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            11. unpow2N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{17}{40320} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            12. associate-*r*N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{17}{40320} \cdot x\right) \cdot x} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            13. *-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{17}{40320} \cdot x\right)} + \frac{1}{240}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            14. lower-fma.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{17}{40320} \cdot x, \frac{1}{240}\right)}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            15. *-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{17}{40320}}, \frac{1}{240}\right), \frac{1}{24}\right), \frac{1}{2}\right) \]
            16. lower-*.f6466.6

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.00042162698412698415}, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right) \]
          5. Applied rewrites66.6%

            \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.00042162698412698415, 0.004166666666666667\right), 0.041666666666666664\right), 0.5\right)} \]

          if 3.2000000000000002 < x

          1. Initial program 98.4%

            \[\frac{1 - \cos x}{\sin x} \]
          2. Add Preprocessing
          3. Applied rewrites10.4%

            \[\leadsto \color{blue}{{1}^{-0.5}} \]
          4. Step-by-step derivation
            1. lift-pow.f64N/A

              \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
            2. pow-base-110.4

              \[\leadsto \color{blue}{1} \]
          5. Applied rewrites10.4%

            \[\leadsto \color{blue}{1} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 6: 52.7% accurate, 5.5× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), x \cdot \left(x \cdot x\right), x \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 3.2)
           (fma
            (fma x (* x 0.004166666666666667) 0.041666666666666664)
            (* x (* x x))
            (* x 0.5))
           1.0))
        double code(double x) {
        	double tmp;
        	if (x <= 3.2) {
        		tmp = fma(fma(x, (x * 0.004166666666666667), 0.041666666666666664), (x * (x * x)), (x * 0.5));
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= 3.2)
        		tmp = fma(fma(x, Float64(x * 0.004166666666666667), 0.041666666666666664), Float64(x * Float64(x * x)), Float64(x * 0.5));
        	else
        		tmp = 1.0;
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, 3.2], N[(N[(x * N[(x * 0.004166666666666667), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] + N[(x * 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 3.2:\\
        \;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), x \cdot \left(x \cdot x\right), x \cdot 0.5\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 3.2000000000000002

          1. Initial program 38.3%

            \[\frac{1 - \cos x}{\sin x} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right)\right)} \]
          4. Step-by-step derivation
            1. lower-*.f64N/A

              \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right)\right)} \]
            2. +-commutativeN/A

              \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right) + \frac{1}{2}\right)} \]
            3. lower-fma.f64N/A

              \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right)} \]
            4. unpow2N/A

              \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right) \]
            5. lower-*.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right) \]
            6. +-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{1}{240} \cdot {x}^{2} + \frac{1}{24}}, \frac{1}{2}\right) \]
            7. unpow2N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \frac{1}{240} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{24}, \frac{1}{2}\right) \]
            8. associate-*r*N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{1}{240} \cdot x\right) \cdot x} + \frac{1}{24}, \frac{1}{2}\right) \]
            9. *-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{1}{240} \cdot x\right)} + \frac{1}{24}, \frac{1}{2}\right) \]
            10. lower-fma.f64N/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{240} \cdot x, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
            11. *-commutativeN/A

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
            12. lower-*.f6466.6

              \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.004166666666666667}, 0.041666666666666664\right), 0.5\right) \]
          5. Applied rewrites66.6%

            \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), 0.5\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites66.6%

              \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), \color{blue}{x \cdot \left(x \cdot x\right)}, x \cdot 0.5\right) \]

            if 3.2000000000000002 < x

            1. Initial program 98.4%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Applied rewrites10.4%

              \[\leadsto \color{blue}{{1}^{-0.5}} \]
            4. Step-by-step derivation
              1. lift-pow.f64N/A

                \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
              2. pow-base-110.4

                \[\leadsto \color{blue}{1} \]
            5. Applied rewrites10.4%

              \[\leadsto \color{blue}{1} \]
          7. Recombined 2 regimes into one program.
          8. Add Preprocessing

          Alternative 7: 52.7% accurate, 6.3× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
          (FPCore (x)
           :precision binary64
           (if (<= x 3.2)
             (*
              x
              (fma (* x x) (fma x (* x 0.004166666666666667) 0.041666666666666664) 0.5))
             1.0))
          double code(double x) {
          	double tmp;
          	if (x <= 3.2) {
          		tmp = x * fma((x * x), fma(x, (x * 0.004166666666666667), 0.041666666666666664), 0.5);
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          function code(x)
          	tmp = 0.0
          	if (x <= 3.2)
          		tmp = Float64(x * fma(Float64(x * x), fma(x, Float64(x * 0.004166666666666667), 0.041666666666666664), 0.5));
          	else
          		tmp = 1.0;
          	end
          	return tmp
          end
          
          code[x_] := If[LessEqual[x, 3.2], N[(x * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * 0.004166666666666667), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;x \leq 3.2:\\
          \;\;\;\;x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), 0.5\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < 3.2000000000000002

            1. Initial program 38.3%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Taylor expanded in x around 0

              \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right)\right)} \]
            4. Step-by-step derivation
              1. lower-*.f64N/A

                \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right)\right)} \]
              2. +-commutativeN/A

                \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{240} \cdot {x}^{2}\right) + \frac{1}{2}\right)} \]
              3. lower-fma.f64N/A

                \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right)} \]
              4. unpow2N/A

                \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right) \]
              5. lower-*.f64N/A

                \[\leadsto x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{240} \cdot {x}^{2}, \frac{1}{2}\right) \]
              6. +-commutativeN/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{1}{240} \cdot {x}^{2} + \frac{1}{24}}, \frac{1}{2}\right) \]
              7. unpow2N/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \frac{1}{240} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{24}, \frac{1}{2}\right) \]
              8. associate-*r*N/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\left(\frac{1}{240} \cdot x\right) \cdot x} + \frac{1}{24}, \frac{1}{2}\right) \]
              9. *-commutativeN/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(\frac{1}{240} \cdot x\right)} + \frac{1}{24}, \frac{1}{2}\right) \]
              10. lower-fma.f64N/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{240} \cdot x, \frac{1}{24}\right)}, \frac{1}{2}\right) \]
              11. *-commutativeN/A

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{1}{240}}, \frac{1}{24}\right), \frac{1}{2}\right) \]
              12. lower-*.f6466.6

                \[\leadsto x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.004166666666666667}, 0.041666666666666664\right), 0.5\right) \]
            5. Applied rewrites66.6%

              \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.004166666666666667, 0.041666666666666664\right), 0.5\right)} \]

            if 3.2000000000000002 < x

            1. Initial program 98.4%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Applied rewrites10.4%

              \[\leadsto \color{blue}{{1}^{-0.5}} \]
            4. Step-by-step derivation
              1. lift-pow.f64N/A

                \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
              2. pow-base-110.4

                \[\leadsto \color{blue}{1} \]
            5. Applied rewrites10.4%

              \[\leadsto \color{blue}{1} \]
          3. Recombined 2 regimes into one program.
          4. Add Preprocessing

          Alternative 8: 52.6% accurate, 9.3× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.2:\\ \;\;\;\;x \cdot \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
          (FPCore (x)
           :precision binary64
           (if (<= x 3.2) (* x (fma x (* x 0.041666666666666664) 0.5)) 1.0))
          double code(double x) {
          	double tmp;
          	if (x <= 3.2) {
          		tmp = x * fma(x, (x * 0.041666666666666664), 0.5);
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          function code(x)
          	tmp = 0.0
          	if (x <= 3.2)
          		tmp = Float64(x * fma(x, Float64(x * 0.041666666666666664), 0.5));
          	else
          		tmp = 1.0;
          	end
          	return tmp
          end
          
          code[x_] := If[LessEqual[x, 3.2], N[(x * N[(x * N[(x * 0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], 1.0]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;x \leq 3.2:\\
          \;\;\;\;x \cdot \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < 3.2000000000000002

            1. Initial program 38.3%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Taylor expanded in x around 0

              \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)} \]
            4. Step-by-step derivation
              1. lower-*.f64N/A

                \[\leadsto \color{blue}{x \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)} \]
              2. +-commutativeN/A

                \[\leadsto x \cdot \color{blue}{\left(\frac{1}{24} \cdot {x}^{2} + \frac{1}{2}\right)} \]
              3. unpow2N/A

                \[\leadsto x \cdot \left(\frac{1}{24} \cdot \color{blue}{\left(x \cdot x\right)} + \frac{1}{2}\right) \]
              4. associate-*r*N/A

                \[\leadsto x \cdot \left(\color{blue}{\left(\frac{1}{24} \cdot x\right) \cdot x} + \frac{1}{2}\right) \]
              5. *-commutativeN/A

                \[\leadsto x \cdot \left(\color{blue}{x \cdot \left(\frac{1}{24} \cdot x\right)} + \frac{1}{2}\right) \]
              6. lower-fma.f64N/A

                \[\leadsto x \cdot \color{blue}{\mathsf{fma}\left(x, \frac{1}{24} \cdot x, \frac{1}{2}\right)} \]
              7. *-commutativeN/A

                \[\leadsto x \cdot \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{1}{24}}, \frac{1}{2}\right) \]
              8. lower-*.f6466.6

                \[\leadsto x \cdot \mathsf{fma}\left(x, \color{blue}{x \cdot 0.041666666666666664}, 0.5\right) \]
            5. Applied rewrites66.6%

              \[\leadsto \color{blue}{x \cdot \mathsf{fma}\left(x, x \cdot 0.041666666666666664, 0.5\right)} \]

            if 3.2000000000000002 < x

            1. Initial program 98.4%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Applied rewrites10.4%

              \[\leadsto \color{blue}{{1}^{-0.5}} \]
            4. Step-by-step derivation
              1. lift-pow.f64N/A

                \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
              2. pow-base-110.4

                \[\leadsto \color{blue}{1} \]
            5. Applied rewrites10.4%

              \[\leadsto \color{blue}{1} \]
          3. Recombined 2 regimes into one program.
          4. Add Preprocessing

          Alternative 9: 52.6% accurate, 17.9× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.4:\\ \;\;\;\;x \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
          (FPCore (x) :precision binary64 (if (<= x 1.4) (* x 0.5) 1.0))
          double code(double x) {
          	double tmp;
          	if (x <= 1.4) {
          		tmp = x * 0.5;
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              real(8) :: tmp
              if (x <= 1.4d0) then
                  tmp = x * 0.5d0
              else
                  tmp = 1.0d0
              end if
              code = tmp
          end function
          
          public static double code(double x) {
          	double tmp;
          	if (x <= 1.4) {
          		tmp = x * 0.5;
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          def code(x):
          	tmp = 0
          	if x <= 1.4:
          		tmp = x * 0.5
          	else:
          		tmp = 1.0
          	return tmp
          
          function code(x)
          	tmp = 0.0
          	if (x <= 1.4)
          		tmp = Float64(x * 0.5);
          	else
          		tmp = 1.0;
          	end
          	return tmp
          end
          
          function tmp_2 = code(x)
          	tmp = 0.0;
          	if (x <= 1.4)
          		tmp = x * 0.5;
          	else
          		tmp = 1.0;
          	end
          	tmp_2 = tmp;
          end
          
          code[x_] := If[LessEqual[x, 1.4], N[(x * 0.5), $MachinePrecision], 1.0]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;x \leq 1.4:\\
          \;\;\;\;x \cdot 0.5\\
          
          \mathbf{else}:\\
          \;\;\;\;1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < 1.3999999999999999

            1. Initial program 38.0%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Taylor expanded in x around 0

              \[\leadsto \color{blue}{\frac{1}{2} \cdot x} \]
            4. Step-by-step derivation
              1. lower-*.f6466.8

                \[\leadsto \color{blue}{0.5 \cdot x} \]
            5. Applied rewrites66.8%

              \[\leadsto \color{blue}{0.5 \cdot x} \]

            if 1.3999999999999999 < x

            1. Initial program 98.4%

              \[\frac{1 - \cos x}{\sin x} \]
            2. Add Preprocessing
            3. Applied rewrites10.5%

              \[\leadsto \color{blue}{{1}^{-0.5}} \]
            4. Step-by-step derivation
              1. lift-pow.f64N/A

                \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
              2. pow-base-110.5

                \[\leadsto \color{blue}{1} \]
            5. Applied rewrites10.5%

              \[\leadsto \color{blue}{1} \]
          3. Recombined 2 regimes into one program.
          4. Final simplification51.7%

            \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.4:\\ \;\;\;\;x \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
          5. Add Preprocessing

          Alternative 10: 7.0% accurate, 215.0× speedup?

          \[\begin{array}{l} \\ 1 \end{array} \]
          (FPCore (x) :precision binary64 1.0)
          double code(double x) {
          	return 1.0;
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = 1.0d0
          end function
          
          public static double code(double x) {
          	return 1.0;
          }
          
          def code(x):
          	return 1.0
          
          function code(x)
          	return 1.0
          end
          
          function tmp = code(x)
          	tmp = 1.0;
          end
          
          code[x_] := 1.0
          
          \begin{array}{l}
          
          \\
          1
          \end{array}
          
          Derivation
          1. Initial program 54.3%

            \[\frac{1 - \cos x}{\sin x} \]
          2. Add Preprocessing
          3. Applied rewrites6.6%

            \[\leadsto \color{blue}{{1}^{-0.5}} \]
          4. Step-by-step derivation
            1. lift-pow.f64N/A

              \[\leadsto \color{blue}{{1}^{\frac{-1}{2}}} \]
            2. pow-base-16.6

              \[\leadsto \color{blue}{1} \]
          5. Applied rewrites6.6%

            \[\leadsto \color{blue}{1} \]
          6. Add Preprocessing

          Developer Target 1: 100.0% accurate, 1.9× speedup?

          \[\begin{array}{l} \\ \tan \left(\frac{x}{2}\right) \end{array} \]
          (FPCore (x) :precision binary64 (tan (/ x 2.0)))
          double code(double x) {
          	return tan((x / 2.0));
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = tan((x / 2.0d0))
          end function
          
          public static double code(double x) {
          	return Math.tan((x / 2.0));
          }
          
          def code(x):
          	return math.tan((x / 2.0))
          
          function code(x)
          	return tan(Float64(x / 2.0))
          end
          
          function tmp = code(x)
          	tmp = tan((x / 2.0));
          end
          
          code[x_] := N[Tan[N[(x / 2.0), $MachinePrecision]], $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \tan \left(\frac{x}{2}\right)
          \end{array}
          

          Reproduce

          ?
          herbie shell --seed 2024238 
          (FPCore (x)
            :name "tanhf (example 3.4)"
            :precision binary64
          
            :alt
            (! :herbie-platform default (tan (/ x 2)))
          
            (/ (- 1.0 (cos x)) (sin x)))