cos2 (problem 3.4.1)

Percentage Accurate: 51.4% → 99.8%
Time: 7.6s
Alternatives: 8
Speedup: 17.1×

Specification

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

\\
\frac{1 - \cos x}{x \cdot 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 8 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: 51.4% accurate, 1.0× speedup?

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

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

Alternative 1: 99.8% accurate, 0.5× speedup?

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

\\
\frac{\tan \left(\frac{x}{2}\right)}{x} \cdot \frac{\sin x}{x}
\end{array}
Derivation
  1. Initial program 51.1%

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

      \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
    2. flip--N/A

      \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
    3. lower-/.f64N/A

      \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
    4. metadata-evalN/A

      \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
    5. lift-cos.f64N/A

      \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
    6. lift-cos.f64N/A

      \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
    7. 1-sub-cosN/A

      \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
    8. pow2N/A

      \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
    9. lower-pow.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
    10. lower-sin.f64N/A

      \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
    11. +-commutativeN/A

      \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
    12. lower-+.f6475.8

      \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
  4. Applied rewrites75.8%

    \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
  5. Step-by-step derivation
    1. lift-/.f64N/A

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

      \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
    3. associate-/l/N/A

      \[\leadsto \color{blue}{\frac{{\sin x}^{2}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)}} \]
    4. lift-pow.f64N/A

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

      \[\leadsto \frac{\color{blue}{\sin x \cdot \sin x}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)} \]
    6. times-fracN/A

      \[\leadsto \color{blue}{\frac{\sin x}{\cos x + 1} \cdot \frac{\sin x}{x \cdot x}} \]
    7. lower-*.f64N/A

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

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

      \[\leadsto \frac{\sin x}{\color{blue}{\cos x + 1}} \cdot \frac{\sin x}{x \cdot x} \]
    10. +-commutativeN/A

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

      \[\leadsto \frac{\sin x}{1 + \color{blue}{\cos x}} \cdot \frac{\sin x}{x \cdot x} \]
    12. hang-0p-tanN/A

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

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

      \[\leadsto \tan \color{blue}{\left(\frac{x}{2}\right)} \cdot \frac{\sin x}{x \cdot x} \]
    15. lower-/.f6476.1

      \[\leadsto \tan \left(\frac{x}{2}\right) \cdot \color{blue}{\frac{\sin x}{x \cdot x}} \]
  6. Applied rewrites76.1%

    \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right) \cdot \frac{\sin x}{x \cdot x}} \]
  7. Step-by-step derivation
    1. lift-*.f64N/A

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

      \[\leadsto \tan \left(\frac{x}{2}\right) \cdot \color{blue}{\frac{\sin x}{x \cdot x}} \]
    3. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{\tan \left(\frac{x}{2}\right) \cdot \sin x}{x \cdot x}} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{\tan \left(\frac{x}{2}\right) \cdot \sin x}{\color{blue}{x \cdot x}} \]
    5. times-fracN/A

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

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

      \[\leadsto \color{blue}{\frac{\tan \left(\frac{x}{2}\right)}{x}} \cdot \frac{\sin x}{x} \]
    8. lower-/.f6499.8

      \[\leadsto \frac{\tan \left(\frac{x}{2}\right)}{x} \cdot \color{blue}{\frac{\sin x}{x}} \]
  8. Applied rewrites99.8%

    \[\leadsto \color{blue}{\frac{\tan \left(\frac{x}{2}\right)}{x} \cdot \frac{\sin x}{x}} \]
  9. Add Preprocessing

Alternative 2: 74.7% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.0002:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\tan \left(\frac{x}{2}\right) \cdot \frac{\sin x}{x \cdot x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 0.0002)
   (fma (* x x) -0.041666666666666664 0.5)
   (* (tan (/ x 2.0)) (/ (sin x) (* x x)))))
double code(double x) {
	double tmp;
	if (x <= 0.0002) {
		tmp = fma((x * x), -0.041666666666666664, 0.5);
	} else {
		tmp = tan((x / 2.0)) * (sin(x) / (x * x));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 0.0002)
		tmp = fma(Float64(x * x), -0.041666666666666664, 0.5);
	else
		tmp = Float64(tan(Float64(x / 2.0)) * Float64(sin(x) / Float64(x * x)));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 0.0002], N[(N[(x * x), $MachinePrecision] * -0.041666666666666664 + 0.5), $MachinePrecision], N[(N[Tan[N[(x / 2.0), $MachinePrecision]], $MachinePrecision] * N[(N[Sin[x], $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.0002:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\tan \left(\frac{x}{2}\right) \cdot \frac{\sin x}{x \cdot x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 2.0000000000000001e-4

    1. Initial program 34.7%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \frac{-1}{24} \cdot {x}^{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

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

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

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{24}, \frac{1}{2}\right) \]
      5. lower-*.f6467.0

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.041666666666666664, 0.5\right) \]
    5. Applied rewrites67.0%

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

    if 2.0000000000000001e-4 < x

    1. Initial program 99.3%

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

        \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
      2. flip--N/A

        \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
      3. lower-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
      4. metadata-evalN/A

        \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
      5. lift-cos.f64N/A

        \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
      6. lift-cos.f64N/A

        \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
      7. 1-sub-cosN/A

        \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
      8. pow2N/A

        \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
      9. lower-pow.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
      10. lower-sin.f64N/A

        \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
      11. +-commutativeN/A

        \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
      12. lower-+.f6499.2

        \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
    4. Applied rewrites99.2%

      \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

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

        \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
      3. associate-/l/N/A

        \[\leadsto \color{blue}{\frac{{\sin x}^{2}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)}} \]
      4. lift-pow.f64N/A

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

        \[\leadsto \frac{\color{blue}{\sin x \cdot \sin x}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)} \]
      6. times-fracN/A

        \[\leadsto \color{blue}{\frac{\sin x}{\cos x + 1} \cdot \frac{\sin x}{x \cdot x}} \]
      7. lower-*.f64N/A

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

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

        \[\leadsto \frac{\sin x}{\color{blue}{\cos x + 1}} \cdot \frac{\sin x}{x \cdot x} \]
      10. +-commutativeN/A

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

        \[\leadsto \frac{\sin x}{1 + \color{blue}{\cos x}} \cdot \frac{\sin x}{x \cdot x} \]
      12. hang-0p-tanN/A

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

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

        \[\leadsto \tan \color{blue}{\left(\frac{x}{2}\right)} \cdot \frac{\sin x}{x \cdot x} \]
      15. lower-/.f6499.6

        \[\leadsto \tan \left(\frac{x}{2}\right) \cdot \color{blue}{\frac{\sin x}{x \cdot x}} \]
    6. Applied rewrites99.6%

      \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right) \cdot \frac{\sin x}{x \cdot x}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 74.8% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.0056:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{1 - \cos x}{x}}{x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 0.0056)
   (fma (* x x) -0.041666666666666664 0.5)
   (/ (/ (- 1.0 (cos x)) x) x)))
double code(double x) {
	double tmp;
	if (x <= 0.0056) {
		tmp = fma((x * x), -0.041666666666666664, 0.5);
	} else {
		tmp = ((1.0 - cos(x)) / x) / x;
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 0.0056)
		tmp = fma(Float64(x * x), -0.041666666666666664, 0.5);
	else
		tmp = Float64(Float64(Float64(1.0 - cos(x)) / x) / x);
	end
	return tmp
end
code[x_] := If[LessEqual[x, 0.0056], N[(N[(x * x), $MachinePrecision] * -0.041666666666666664 + 0.5), $MachinePrecision], N[(N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / x), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.0056:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{1 - \cos x}{x}}{x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.00559999999999999994

    1. Initial program 34.7%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \frac{-1}{24} \cdot {x}^{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

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

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

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{24}, \frac{1}{2}\right) \]
      5. lower-*.f6467.0

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.041666666666666664, 0.5\right) \]
    5. Applied rewrites67.0%

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

    if 0.00559999999999999994 < x

    1. Initial program 99.3%

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

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

        \[\leadsto \frac{1 - \cos x}{\color{blue}{x \cdot x}} \]
      3. associate-/r*N/A

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

        \[\leadsto \color{blue}{\frac{\frac{1 - \cos x}{x}}{x}} \]
      5. lower-/.f6499.3

        \[\leadsto \frac{\color{blue}{\frac{1 - \cos x}{x}}}{x} \]
    4. Applied rewrites99.3%

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

Alternative 4: 74.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.0056:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1 - \cos x}{x \cdot x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 0.0056)
   (fma (* x x) -0.041666666666666664 0.5)
   (/ (- 1.0 (cos x)) (* x x))))
double code(double x) {
	double tmp;
	if (x <= 0.0056) {
		tmp = fma((x * x), -0.041666666666666664, 0.5);
	} else {
		tmp = (1.0 - cos(x)) / (x * x);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 0.0056)
		tmp = fma(Float64(x * x), -0.041666666666666664, 0.5);
	else
		tmp = Float64(Float64(1.0 - cos(x)) / Float64(x * x));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 0.0056], N[(N[(x * x), $MachinePrecision] * -0.041666666666666664 + 0.5), $MachinePrecision], N[(N[(1.0 - N[Cos[x], $MachinePrecision]), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.0056:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, -0.041666666666666664, 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{1 - \cos x}{x \cdot x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.00559999999999999994

    1. Initial program 34.7%

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

      \[\leadsto \color{blue}{\frac{1}{2} + \frac{-1}{24} \cdot {x}^{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

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

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

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{24}, \frac{1}{2}\right) \]
      5. lower-*.f6467.0

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, -0.041666666666666664, 0.5\right) \]
    5. Applied rewrites67.0%

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

    if 0.00559999999999999994 < x

    1. Initial program 99.3%

      \[\frac{1 - \cos x}{x \cdot x} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 5: 63.3% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x}{x \cdot x}\\ \mathbf{if}\;x \leq 290000000000:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(0.001388888888888889 \cdot x, x, -0.041666666666666664\right), 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(t\_0, t\_0, \frac{-1}{x \cdot x}\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (/ x (* x x))))
   (if (<= x 290000000000.0)
     (fma (* x x) (fma (* 0.001388888888888889 x) x -0.041666666666666664) 0.5)
     (fma t_0 t_0 (/ -1.0 (* x x))))))
double code(double x) {
	double t_0 = x / (x * x);
	double tmp;
	if (x <= 290000000000.0) {
		tmp = fma((x * x), fma((0.001388888888888889 * x), x, -0.041666666666666664), 0.5);
	} else {
		tmp = fma(t_0, t_0, (-1.0 / (x * x)));
	}
	return tmp;
}
function code(x)
	t_0 = Float64(x / Float64(x * x))
	tmp = 0.0
	if (x <= 290000000000.0)
		tmp = fma(Float64(x * x), fma(Float64(0.001388888888888889 * x), x, -0.041666666666666664), 0.5);
	else
		tmp = fma(t_0, t_0, Float64(-1.0 / Float64(x * x)));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[(x / N[(x * x), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 290000000000.0], N[(N[(x * x), $MachinePrecision] * N[(N[(0.001388888888888889 * x), $MachinePrecision] * x + -0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision], N[(t$95$0 * t$95$0 + N[(-1.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{x}{x \cdot x}\\
\mathbf{if}\;x \leq 290000000000:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(0.001388888888888889 \cdot x, x, -0.041666666666666664\right), 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(t\_0, t\_0, \frac{-1}{x \cdot x}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 2.9e11

    1. Initial program 35.4%

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

      \[\leadsto \color{blue}{\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{720} \cdot {x}^{2} - \frac{1}{24}\right)} \]
    4. Applied rewrites66.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(0.001388888888888889 \cdot x, x, -0.041666666666666664\right), 0.5\right)} \]

    if 2.9e11 < x

    1. Initial program 99.3%

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

        \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
      2. flip--N/A

        \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
      3. lower-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
      4. metadata-evalN/A

        \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
      5. lift-cos.f64N/A

        \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
      6. lift-cos.f64N/A

        \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
      7. 1-sub-cosN/A

        \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
      8. pow2N/A

        \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
      9. lower-pow.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
      10. lower-sin.f64N/A

        \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
      11. +-commutativeN/A

        \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
      12. lower-+.f6499.2

        \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
    4. Applied rewrites99.2%

      \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
    5. Step-by-step derivation
      1. lift-/.f64N/A

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

        \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
      3. associate-/l/N/A

        \[\leadsto \color{blue}{\frac{{\sin x}^{2}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)}} \]
      4. lift-pow.f64N/A

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

        \[\leadsto \frac{\color{blue}{\sin x \cdot \sin x}}{\left(\cos x + 1\right) \cdot \left(x \cdot x\right)} \]
      6. times-fracN/A

        \[\leadsto \color{blue}{\frac{\sin x}{\cos x + 1} \cdot \frac{\sin x}{x \cdot x}} \]
      7. lower-*.f64N/A

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

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

        \[\leadsto \frac{\sin x}{\color{blue}{\cos x + 1}} \cdot \frac{\sin x}{x \cdot x} \]
      10. +-commutativeN/A

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

        \[\leadsto \frac{\sin x}{1 + \color{blue}{\cos x}} \cdot \frac{\sin x}{x \cdot x} \]
      12. hang-0p-tanN/A

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

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

        \[\leadsto \tan \color{blue}{\left(\frac{x}{2}\right)} \cdot \frac{\sin x}{x \cdot x} \]
      15. lower-/.f6499.6

        \[\leadsto \tan \left(\frac{x}{2}\right) \cdot \color{blue}{\frac{\sin x}{x \cdot x}} \]
    6. Applied rewrites99.6%

      \[\leadsto \color{blue}{\tan \left(\frac{x}{2}\right) \cdot \frac{\sin x}{x \cdot x}} \]
    7. Applied rewrites98.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{x}{x \cdot x}, \frac{x}{x \cdot x}, \frac{x \cdot \frac{-\cos x}{x}}{x \cdot x}\right)} \]
    8. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(\frac{x}{x \cdot x}, \frac{x}{x \cdot x}, \frac{\color{blue}{-1}}{x \cdot x}\right) \]
    9. Step-by-step derivation
      1. Applied rewrites53.3%

        \[\leadsto \mathsf{fma}\left(\frac{x}{x \cdot x}, \frac{x}{x \cdot x}, \frac{\color{blue}{-1}}{x \cdot x}\right) \]
    10. Recombined 2 regimes into one program.
    11. Add Preprocessing

    Alternative 6: 63.3% accurate, 2.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 2.15 \cdot 10^{+80}:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{-1}{x \cdot x}\right)\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (<= x 2.15e+80) 0.5 (fma (/ -1.0 x) (/ -1.0 x) (/ -1.0 (* x x)))))
    double code(double x) {
    	double tmp;
    	if (x <= 2.15e+80) {
    		tmp = 0.5;
    	} else {
    		tmp = fma((-1.0 / x), (-1.0 / x), (-1.0 / (x * x)));
    	}
    	return tmp;
    }
    
    function code(x)
    	tmp = 0.0
    	if (x <= 2.15e+80)
    		tmp = 0.5;
    	else
    		tmp = fma(Float64(-1.0 / x), Float64(-1.0 / x), Float64(-1.0 / Float64(x * x)));
    	end
    	return tmp
    end
    
    code[x_] := If[LessEqual[x, 2.15e+80], 0.5, N[(N[(-1.0 / x), $MachinePrecision] * N[(-1.0 / x), $MachinePrecision] + N[(-1.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;x \leq 2.15 \cdot 10^{+80}:\\
    \;\;\;\;0.5\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{-1}{x \cdot x}\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 2.15000000000000002e80

      1. Initial program 40.2%

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

        \[\leadsto \color{blue}{\frac{1}{2}} \]
      4. Step-by-step derivation
        1. Applied rewrites62.5%

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

        if 2.15000000000000002e80 < x

        1. Initial program 99.7%

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

            \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
          2. flip--N/A

            \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
          3. lower-/.f64N/A

            \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
          4. metadata-evalN/A

            \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
          5. lift-cos.f64N/A

            \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
          6. lift-cos.f64N/A

            \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
          7. 1-sub-cosN/A

            \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
          8. pow2N/A

            \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
          9. lower-pow.f64N/A

            \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
          10. lower-sin.f64N/A

            \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
          11. +-commutativeN/A

            \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
          12. lower-+.f6499.5

            \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
        4. Applied rewrites99.5%

          \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
        5. Step-by-step derivation
          1. lift-/.f64N/A

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

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

            \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{\cos x + 1}}{x \cdot x} \]
          4. unpow2N/A

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

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

            \[\leadsto \frac{\frac{\sin x \cdot \color{blue}{\sin x}}{\cos x + 1}}{x \cdot x} \]
          7. 1-sub-cosN/A

            \[\leadsto \frac{\frac{\color{blue}{1 - \cos x \cdot \cos x}}{\cos x + 1}}{x \cdot x} \]
          8. metadata-evalN/A

            \[\leadsto \frac{\frac{\color{blue}{1 \cdot 1} - \cos x \cdot \cos x}{\cos x + 1}}{x \cdot x} \]
          9. lift-cos.f64N/A

            \[\leadsto \frac{\frac{1 \cdot 1 - \color{blue}{\cos x} \cdot \cos x}{\cos x + 1}}{x \cdot x} \]
          10. lift-cos.f64N/A

            \[\leadsto \frac{\frac{1 \cdot 1 - \cos x \cdot \color{blue}{\cos x}}{\cos x + 1}}{x \cdot x} \]
          11. lift-+.f64N/A

            \[\leadsto \frac{\frac{1 \cdot 1 - \cos x \cdot \cos x}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
          12. +-commutativeN/A

            \[\leadsto \frac{\frac{1 \cdot 1 - \cos x \cdot \cos x}{\color{blue}{1 + \cos x}}}{x \cdot x} \]
          13. flip--N/A

            \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
          14. *-rgt-identityN/A

            \[\leadsto \frac{1 - \color{blue}{\cos x \cdot 1}}{x \cdot x} \]
          15. fp-cancel-sub-sign-invN/A

            \[\leadsto \frac{\color{blue}{1 + \left(\mathsf{neg}\left(\cos x\right)\right) \cdot 1}}{x \cdot x} \]
          16. div-addN/A

            \[\leadsto \color{blue}{\frac{1}{x \cdot x} + \frac{\left(\mathsf{neg}\left(\cos x\right)\right) \cdot 1}{x \cdot x}} \]
        6. Applied rewrites99.4%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{\left(-\cos x\right) \cdot 1}{x \cdot x}\right)} \]
        7. Taylor expanded in x around 0

          \[\leadsto \mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{\color{blue}{-1} \cdot 1}{x \cdot x}\right) \]
        8. Step-by-step derivation
          1. Applied rewrites69.5%

            \[\leadsto \mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{\color{blue}{-1} \cdot 1}{x \cdot x}\right) \]
        9. Recombined 2 regimes into one program.
        10. Final simplification63.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 2.15 \cdot 10^{+80}:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{-1}{x}, \frac{-1}{x}, \frac{-1}{x \cdot x}\right)\\ \end{array} \]
        11. Add Preprocessing

        Alternative 7: 63.3% accurate, 17.1× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 7.6 \cdot 10^{+76}:\\ \;\;\;\;0.5\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
        (FPCore (x) :precision binary64 (if (<= x 7.6e+76) 0.5 0.0))
        double code(double x) {
        	double tmp;
        	if (x <= 7.6e+76) {
        		tmp = 0.5;
        	} else {
        		tmp = 0.0;
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= 7.6d+76) then
                tmp = 0.5d0
            else
                tmp = 0.0d0
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= 7.6e+76) {
        		tmp = 0.5;
        	} else {
        		tmp = 0.0;
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= 7.6e+76:
        		tmp = 0.5
        	else:
        		tmp = 0.0
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= 7.6e+76)
        		tmp = 0.5;
        	else
        		tmp = 0.0;
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= 7.6e+76)
        		tmp = 0.5;
        	else
        		tmp = 0.0;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, 7.6e+76], 0.5, 0.0]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 7.6 \cdot 10^{+76}:\\
        \;\;\;\;0.5\\
        
        \mathbf{else}:\\
        \;\;\;\;0\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 7.60000000000000049e76

          1. Initial program 39.6%

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

            \[\leadsto \color{blue}{\frac{1}{2}} \]
          4. Step-by-step derivation
            1. Applied rewrites63.1%

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

            if 7.60000000000000049e76 < x

            1. Initial program 99.7%

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

                \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
              2. flip--N/A

                \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
              3. lower-/.f64N/A

                \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
              4. metadata-evalN/A

                \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
              5. lift-cos.f64N/A

                \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
              6. lift-cos.f64N/A

                \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
              7. 1-sub-cosN/A

                \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
              8. pow2N/A

                \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
              9. lower-pow.f64N/A

                \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
              10. lower-sin.f64N/A

                \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
              11. +-commutativeN/A

                \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
              12. lower-+.f6499.5

                \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
            4. Applied rewrites99.5%

              \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
            5. Step-by-step derivation
              1. lift-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{{\sin x}^{2}}{\cos x + 1}}{x \cdot x}} \]
              2. frac-2negN/A

                \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\frac{{\sin x}^{2}}{\cos x + 1}\right)}{\mathsf{neg}\left(x \cdot x\right)}} \]
              3. lift-/.f64N/A

                \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}\right)}{\mathsf{neg}\left(x \cdot x\right)} \]
              4. distribute-neg-fracN/A

                \[\leadsto \frac{\color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\cos x + 1}}}{\mathsf{neg}\left(x \cdot x\right)} \]
              5. lift-pow.f64N/A

                \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{{\sin x}^{2}}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              6. unpow2N/A

                \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{\sin x \cdot \sin x}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              7. lift-sin.f64N/A

                \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{\sin x} \cdot \sin x\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              8. lift-sin.f64N/A

                \[\leadsto \frac{\frac{\mathsf{neg}\left(\sin x \cdot \color{blue}{\sin x}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              9. sub-1-cosN/A

                \[\leadsto \frac{\frac{\color{blue}{\cos x \cdot \cos x - 1}}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              10. lift-cos.f64N/A

                \[\leadsto \frac{\frac{\color{blue}{\cos x} \cdot \cos x - 1}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              11. lift-cos.f64N/A

                \[\leadsto \frac{\frac{\cos x \cdot \color{blue}{\cos x} - 1}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              12. metadata-evalN/A

                \[\leadsto \frac{\frac{\cos x \cdot \cos x - \color{blue}{1 \cdot 1}}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              13. lift-+.f64N/A

                \[\leadsto \frac{\frac{\cos x \cdot \cos x - 1 \cdot 1}{\color{blue}{\cos x + 1}}}{\mathsf{neg}\left(x \cdot x\right)} \]
              14. flip--N/A

                \[\leadsto \frac{\color{blue}{\cos x - 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
              15. mul-1-negN/A

                \[\leadsto \frac{\cos x - 1}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
              16. lift-*.f64N/A

                \[\leadsto \frac{\cos x - 1}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
              17. div-subN/A

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

                \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\color{blue}{\mathsf{neg}\left(-1\right)}}{-1 \cdot \left(x \cdot x\right)} \]
              19. lift-*.f64N/A

                \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\mathsf{neg}\left(-1\right)}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
              20. mul-1-negN/A

                \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\mathsf{neg}\left(-1\right)}{\color{blue}{\mathsf{neg}\left(x \cdot x\right)}} \]
            6. Applied rewrites99.6%

              \[\leadsto \color{blue}{\frac{-\cos x}{x \cdot x} - \frac{-1}{x \cdot x}} \]
            7. Step-by-step derivation
              1. lift-neg.f64N/A

                \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(\cos x\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
              2. lift-cos.f64N/A

                \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\cos x}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
              3. cos-neg-revN/A

                \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\cos \left(\mathsf{neg}\left(x\right)\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
              4. lift-neg.f64N/A

                \[\leadsto \frac{\mathsf{neg}\left(\cos \color{blue}{\left(-x\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
              5. cos-+PI-revN/A

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

                \[\leadsto \frac{\color{blue}{\cos \left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
              7. lower-+.f64N/A

                \[\leadsto \frac{\cos \color{blue}{\left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
              8. lower-PI.f6469.9

                \[\leadsto \frac{\cos \left(\left(-x\right) + \color{blue}{\mathsf{PI}\left(\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
            8. Applied rewrites69.9%

              \[\leadsto \frac{\color{blue}{\cos \left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
            9. Taylor expanded in x around 0

              \[\leadsto \color{blue}{\frac{1 + \cos \mathsf{PI}\left(\right)}{{x}^{2}}} \]
            10. Step-by-step derivation
              1. cos-PIN/A

                \[\leadsto \frac{1 + \color{blue}{-1}}{{x}^{2}} \]
              2. metadata-evalN/A

                \[\leadsto \frac{\color{blue}{0}}{{x}^{2}} \]
              3. div066.6

                \[\leadsto \color{blue}{0} \]
            11. Applied rewrites66.6%

              \[\leadsto \color{blue}{0} \]
          5. Recombined 2 regimes into one program.
          6. Add Preprocessing

          Alternative 8: 28.0% accurate, 120.0× speedup?

          \[\begin{array}{l} \\ 0 \end{array} \]
          (FPCore (x) :precision binary64 0.0)
          double code(double x) {
          	return 0.0;
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = 0.0d0
          end function
          
          public static double code(double x) {
          	return 0.0;
          }
          
          def code(x):
          	return 0.0
          
          function code(x)
          	return 0.0
          end
          
          function tmp = code(x)
          	tmp = 0.0;
          end
          
          code[x_] := 0.0
          
          \begin{array}{l}
          
          \\
          0
          \end{array}
          
          Derivation
          1. Initial program 51.1%

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

              \[\leadsto \frac{\color{blue}{1 - \cos x}}{x \cdot x} \]
            2. flip--N/A

              \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
            3. lower-/.f64N/A

              \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x} \]
            4. metadata-evalN/A

              \[\leadsto \frac{\frac{\color{blue}{1} - \cos x \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
            5. lift-cos.f64N/A

              \[\leadsto \frac{\frac{1 - \color{blue}{\cos x} \cdot \cos x}{1 + \cos x}}{x \cdot x} \]
            6. lift-cos.f64N/A

              \[\leadsto \frac{\frac{1 - \cos x \cdot \color{blue}{\cos x}}{1 + \cos x}}{x \cdot x} \]
            7. 1-sub-cosN/A

              \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x} \]
            8. pow2N/A

              \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
            9. lower-pow.f64N/A

              \[\leadsto \frac{\frac{\color{blue}{{\sin x}^{2}}}{1 + \cos x}}{x \cdot x} \]
            10. lower-sin.f64N/A

              \[\leadsto \frac{\frac{{\color{blue}{\sin x}}^{2}}{1 + \cos x}}{x \cdot x} \]
            11. +-commutativeN/A

              \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
            12. lower-+.f6475.8

              \[\leadsto \frac{\frac{{\sin x}^{2}}{\color{blue}{\cos x + 1}}}{x \cdot x} \]
          4. Applied rewrites75.8%

            \[\leadsto \frac{\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}}{x \cdot x} \]
          5. Step-by-step derivation
            1. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{\frac{{\sin x}^{2}}{\cos x + 1}}{x \cdot x}} \]
            2. frac-2negN/A

              \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\frac{{\sin x}^{2}}{\cos x + 1}\right)}{\mathsf{neg}\left(x \cdot x\right)}} \]
            3. lift-/.f64N/A

              \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\frac{{\sin x}^{2}}{\cos x + 1}}\right)}{\mathsf{neg}\left(x \cdot x\right)} \]
            4. distribute-neg-fracN/A

              \[\leadsto \frac{\color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\cos x + 1}}}{\mathsf{neg}\left(x \cdot x\right)} \]
            5. lift-pow.f64N/A

              \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{{\sin x}^{2}}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            6. unpow2N/A

              \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{\sin x \cdot \sin x}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            7. lift-sin.f64N/A

              \[\leadsto \frac{\frac{\mathsf{neg}\left(\color{blue}{\sin x} \cdot \sin x\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            8. lift-sin.f64N/A

              \[\leadsto \frac{\frac{\mathsf{neg}\left(\sin x \cdot \color{blue}{\sin x}\right)}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            9. sub-1-cosN/A

              \[\leadsto \frac{\frac{\color{blue}{\cos x \cdot \cos x - 1}}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            10. lift-cos.f64N/A

              \[\leadsto \frac{\frac{\color{blue}{\cos x} \cdot \cos x - 1}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            11. lift-cos.f64N/A

              \[\leadsto \frac{\frac{\cos x \cdot \color{blue}{\cos x} - 1}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            12. metadata-evalN/A

              \[\leadsto \frac{\frac{\cos x \cdot \cos x - \color{blue}{1 \cdot 1}}{\cos x + 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            13. lift-+.f64N/A

              \[\leadsto \frac{\frac{\cos x \cdot \cos x - 1 \cdot 1}{\color{blue}{\cos x + 1}}}{\mathsf{neg}\left(x \cdot x\right)} \]
            14. flip--N/A

              \[\leadsto \frac{\color{blue}{\cos x - 1}}{\mathsf{neg}\left(x \cdot x\right)} \]
            15. mul-1-negN/A

              \[\leadsto \frac{\cos x - 1}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
            16. lift-*.f64N/A

              \[\leadsto \frac{\cos x - 1}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
            17. div-subN/A

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

              \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\color{blue}{\mathsf{neg}\left(-1\right)}}{-1 \cdot \left(x \cdot x\right)} \]
            19. lift-*.f64N/A

              \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\mathsf{neg}\left(-1\right)}{\color{blue}{-1 \cdot \left(x \cdot x\right)}} \]
            20. mul-1-negN/A

              \[\leadsto \frac{\cos x}{-1 \cdot \left(x \cdot x\right)} - \frac{\mathsf{neg}\left(-1\right)}{\color{blue}{\mathsf{neg}\left(x \cdot x\right)}} \]
          6. Applied rewrites50.9%

            \[\leadsto \color{blue}{\frac{-\cos x}{x \cdot x} - \frac{-1}{x \cdot x}} \]
          7. Step-by-step derivation
            1. lift-neg.f64N/A

              \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(\cos x\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
            2. lift-cos.f64N/A

              \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\cos x}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
            3. cos-neg-revN/A

              \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\cos \left(\mathsf{neg}\left(x\right)\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
            4. lift-neg.f64N/A

              \[\leadsto \frac{\mathsf{neg}\left(\cos \color{blue}{\left(-x\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
            5. cos-+PI-revN/A

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

              \[\leadsto \frac{\color{blue}{\cos \left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
            7. lower-+.f64N/A

              \[\leadsto \frac{\cos \color{blue}{\left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
            8. lower-PI.f6431.0

              \[\leadsto \frac{\cos \left(\left(-x\right) + \color{blue}{\mathsf{PI}\left(\right)}\right)}{x \cdot x} - \frac{-1}{x \cdot x} \]
          8. Applied rewrites31.0%

            \[\leadsto \frac{\color{blue}{\cos \left(\left(-x\right) + \mathsf{PI}\left(\right)\right)}}{x \cdot x} - \frac{-1}{x \cdot x} \]
          9. Taylor expanded in x around 0

            \[\leadsto \color{blue}{\frac{1 + \cos \mathsf{PI}\left(\right)}{{x}^{2}}} \]
          10. Step-by-step derivation
            1. cos-PIN/A

              \[\leadsto \frac{1 + \color{blue}{-1}}{{x}^{2}} \]
            2. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{0}}{{x}^{2}} \]
            3. div027.6

              \[\leadsto \color{blue}{0} \]
          11. Applied rewrites27.6%

            \[\leadsto \color{blue}{0} \]
          12. Add Preprocessing

          Reproduce

          ?
          herbie shell --seed 2024340 
          (FPCore (x)
            :name "cos2 (problem 3.4.1)"
            :precision binary64
            (/ (- 1.0 (cos x)) (* x x)))