Graphics.Rasterific.Svg.PathConverter:segmentToBezier from rasterific-svg-0.2.3.1, A

Percentage Accurate: 76.6% → 99.5%
Time: 18.5s
Alternatives: 15
Speedup: 1.5×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(x \cdot 0.5\right)\\ \frac{\left(\frac{8}{3} \cdot t_0\right) \cdot t_0}{\sin x} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (sin (* x 0.5)))) (/ (* (* (/ 8.0 3.0) t_0) t_0) (sin x))))
double code(double x) {
	double t_0 = sin((x * 0.5));
	return (((8.0 / 3.0) * t_0) * t_0) / sin(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = sin((x * 0.5d0))
    code = (((8.0d0 / 3.0d0) * t_0) * t_0) / sin(x)
end function
public static double code(double x) {
	double t_0 = Math.sin((x * 0.5));
	return (((8.0 / 3.0) * t_0) * t_0) / Math.sin(x);
}
def code(x):
	t_0 = math.sin((x * 0.5))
	return (((8.0 / 3.0) * t_0) * t_0) / math.sin(x)
function code(x)
	t_0 = sin(Float64(x * 0.5))
	return Float64(Float64(Float64(Float64(8.0 / 3.0) * t_0) * t_0) / sin(x))
end
function tmp = code(x)
	t_0 = sin((x * 0.5));
	tmp = (((8.0 / 3.0) * t_0) * t_0) / sin(x);
end
code[x_] := Block[{t$95$0 = N[Sin[N[(x * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(N[(8.0 / 3.0), $MachinePrecision] * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision] / N[Sin[x], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(x \cdot 0.5\right)\\
\frac{\left(\frac{8}{3} \cdot t_0\right) \cdot t_0}{\sin x}
\end{array}
\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 15 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: 76.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(x \cdot 0.5\right)\\ \frac{\left(\frac{8}{3} \cdot t_0\right) \cdot t_0}{\sin x} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (sin (* x 0.5)))) (/ (* (* (/ 8.0 3.0) t_0) t_0) (sin x))))
double code(double x) {
	double t_0 = sin((x * 0.5));
	return (((8.0 / 3.0) * t_0) * t_0) / sin(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = sin((x * 0.5d0))
    code = (((8.0d0 / 3.0d0) * t_0) * t_0) / sin(x)
end function
public static double code(double x) {
	double t_0 = Math.sin((x * 0.5));
	return (((8.0 / 3.0) * t_0) * t_0) / Math.sin(x);
}
def code(x):
	t_0 = math.sin((x * 0.5))
	return (((8.0 / 3.0) * t_0) * t_0) / math.sin(x)
function code(x)
	t_0 = sin(Float64(x * 0.5))
	return Float64(Float64(Float64(Float64(8.0 / 3.0) * t_0) * t_0) / sin(x))
end
function tmp = code(x)
	t_0 = sin((x * 0.5));
	tmp = (((8.0 / 3.0) * t_0) * t_0) / sin(x);
end
code[x_] := Block[{t$95$0 = N[Sin[N[(x * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(N[(8.0 / 3.0), $MachinePrecision] * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision] / N[Sin[x], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(x \cdot 0.5\right)\\
\frac{\left(\frac{8}{3} \cdot t_0\right) \cdot t_0}{\sin x}
\end{array}
\end{array}

Alternative 1: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 0.0002:\\ \;\;\;\;\frac{t_0}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{{t_0}^{2}}{\sin x_m \cdot 0.375}\\ \end{array} \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (*
    x_s
    (if (<= x_m 0.0002)
      (* (/ t_0 0.375) (+ 0.5 (* (pow x_m 2.0) 0.0625)))
      (/ (pow t_0 2.0) (* (sin x_m) 0.375))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	double tmp;
	if (x_m <= 0.0002) {
		tmp = (t_0 / 0.375) * (0.5 + (pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = pow(t_0, 2.0) / (sin(x_m) * 0.375);
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin((x_m * 0.5d0))
    if (x_m <= 0.0002d0) then
        tmp = (t_0 / 0.375d0) * (0.5d0 + ((x_m ** 2.0d0) * 0.0625d0))
    else
        tmp = (t_0 ** 2.0d0) / (sin(x_m) * 0.375d0)
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	double tmp;
	if (x_m <= 0.0002) {
		tmp = (t_0 / 0.375) * (0.5 + (Math.pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = Math.pow(t_0, 2.0) / (Math.sin(x_m) * 0.375);
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	tmp = 0
	if x_m <= 0.0002:
		tmp = (t_0 / 0.375) * (0.5 + (math.pow(x_m, 2.0) * 0.0625))
	else:
		tmp = math.pow(t_0, 2.0) / (math.sin(x_m) * 0.375)
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	tmp = 0.0
	if (x_m <= 0.0002)
		tmp = Float64(Float64(t_0 / 0.375) * Float64(0.5 + Float64((x_m ^ 2.0) * 0.0625)));
	else
		tmp = Float64((t_0 ^ 2.0) / Float64(sin(x_m) * 0.375));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = 0.0;
	if (x_m <= 0.0002)
		tmp = (t_0 / 0.375) * (0.5 + ((x_m ^ 2.0) * 0.0625));
	else
		tmp = (t_0 ^ 2.0) / (sin(x_m) * 0.375);
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * If[LessEqual[x$95$m, 0.0002], N[(N[(t$95$0 / 0.375), $MachinePrecision] * N[(0.5 + N[(N[Power[x$95$m, 2.0], $MachinePrecision] * 0.0625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Power[t$95$0, 2.0], $MachinePrecision] / N[(N[Sin[x$95$m], $MachinePrecision] * 0.375), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 0.0002:\\
\;\;\;\;\frac{t_0}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{{t_0}^{2}}{\sin x_m \cdot 0.375}\\


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

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 62.5%

      \[\leadsto \color{blue}{\left(0.5 + 0.0625 \cdot {x}^{2}\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    7. Step-by-step derivation
      1. *-commutative62.5%

        \[\leadsto \left(0.5 + \color{blue}{{x}^{2} \cdot 0.0625}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    8. Simplified62.5%

      \[\leadsto \color{blue}{\left(0.5 + {x}^{2} \cdot 0.0625\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 2.0000000000000001e-4 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right)}}{\sin x} \]
      2. remove-double-neg98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \color{blue}{\left(-\left(-\sin \left(x \cdot 0.5\right)\right)\right)}\right)}{\sin x} \]
      3. sin-neg98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\color{blue}{\sin \left(-x \cdot 0.5\right)}\right)\right)}{\sin x} \]
      4. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}\right)\right)}{\sin x} \]
      5. distribute-rgt-neg-in98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)}}{\sin x} \]
      6. associate-*l/98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)} \]
      7. *-commutative98.9%

        \[\leadsto \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}} \]
      8. distribute-rgt-neg-in98.9%

        \[\leadsto \color{blue}{\left(\frac{8}{3} \cdot \left(-\sin \left(\left(-x\right) \cdot 0.5\right)\right)\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      9. distribute-lft-neg-out98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(-x \cdot 0.5\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      10. sin-neg98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \left(-\color{blue}{\left(-\sin \left(x \cdot 0.5\right)\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      11. remove-double-neg98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \color{blue}{\sin \left(x \cdot 0.5\right)}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      12. associate-*l*98.9%

        \[\leadsto \color{blue}{\frac{8}{3} \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
    3. Simplified98.9%

      \[\leadsto \color{blue}{2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
    4. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right) \cdot 2.6666666666666665} \]
      2. associate-*r/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \cdot 2.6666666666666665 \]
      3. associate-/r/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      4. pow299.1%

        \[\leadsto \frac{\color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}}{\frac{\sin x}{2.6666666666666665}} \]
      5. div-inv99.2%

        \[\leadsto \frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      6. metadata-eval99.2%

        \[\leadsto \frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x \cdot \color{blue}{0.375}} \]
    5. Applied egg-rr99.2%

      \[\leadsto \color{blue}{\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x \cdot 0.375}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.0002:\\ \;\;\;\;\frac{\sin \left(x \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x \cdot 0.375}\\ \end{array} \]

Alternative 2: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \left(\frac{1}{\frac{\sin x_m}{t_0}} \cdot \frac{t_0}{0.375}\right) \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (* x_s (* (/ 1.0 (/ (sin x_m) t_0)) (/ t_0 0.375)))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	return x_s * ((1.0 / (sin(x_m) / t_0)) * (t_0 / 0.375));
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    t_0 = sin((x_m * 0.5d0))
    code = x_s * ((1.0d0 / (sin(x_m) / t_0)) * (t_0 / 0.375d0))
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	return x_s * ((1.0 / (Math.sin(x_m) / t_0)) * (t_0 / 0.375));
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	return x_s * ((1.0 / (math.sin(x_m) / t_0)) * (t_0 / 0.375))
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	return Float64(x_s * Float64(Float64(1.0 / Float64(sin(x_m) / t_0)) * Float64(t_0 / 0.375)))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = x_s * ((1.0 / (sin(x_m) / t_0)) * (t_0 / 0.375));
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * N[(N[(1.0 / N[(N[Sin[x$95$m], $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision] * N[(t$95$0 / 0.375), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \left(\frac{1}{\frac{\sin x_m}{t_0}} \cdot \frac{t_0}{0.375}\right)
\end{array}
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    3. *-lft-identity99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. metadata-eval99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    5. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    6. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    7. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    8. neg-mul-199.2%

      \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    9. sin-neg99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    10. distribute-lft-neg-out99.2%

      \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    11. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    12. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    13. associate-/l/99.2%

      \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
    14. associate-/r*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
  4. Step-by-step derivation
    1. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
    3. associate-*l/99.1%

      \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
    4. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
    5. associate-*l/75.3%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
    6. div-inv75.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
    7. times-frac99.4%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
    8. metadata-eval99.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
  5. Applied egg-rr99.4%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
  6. Step-by-step derivation
    1. clear-num99.4%

      \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    2. inv-pow99.4%

      \[\leadsto \color{blue}{{\left(\frac{\sin x}{\sin \left(x \cdot 0.5\right)}\right)}^{-1}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
  7. Applied egg-rr99.4%

    \[\leadsto \color{blue}{{\left(\frac{\sin x}{\sin \left(x \cdot 0.5\right)}\right)}^{-1}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
  8. Step-by-step derivation
    1. unpow-199.4%

      \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
  9. Applied egg-rr99.4%

    \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
  10. Final simplification99.4%

    \[\leadsto \frac{1}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

Alternative 3: 99.2% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \left(2.6666666666666665 \cdot \left(t_0 \cdot \frac{t_0}{\sin x_m}\right)\right) \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (* x_s (* 2.6666666666666665 (* t_0 (/ t_0 (sin x_m)))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	return x_s * (2.6666666666666665 * (t_0 * (t_0 / sin(x_m))));
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    t_0 = sin((x_m * 0.5d0))
    code = x_s * (2.6666666666666665d0 * (t_0 * (t_0 / sin(x_m))))
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	return x_s * (2.6666666666666665 * (t_0 * (t_0 / Math.sin(x_m))));
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	return x_s * (2.6666666666666665 * (t_0 * (t_0 / math.sin(x_m))))
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	return Float64(x_s * Float64(2.6666666666666665 * Float64(t_0 * Float64(t_0 / sin(x_m)))))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = x_s * (2.6666666666666665 * (t_0 * (t_0 / sin(x_m))));
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * N[(2.6666666666666665 * N[(t$95$0 * N[(t$95$0 / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \left(2.6666666666666665 \cdot \left(t_0 \cdot \frac{t_0}{\sin x_m}\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. *-commutative75.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right)}}{\sin x} \]
    2. remove-double-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \color{blue}{\left(-\left(-\sin \left(x \cdot 0.5\right)\right)\right)}\right)}{\sin x} \]
    3. sin-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\color{blue}{\sin \left(-x \cdot 0.5\right)}\right)\right)}{\sin x} \]
    4. distribute-lft-neg-out75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}\right)\right)}{\sin x} \]
    5. distribute-rgt-neg-in75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)}}{\sin x} \]
    6. associate-*l/99.1%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)} \]
    7. *-commutative99.1%

      \[\leadsto \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}} \]
    8. distribute-rgt-neg-in99.1%

      \[\leadsto \color{blue}{\left(\frac{8}{3} \cdot \left(-\sin \left(\left(-x\right) \cdot 0.5\right)\right)\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
    9. distribute-lft-neg-out99.1%

      \[\leadsto \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(-x \cdot 0.5\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
    10. sin-neg99.1%

      \[\leadsto \left(\frac{8}{3} \cdot \left(-\color{blue}{\left(-\sin \left(x \cdot 0.5\right)\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
    11. remove-double-neg99.1%

      \[\leadsto \left(\frac{8}{3} \cdot \color{blue}{\sin \left(x \cdot 0.5\right)}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
    12. associate-*l*99.1%

      \[\leadsto \color{blue}{\frac{8}{3} \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
  3. Simplified99.1%

    \[\leadsto \color{blue}{2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
  4. Final simplification99.1%

    \[\leadsto 2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right) \]

Alternative 4: 99.2% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \left(t_0 \cdot \frac{t_0}{\frac{\sin x_m}{2.6666666666666665}}\right) \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (* x_s (* t_0 (/ t_0 (/ (sin x_m) 2.6666666666666665))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	return x_s * (t_0 * (t_0 / (sin(x_m) / 2.6666666666666665)));
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    t_0 = sin((x_m * 0.5d0))
    code = x_s * (t_0 * (t_0 / (sin(x_m) / 2.6666666666666665d0)))
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	return x_s * (t_0 * (t_0 / (Math.sin(x_m) / 2.6666666666666665)));
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	return x_s * (t_0 * (t_0 / (math.sin(x_m) / 2.6666666666666665)))
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	return Float64(x_s * Float64(t_0 * Float64(t_0 / Float64(sin(x_m) / 2.6666666666666665))))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = x_s * (t_0 * (t_0 / (sin(x_m) / 2.6666666666666665)));
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * N[(t$95$0 * N[(t$95$0 / N[(N[Sin[x$95$m], $MachinePrecision] / 2.6666666666666665), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \left(t_0 \cdot \frac{t_0}{\frac{\sin x_m}{2.6666666666666665}}\right)
\end{array}
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. *-commutative75.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right)}}{\sin x} \]
    2. remove-double-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \color{blue}{\left(-\left(-\sin \left(x \cdot 0.5\right)\right)\right)}\right)}{\sin x} \]
    3. sin-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\color{blue}{\sin \left(-x \cdot 0.5\right)}\right)\right)}{\sin x} \]
    4. distribute-lft-neg-out75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}\right)\right)}{\sin x} \]
    5. distribute-rgt-neg-in75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)}}{\sin x} \]
    6. associate-*r/99.2%

      \[\leadsto \color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\sin x}} \]
    7. *-commutative99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{-\color{blue}{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}}{\sin x} \]
    8. distribute-lft-neg-in99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\color{blue}{\left(-\sin \left(\left(-x\right) \cdot 0.5\right)\right) \cdot \frac{8}{3}}}{\sin x} \]
    9. distribute-lft-neg-out99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\left(-\sin \color{blue}{\left(-x \cdot 0.5\right)}\right) \cdot \frac{8}{3}}{\sin x} \]
    10. sin-neg99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\left(-\color{blue}{\left(-\sin \left(x \cdot 0.5\right)\right)}\right) \cdot \frac{8}{3}}{\sin x} \]
    11. remove-double-neg99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\color{blue}{\sin \left(x \cdot 0.5\right)} \cdot \frac{8}{3}}{\sin x} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
  4. Final simplification99.2%

    \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}} \]

Alternative 5: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \left(\frac{t_0}{0.375} \cdot \frac{t_0}{\sin x_m}\right) \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5)))) (* x_s (* (/ t_0 0.375) (/ t_0 (sin x_m))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	return x_s * ((t_0 / 0.375) * (t_0 / sin(x_m)));
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    t_0 = sin((x_m * 0.5d0))
    code = x_s * ((t_0 / 0.375d0) * (t_0 / sin(x_m)))
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	return x_s * ((t_0 / 0.375) * (t_0 / Math.sin(x_m)));
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	return x_s * ((t_0 / 0.375) * (t_0 / math.sin(x_m)))
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	return Float64(x_s * Float64(Float64(t_0 / 0.375) * Float64(t_0 / sin(x_m))))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = x_s * ((t_0 / 0.375) * (t_0 / sin(x_m)));
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * N[(N[(t$95$0 / 0.375), $MachinePrecision] * N[(t$95$0 / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \left(\frac{t_0}{0.375} \cdot \frac{t_0}{\sin x_m}\right)
\end{array}
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    3. *-lft-identity99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. metadata-eval99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    5. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    6. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    7. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    8. neg-mul-199.2%

      \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    9. sin-neg99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    10. distribute-lft-neg-out99.2%

      \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    11. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    12. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    13. associate-/l/99.2%

      \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
    14. associate-/r*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
  4. Step-by-step derivation
    1. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
    3. associate-*l/99.1%

      \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
    4. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
    5. associate-*l/75.3%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
    6. div-inv75.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
    7. times-frac99.4%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
    8. metadata-eval99.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
  5. Applied egg-rr99.4%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
  6. Final simplification99.4%

    \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{0.375} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]

Alternative 6: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 5 \cdot 10^{-7}:\\ \;\;\;\;\frac{t_0}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;2.6666666666666665 \cdot \frac{{t_0}^{2}}{\sin x_m}\\ \end{array} \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (*
    x_s
    (if (<= x_m 5e-7)
      (* (/ t_0 0.375) (+ 0.5 (* (pow x_m 2.0) 0.0625)))
      (* 2.6666666666666665 (/ (pow t_0 2.0) (sin x_m)))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-7) {
		tmp = (t_0 / 0.375) * (0.5 + (pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = 2.6666666666666665 * (pow(t_0, 2.0) / sin(x_m));
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin((x_m * 0.5d0))
    if (x_m <= 5d-7) then
        tmp = (t_0 / 0.375d0) * (0.5d0 + ((x_m ** 2.0d0) * 0.0625d0))
    else
        tmp = 2.6666666666666665d0 * ((t_0 ** 2.0d0) / sin(x_m))
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-7) {
		tmp = (t_0 / 0.375) * (0.5 + (Math.pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = 2.6666666666666665 * (Math.pow(t_0, 2.0) / Math.sin(x_m));
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	tmp = 0
	if x_m <= 5e-7:
		tmp = (t_0 / 0.375) * (0.5 + (math.pow(x_m, 2.0) * 0.0625))
	else:
		tmp = 2.6666666666666665 * (math.pow(t_0, 2.0) / math.sin(x_m))
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	tmp = 0.0
	if (x_m <= 5e-7)
		tmp = Float64(Float64(t_0 / 0.375) * Float64(0.5 + Float64((x_m ^ 2.0) * 0.0625)));
	else
		tmp = Float64(2.6666666666666665 * Float64((t_0 ^ 2.0) / sin(x_m)));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = 0.0;
	if (x_m <= 5e-7)
		tmp = (t_0 / 0.375) * (0.5 + ((x_m ^ 2.0) * 0.0625));
	else
		tmp = 2.6666666666666665 * ((t_0 ^ 2.0) / sin(x_m));
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * If[LessEqual[x$95$m, 5e-7], N[(N[(t$95$0 / 0.375), $MachinePrecision] * N[(0.5 + N[(N[Power[x$95$m, 2.0], $MachinePrecision] * 0.0625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(2.6666666666666665 * N[(N[Power[t$95$0, 2.0], $MachinePrecision] / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 5 \cdot 10^{-7}:\\
\;\;\;\;\frac{t_0}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\

\mathbf{else}:\\
\;\;\;\;2.6666666666666665 \cdot \frac{{t_0}^{2}}{\sin x_m}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 4.99999999999999977e-7

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 62.5%

      \[\leadsto \color{blue}{\left(0.5 + 0.0625 \cdot {x}^{2}\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    7. Step-by-step derivation
      1. *-commutative62.5%

        \[\leadsto \left(0.5 + \color{blue}{{x}^{2} \cdot 0.0625}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    8. Simplified62.5%

      \[\leadsto \color{blue}{\left(0.5 + {x}^{2} \cdot 0.0625\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 4.99999999999999977e-7 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. div-inv98.9%

        \[\leadsto \color{blue}{\left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \frac{1}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. clear-num98.9%

        \[\leadsto \left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x}} \]
      3. associate-*r*98.9%

        \[\leadsto \color{blue}{2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
      4. *-commutative98.9%

        \[\leadsto \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right) \cdot 2.6666666666666665} \]
      5. associate-*r/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \cdot 2.6666666666666665 \]
      6. pow299.1%

        \[\leadsto \frac{\color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}}{\sin x} \cdot 2.6666666666666665 \]
    5. Applied egg-rr99.1%

      \[\leadsto \color{blue}{\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x} \cdot 2.6666666666666665} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 5 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sin \left(x \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;2.6666666666666665 \cdot \frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x}\\ \end{array} \]

Alternative 7: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 5 \cdot 10^{-9}:\\ \;\;\;\;0.5 \cdot \frac{t_0}{0.375}\\ \mathbf{else}:\\ \;\;\;\;{t_0}^{2} \cdot \frac{2.6666666666666665}{\sin x_m}\\ \end{array} \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (*
    x_s
    (if (<= x_m 5e-9)
      (* 0.5 (/ t_0 0.375))
      (* (pow t_0 2.0) (/ 2.6666666666666665 (sin x_m)))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-9) {
		tmp = 0.5 * (t_0 / 0.375);
	} else {
		tmp = pow(t_0, 2.0) * (2.6666666666666665 / sin(x_m));
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin((x_m * 0.5d0))
    if (x_m <= 5d-9) then
        tmp = 0.5d0 * (t_0 / 0.375d0)
    else
        tmp = (t_0 ** 2.0d0) * (2.6666666666666665d0 / sin(x_m))
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-9) {
		tmp = 0.5 * (t_0 / 0.375);
	} else {
		tmp = Math.pow(t_0, 2.0) * (2.6666666666666665 / Math.sin(x_m));
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	tmp = 0
	if x_m <= 5e-9:
		tmp = 0.5 * (t_0 / 0.375)
	else:
		tmp = math.pow(t_0, 2.0) * (2.6666666666666665 / math.sin(x_m))
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	tmp = 0.0
	if (x_m <= 5e-9)
		tmp = Float64(0.5 * Float64(t_0 / 0.375));
	else
		tmp = Float64((t_0 ^ 2.0) * Float64(2.6666666666666665 / sin(x_m)));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = 0.0;
	if (x_m <= 5e-9)
		tmp = 0.5 * (t_0 / 0.375);
	else
		tmp = (t_0 ^ 2.0) * (2.6666666666666665 / sin(x_m));
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * If[LessEqual[x$95$m, 5e-9], N[(0.5 * N[(t$95$0 / 0.375), $MachinePrecision]), $MachinePrecision], N[(N[Power[t$95$0, 2.0], $MachinePrecision] * N[(2.6666666666666665 / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 5 \cdot 10^{-9}:\\
\;\;\;\;0.5 \cdot \frac{t_0}{0.375}\\

\mathbf{else}:\\
\;\;\;\;{t_0}^{2} \cdot \frac{2.6666666666666665}{\sin x_m}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 5.0000000000000001e-9

    1. Initial program 68.2%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 65.3%

      \[\leadsto \color{blue}{0.5} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 5.0000000000000001e-9 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.0%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/98.8%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv99.0%

        \[\leadsto \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \frac{1}{\frac{\sin x}{2.6666666666666665}}} \]
      7. pow299.0%

        \[\leadsto \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}} \cdot \frac{1}{\frac{\sin x}{2.6666666666666665}} \]
      8. clear-num99.1%

        \[\leadsto {\sin \left(x \cdot 0.5\right)}^{2} \cdot \color{blue}{\frac{2.6666666666666665}{\sin x}} \]
    5. Applied egg-rr99.1%

      \[\leadsto \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2} \cdot \frac{2.6666666666666665}{\sin x}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 5 \cdot 10^{-9}:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;{\sin \left(x \cdot 0.5\right)}^{2} \cdot \frac{2.6666666666666665}{\sin x}\\ \end{array} \]

Alternative 8: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ \begin{array}{l} t_0 := \sin \left(x_m \cdot 0.5\right)\\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 5 \cdot 10^{-9}:\\ \;\;\;\;0.5 \cdot \frac{t_0}{0.375}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{{t_0}^{2}}{\sin x_m}}{0.375}\\ \end{array} \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (let* ((t_0 (sin (* x_m 0.5))))
   (*
    x_s
    (if (<= x_m 5e-9)
      (* 0.5 (/ t_0 0.375))
      (/ (/ (pow t_0 2.0) (sin x_m)) 0.375)))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double t_0 = sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-9) {
		tmp = 0.5 * (t_0 / 0.375);
	} else {
		tmp = (pow(t_0, 2.0) / sin(x_m)) / 0.375;
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin((x_m * 0.5d0))
    if (x_m <= 5d-9) then
        tmp = 0.5d0 * (t_0 / 0.375d0)
    else
        tmp = ((t_0 ** 2.0d0) / sin(x_m)) / 0.375d0
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double t_0 = Math.sin((x_m * 0.5));
	double tmp;
	if (x_m <= 5e-9) {
		tmp = 0.5 * (t_0 / 0.375);
	} else {
		tmp = (Math.pow(t_0, 2.0) / Math.sin(x_m)) / 0.375;
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	t_0 = math.sin((x_m * 0.5))
	tmp = 0
	if x_m <= 5e-9:
		tmp = 0.5 * (t_0 / 0.375)
	else:
		tmp = (math.pow(t_0, 2.0) / math.sin(x_m)) / 0.375
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	t_0 = sin(Float64(x_m * 0.5))
	tmp = 0.0
	if (x_m <= 5e-9)
		tmp = Float64(0.5 * Float64(t_0 / 0.375));
	else
		tmp = Float64(Float64((t_0 ^ 2.0) / sin(x_m)) / 0.375);
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	t_0 = sin((x_m * 0.5));
	tmp = 0.0;
	if (x_m <= 5e-9)
		tmp = 0.5 * (t_0 / 0.375);
	else
		tmp = ((t_0 ^ 2.0) / sin(x_m)) / 0.375;
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := Block[{t$95$0 = N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(x$95$s * If[LessEqual[x$95$m, 5e-9], N[(0.5 * N[(t$95$0 / 0.375), $MachinePrecision]), $MachinePrecision], N[(N[(N[Power[t$95$0, 2.0], $MachinePrecision] / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision] / 0.375), $MachinePrecision]]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
\begin{array}{l}
t_0 := \sin \left(x_m \cdot 0.5\right)\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 5 \cdot 10^{-9}:\\
\;\;\;\;0.5 \cdot \frac{t_0}{0.375}\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{{t_0}^{2}}{\sin x_m}}{0.375}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 5.0000000000000001e-9

    1. Initial program 68.2%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 65.3%

      \[\leadsto \color{blue}{0.5} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 5.0000000000000001e-9 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right)}}{\sin x} \]
      2. remove-double-neg98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \color{blue}{\left(-\left(-\sin \left(x \cdot 0.5\right)\right)\right)}\right)}{\sin x} \]
      3. sin-neg98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\color{blue}{\sin \left(-x \cdot 0.5\right)}\right)\right)}{\sin x} \]
      4. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}\right)\right)}{\sin x} \]
      5. distribute-rgt-neg-in98.9%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)}}{\sin x} \]
      6. associate-*l/98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)} \]
      7. *-commutative98.9%

        \[\leadsto \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}} \]
      8. distribute-rgt-neg-in98.9%

        \[\leadsto \color{blue}{\left(\frac{8}{3} \cdot \left(-\sin \left(\left(-x\right) \cdot 0.5\right)\right)\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      9. distribute-lft-neg-out98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(-x \cdot 0.5\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      10. sin-neg98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \left(-\color{blue}{\left(-\sin \left(x \cdot 0.5\right)\right)}\right)\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      11. remove-double-neg98.9%

        \[\leadsto \left(\frac{8}{3} \cdot \color{blue}{\sin \left(x \cdot 0.5\right)}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \]
      12. associate-*l*98.9%

        \[\leadsto \color{blue}{\frac{8}{3} \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
    3. Simplified98.9%

      \[\leadsto \color{blue}{2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right)} \]
    4. Step-by-step derivation
      1. *-commutative98.9%

        \[\leadsto \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\sin x}\right) \cdot 2.6666666666666665} \]
      2. associate-*r/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \cdot 2.6666666666666665 \]
      3. associate-/r/99.1%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      4. div-inv99.2%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      5. associate-/r*99.2%

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}}{\frac{1}{2.6666666666666665}}} \]
      6. pow299.2%

        \[\leadsto \frac{\frac{\color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}}{\sin x}}{\frac{1}{2.6666666666666665}} \]
      7. metadata-eval99.2%

        \[\leadsto \frac{\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x}}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.2%

      \[\leadsto \color{blue}{\frac{\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x}}{0.375}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 5 \cdot 10^{-9}:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{{\sin \left(x \cdot 0.5\right)}^{2}}{\sin x}}{0.375}\\ \end{array} \]

Alternative 9: 99.2% accurate, 1.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 0.0036:\\ \;\;\;\;\frac{\sin \left(x_m \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\cos x_m, -1.3333333333333333, 1.3333333333333333\right)}{\sin x_m}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (if (<= x_m 0.0036)
    (* (/ (sin (* x_m 0.5)) 0.375) (+ 0.5 (* (pow x_m 2.0) 0.0625)))
    (/ (fma (cos x_m) -1.3333333333333333 1.3333333333333333) (sin x_m)))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.0036) {
		tmp = (sin((x_m * 0.5)) / 0.375) * (0.5 + (pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = fma(cos(x_m), -1.3333333333333333, 1.3333333333333333) / sin(x_m);
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	tmp = 0.0
	if (x_m <= 0.0036)
		tmp = Float64(Float64(sin(Float64(x_m * 0.5)) / 0.375) * Float64(0.5 + Float64((x_m ^ 2.0) * 0.0625)));
	else
		tmp = Float64(fma(cos(x_m), -1.3333333333333333, 1.3333333333333333) / sin(x_m));
	end
	return Float64(x_s * tmp)
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[x$95$m, 0.0036], N[(N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] / 0.375), $MachinePrecision] * N[(0.5 + N[(N[Power[x$95$m, 2.0], $MachinePrecision] * 0.0625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Cos[x$95$m], $MachinePrecision] * -1.3333333333333333 + 1.3333333333333333), $MachinePrecision] / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 0.0036:\\
\;\;\;\;\frac{\sin \left(x_m \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\cos x_m, -1.3333333333333333, 1.3333333333333333\right)}{\sin x_m}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.0035999999999999999

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 62.5%

      \[\leadsto \color{blue}{\left(0.5 + 0.0625 \cdot {x}^{2}\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    7. Step-by-step derivation
      1. *-commutative62.5%

        \[\leadsto \left(0.5 + \color{blue}{{x}^{2} \cdot 0.0625}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    8. Simplified62.5%

      \[\leadsto \color{blue}{\left(0.5 + {x}^{2} \cdot 0.0625\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 0.0035999999999999999 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \]
      2. metadata-eval98.9%

        \[\leadsto \frac{\left(\color{blue}{\frac{8}{3}} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
      3. clear-num98.9%

        \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}}} \]
      4. associate-/r/98.9%

        \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right)} \]
      5. metadata-eval98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(\left(\color{blue}{2.6666666666666665} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right) \]
      6. associate-*l*98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \color{blue}{\left(2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)\right)} \]
      7. pow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}\right) \]
    5. Applied egg-rr98.9%

      \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot {\sin \left(x \cdot 0.5\right)}^{2}\right)} \]
    6. Step-by-step derivation
      1. unpow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)}\right) \]
      2. sin-mult98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    7. Applied egg-rr98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    8. Step-by-step derivation
      1. div-sub98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right)}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)}\right) \]
      2. +-inverses98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\cos \color{blue}{0}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      3. cos-098.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\color{blue}{1}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      4. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\color{blue}{0.5} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      5. distribute-lft-out98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{\left(x \cdot \left(0.5 + 0.5\right)\right)}}{2}\right)\right) \]
      6. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \left(x \cdot \color{blue}{1}\right)}{2}\right)\right) \]
      7. *-rgt-identity98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{x}}{2}\right)\right) \]
    9. Simplified98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(0.5 - \frac{\cos x}{2}\right)}\right) \]
    10. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{2.6666666666666665 \cdot \frac{0.5 - 0.5 \cdot \cos x}{\sin x}} \]
    11. Step-by-step derivation
      1. associate-*r/98.6%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \left(0.5 - 0.5 \cdot \cos x\right)}{\sin x}} \]
      2. cancel-sign-sub-inv98.6%

        \[\leadsto \frac{2.6666666666666665 \cdot \color{blue}{\left(0.5 + \left(-0.5\right) \cdot \cos x\right)}}{\sin x} \]
      3. metadata-eval98.6%

        \[\leadsto \frac{2.6666666666666665 \cdot \left(0.5 + \color{blue}{-0.5} \cdot \cos x\right)}{\sin x} \]
      4. *-commutative98.6%

        \[\leadsto \frac{2.6666666666666665 \cdot \left(0.5 + \color{blue}{\cos x \cdot -0.5}\right)}{\sin x} \]
      5. +-commutative98.6%

        \[\leadsto \frac{2.6666666666666665 \cdot \color{blue}{\left(\cos x \cdot -0.5 + 0.5\right)}}{\sin x} \]
      6. distribute-rgt-in98.3%

        \[\leadsto \frac{\color{blue}{\left(\cos x \cdot -0.5\right) \cdot 2.6666666666666665 + 0.5 \cdot 2.6666666666666665}}{\sin x} \]
      7. metadata-eval98.3%

        \[\leadsto \frac{\left(\cos x \cdot -0.5\right) \cdot 2.6666666666666665 + \color{blue}{1.3333333333333333}}{\sin x} \]
      8. associate-*l*98.3%

        \[\leadsto \frac{\color{blue}{\cos x \cdot \left(-0.5 \cdot 2.6666666666666665\right)} + 1.3333333333333333}{\sin x} \]
      9. metadata-eval98.3%

        \[\leadsto \frac{\cos x \cdot \color{blue}{-1.3333333333333333} + 1.3333333333333333}{\sin x} \]
      10. metadata-eval98.3%

        \[\leadsto \frac{\cos x \cdot \color{blue}{\left(-1.3333333333333333\right)} + 1.3333333333333333}{\sin x} \]
      11. fma-def98.7%

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\cos x, -1.3333333333333333, 1.3333333333333333\right)}}{\sin x} \]
      12. metadata-eval98.7%

        \[\leadsto \frac{\mathsf{fma}\left(\cos x, \color{blue}{-1.3333333333333333}, 1.3333333333333333\right)}{\sin x} \]
    12. Simplified98.7%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\cos x, -1.3333333333333333, 1.3333333333333333\right)}{\sin x}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.0036:\\ \;\;\;\;\frac{\sin \left(x \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\cos x, -1.3333333333333333, 1.3333333333333333\right)}{\sin x}\\ \end{array} \]

Alternative 10: 99.1% accurate, 1.5× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 0.0036:\\ \;\;\;\;\frac{\sin \left(x_m \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2.6666666666666665}{\frac{\sin x_m}{0.5 + \cos x_m \cdot -0.5}}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (if (<= x_m 0.0036)
    (* (/ (sin (* x_m 0.5)) 0.375) (+ 0.5 (* (pow x_m 2.0) 0.0625)))
    (/ 2.6666666666666665 (/ (sin x_m) (+ 0.5 (* (cos x_m) -0.5)))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.0036) {
		tmp = (sin((x_m * 0.5)) / 0.375) * (0.5 + (pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = 2.6666666666666665 / (sin(x_m) / (0.5 + (cos(x_m) * -0.5)));
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 0.0036d0) then
        tmp = (sin((x_m * 0.5d0)) / 0.375d0) * (0.5d0 + ((x_m ** 2.0d0) * 0.0625d0))
    else
        tmp = 2.6666666666666665d0 / (sin(x_m) / (0.5d0 + (cos(x_m) * (-0.5d0))))
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.0036) {
		tmp = (Math.sin((x_m * 0.5)) / 0.375) * (0.5 + (Math.pow(x_m, 2.0) * 0.0625));
	} else {
		tmp = 2.6666666666666665 / (Math.sin(x_m) / (0.5 + (Math.cos(x_m) * -0.5)));
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	tmp = 0
	if x_m <= 0.0036:
		tmp = (math.sin((x_m * 0.5)) / 0.375) * (0.5 + (math.pow(x_m, 2.0) * 0.0625))
	else:
		tmp = 2.6666666666666665 / (math.sin(x_m) / (0.5 + (math.cos(x_m) * -0.5)))
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	tmp = 0.0
	if (x_m <= 0.0036)
		tmp = Float64(Float64(sin(Float64(x_m * 0.5)) / 0.375) * Float64(0.5 + Float64((x_m ^ 2.0) * 0.0625)));
	else
		tmp = Float64(2.6666666666666665 / Float64(sin(x_m) / Float64(0.5 + Float64(cos(x_m) * -0.5))));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	tmp = 0.0;
	if (x_m <= 0.0036)
		tmp = (sin((x_m * 0.5)) / 0.375) * (0.5 + ((x_m ^ 2.0) * 0.0625));
	else
		tmp = 2.6666666666666665 / (sin(x_m) / (0.5 + (cos(x_m) * -0.5)));
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[x$95$m, 0.0036], N[(N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] / 0.375), $MachinePrecision] * N[(0.5 + N[(N[Power[x$95$m, 2.0], $MachinePrecision] * 0.0625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(2.6666666666666665 / N[(N[Sin[x$95$m], $MachinePrecision] / N[(0.5 + N[(N[Cos[x$95$m], $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 0.0036:\\
\;\;\;\;\frac{\sin \left(x_m \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x_m}^{2} \cdot 0.0625\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{2.6666666666666665}{\frac{\sin x_m}{0.5 + \cos x_m \cdot -0.5}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.0035999999999999999

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 62.5%

      \[\leadsto \color{blue}{\left(0.5 + 0.0625 \cdot {x}^{2}\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    7. Step-by-step derivation
      1. *-commutative62.5%

        \[\leadsto \left(0.5 + \color{blue}{{x}^{2} \cdot 0.0625}\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
    8. Simplified62.5%

      \[\leadsto \color{blue}{\left(0.5 + {x}^{2} \cdot 0.0625\right)} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 0.0035999999999999999 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \]
      2. metadata-eval98.9%

        \[\leadsto \frac{\left(\color{blue}{\frac{8}{3}} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
      3. clear-num98.9%

        \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}}} \]
      4. associate-/r/98.9%

        \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right)} \]
      5. metadata-eval98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(\left(\color{blue}{2.6666666666666665} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right) \]
      6. associate-*l*98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \color{blue}{\left(2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)\right)} \]
      7. pow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}\right) \]
    5. Applied egg-rr98.9%

      \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot {\sin \left(x \cdot 0.5\right)}^{2}\right)} \]
    6. Step-by-step derivation
      1. unpow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)}\right) \]
      2. sin-mult98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    7. Applied egg-rr98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    8. Step-by-step derivation
      1. div-sub98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right)}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)}\right) \]
      2. +-inverses98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\cos \color{blue}{0}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      3. cos-098.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\color{blue}{1}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      4. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\color{blue}{0.5} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      5. distribute-lft-out98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{\left(x \cdot \left(0.5 + 0.5\right)\right)}}{2}\right)\right) \]
      6. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \left(x \cdot \color{blue}{1}\right)}{2}\right)\right) \]
      7. *-rgt-identity98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{x}}{2}\right)\right) \]
    9. Simplified98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(0.5 - \frac{\cos x}{2}\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*l/98.6%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos x}{2}\right)\right)}{\sin x}} \]
      2. *-un-lft-identity98.6%

        \[\leadsto \frac{\color{blue}{2.6666666666666665 \cdot \left(0.5 - \frac{\cos x}{2}\right)}}{\sin x} \]
      3. associate-/l*98.8%

        \[\leadsto \color{blue}{\frac{2.6666666666666665}{\frac{\sin x}{0.5 - \frac{\cos x}{2}}}} \]
      4. sub-neg98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{\color{blue}{0.5 + \left(-\frac{\cos x}{2}\right)}}} \]
      5. div-inv98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \left(-\color{blue}{\cos x \cdot \frac{1}{2}}\right)}} \]
      6. metadata-eval98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \left(-\cos x \cdot \color{blue}{0.5}\right)}} \]
      7. distribute-rgt-neg-in98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \color{blue}{\cos x \cdot \left(-0.5\right)}}} \]
      8. metadata-eval98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot \color{blue}{-0.5}}} \]
    11. Applied egg-rr98.8%

      \[\leadsto \color{blue}{\frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot -0.5}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.0036:\\ \;\;\;\;\frac{\sin \left(x \cdot 0.5\right)}{0.375} \cdot \left(0.5 + {x}^{2} \cdot 0.0625\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot -0.5}}\\ \end{array} \]

Alternative 11: 99.0% accurate, 1.5× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 0.000115:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;2.6666666666666665 \cdot \frac{0.5 - 0.5 \cdot \cos x_m}{\sin x_m}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (if (<= x_m 0.000115)
    (* 0.5 (/ (sin (* x_m 0.5)) 0.375))
    (* 2.6666666666666665 (/ (- 0.5 (* 0.5 (cos x_m))) (sin x_m))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.000115) {
		tmp = 0.5 * (sin((x_m * 0.5)) / 0.375);
	} else {
		tmp = 2.6666666666666665 * ((0.5 - (0.5 * cos(x_m))) / sin(x_m));
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 0.000115d0) then
        tmp = 0.5d0 * (sin((x_m * 0.5d0)) / 0.375d0)
    else
        tmp = 2.6666666666666665d0 * ((0.5d0 - (0.5d0 * cos(x_m))) / sin(x_m))
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.000115) {
		tmp = 0.5 * (Math.sin((x_m * 0.5)) / 0.375);
	} else {
		tmp = 2.6666666666666665 * ((0.5 - (0.5 * Math.cos(x_m))) / Math.sin(x_m));
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	tmp = 0
	if x_m <= 0.000115:
		tmp = 0.5 * (math.sin((x_m * 0.5)) / 0.375)
	else:
		tmp = 2.6666666666666665 * ((0.5 - (0.5 * math.cos(x_m))) / math.sin(x_m))
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	tmp = 0.0
	if (x_m <= 0.000115)
		tmp = Float64(0.5 * Float64(sin(Float64(x_m * 0.5)) / 0.375));
	else
		tmp = Float64(2.6666666666666665 * Float64(Float64(0.5 - Float64(0.5 * cos(x_m))) / sin(x_m)));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	tmp = 0.0;
	if (x_m <= 0.000115)
		tmp = 0.5 * (sin((x_m * 0.5)) / 0.375);
	else
		tmp = 2.6666666666666665 * ((0.5 - (0.5 * cos(x_m))) / sin(x_m));
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[x$95$m, 0.000115], N[(0.5 * N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] / 0.375), $MachinePrecision]), $MachinePrecision], N[(2.6666666666666665 * N[(N[(0.5 - N[(0.5 * N[Cos[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Sin[x$95$m], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 0.000115:\\
\;\;\;\;0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\\

\mathbf{else}:\\
\;\;\;\;2.6666666666666665 \cdot \frac{0.5 - 0.5 \cdot \cos x_m}{\sin x_m}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.15e-4

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 65.4%

      \[\leadsto \color{blue}{0.5} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 1.15e-4 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \]
      2. metadata-eval98.9%

        \[\leadsto \frac{\left(\color{blue}{\frac{8}{3}} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
      3. clear-num98.9%

        \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}}} \]
      4. associate-/r/98.9%

        \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right)} \]
      5. metadata-eval98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(\left(\color{blue}{2.6666666666666665} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right) \]
      6. associate-*l*98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \color{blue}{\left(2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)\right)} \]
      7. pow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}\right) \]
    5. Applied egg-rr98.9%

      \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot {\sin \left(x \cdot 0.5\right)}^{2}\right)} \]
    6. Step-by-step derivation
      1. unpow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)}\right) \]
      2. sin-mult98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    7. Applied egg-rr98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    8. Step-by-step derivation
      1. div-sub98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right)}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)}\right) \]
      2. +-inverses98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\cos \color{blue}{0}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      3. cos-098.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\color{blue}{1}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      4. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\color{blue}{0.5} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      5. distribute-lft-out98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{\left(x \cdot \left(0.5 + 0.5\right)\right)}}{2}\right)\right) \]
      6. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \left(x \cdot \color{blue}{1}\right)}{2}\right)\right) \]
      7. *-rgt-identity98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{x}}{2}\right)\right) \]
    9. Simplified98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(0.5 - \frac{\cos x}{2}\right)}\right) \]
    10. Taylor expanded in x around inf 98.6%

      \[\leadsto \color{blue}{2.6666666666666665 \cdot \frac{0.5 - 0.5 \cdot \cos x}{\sin x}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.000115:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;2.6666666666666665 \cdot \frac{0.5 - 0.5 \cdot \cos x}{\sin x}\\ \end{array} \]

Alternative 12: 99.0% accurate, 1.5× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \begin{array}{l} \mathbf{if}\;x_m \leq 0.000115:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;\frac{2.6666666666666665}{\frac{\sin x_m}{0.5 + \cos x_m \cdot -0.5}}\\ \end{array} \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (*
  x_s
  (if (<= x_m 0.000115)
    (* 0.5 (/ (sin (* x_m 0.5)) 0.375))
    (/ 2.6666666666666665 (/ (sin x_m) (+ 0.5 (* (cos x_m) -0.5)))))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.000115) {
		tmp = 0.5 * (sin((x_m * 0.5)) / 0.375);
	} else {
		tmp = 2.6666666666666665 / (sin(x_m) / (0.5 + (cos(x_m) * -0.5)));
	}
	return x_s * tmp;
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    real(8) :: tmp
    if (x_m <= 0.000115d0) then
        tmp = 0.5d0 * (sin((x_m * 0.5d0)) / 0.375d0)
    else
        tmp = 2.6666666666666665d0 / (sin(x_m) / (0.5d0 + (cos(x_m) * (-0.5d0))))
    end if
    code = x_s * tmp
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	double tmp;
	if (x_m <= 0.000115) {
		tmp = 0.5 * (Math.sin((x_m * 0.5)) / 0.375);
	} else {
		tmp = 2.6666666666666665 / (Math.sin(x_m) / (0.5 + (Math.cos(x_m) * -0.5)));
	}
	return x_s * tmp;
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	tmp = 0
	if x_m <= 0.000115:
		tmp = 0.5 * (math.sin((x_m * 0.5)) / 0.375)
	else:
		tmp = 2.6666666666666665 / (math.sin(x_m) / (0.5 + (math.cos(x_m) * -0.5)))
	return x_s * tmp
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	tmp = 0.0
	if (x_m <= 0.000115)
		tmp = Float64(0.5 * Float64(sin(Float64(x_m * 0.5)) / 0.375));
	else
		tmp = Float64(2.6666666666666665 / Float64(sin(x_m) / Float64(0.5 + Float64(cos(x_m) * -0.5))));
	end
	return Float64(x_s * tmp)
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp_2 = code(x_s, x_m)
	tmp = 0.0;
	if (x_m <= 0.000115)
		tmp = 0.5 * (sin((x_m * 0.5)) / 0.375);
	else
		tmp = 2.6666666666666665 / (sin(x_m) / (0.5 + (cos(x_m) * -0.5)));
	end
	tmp_2 = x_s * tmp;
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * If[LessEqual[x$95$m, 0.000115], N[(0.5 * N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] / 0.375), $MachinePrecision]), $MachinePrecision], N[(2.6666666666666665 / N[(N[Sin[x$95$m], $MachinePrecision] / N[(0.5 + N[(N[Cos[x$95$m], $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \begin{array}{l}
\mathbf{if}\;x_m \leq 0.000115:\\
\;\;\;\;0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\\

\mathbf{else}:\\
\;\;\;\;\frac{2.6666666666666665}{\frac{\sin x_m}{0.5 + \cos x_m \cdot -0.5}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.15e-4

    1. Initial program 68.3%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.3%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-199.3%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out99.3%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.3%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.3%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.3%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/r/99.3%

        \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
      2. *-commutative99.3%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
      3. associate-*l/99.2%

        \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
      4. associate-/r/99.2%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
      5. associate-*l/68.3%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
      6. div-inv68.5%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
      7. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
    5. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
    6. Taylor expanded in x around 0 65.4%

      \[\leadsto \color{blue}{0.5} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

    if 1.15e-4 < x

    1. Initial program 98.9%

      \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
    2. Step-by-step derivation
      1. associate-/l*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      2. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      3. *-lft-identity99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      4. metadata-eval99.0%

        \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      5. times-frac98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      6. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      7. *-commutative98.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      8. neg-mul-198.9%

        \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      9. sin-neg98.9%

        \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      10. distribute-lft-neg-out98.9%

        \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      11. times-frac99.0%

        \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
      12. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
      13. associate-/l/99.0%

        \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
      14. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
    3. Simplified99.0%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. Step-by-step derivation
      1. associate-/l*98.9%

        \[\leadsto \color{blue}{\frac{\left(2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x}} \]
      2. metadata-eval98.9%

        \[\leadsto \frac{\left(\color{blue}{\frac{8}{3}} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
      3. clear-num98.9%

        \[\leadsto \color{blue}{\frac{1}{\frac{\sin x}{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}}} \]
      4. associate-/r/98.9%

        \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right)} \]
      5. metadata-eval98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(\left(\color{blue}{2.6666666666666665} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)\right) \]
      6. associate-*l*98.9%

        \[\leadsto \frac{1}{\sin x} \cdot \color{blue}{\left(2.6666666666666665 \cdot \left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)\right)} \]
      7. pow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{{\sin \left(x \cdot 0.5\right)}^{2}}\right) \]
    5. Applied egg-rr98.9%

      \[\leadsto \color{blue}{\frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot {\sin \left(x \cdot 0.5\right)}^{2}\right)} \]
    6. Step-by-step derivation
      1. unpow298.9%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)\right)}\right) \]
      2. sin-mult98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    7. Applied egg-rr98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right) - \cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}}\right) \]
    8. Step-by-step derivation
      1. div-sub98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(\frac{\cos \left(x \cdot 0.5 - x \cdot 0.5\right)}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)}\right) \]
      2. +-inverses98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\cos \color{blue}{0}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      3. cos-098.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\frac{\color{blue}{1}}{2} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      4. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(\color{blue}{0.5} - \frac{\cos \left(x \cdot 0.5 + x \cdot 0.5\right)}{2}\right)\right) \]
      5. distribute-lft-out98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{\left(x \cdot \left(0.5 + 0.5\right)\right)}}{2}\right)\right) \]
      6. metadata-eval98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \left(x \cdot \color{blue}{1}\right)}{2}\right)\right) \]
      7. *-rgt-identity98.4%

        \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos \color{blue}{x}}{2}\right)\right) \]
    9. Simplified98.4%

      \[\leadsto \frac{1}{\sin x} \cdot \left(2.6666666666666665 \cdot \color{blue}{\left(0.5 - \frac{\cos x}{2}\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*l/98.6%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(2.6666666666666665 \cdot \left(0.5 - \frac{\cos x}{2}\right)\right)}{\sin x}} \]
      2. *-un-lft-identity98.6%

        \[\leadsto \frac{\color{blue}{2.6666666666666665 \cdot \left(0.5 - \frac{\cos x}{2}\right)}}{\sin x} \]
      3. associate-/l*98.8%

        \[\leadsto \color{blue}{\frac{2.6666666666666665}{\frac{\sin x}{0.5 - \frac{\cos x}{2}}}} \]
      4. sub-neg98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{\color{blue}{0.5 + \left(-\frac{\cos x}{2}\right)}}} \]
      5. div-inv98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \left(-\color{blue}{\cos x \cdot \frac{1}{2}}\right)}} \]
      6. metadata-eval98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \left(-\cos x \cdot \color{blue}{0.5}\right)}} \]
      7. distribute-rgt-neg-in98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \color{blue}{\cos x \cdot \left(-0.5\right)}}} \]
      8. metadata-eval98.8%

        \[\leadsto \frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot \color{blue}{-0.5}}} \]
    11. Applied egg-rr98.8%

      \[\leadsto \color{blue}{\frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot -0.5}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.000115:\\ \;\;\;\;0.5 \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}\\ \mathbf{else}:\\ \;\;\;\;\frac{2.6666666666666665}{\frac{\sin x}{0.5 + \cos x \cdot -0.5}}\\ \end{array} \]

Alternative 13: 55.5% accurate, 2.9× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \left(0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\right) \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (* x_s (* 0.5 (/ (sin (* x_m 0.5)) 0.375))))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * (0.5 * (sin((x_m * 0.5)) / 0.375));
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * (0.5d0 * (sin((x_m * 0.5d0)) / 0.375d0))
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * (0.5 * (Math.sin((x_m * 0.5)) / 0.375));
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * (0.5 * (math.sin((x_m * 0.5)) / 0.375))
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(0.5 * Float64(sin(Float64(x_m * 0.5)) / 0.375)))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * (0.5 * (sin((x_m * 0.5)) / 0.375));
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(0.5 * N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] / 0.375), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \left(0.5 \cdot \frac{\sin \left(x_m \cdot 0.5\right)}{0.375}\right)
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    3. *-lft-identity99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. metadata-eval99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    5. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    6. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    7. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    8. neg-mul-199.2%

      \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    9. sin-neg99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    10. distribute-lft-neg-out99.2%

      \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    11. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    12. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    13. associate-/l/99.2%

      \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
    14. associate-/r*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
  4. Step-by-step derivation
    1. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \cdot \sin \left(x \cdot 0.5\right)} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot 2.6666666666666665}}{\sin x} \cdot \sin \left(x \cdot 0.5\right) \]
    3. associate-*l/99.1%

      \[\leadsto \color{blue}{\left(\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot 2.6666666666666665\right)} \cdot \sin \left(x \cdot 0.5\right) \]
    4. associate-/r/99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \cdot \sin \left(x \cdot 0.5\right) \]
    5. associate-*l/75.3%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
    6. div-inv75.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \sin \left(x \cdot 0.5\right)}{\color{blue}{\sin x \cdot \frac{1}{2.6666666666666665}}} \]
    7. times-frac99.4%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{1}{2.6666666666666665}}} \]
    8. metadata-eval99.4%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{\color{blue}{0.375}} \]
  5. Applied egg-rr99.4%

    \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\sin x} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375}} \]
  6. Taylor expanded in x around 0 53.7%

    \[\leadsto \color{blue}{0.5} \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]
  7. Final simplification53.7%

    \[\leadsto 0.5 \cdot \frac{\sin \left(x \cdot 0.5\right)}{0.375} \]

Alternative 14: 55.2% accurate, 3.0× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \left(\sin \left(x_m \cdot 0.5\right) \cdot 1.3333333333333333\right) \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m)
 :precision binary64
 (* x_s (* (sin (* x_m 0.5)) 1.3333333333333333)))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * (sin((x_m * 0.5)) * 1.3333333333333333);
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * (sin((x_m * 0.5d0)) * 1.3333333333333333d0)
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * (Math.sin((x_m * 0.5)) * 1.3333333333333333);
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * (math.sin((x_m * 0.5)) * 1.3333333333333333)
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(sin(Float64(x_m * 0.5)) * 1.3333333333333333))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * (sin((x_m * 0.5)) * 1.3333333333333333);
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(N[Sin[N[(x$95$m * 0.5), $MachinePrecision]], $MachinePrecision] * 1.3333333333333333), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \left(\sin \left(x_m \cdot 0.5\right) \cdot 1.3333333333333333\right)
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. *-commutative75.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right)}}{\sin x} \]
    2. remove-double-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \color{blue}{\left(-\left(-\sin \left(x \cdot 0.5\right)\right)\right)}\right)}{\sin x} \]
    3. sin-neg75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\color{blue}{\sin \left(-x \cdot 0.5\right)}\right)\right)}{\sin x} \]
    4. distribute-lft-neg-out75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \left(\frac{8}{3} \cdot \left(-\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}\right)\right)}{\sin x} \]
    5. distribute-rgt-neg-in75.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \color{blue}{\left(-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)\right)}}{\sin x} \]
    6. associate-*r/99.2%

      \[\leadsto \color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{-\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\sin x}} \]
    7. *-commutative99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{-\color{blue}{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}}{\sin x} \]
    8. distribute-lft-neg-in99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\color{blue}{\left(-\sin \left(\left(-x\right) \cdot 0.5\right)\right) \cdot \frac{8}{3}}}{\sin x} \]
    9. distribute-lft-neg-out99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\left(-\sin \color{blue}{\left(-x \cdot 0.5\right)}\right) \cdot \frac{8}{3}}{\sin x} \]
    10. sin-neg99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\left(-\color{blue}{\left(-\sin \left(x \cdot 0.5\right)\right)}\right) \cdot \frac{8}{3}}{\sin x} \]
    11. remove-double-neg99.2%

      \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \frac{\color{blue}{\sin \left(x \cdot 0.5\right)} \cdot \frac{8}{3}}{\sin x} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{\sin \left(x \cdot 0.5\right)}{\frac{\sin x}{2.6666666666666665}}} \]
  4. Taylor expanded in x around 0 53.4%

    \[\leadsto \sin \left(x \cdot 0.5\right) \cdot \color{blue}{1.3333333333333333} \]
  5. Final simplification53.4%

    \[\leadsto \sin \left(x \cdot 0.5\right) \cdot 1.3333333333333333 \]

Alternative 15: 51.1% accurate, 104.3× speedup?

\[\begin{array}{l} x_m = \left|x\right| \\ x_s = \mathsf{copysign}\left(1, x\right) \\ x_s \cdot \left(x_m \cdot 0.6666666666666666\right) \end{array} \]
x_m = (fabs.f64 x)
x_s = (copysign.f64 1 x)
(FPCore (x_s x_m) :precision binary64 (* x_s (* x_m 0.6666666666666666)))
x_m = fabs(x);
x_s = copysign(1.0, x);
double code(double x_s, double x_m) {
	return x_s * (x_m * 0.6666666666666666);
}
x_m = abs(x)
x_s = copysign(1.0d0, x)
real(8) function code(x_s, x_m)
    real(8), intent (in) :: x_s
    real(8), intent (in) :: x_m
    code = x_s * (x_m * 0.6666666666666666d0)
end function
x_m = Math.abs(x);
x_s = Math.copySign(1.0, x);
public static double code(double x_s, double x_m) {
	return x_s * (x_m * 0.6666666666666666);
}
x_m = math.fabs(x)
x_s = math.copysign(1.0, x)
def code(x_s, x_m):
	return x_s * (x_m * 0.6666666666666666)
x_m = abs(x)
x_s = copysign(1.0, x)
function code(x_s, x_m)
	return Float64(x_s * Float64(x_m * 0.6666666666666666))
end
x_m = abs(x);
x_s = sign(x) * abs(1.0);
function tmp = code(x_s, x_m)
	tmp = x_s * (x_m * 0.6666666666666666);
end
x_m = N[Abs[x], $MachinePrecision]
x_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_] := N[(x$95$s * N[(x$95$m * 0.6666666666666666), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
x_s = \mathsf{copysign}\left(1, x\right)

\\
x_s \cdot \left(x_m \cdot 0.6666666666666666\right)
\end{array}
Derivation
  1. Initial program 75.2%

    \[\frac{\left(\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)\right) \cdot \sin \left(x \cdot 0.5\right)}{\sin x} \]
  2. Step-by-step derivation
    1. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    3. *-lft-identity99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    4. metadata-eval99.2%

      \[\leadsto \frac{\sin \left(x \cdot 0.5\right) \cdot \frac{8}{3}}{\color{blue}{\frac{-1}{-1}} \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    5. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right)}{\frac{-1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    6. associate-/l*99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(x \cdot 0.5\right) \cdot -1}{-1}} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    7. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{-1 \cdot \sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    8. neg-mul-199.2%

      \[\leadsto \frac{\color{blue}{-\sin \left(x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    9. sin-neg99.2%

      \[\leadsto \frac{\color{blue}{\sin \left(-x \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    10. distribute-lft-neg-out99.2%

      \[\leadsto \frac{\sin \color{blue}{\left(\left(-x\right) \cdot 0.5\right)}}{-1} \cdot \frac{\frac{8}{3}}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    11. times-frac99.2%

      \[\leadsto \color{blue}{\frac{\sin \left(\left(-x\right) \cdot 0.5\right) \cdot \frac{8}{3}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
    12. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}}{-1 \cdot \frac{\sin x}{\sin \left(x \cdot 0.5\right)}} \]
    13. associate-/l/99.2%

      \[\leadsto \color{blue}{\frac{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}}{-1}} \]
    14. associate-/r*99.2%

      \[\leadsto \color{blue}{\frac{\frac{8}{3} \cdot \sin \left(\left(-x\right) \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)} \cdot -1}} \]
  3. Simplified99.2%

    \[\leadsto \color{blue}{\frac{2.6666666666666665 \cdot \sin \left(x \cdot 0.5\right)}{\frac{\sin x}{\sin \left(x \cdot 0.5\right)}}} \]
  4. Taylor expanded in x around 0 49.4%

    \[\leadsto \color{blue}{0.6666666666666666 \cdot x} \]
  5. Step-by-step derivation
    1. *-commutative49.4%

      \[\leadsto \color{blue}{x \cdot 0.6666666666666666} \]
  6. Simplified49.4%

    \[\leadsto \color{blue}{x \cdot 0.6666666666666666} \]
  7. Final simplification49.4%

    \[\leadsto x \cdot 0.6666666666666666 \]

Developer target: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(x \cdot 0.5\right)\\ \frac{\frac{8 \cdot t_0}{3}}{\frac{\sin x}{t_0}} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (sin (* x 0.5)))) (/ (/ (* 8.0 t_0) 3.0) (/ (sin x) t_0))))
double code(double x) {
	double t_0 = sin((x * 0.5));
	return ((8.0 * t_0) / 3.0) / (sin(x) / t_0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = sin((x * 0.5d0))
    code = ((8.0d0 * t_0) / 3.0d0) / (sin(x) / t_0)
end function
public static double code(double x) {
	double t_0 = Math.sin((x * 0.5));
	return ((8.0 * t_0) / 3.0) / (Math.sin(x) / t_0);
}
def code(x):
	t_0 = math.sin((x * 0.5))
	return ((8.0 * t_0) / 3.0) / (math.sin(x) / t_0)
function code(x)
	t_0 = sin(Float64(x * 0.5))
	return Float64(Float64(Float64(8.0 * t_0) / 3.0) / Float64(sin(x) / t_0))
end
function tmp = code(x)
	t_0 = sin((x * 0.5));
	tmp = ((8.0 * t_0) / 3.0) / (sin(x) / t_0);
end
code[x_] := Block[{t$95$0 = N[Sin[N[(x * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(8.0 * t$95$0), $MachinePrecision] / 3.0), $MachinePrecision] / N[(N[Sin[x], $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(x \cdot 0.5\right)\\
\frac{\frac{8 \cdot t_0}{3}}{\frac{\sin x}{t_0}}
\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2023322 
(FPCore (x)
  :name "Graphics.Rasterific.Svg.PathConverter:segmentToBezier from rasterific-svg-0.2.3.1, A"
  :precision binary64

  :herbie-target
  (/ (/ (* 8.0 (sin (* x 0.5))) 3.0) (/ (sin x) (sin (* x 0.5))))

  (/ (* (* (/ 8.0 3.0) (sin (* x 0.5))) (sin (* x 0.5))) (sin x)))