2sin (example 3.3)

Percentage Accurate: 41.9% → 99.5%
Time: 14.2s
Alternatives: 10
Speedup: 2.0×

Specification

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

\\
\sin \left(x + \varepsilon\right) - \sin x
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 10 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 41.9% accurate, 1.0× speedup?

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

\\
\sin \left(x + \varepsilon\right) - \sin x
\end{array}

Alternative 1: 99.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -3.95 \cdot 10^{-7}:\\ \;\;\;\;\mathsf{fma}\left(\cos \varepsilon, \sin x, \mathsf{fma}\left(\sin \varepsilon, \cos x, -\sin x\right)\right)\\ \mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<= eps -3.95e-7)
   (fma (cos eps) (sin x) (fma (sin eps) (cos x) (- (sin x))))
   (if (<= eps 1.8e-8)
     (* 2.0 (* (sin (* eps 0.5)) (+ (cos x) (* (sin x) (* eps -0.5)))))
     (- (fma (sin x) (cos eps) (* (sin eps) (cos x))) (sin x)))))
double code(double x, double eps) {
	double tmp;
	if (eps <= -3.95e-7) {
		tmp = fma(cos(eps), sin(x), fma(sin(eps), cos(x), -sin(x)));
	} else if (eps <= 1.8e-8) {
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	} else {
		tmp = fma(sin(x), cos(eps), (sin(eps) * cos(x))) - sin(x);
	}
	return tmp;
}
function code(x, eps)
	tmp = 0.0
	if (eps <= -3.95e-7)
		tmp = fma(cos(eps), sin(x), fma(sin(eps), cos(x), Float64(-sin(x))));
	elseif (eps <= 1.8e-8)
		tmp = Float64(2.0 * Float64(sin(Float64(eps * 0.5)) * Float64(cos(x) + Float64(sin(x) * Float64(eps * -0.5)))));
	else
		tmp = Float64(fma(sin(x), cos(eps), Float64(sin(eps) * cos(x))) - sin(x));
	end
	return tmp
end
code[x_, eps_] := If[LessEqual[eps, -3.95e-7], N[(N[Cos[eps], $MachinePrecision] * N[Sin[x], $MachinePrecision] + N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision] + (-N[Sin[x], $MachinePrecision])), $MachinePrecision]), $MachinePrecision], If[LessEqual[eps, 1.8e-8], N[(2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[x], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Sin[x], $MachinePrecision] * N[Cos[eps], $MachinePrecision] + N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -3.95 \cdot 10^{-7}:\\
\;\;\;\;\mathsf{fma}\left(\cos \varepsilon, \sin x, \mathsf{fma}\left(\sin \varepsilon, \cos x, -\sin x\right)\right)\\

\mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\
\;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if eps < -3.94999999999999977e-7

    1. Initial program 50.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.2%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
      2. associate--l+99.2%

        \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
    3. Applied egg-rr99.2%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
    4. Step-by-step derivation
      1. *-commutative99.2%

        \[\leadsto \color{blue}{\cos \varepsilon \cdot \sin x} + \left(\cos x \cdot \sin \varepsilon - \sin x\right) \]
      2. fma-udef99.3%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\cos \varepsilon, \sin x, \cos x \cdot \sin \varepsilon - \sin x\right)} \]
      3. *-commutative99.3%

        \[\leadsto \mathsf{fma}\left(\cos \varepsilon, \sin x, \color{blue}{\sin \varepsilon \cdot \cos x} - \sin x\right) \]
      4. fma-neg99.4%

        \[\leadsto \mathsf{fma}\left(\cos \varepsilon, \sin x, \color{blue}{\mathsf{fma}\left(\sin \varepsilon, \cos x, -\sin x\right)}\right) \]
    5. Simplified99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos \varepsilon, \sin x, \mathsf{fma}\left(\sin \varepsilon, \cos x, -\sin x\right)\right)} \]

    if -3.94999999999999977e-7 < eps < 1.79999999999999991e-8

    1. Initial program 29.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin29.5%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr29.5%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*29.5%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative29.5%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*29.5%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative29.5%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+99.6%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses99.6%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + -0.5 \cdot \left(\varepsilon \cdot \sin x\right)\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*r*99.8%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \color{blue}{\left(-0.5 \cdot \varepsilon\right) \cdot \sin x}\right)\right) \]
    11. Simplified99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + \left(-0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]

    if 1.79999999999999991e-8 < eps

    1. Initial program 70.4%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.3%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
      2. fma-def99.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, \cos \varepsilon, \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    3. Applied egg-rr99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, \cos \varepsilon, \cos x \cdot \sin \varepsilon\right)} - \sin x \]
  3. Recombined 3 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -3.95 \cdot 10^{-7}:\\ \;\;\;\;\mathsf{fma}\left(\cos \varepsilon, \sin x, \mathsf{fma}\left(\sin \varepsilon, \cos x, -\sin x\right)\right)\\ \mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\ \end{array} \]

Alternative 2: 76.1% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon + x\right) - \sin x\\ \mathbf{if}\;t_0 \leq -0.01:\\ \;\;\;\;t_0\\ \mathbf{elif}\;t_0 \leq 0:\\ \;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- (sin (+ eps x)) (sin x))))
   (if (<= t_0 -0.01)
     t_0
     (if (<= t_0 0.0) (* 2.0 (* (cos x) (sin (* eps 0.5)))) (sin eps)))))
double code(double x, double eps) {
	double t_0 = sin((eps + x)) - sin(x);
	double tmp;
	if (t_0 <= -0.01) {
		tmp = t_0;
	} else if (t_0 <= 0.0) {
		tmp = 2.0 * (cos(x) * sin((eps * 0.5)));
	} else {
		tmp = sin(eps);
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sin((eps + x)) - sin(x)
    if (t_0 <= (-0.01d0)) then
        tmp = t_0
    else if (t_0 <= 0.0d0) then
        tmp = 2.0d0 * (cos(x) * sin((eps * 0.5d0)))
    else
        tmp = sin(eps)
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double t_0 = Math.sin((eps + x)) - Math.sin(x);
	double tmp;
	if (t_0 <= -0.01) {
		tmp = t_0;
	} else if (t_0 <= 0.0) {
		tmp = 2.0 * (Math.cos(x) * Math.sin((eps * 0.5)));
	} else {
		tmp = Math.sin(eps);
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.sin((eps + x)) - math.sin(x)
	tmp = 0
	if t_0 <= -0.01:
		tmp = t_0
	elif t_0 <= 0.0:
		tmp = 2.0 * (math.cos(x) * math.sin((eps * 0.5)))
	else:
		tmp = math.sin(eps)
	return tmp
function code(x, eps)
	t_0 = Float64(sin(Float64(eps + x)) - sin(x))
	tmp = 0.0
	if (t_0 <= -0.01)
		tmp = t_0;
	elseif (t_0 <= 0.0)
		tmp = Float64(2.0 * Float64(cos(x) * sin(Float64(eps * 0.5))));
	else
		tmp = sin(eps);
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = sin((eps + x)) - sin(x);
	tmp = 0.0;
	if (t_0 <= -0.01)
		tmp = t_0;
	elseif (t_0 <= 0.0)
		tmp = 2.0 * (cos(x) * sin((eps * 0.5)));
	else
		tmp = sin(eps);
	end
	tmp_2 = tmp;
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Sin[N[(eps + x), $MachinePrecision]], $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.01], t$95$0, If[LessEqual[t$95$0, 0.0], N[(2.0 * N[(N[Cos[x], $MachinePrecision] * N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sin[eps], $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon + x\right) - \sin x\\
\mathbf{if}\;t_0 \leq -0.01:\\
\;\;\;\;t_0\\

\mathbf{elif}\;t_0 \leq 0:\\
\;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\sin \varepsilon\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < -0.0100000000000000002

    1. Initial program 69.2%

      \[\sin \left(x + \varepsilon\right) - \sin x \]

    if -0.0100000000000000002 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < 0.0

    1. Initial program 16.7%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin16.7%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv16.7%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval16.7%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv16.7%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative16.7%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval16.7%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr16.7%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*16.7%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative16.7%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*16.7%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative16.7%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+82.3%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses82.3%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative82.3%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+82.3%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative82.3%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified82.3%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 82.3%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative82.3%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative82.3%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg82.3%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg82.3%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg82.3%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative82.3%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative82.3%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified82.3%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 82.3%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\cos x}\right) \]

    if 0.0 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x))

    1. Initial program 85.3%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in x around 0 85.5%

      \[\leadsto \color{blue}{\sin \varepsilon} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification80.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \left(\varepsilon + x\right) - \sin x \leq -0.01:\\ \;\;\;\;\sin \left(\varepsilon + x\right) - \sin x\\ \mathbf{elif}\;\sin \left(\varepsilon + x\right) - \sin x \leq 0:\\ \;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \]

Alternative 3: 99.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -9.8 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\ \;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (or (<= eps -9.8e-7) (not (<= eps 1.8e-8)))
   (- (fma (sin x) (cos eps) (* (sin eps) (cos x))) (sin x))
   (* 2.0 (* (sin (* eps 0.5)) (+ (cos x) (* (sin x) (* eps -0.5)))))))
double code(double x, double eps) {
	double tmp;
	if ((eps <= -9.8e-7) || !(eps <= 1.8e-8)) {
		tmp = fma(sin(x), cos(eps), (sin(eps) * cos(x))) - sin(x);
	} else {
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	}
	return tmp;
}
function code(x, eps)
	tmp = 0.0
	if ((eps <= -9.8e-7) || !(eps <= 1.8e-8))
		tmp = Float64(fma(sin(x), cos(eps), Float64(sin(eps) * cos(x))) - sin(x));
	else
		tmp = Float64(2.0 * Float64(sin(Float64(eps * 0.5)) * Float64(cos(x) + Float64(sin(x) * Float64(eps * -0.5)))));
	end
	return tmp
end
code[x_, eps_] := If[Or[LessEqual[eps, -9.8e-7], N[Not[LessEqual[eps, 1.8e-8]], $MachinePrecision]], N[(N[(N[Sin[x], $MachinePrecision] * N[Cos[eps], $MachinePrecision] + N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision], N[(2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[x], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -9.8 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\
\;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\

\mathbf{else}:\\
\;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if eps < -9.7999999999999993e-7 or 1.79999999999999991e-8 < eps

    1. Initial program 60.1%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.3%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
      2. fma-def99.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, \cos \varepsilon, \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    3. Applied egg-rr99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, \cos \varepsilon, \cos x \cdot \sin \varepsilon\right)} - \sin x \]

    if -9.7999999999999993e-7 < eps < 1.79999999999999991e-8

    1. Initial program 29.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin29.5%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr29.5%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*29.5%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative29.5%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*29.5%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative29.5%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+99.6%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses99.6%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + -0.5 \cdot \left(\varepsilon \cdot \sin x\right)\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*r*99.8%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \color{blue}{\left(-0.5 \cdot \varepsilon\right) \cdot \sin x}\right)\right) \]
    11. Simplified99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + \left(-0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -9.8 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\ \;\;\;\;\mathsf{fma}\left(\sin x, \cos \varepsilon, \sin \varepsilon \cdot \cos x\right) - \sin x\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \end{array} \]

Alternative 4: 99.5% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -4.6 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\ \;\;\;\;\cos \varepsilon \cdot \sin x + \left(\sin \varepsilon \cdot \cos x - \sin x\right)\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (or (<= eps -4.6e-7) (not (<= eps 1.8e-8)))
   (+ (* (cos eps) (sin x)) (- (* (sin eps) (cos x)) (sin x)))
   (* 2.0 (* (sin (* eps 0.5)) (+ (cos x) (* (sin x) (* eps -0.5)))))))
double code(double x, double eps) {
	double tmp;
	if ((eps <= -4.6e-7) || !(eps <= 1.8e-8)) {
		tmp = (cos(eps) * sin(x)) + ((sin(eps) * cos(x)) - sin(x));
	} else {
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((eps <= (-4.6d-7)) .or. (.not. (eps <= 1.8d-8))) then
        tmp = (cos(eps) * sin(x)) + ((sin(eps) * cos(x)) - sin(x))
    else
        tmp = 2.0d0 * (sin((eps * 0.5d0)) * (cos(x) + (sin(x) * (eps * (-0.5d0)))))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((eps <= -4.6e-7) || !(eps <= 1.8e-8)) {
		tmp = (Math.cos(eps) * Math.sin(x)) + ((Math.sin(eps) * Math.cos(x)) - Math.sin(x));
	} else {
		tmp = 2.0 * (Math.sin((eps * 0.5)) * (Math.cos(x) + (Math.sin(x) * (eps * -0.5))));
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (eps <= -4.6e-7) or not (eps <= 1.8e-8):
		tmp = (math.cos(eps) * math.sin(x)) + ((math.sin(eps) * math.cos(x)) - math.sin(x))
	else:
		tmp = 2.0 * (math.sin((eps * 0.5)) * (math.cos(x) + (math.sin(x) * (eps * -0.5))))
	return tmp
function code(x, eps)
	tmp = 0.0
	if ((eps <= -4.6e-7) || !(eps <= 1.8e-8))
		tmp = Float64(Float64(cos(eps) * sin(x)) + Float64(Float64(sin(eps) * cos(x)) - sin(x)));
	else
		tmp = Float64(2.0 * Float64(sin(Float64(eps * 0.5)) * Float64(cos(x) + Float64(sin(x) * Float64(eps * -0.5)))));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((eps <= -4.6e-7) || ~((eps <= 1.8e-8)))
		tmp = (cos(eps) * sin(x)) + ((sin(eps) * cos(x)) - sin(x));
	else
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[Or[LessEqual[eps, -4.6e-7], N[Not[LessEqual[eps, 1.8e-8]], $MachinePrecision]], N[(N[(N[Cos[eps], $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[x], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -4.6 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\
\;\;\;\;\cos \varepsilon \cdot \sin x + \left(\sin \varepsilon \cdot \cos x - \sin x\right)\\

\mathbf{else}:\\
\;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if eps < -4.5999999999999999e-7 or 1.79999999999999991e-8 < eps

    1. Initial program 60.1%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.3%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
      2. associate--l+99.3%

        \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
    3. Applied egg-rr99.3%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]

    if -4.5999999999999999e-7 < eps < 1.79999999999999991e-8

    1. Initial program 29.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin29.5%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr29.5%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*29.5%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative29.5%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*29.5%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative29.5%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+99.6%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses99.6%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + -0.5 \cdot \left(\varepsilon \cdot \sin x\right)\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*r*99.8%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \color{blue}{\left(-0.5 \cdot \varepsilon\right) \cdot \sin x}\right)\right) \]
    11. Simplified99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + \left(-0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -4.6 \cdot 10^{-7} \lor \neg \left(\varepsilon \leq 1.8 \cdot 10^{-8}\right):\\ \;\;\;\;\cos \varepsilon \cdot \sin x + \left(\sin \varepsilon \cdot \cos x - \sin x\right)\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \end{array} \]

Alternative 5: 99.5% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \varepsilon \cdot \cos x\\ t_1 := \cos \varepsilon \cdot \sin x\\ \mathbf{if}\;\varepsilon \leq -8 \cdot 10^{-7}:\\ \;\;\;\;\left(t_0 + t_1\right) - \sin x\\ \mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t_1 + \left(t_0 - \sin x\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (* (sin eps) (cos x))) (t_1 (* (cos eps) (sin x))))
   (if (<= eps -8e-7)
     (- (+ t_0 t_1) (sin x))
     (if (<= eps 1.8e-8)
       (* 2.0 (* (sin (* eps 0.5)) (+ (cos x) (* (sin x) (* eps -0.5)))))
       (+ t_1 (- t_0 (sin x)))))))
double code(double x, double eps) {
	double t_0 = sin(eps) * cos(x);
	double t_1 = cos(eps) * sin(x);
	double tmp;
	if (eps <= -8e-7) {
		tmp = (t_0 + t_1) - sin(x);
	} else if (eps <= 1.8e-8) {
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	} else {
		tmp = t_1 + (t_0 - sin(x));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = sin(eps) * cos(x)
    t_1 = cos(eps) * sin(x)
    if (eps <= (-8d-7)) then
        tmp = (t_0 + t_1) - sin(x)
    else if (eps <= 1.8d-8) then
        tmp = 2.0d0 * (sin((eps * 0.5d0)) * (cos(x) + (sin(x) * (eps * (-0.5d0)))))
    else
        tmp = t_1 + (t_0 - sin(x))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double t_0 = Math.sin(eps) * Math.cos(x);
	double t_1 = Math.cos(eps) * Math.sin(x);
	double tmp;
	if (eps <= -8e-7) {
		tmp = (t_0 + t_1) - Math.sin(x);
	} else if (eps <= 1.8e-8) {
		tmp = 2.0 * (Math.sin((eps * 0.5)) * (Math.cos(x) + (Math.sin(x) * (eps * -0.5))));
	} else {
		tmp = t_1 + (t_0 - Math.sin(x));
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.sin(eps) * math.cos(x)
	t_1 = math.cos(eps) * math.sin(x)
	tmp = 0
	if eps <= -8e-7:
		tmp = (t_0 + t_1) - math.sin(x)
	elif eps <= 1.8e-8:
		tmp = 2.0 * (math.sin((eps * 0.5)) * (math.cos(x) + (math.sin(x) * (eps * -0.5))))
	else:
		tmp = t_1 + (t_0 - math.sin(x))
	return tmp
function code(x, eps)
	t_0 = Float64(sin(eps) * cos(x))
	t_1 = Float64(cos(eps) * sin(x))
	tmp = 0.0
	if (eps <= -8e-7)
		tmp = Float64(Float64(t_0 + t_1) - sin(x));
	elseif (eps <= 1.8e-8)
		tmp = Float64(2.0 * Float64(sin(Float64(eps * 0.5)) * Float64(cos(x) + Float64(sin(x) * Float64(eps * -0.5)))));
	else
		tmp = Float64(t_1 + Float64(t_0 - sin(x)));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = sin(eps) * cos(x);
	t_1 = cos(eps) * sin(x);
	tmp = 0.0;
	if (eps <= -8e-7)
		tmp = (t_0 + t_1) - sin(x);
	elseif (eps <= 1.8e-8)
		tmp = 2.0 * (sin((eps * 0.5)) * (cos(x) + (sin(x) * (eps * -0.5))));
	else
		tmp = t_1 + (t_0 - sin(x));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[Cos[eps], $MachinePrecision] * N[Sin[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[eps, -8e-7], N[(N[(t$95$0 + t$95$1), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision], If[LessEqual[eps, 1.8e-8], N[(2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[Cos[x], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$1 + N[(t$95$0 - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \varepsilon \cdot \cos x\\
t_1 := \cos \varepsilon \cdot \sin x\\
\mathbf{if}\;\varepsilon \leq -8 \cdot 10^{-7}:\\
\;\;\;\;\left(t_0 + t_1\right) - \sin x\\

\mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\
\;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\

\mathbf{else}:\\
\;\;\;\;t_1 + \left(t_0 - \sin x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if eps < -7.9999999999999996e-7

    1. Initial program 50.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.2%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    3. Applied egg-rr99.2%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]

    if -7.9999999999999996e-7 < eps < 1.79999999999999991e-8

    1. Initial program 29.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin29.5%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval29.5%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr29.5%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*29.5%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative29.5%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*29.5%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative29.5%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+99.6%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses99.6%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg99.6%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative99.6%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified99.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + -0.5 \cdot \left(\varepsilon \cdot \sin x\right)\right)}\right) \]
    10. Step-by-step derivation
      1. associate-*r*99.8%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \color{blue}{\left(-0.5 \cdot \varepsilon\right) \cdot \sin x}\right)\right) \]
    11. Simplified99.8%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\left(\cos x + \left(-0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]

    if 1.79999999999999991e-8 < eps

    1. Initial program 70.4%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. sin-sum99.3%

        \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
      2. associate--l+99.4%

        \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
    3. Applied egg-rr99.4%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -8 \cdot 10^{-7}:\\ \;\;\;\;\left(\sin \varepsilon \cdot \cos x + \cos \varepsilon \cdot \sin x\right) - \sin x\\ \mathbf{elif}\;\varepsilon \leq 1.8 \cdot 10^{-8}:\\ \;\;\;\;2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \left(\cos x + \sin x \cdot \left(\varepsilon \cdot -0.5\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\cos \varepsilon \cdot \sin x + \left(\sin \varepsilon \cdot \cos x - \sin x\right)\\ \end{array} \]

Alternative 6: 75.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* 2.0 (* (sin (* eps 0.5)) (cos (* 0.5 (- eps (* x -2.0)))))))
double code(double x, double eps) {
	return 2.0 * (sin((eps * 0.5)) * cos((0.5 * (eps - (x * -2.0)))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = 2.0d0 * (sin((eps * 0.5d0)) * cos((0.5d0 * (eps - (x * (-2.0d0))))))
end function
public static double code(double x, double eps) {
	return 2.0 * (Math.sin((eps * 0.5)) * Math.cos((0.5 * (eps - (x * -2.0)))));
}
def code(x, eps):
	return 2.0 * (math.sin((eps * 0.5)) * math.cos((0.5 * (eps - (x * -2.0)))))
function code(x, eps)
	return Float64(2.0 * Float64(sin(Float64(eps * 0.5)) * cos(Float64(0.5 * Float64(eps - Float64(x * -2.0))))))
end
function tmp = code(x, eps)
	tmp = 2.0 * (sin((eps * 0.5)) * cos((0.5 * (eps - (x * -2.0)))));
end
code[x_, eps_] := N[(2.0 * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Cos[N[(0.5 * N[(eps - N[(x * -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)
\end{array}
Derivation
  1. Initial program 45.0%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. diff-sin44.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    2. div-inv44.6%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    3. metadata-eval44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. div-inv44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
    5. +-commutative44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
    6. metadata-eval44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
  3. Applied egg-rr44.6%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
  4. Step-by-step derivation
    1. associate-*r*44.6%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
    2. *-commutative44.6%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
    3. associate-*l*44.6%

      \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. +-commutative44.6%

      \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    5. associate--l+79.8%

      \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    6. +-inverses79.8%

      \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    7. *-commutative79.8%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
    8. associate-+r+80.0%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
    9. +-commutative80.0%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
  5. Simplified80.0%

    \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
  6. Taylor expanded in eps around inf 80.0%

    \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
  7. Step-by-step derivation
    1. *-commutative80.0%

      \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
    2. +-commutative80.0%

      \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
    3. remove-double-neg80.0%

      \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
    4. mul-1-neg80.0%

      \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
    5. sub-neg80.0%

      \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
    6. *-commutative80.0%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
    7. cancel-sign-sub-inv80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
    8. metadata-eval80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
    9. *-lft-identity80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
    10. +-commutative80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
    11. metadata-eval80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
    12. cancel-sign-sub-inv80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
    13. *-commutative80.0%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
  8. Simplified80.0%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
  9. Final simplification80.0%

    \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right) \]

Alternative 7: 76.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -0.052 \lor \neg \left(x \leq 0.00052\right):\\ \;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon + x \cdot \left(\cos \varepsilon + -1\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (or (<= x -0.052) (not (<= x 0.00052)))
   (* 2.0 (* (cos x) (sin (* eps 0.5))))
   (+ (sin eps) (* x (+ (cos eps) -1.0)))))
double code(double x, double eps) {
	double tmp;
	if ((x <= -0.052) || !(x <= 0.00052)) {
		tmp = 2.0 * (cos(x) * sin((eps * 0.5)));
	} else {
		tmp = sin(eps) + (x * (cos(eps) + -1.0));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((x <= (-0.052d0)) .or. (.not. (x <= 0.00052d0))) then
        tmp = 2.0d0 * (cos(x) * sin((eps * 0.5d0)))
    else
        tmp = sin(eps) + (x * (cos(eps) + (-1.0d0)))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((x <= -0.052) || !(x <= 0.00052)) {
		tmp = 2.0 * (Math.cos(x) * Math.sin((eps * 0.5)));
	} else {
		tmp = Math.sin(eps) + (x * (Math.cos(eps) + -1.0));
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (x <= -0.052) or not (x <= 0.00052):
		tmp = 2.0 * (math.cos(x) * math.sin((eps * 0.5)))
	else:
		tmp = math.sin(eps) + (x * (math.cos(eps) + -1.0))
	return tmp
function code(x, eps)
	tmp = 0.0
	if ((x <= -0.052) || !(x <= 0.00052))
		tmp = Float64(2.0 * Float64(cos(x) * sin(Float64(eps * 0.5))));
	else
		tmp = Float64(sin(eps) + Float64(x * Float64(cos(eps) + -1.0)));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((x <= -0.052) || ~((x <= 0.00052)))
		tmp = 2.0 * (cos(x) * sin((eps * 0.5)));
	else
		tmp = sin(eps) + (x * (cos(eps) + -1.0));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[Or[LessEqual[x, -0.052], N[Not[LessEqual[x, 0.00052]], $MachinePrecision]], N[(2.0 * N[(N[Cos[x], $MachinePrecision] * N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Sin[eps], $MachinePrecision] + N[(x * N[(N[Cos[eps], $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -0.052 \lor \neg \left(x \leq 0.00052\right):\\
\;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\sin \varepsilon + x \cdot \left(\cos \varepsilon + -1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -0.0519999999999999976 or 5.19999999999999954e-4 < x

    1. Initial program 6.5%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin5.9%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv5.9%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval5.9%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv5.9%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative5.9%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval5.9%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr5.9%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*5.9%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative5.9%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*5.9%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative5.9%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+59.2%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses59.2%

        \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      7. *-commutative59.2%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+59.5%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
      9. +-commutative59.5%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified59.5%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Taylor expanded in eps around inf 59.5%

      \[\leadsto \color{blue}{2 \cdot \left(\cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
    7. Step-by-step derivation
      1. *-commutative59.5%

        \[\leadsto 2 \cdot \color{blue}{\left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + 2 \cdot x\right)\right)\right)} \]
      2. +-commutative59.5%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \varepsilon\right)}\right)\right) \]
      3. remove-double-neg59.5%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right)\right)\right) \]
      4. mul-1-neg59.5%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right)\right)\right) \]
      5. sub-neg59.5%

        \[\leadsto 2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x - -1 \cdot \varepsilon\right)}\right)\right) \]
      6. *-commutative59.5%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \left(2 \cdot x - -1 \cdot \varepsilon\right)\right)\right) \]
      7. cancel-sign-sub-inv59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x + \left(--1\right) \cdot \varepsilon\right)}\right)\right) \]
      8. metadata-eval59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{1} \cdot \varepsilon\right)\right)\right) \]
      9. *-lft-identity59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(2 \cdot x + \color{blue}{\varepsilon}\right)\right)\right) \]
      10. +-commutative59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + 2 \cdot x\right)}\right)\right) \]
      11. metadata-eval59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon + \color{blue}{\left(--2\right)} \cdot x\right)\right)\right) \]
      12. cancel-sign-sub-inv59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon - -2 \cdot x\right)}\right)\right) \]
      13. *-commutative59.5%

        \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - \color{blue}{x \cdot -2}\right)\right)\right) \]
    8. Simplified59.5%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(\varepsilon - x \cdot -2\right)\right)\right)} \]
    9. Taylor expanded in eps around 0 59.9%

      \[\leadsto 2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \color{blue}{\cos x}\right) \]

    if -0.0519999999999999976 < x < 5.19999999999999954e-4

    1. Initial program 79.6%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in x around 0 98.9%

      \[\leadsto \color{blue}{\sin \varepsilon + x \cdot \left(\cos \varepsilon - 1\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -0.052 \lor \neg \left(x \leq 0.00052\right):\\ \;\;\;\;2 \cdot \left(\cos x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon + x \cdot \left(\cos \varepsilon + -1\right)\\ \end{array} \]

Alternative 8: 75.8% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -1.9 \cdot 10^{-6}:\\ \;\;\;\;\sin \varepsilon\\ \mathbf{elif}\;\varepsilon \leq 0.0106:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<= eps -1.9e-6)
   (sin eps)
   (if (<= eps 0.0106) (* eps (cos x)) (sin eps))))
double code(double x, double eps) {
	double tmp;
	if (eps <= -1.9e-6) {
		tmp = sin(eps);
	} else if (eps <= 0.0106) {
		tmp = eps * cos(x);
	} else {
		tmp = sin(eps);
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if (eps <= (-1.9d-6)) then
        tmp = sin(eps)
    else if (eps <= 0.0106d0) then
        tmp = eps * cos(x)
    else
        tmp = sin(eps)
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if (eps <= -1.9e-6) {
		tmp = Math.sin(eps);
	} else if (eps <= 0.0106) {
		tmp = eps * Math.cos(x);
	} else {
		tmp = Math.sin(eps);
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if eps <= -1.9e-6:
		tmp = math.sin(eps)
	elif eps <= 0.0106:
		tmp = eps * math.cos(x)
	else:
		tmp = math.sin(eps)
	return tmp
function code(x, eps)
	tmp = 0.0
	if (eps <= -1.9e-6)
		tmp = sin(eps);
	elseif (eps <= 0.0106)
		tmp = Float64(eps * cos(x));
	else
		tmp = sin(eps);
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if (eps <= -1.9e-6)
		tmp = sin(eps);
	elseif (eps <= 0.0106)
		tmp = eps * cos(x);
	else
		tmp = sin(eps);
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[LessEqual[eps, -1.9e-6], N[Sin[eps], $MachinePrecision], If[LessEqual[eps, 0.0106], N[(eps * N[Cos[x], $MachinePrecision]), $MachinePrecision], N[Sin[eps], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -1.9 \cdot 10^{-6}:\\
\;\;\;\;\sin \varepsilon\\

\mathbf{elif}\;\varepsilon \leq 0.0106:\\
\;\;\;\;\varepsilon \cdot \cos x\\

\mathbf{else}:\\
\;\;\;\;\sin \varepsilon\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if eps < -1.9e-6 or 0.0106 < eps

    1. Initial program 60.2%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in x around 0 61.2%

      \[\leadsto \color{blue}{\sin \varepsilon} \]

    if -1.9e-6 < eps < 0.0106

    1. Initial program 29.8%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in eps around 0 99.0%

      \[\leadsto \color{blue}{\varepsilon \cdot \cos x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -1.9 \cdot 10^{-6}:\\ \;\;\;\;\sin \varepsilon\\ \mathbf{elif}\;\varepsilon \leq 0.0106:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \]

Alternative 9: 55.0% accurate, 2.0× speedup?

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

\\
\sin \varepsilon
\end{array}
Derivation
  1. Initial program 45.0%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Taylor expanded in x around 0 57.2%

    \[\leadsto \color{blue}{\sin \varepsilon} \]
  3. Final simplification57.2%

    \[\leadsto \sin \varepsilon \]

Alternative 10: 28.8% accurate, 205.0× speedup?

\[\begin{array}{l} \\ \varepsilon \end{array} \]
(FPCore (x eps) :precision binary64 eps)
double code(double x, double eps) {
	return eps;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps
end function
public static double code(double x, double eps) {
	return eps;
}
def code(x, eps):
	return eps
function code(x, eps)
	return eps
end
function tmp = code(x, eps)
	tmp = eps;
end
code[x_, eps_] := eps
\begin{array}{l}

\\
\varepsilon
\end{array}
Derivation
  1. Initial program 45.0%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. diff-sin44.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    2. div-inv44.6%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    3. metadata-eval44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. div-inv44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
    5. +-commutative44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
    6. metadata-eval44.6%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
  3. Applied egg-rr44.6%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
  4. Step-by-step derivation
    1. associate-*r*44.6%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
    2. *-commutative44.6%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
    3. associate-*l*44.6%

      \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. +-commutative44.6%

      \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    5. associate--l+79.8%

      \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    6. +-inverses79.8%

      \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    7. *-commutative79.8%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
    8. associate-+r+80.0%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
    9. +-commutative80.0%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
  5. Simplified80.0%

    \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 51.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \cos x} \]
  7. Step-by-step derivation
    1. *-commutative51.1%

      \[\leadsto \color{blue}{\cos x \cdot \varepsilon} \]
  8. Simplified51.1%

    \[\leadsto \color{blue}{\cos x \cdot \varepsilon} \]
  9. Taylor expanded in x around 0 28.1%

    \[\leadsto \color{blue}{\varepsilon} \]
  10. Final simplification28.1%

    \[\leadsto \varepsilon \]

Developer target: 75.9% accurate, 1.0× speedup?

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

\\
2 \cdot \left(\cos \left(x + \frac{\varepsilon}{2}\right) \cdot \sin \left(\frac{\varepsilon}{2}\right)\right)
\end{array}

Reproduce

?
herbie shell --seed 2023297 
(FPCore (x eps)
  :name "2sin (example 3.3)"
  :precision binary64

  :herbie-target
  (* 2.0 (* (cos (+ x (/ eps 2.0))) (sin (/ eps 2.0))))

  (- (sin (+ x eps)) (sin x)))