2sin (example 3.3)

Percentage Accurate: 41.8% → 99.7%
Time: 13.0s
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: 41.8% 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: 99.7% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \left(-\tan \left(\frac{\varepsilon}{2}\right)\right), \sin \varepsilon \cdot \cos x\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (fma (sin x) (* (sin eps) (- (tan (/ eps 2.0)))) (* (sin eps) (cos x))))
double code(double x, double eps) {
	return fma(sin(x), (sin(eps) * -tan((eps / 2.0))), (sin(eps) * cos(x)));
}
function code(x, eps)
	return fma(sin(x), Float64(sin(eps) * Float64(-tan(Float64(eps / 2.0)))), Float64(sin(eps) * cos(x)))
end
code[x_, eps_] := N[(N[Sin[x], $MachinePrecision] * N[(N[Sin[eps], $MachinePrecision] * (-N[Tan[N[(eps / 2.0), $MachinePrecision]], $MachinePrecision])), $MachinePrecision] + N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \left(-\tan \left(\frac{\varepsilon}{2}\right)\right), \sin \varepsilon \cdot \cos x\right)
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. sin-sum63.7%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    2. associate--l+63.6%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Applied egg-rr63.6%

    \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  4. Step-by-step derivation
    1. +-commutative63.6%

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

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \left(\sin x - \sin x \cdot \cos \varepsilon\right)} \]
    3. *-commutative99.4%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} - \left(\sin x - \sin x \cdot \cos \varepsilon\right) \]
    4. *-rgt-identity99.4%

      \[\leadsto \sin \varepsilon \cdot \cos x - \left(\color{blue}{\sin x \cdot 1} - \sin x \cdot \cos \varepsilon\right) \]
    5. distribute-lft-out--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  5. Simplified99.3%

    \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  6. Taylor expanded in eps around inf 99.3%

    \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  7. Step-by-step derivation
    1. sub-neg99.3%

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon + \left(-\sin x \cdot \left(1 - \cos \varepsilon\right)\right)} \]
    2. distribute-rgt-neg-out99.3%

      \[\leadsto \cos x \cdot \sin \varepsilon + \color{blue}{\sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right)} \]
    3. *-commutative99.3%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} + \sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right) \]
    4. +-commutative99.3%

      \[\leadsto \color{blue}{\sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right) + \sin \varepsilon \cdot \cos x} \]
    5. fma-def99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, -\left(1 - \cos \varepsilon\right), \sin \varepsilon \cdot \cos x\right)} \]
    6. sub-neg99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, -\color{blue}{\left(1 + \left(-\cos \varepsilon\right)\right)}, \sin \varepsilon \cdot \cos x\right) \]
    7. +-commutative99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, -\color{blue}{\left(\left(-\cos \varepsilon\right) + 1\right)}, \sin \varepsilon \cdot \cos x\right) \]
    8. distribute-neg-in99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\left(-\left(-\cos \varepsilon\right)\right) + \left(-1\right)}, \sin \varepsilon \cdot \cos x\right) \]
    9. remove-double-neg99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\cos \varepsilon} + \left(-1\right), \sin \varepsilon \cdot \cos x\right) \]
    10. metadata-eval99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \cos \varepsilon + \color{blue}{-1}, \sin \varepsilon \cdot \cos x\right) \]
    11. *-commutative99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \cos \varepsilon + -1, \color{blue}{\cos x \cdot \sin \varepsilon}\right) \]
  8. Simplified99.4%

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

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{-1 + \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    2. flip-+99.3%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\frac{-1 \cdot -1 - \cos \varepsilon \cdot \cos \varepsilon}{-1 - \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    3. metadata-eval99.3%

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{\color{blue}{1} - \cos \varepsilon \cdot \cos \varepsilon}{-1 - \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    4. 1-sub-cos99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{\color{blue}{\sin \varepsilon \cdot \sin \varepsilon}}{-1 - \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    5. unpow299.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{\color{blue}{{\sin \varepsilon}^{2}}}{-1 - \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
  10. Applied egg-rr99.5%

    \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\frac{{\sin \varepsilon}^{2}}{-1 - \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
  11. Taylor expanded in eps around inf 99.5%

    \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{-1 \cdot \frac{{\sin \varepsilon}^{2}}{1 + \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
  12. Step-by-step derivation
    1. metadata-eval99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\frac{1}{-1}} \cdot \frac{{\sin \varepsilon}^{2}}{1 + \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    2. times-frac99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\frac{1 \cdot {\sin \varepsilon}^{2}}{-1 \cdot \left(1 + \cos \varepsilon\right)}}, \cos x \cdot \sin \varepsilon\right) \]
    3. distribute-lft-in99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{1 \cdot {\sin \varepsilon}^{2}}{\color{blue}{-1 \cdot 1 + -1 \cdot \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    4. metadata-eval99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{1 \cdot {\sin \varepsilon}^{2}}{\color{blue}{-1} + -1 \cdot \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    5. neg-mul-199.5%

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

      \[\leadsto \mathsf{fma}\left(\sin x, \frac{1 \cdot {\sin \varepsilon}^{2}}{\color{blue}{-1 - \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    7. associate-*l/99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\frac{1}{-1 - \cos \varepsilon} \cdot {\sin \varepsilon}^{2}}, \cos x \cdot \sin \varepsilon\right) \]
    8. *-commutative99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{{\sin \varepsilon}^{2} \cdot \frac{1}{-1 - \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    9. unpow299.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\left(\sin \varepsilon \cdot \sin \varepsilon\right)} \cdot \frac{1}{-1 - \cos \varepsilon}, \cos x \cdot \sin \varepsilon\right) \]
    10. associate-*r*99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon \cdot \left(\sin \varepsilon \cdot \frac{1}{-1 - \cos \varepsilon}\right)}, \cos x \cdot \sin \varepsilon\right) \]
    11. associate-*r/99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \color{blue}{\frac{\sin \varepsilon \cdot 1}{-1 - \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    12. sub-neg99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \frac{\sin \varepsilon \cdot 1}{\color{blue}{-1 + \left(-\cos \varepsilon\right)}}, \cos x \cdot \sin \varepsilon\right) \]
    13. metadata-eval99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \frac{\sin \varepsilon \cdot 1}{\color{blue}{-1 \cdot 1} + \left(-\cos \varepsilon\right)}, \cos x \cdot \sin \varepsilon\right) \]
    14. neg-mul-199.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \frac{\sin \varepsilon \cdot 1}{-1 \cdot 1 + \color{blue}{-1 \cdot \cos \varepsilon}}, \cos x \cdot \sin \varepsilon\right) \]
    15. distribute-lft-in99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \frac{\sin \varepsilon \cdot 1}{\color{blue}{-1 \cdot \left(1 + \cos \varepsilon\right)}}, \cos x \cdot \sin \varepsilon\right) \]
    16. *-commutative99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \frac{\sin \varepsilon \cdot 1}{\color{blue}{\left(1 + \cos \varepsilon\right) \cdot -1}}, \cos x \cdot \sin \varepsilon\right) \]
    17. times-frac99.5%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \color{blue}{\left(\frac{\sin \varepsilon}{1 + \cos \varepsilon} \cdot \frac{1}{-1}\right)}, \cos x \cdot \sin \varepsilon\right) \]
    18. hang-0p-tan99.6%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \left(\color{blue}{\tan \left(\frac{\varepsilon}{2}\right)} \cdot \frac{1}{-1}\right), \cos x \cdot \sin \varepsilon\right) \]
    19. metadata-eval99.6%

      \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \left(\tan \left(\frac{\varepsilon}{2}\right) \cdot \color{blue}{-1}\right), \cos x \cdot \sin \varepsilon\right) \]
  13. Simplified99.6%

    \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\sin \varepsilon \cdot \left(\tan \left(\frac{\varepsilon}{2}\right) \cdot -1\right)}, \cos x \cdot \sin \varepsilon\right) \]
  14. Final simplification99.6%

    \[\leadsto \mathsf{fma}\left(\sin x, \sin \varepsilon \cdot \left(-\tan \left(\frac{\varepsilon}{2}\right)\right), \sin \varepsilon \cdot \cos x\right) \]

Alternative 2: 76.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(x + \varepsilon\right) - \sin x\\ \mathbf{if}\;t_0 \leq -0.02 \lor \neg \left(t_0 \leq 5 \cdot 10^{-141}\right):\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\cos x \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- (sin (+ x eps)) (sin x))))
   (if (or (<= t_0 -0.02) (not (<= t_0 5e-141)))
     t_0
     (* (cos x) (* 2.0 (sin (* eps 0.5)))))))
double code(double x, double eps) {
	double t_0 = sin((x + eps)) - sin(x);
	double tmp;
	if ((t_0 <= -0.02) || !(t_0 <= 5e-141)) {
		tmp = t_0;
	} else {
		tmp = cos(x) * (2.0 * sin((eps * 0.5)));
	}
	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((x + eps)) - sin(x)
    if ((t_0 <= (-0.02d0)) .or. (.not. (t_0 <= 5d-141))) then
        tmp = t_0
    else
        tmp = cos(x) * (2.0d0 * sin((eps * 0.5d0)))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double t_0 = Math.sin((x + eps)) - Math.sin(x);
	double tmp;
	if ((t_0 <= -0.02) || !(t_0 <= 5e-141)) {
		tmp = t_0;
	} else {
		tmp = Math.cos(x) * (2.0 * Math.sin((eps * 0.5)));
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.sin((x + eps)) - math.sin(x)
	tmp = 0
	if (t_0 <= -0.02) or not (t_0 <= 5e-141):
		tmp = t_0
	else:
		tmp = math.cos(x) * (2.0 * math.sin((eps * 0.5)))
	return tmp
function code(x, eps)
	t_0 = Float64(sin(Float64(x + eps)) - sin(x))
	tmp = 0.0
	if ((t_0 <= -0.02) || !(t_0 <= 5e-141))
		tmp = t_0;
	else
		tmp = Float64(cos(x) * Float64(2.0 * sin(Float64(eps * 0.5))));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = sin((x + eps)) - sin(x);
	tmp = 0.0;
	if ((t_0 <= -0.02) || ~((t_0 <= 5e-141)))
		tmp = t_0;
	else
		tmp = cos(x) * (2.0 * sin((eps * 0.5)));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Sin[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$0, -0.02], N[Not[LessEqual[t$95$0, 5e-141]], $MachinePrecision]], t$95$0, N[(N[Cos[x], $MachinePrecision] * N[(2.0 * N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(x + \varepsilon\right) - \sin x\\
\mathbf{if}\;t_0 \leq -0.02 \lor \neg \left(t_0 \leq 5 \cdot 10^{-141}\right):\\
\;\;\;\;t_0\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < -0.0200000000000000004 or 4.9999999999999999e-141 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x))

    1. Initial program 67.4%

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

    if -0.0200000000000000004 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < 4.9999999999999999e-141

    1. Initial program 20.0%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin20.0%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv20.0%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. associate--l+20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\color{blue}{\left(x + \left(\varepsilon - x\right)\right)} \cdot \frac{1}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. metadata-eval20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      5. div-inv20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      6. +-commutative20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right) \cdot \cos \left(\left(\color{blue}{\left(\varepsilon + x\right)} + x\right) \cdot \frac{1}{2}\right)\right) \]
      7. associate-+l+20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(\varepsilon + \left(x + x\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      8. metadata-eval20.0%

        \[\leadsto 2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right) \cdot \cos \left(\left(\varepsilon + \left(x + x\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr20.0%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right) \cdot \cos \left(\left(\varepsilon + \left(x + x\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*20.0%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(\varepsilon + \left(x + x\right)\right) \cdot 0.5\right)} \]
      2. *-commutative20.0%

        \[\leadsto \color{blue}{\cos \left(\left(\varepsilon + \left(x + x\right)\right) \cdot 0.5\right) \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right)} \]
      3. *-commutative20.0%

        \[\leadsto \cos \color{blue}{\left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)} \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right) \]
      4. +-commutative20.0%

        \[\leadsto \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right) \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right) \]
      5. count-220.0%

        \[\leadsto \cos \left(0.5 \cdot \left(\color{blue}{2 \cdot x} + \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right) \]
      6. fma-def20.0%

        \[\leadsto \cos \left(0.5 \cdot \color{blue}{\mathsf{fma}\left(2, x, \varepsilon\right)}\right) \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon - x\right)\right) \cdot 0.5\right)\right) \]
      7. sub-neg20.0%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(x + \color{blue}{\left(\varepsilon + \left(-x\right)\right)}\right) \cdot 0.5\right)\right) \]
      8. mul-1-neg20.0%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(x + \left(\varepsilon + \color{blue}{-1 \cdot x}\right)\right) \cdot 0.5\right)\right) \]
      9. +-commutative20.0%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(x + \color{blue}{\left(-1 \cdot x + \varepsilon\right)}\right) \cdot 0.5\right)\right) \]
      10. associate-+r+84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\color{blue}{\left(\left(x + -1 \cdot x\right) + \varepsilon\right)} \cdot 0.5\right)\right) \]
      11. mul-1-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(\left(x + \color{blue}{\left(-x\right)}\right) + \varepsilon\right) \cdot 0.5\right)\right) \]
      12. sub-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(\color{blue}{\left(x - x\right)} + \varepsilon\right) \cdot 0.5\right)\right) \]
      13. +-inverses84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(\color{blue}{0} + \varepsilon\right) \cdot 0.5\right)\right) \]
      14. remove-double-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(0 + \color{blue}{\left(-\left(-\varepsilon\right)\right)}\right) \cdot 0.5\right)\right) \]
      15. mul-1-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(0 + \left(-\color{blue}{-1 \cdot \varepsilon}\right)\right) \cdot 0.5\right)\right) \]
      16. sub-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\color{blue}{\left(0 - -1 \cdot \varepsilon\right)} \cdot 0.5\right)\right) \]
      17. neg-sub084.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\color{blue}{\left(--1 \cdot \varepsilon\right)} \cdot 0.5\right)\right) \]
      18. mul-1-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\left(-\color{blue}{\left(-\varepsilon\right)}\right) \cdot 0.5\right)\right) \]
      19. remove-double-neg84.3%

        \[\leadsto \cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\color{blue}{\varepsilon} \cdot 0.5\right)\right) \]
    5. Simplified84.3%

      \[\leadsto \color{blue}{\cos \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \]
    6. Taylor expanded in eps around 0 84.3%

      \[\leadsto \color{blue}{\cos x} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sin \left(x + \varepsilon\right) - \sin x \leq -0.02 \lor \neg \left(\sin \left(x + \varepsilon\right) - \sin x \leq 5 \cdot 10^{-141}\right):\\ \;\;\;\;\sin \left(x + \varepsilon\right) - \sin x\\ \mathbf{else}:\\ \;\;\;\;\cos x \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)\\ \end{array} \]

Alternative 3: 99.4% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\sin \varepsilon, \cos x, \sin x \cdot \left(-1 + \cos \varepsilon\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (fma (sin eps) (cos x) (* (sin x) (+ -1.0 (cos eps)))))
double code(double x, double eps) {
	return fma(sin(eps), cos(x), (sin(x) * (-1.0 + cos(eps))));
}
function code(x, eps)
	return fma(sin(eps), cos(x), Float64(sin(x) * Float64(-1.0 + cos(eps))))
end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision] + N[(N[Sin[x], $MachinePrecision] * N[(-1.0 + N[Cos[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\sin \varepsilon, \cos x, \sin x \cdot \left(-1 + \cos \varepsilon\right)\right)
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. sin-sum63.7%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    2. associate--l+63.6%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Applied egg-rr63.6%

    \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  4. Step-by-step derivation
    1. +-commutative63.6%

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

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \left(\sin x - \sin x \cdot \cos \varepsilon\right)} \]
    3. *-commutative99.4%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} - \left(\sin x - \sin x \cdot \cos \varepsilon\right) \]
    4. *-rgt-identity99.4%

      \[\leadsto \sin \varepsilon \cdot \cos x - \left(\color{blue}{\sin x \cdot 1} - \sin x \cdot \cos \varepsilon\right) \]
    5. distribute-lft-out--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  5. Simplified99.3%

    \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  6. Taylor expanded in eps around inf 99.3%

    \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  7. Step-by-step derivation
    1. sub-neg99.3%

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon + \left(-\sin x \cdot \left(1 - \cos \varepsilon\right)\right)} \]
    2. distribute-rgt-neg-out99.3%

      \[\leadsto \cos x \cdot \sin \varepsilon + \color{blue}{\sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right)} \]
    3. *-commutative99.3%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} + \sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right) \]
    4. +-commutative99.3%

      \[\leadsto \color{blue}{\sin x \cdot \left(-\left(1 - \cos \varepsilon\right)\right) + \sin \varepsilon \cdot \cos x} \]
    5. fma-def99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, -\left(1 - \cos \varepsilon\right), \sin \varepsilon \cdot \cos x\right)} \]
    6. sub-neg99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, -\color{blue}{\left(1 + \left(-\cos \varepsilon\right)\right)}, \sin \varepsilon \cdot \cos x\right) \]
    7. +-commutative99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, -\color{blue}{\left(\left(-\cos \varepsilon\right) + 1\right)}, \sin \varepsilon \cdot \cos x\right) \]
    8. distribute-neg-in99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\left(-\left(-\cos \varepsilon\right)\right) + \left(-1\right)}, \sin \varepsilon \cdot \cos x\right) \]
    9. remove-double-neg99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \color{blue}{\cos \varepsilon} + \left(-1\right), \sin \varepsilon \cdot \cos x\right) \]
    10. metadata-eval99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \cos \varepsilon + \color{blue}{-1}, \sin \varepsilon \cdot \cos x\right) \]
    11. *-commutative99.4%

      \[\leadsto \mathsf{fma}\left(\sin x, \cos \varepsilon + -1, \color{blue}{\cos x \cdot \sin \varepsilon}\right) \]
  8. Simplified99.4%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sin x, \cos \varepsilon + -1, \cos x \cdot \sin \varepsilon\right)} \]
  9. Taylor expanded in x around inf 99.3%

    \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon + \sin x \cdot \left(\cos \varepsilon - 1\right)} \]
  10. Step-by-step derivation
    1. sub-neg99.3%

      \[\leadsto \cos x \cdot \sin \varepsilon + \sin x \cdot \color{blue}{\left(\cos \varepsilon + \left(-1\right)\right)} \]
    2. metadata-eval99.3%

      \[\leadsto \cos x \cdot \sin \varepsilon + \sin x \cdot \left(\cos \varepsilon + \color{blue}{-1}\right) \]
    3. *-commutative99.3%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} + \sin x \cdot \left(\cos \varepsilon + -1\right) \]
    4. fma-def99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sin \varepsilon, \cos x, \sin x \cdot \left(\cos \varepsilon + -1\right)\right)} \]
  11. Simplified99.4%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sin \varepsilon, \cos x, \sin x \cdot \left(\cos \varepsilon + -1\right)\right)} \]
  12. Final simplification99.4%

    \[\leadsto \mathsf{fma}\left(\sin \varepsilon, \cos x, \sin x \cdot \left(-1 + \cos \varepsilon\right)\right) \]

Alternative 4: 99.4% accurate, 0.5× speedup?

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

\\
\sin \varepsilon \cdot \cos x - \frac{\sin x}{\frac{1}{1 - \cos \varepsilon}}
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. sin-sum63.7%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    2. associate--l+63.6%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Applied egg-rr63.6%

    \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  4. Step-by-step derivation
    1. +-commutative63.6%

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

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \left(\sin x - \sin x \cdot \cos \varepsilon\right)} \]
    3. *-commutative99.4%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} - \left(\sin x - \sin x \cdot \cos \varepsilon\right) \]
    4. *-rgt-identity99.4%

      \[\leadsto \sin \varepsilon \cdot \cos x - \left(\color{blue}{\sin x \cdot 1} - \sin x \cdot \cos \varepsilon\right) \]
    5. distribute-lft-out--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  5. Simplified99.3%

    \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  6. Step-by-step derivation
    1. flip--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \sin x \cdot \color{blue}{\frac{1 \cdot 1 - \cos \varepsilon \cdot \cos \varepsilon}{1 + \cos \varepsilon}} \]
    2. associate-*r/99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\frac{\sin x \cdot \left(1 \cdot 1 - \cos \varepsilon \cdot \cos \varepsilon\right)}{1 + \cos \varepsilon}} \]
    3. metadata-eval99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x \cdot \left(\color{blue}{1} - \cos \varepsilon \cdot \cos \varepsilon\right)}{1 + \cos \varepsilon} \]
    4. 1-sub-cos99.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x \cdot \color{blue}{\left(\sin \varepsilon \cdot \sin \varepsilon\right)}}{1 + \cos \varepsilon} \]
    5. pow299.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x \cdot \color{blue}{{\sin \varepsilon}^{2}}}{1 + \cos \varepsilon} \]
  7. Applied egg-rr99.5%

    \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\frac{\sin x \cdot {\sin \varepsilon}^{2}}{1 + \cos \varepsilon}} \]
  8. Step-by-step derivation
    1. associate-/l*99.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\frac{\sin x}{\frac{1 + \cos \varepsilon}{{\sin \varepsilon}^{2}}}} \]
  9. Simplified99.5%

    \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\frac{\sin x}{\frac{1 + \cos \varepsilon}{{\sin \varepsilon}^{2}}}} \]
  10. Step-by-step derivation
    1. expm1-log1p-u99.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1 + \cos \varepsilon}{{\sin \varepsilon}^{2}}\right)\right)}} \]
    2. expm1-udef99.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{e^{\mathsf{log1p}\left(\frac{1 + \cos \varepsilon}{{\sin \varepsilon}^{2}}\right)} - 1}} \]
    3. clear-num99.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{\frac{{\sin \varepsilon}^{2}}{1 + \cos \varepsilon}}}\right)} - 1} \]
    4. unpow299.5%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{e^{\mathsf{log1p}\left(\frac{1}{\frac{\color{blue}{\sin \varepsilon \cdot \sin \varepsilon}}{1 + \cos \varepsilon}}\right)} - 1} \]
    5. 1-sub-cos99.2%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{e^{\mathsf{log1p}\left(\frac{1}{\frac{\color{blue}{1 - \cos \varepsilon \cdot \cos \varepsilon}}{1 + \cos \varepsilon}}\right)} - 1} \]
    6. metadata-eval99.2%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{e^{\mathsf{log1p}\left(\frac{1}{\frac{\color{blue}{1 \cdot 1} - \cos \varepsilon \cdot \cos \varepsilon}{1 + \cos \varepsilon}}\right)} - 1} \]
    7. flip--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 - \cos \varepsilon}}\right)} - 1} \]
  11. Applied egg-rr99.3%

    \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 - \cos \varepsilon}\right)} - 1}} \]
  12. Step-by-step derivation
    1. expm1-def99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 - \cos \varepsilon}\right)\right)}} \]
    2. expm1-log1p99.4%

      \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{\frac{1}{1 - \cos \varepsilon}}} \]
  13. Simplified99.4%

    \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\color{blue}{\frac{1}{1 - \cos \varepsilon}}} \]
  14. Final simplification99.4%

    \[\leadsto \sin \varepsilon \cdot \cos x - \frac{\sin x}{\frac{1}{1 - \cos \varepsilon}} \]

Alternative 5: 99.4% accurate, 0.5× speedup?

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

\\
\sin \varepsilon \cdot \cos x + \sin x \cdot \left(-1 + \cos \varepsilon\right)
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. sin-sum63.7%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    2. associate--l+63.6%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Applied egg-rr63.6%

    \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  4. Step-by-step derivation
    1. +-commutative63.6%

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

      \[\leadsto \color{blue}{\cos x \cdot \sin \varepsilon - \left(\sin x - \sin x \cdot \cos \varepsilon\right)} \]
    3. *-commutative99.4%

      \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x} - \left(\sin x - \sin x \cdot \cos \varepsilon\right) \]
    4. *-rgt-identity99.4%

      \[\leadsto \sin \varepsilon \cdot \cos x - \left(\color{blue}{\sin x \cdot 1} - \sin x \cdot \cos \varepsilon\right) \]
    5. distribute-lft-out--99.3%

      \[\leadsto \sin \varepsilon \cdot \cos x - \color{blue}{\sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  5. Simplified99.3%

    \[\leadsto \color{blue}{\sin \varepsilon \cdot \cos x - \sin x \cdot \left(1 - \cos \varepsilon\right)} \]
  6. Final simplification99.3%

    \[\leadsto \sin \varepsilon \cdot \cos x + \sin x \cdot \left(-1 + \cos \varepsilon\right) \]

Alternative 6: 76.3% accurate, 0.9× speedup?

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

\\
2 \cdot \left(\sin \left(\frac{\varepsilon + \left(x - x\right)}{2}\right) \cdot \cos \left(\frac{x + \left(x + \varepsilon\right)}{2}\right)\right)
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. add-cbrt-cube32.6%

      \[\leadsto \color{blue}{\sqrt[3]{\left(\sin \left(x + \varepsilon\right) \cdot \sin \left(x + \varepsilon\right)\right) \cdot \sin \left(x + \varepsilon\right)}} - \sin x \]
    2. pow332.7%

      \[\leadsto \sqrt[3]{\color{blue}{{\sin \left(x + \varepsilon\right)}^{3}}} - \sin x \]
  3. Applied egg-rr32.7%

    \[\leadsto \color{blue}{\sqrt[3]{{\sin \left(x + \varepsilon\right)}^{3}}} - \sin x \]
  4. Step-by-step derivation
    1. rem-cbrt-cube40.4%

      \[\leadsto \color{blue}{\sin \left(x + \varepsilon\right)} - \sin x \]
    2. diff-sin39.9%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    3. +-commutative39.9%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\color{blue}{\left(\varepsilon + x\right)} - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. +-commutative39.9%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right) \cdot \cos \left(\frac{\color{blue}{\left(\varepsilon + x\right)} + x}{2}\right)\right) \]
  5. Applied egg-rr39.9%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right) \cdot \cos \left(\frac{\left(\varepsilon + x\right) + x}{2}\right)\right)} \]
  6. Step-by-step derivation
    1. associate--l+76.7%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\color{blue}{\varepsilon + \left(x - x\right)}}{2}\right) \cdot \cos \left(\frac{\left(\varepsilon + x\right) + x}{2}\right)\right) \]
    2. +-commutative76.7%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\varepsilon + \left(x - x\right)}{2}\right) \cdot \cos \left(\frac{\color{blue}{x + \left(\varepsilon + x\right)}}{2}\right)\right) \]
  7. Simplified76.7%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\varepsilon + \left(x - x\right)}{2}\right) \cdot \cos \left(\frac{x + \left(\varepsilon + x\right)}{2}\right)\right)} \]
  8. Final simplification76.7%

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

Alternative 7: 76.3% accurate, 1.0× speedup?

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

\\
\cos \left(\frac{\varepsilon + x \cdot 2}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\varepsilon}{2}\right)\right)
\end{array}
Derivation
  1. Initial program 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. log1p-expm1-u40.3%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\sin \left(x + \varepsilon\right)\right)\right)} - \sin x \]
  3. Applied egg-rr40.3%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(\sin \left(x + \varepsilon\right)\right)\right)} - \sin x \]
  4. Step-by-step derivation
    1. log1p-expm1-u40.4%

      \[\leadsto \color{blue}{\sin \left(x + \varepsilon\right)} - \sin x \]
    2. diff-sin39.9%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    3. +-commutative39.9%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\color{blue}{\left(\varepsilon + x\right)} - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. +-commutative39.9%

      \[\leadsto 2 \cdot \left(\sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right) \cdot \cos \left(\frac{\color{blue}{\left(\varepsilon + x\right)} + x}{2}\right)\right) \]
  5. Applied egg-rr39.9%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right) \cdot \cos \left(\frac{\left(\varepsilon + x\right) + x}{2}\right)\right)} \]
  6. Step-by-step derivation
    1. associate-*r*39.9%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right)\right) \cdot \cos \left(\frac{\left(\varepsilon + x\right) + x}{2}\right)} \]
    2. *-commutative39.9%

      \[\leadsto \color{blue}{\cos \left(\frac{\left(\varepsilon + x\right) + x}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right)\right)} \]
    3. associate-+l+39.9%

      \[\leadsto \cos \left(\frac{\color{blue}{\varepsilon + \left(x + x\right)}}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right)\right) \]
    4. count-239.9%

      \[\leadsto \cos \left(\frac{\varepsilon + \color{blue}{2 \cdot x}}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\left(\varepsilon + x\right) - x}{2}\right)\right) \]
    5. associate--l+76.6%

      \[\leadsto \cos \left(\frac{\varepsilon + 2 \cdot x}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\color{blue}{\varepsilon + \left(x - x\right)}}{2}\right)\right) \]
    6. +-inverses76.6%

      \[\leadsto \cos \left(\frac{\varepsilon + 2 \cdot x}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\varepsilon + \color{blue}{0}}{2}\right)\right) \]
  7. Simplified76.6%

    \[\leadsto \color{blue}{\cos \left(\frac{\varepsilon + 2 \cdot x}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\varepsilon + 0}{2}\right)\right)} \]
  8. Final simplification76.6%

    \[\leadsto \cos \left(\frac{\varepsilon + x \cdot 2}{2}\right) \cdot \left(2 \cdot \sin \left(\frac{\varepsilon}{2}\right)\right) \]

Alternative 8: 76.3% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -3 \cdot 10^{-5} \lor \neg \left(\varepsilon \leq 1.12 \cdot 10^{-7}\right):\\ \;\;\;\;\sin \varepsilon\\ \mathbf{else}:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (or (<= eps -3e-5) (not (<= eps 1.12e-7))) (sin eps) (* eps (cos x))))
double code(double x, double eps) {
	double tmp;
	if ((eps <= -3e-5) || !(eps <= 1.12e-7)) {
		tmp = sin(eps);
	} else {
		tmp = eps * cos(x);
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((eps <= (-3d-5)) .or. (.not. (eps <= 1.12d-7))) then
        tmp = sin(eps)
    else
        tmp = eps * cos(x)
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((eps <= -3e-5) || !(eps <= 1.12e-7)) {
		tmp = Math.sin(eps);
	} else {
		tmp = eps * Math.cos(x);
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (eps <= -3e-5) or not (eps <= 1.12e-7):
		tmp = math.sin(eps)
	else:
		tmp = eps * math.cos(x)
	return tmp
function code(x, eps)
	tmp = 0.0
	if ((eps <= -3e-5) || !(eps <= 1.12e-7))
		tmp = sin(eps);
	else
		tmp = Float64(eps * cos(x));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((eps <= -3e-5) || ~((eps <= 1.12e-7)))
		tmp = sin(eps);
	else
		tmp = eps * cos(x);
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[Or[LessEqual[eps, -3e-5], N[Not[LessEqual[eps, 1.12e-7]], $MachinePrecision]], N[Sin[eps], $MachinePrecision], N[(eps * N[Cos[x], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -3 \cdot 10^{-5} \lor \neg \left(\varepsilon \leq 1.12 \cdot 10^{-7}\right):\\
\;\;\;\;\sin \varepsilon\\

\mathbf{else}:\\
\;\;\;\;\varepsilon \cdot \cos x\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if eps < -3.00000000000000008e-5 or 1.12e-7 < eps

    1. Initial program 52.8%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in x around 0 53.4%

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

    if -3.00000000000000008e-5 < eps < 1.12e-7

    1. Initial program 28.6%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in eps around 0 99.4%

      \[\leadsto \color{blue}{\varepsilon \cdot \cos x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -3 \cdot 10^{-5} \lor \neg \left(\varepsilon \leq 1.12 \cdot 10^{-7}\right):\\ \;\;\;\;\sin \varepsilon\\ \mathbf{else}:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \end{array} \]

Alternative 9: 55.1% 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 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Taylor expanded in x around 0 52.7%

    \[\leadsto \color{blue}{\sin \varepsilon} \]
  3. Final simplification52.7%

    \[\leadsto \sin \varepsilon \]

Alternative 10: 29.6% 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 40.4%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Taylor expanded in eps around 0 53.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \cos x} \]
  3. Taylor expanded in x around 0 28.7%

    \[\leadsto \color{blue}{\varepsilon} \]
  4. Final simplification28.7%

    \[\leadsto \varepsilon \]

Developer target: 99.4% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\sin x, \cos \varepsilon - 1, \sin \varepsilon \cdot \cos x\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (fma (sin x) (- (cos eps) 1.0) (* (sin eps) (cos x))))
double code(double x, double eps) {
	return fma(sin(x), (cos(eps) - 1.0), (sin(eps) * cos(x)));
}
function code(x, eps)
	return fma(sin(x), Float64(cos(eps) - 1.0), Float64(sin(eps) * cos(x)))
end
code[x_, eps_] := N[(N[Sin[x], $MachinePrecision] * N[(N[Cos[eps], $MachinePrecision] - 1.0), $MachinePrecision] + N[(N[Sin[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\sin x, \cos \varepsilon - 1, \sin \varepsilon \cdot \cos x\right)
\end{array}

Reproduce

?
herbie shell --seed 2023334 
(FPCore (x eps)
  :name "2sin (example 3.3)"
  :precision binary64

  :herbie-target
  (fma (sin x) (- (cos eps) 1.0) (* (sin eps) (cos x)))

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