2sin (example 3.3)

Percentage Accurate: 42.7% → 99.5%
Time: 15.9s
Alternatives: 9
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 9 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: 42.7% 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?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\ \mathsf{fma}\left(\cos \left(\varepsilon \cdot 0.5\right), \cos x, \left(-\sin x\right) \cdot t_0\right) \cdot \left(t_0 \cdot 2\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (sin (* eps 0.5))))
   (* (fma (cos (* eps 0.5)) (cos x) (* (- (sin x)) t_0)) (* t_0 2.0))))
double code(double x, double eps) {
	double t_0 = sin((eps * 0.5));
	return fma(cos((eps * 0.5)), cos(x), (-sin(x) * t_0)) * (t_0 * 2.0);
}
function code(x, eps)
	t_0 = sin(Float64(eps * 0.5))
	return Float64(fma(cos(Float64(eps * 0.5)), cos(x), Float64(Float64(-sin(x)) * t_0)) * Float64(t_0 * 2.0))
end
code[x_, eps_] := Block[{t$95$0 = N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[Cos[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * N[Cos[x], $MachinePrecision] + N[((-N[Sin[x], $MachinePrecision]) * t$95$0), $MachinePrecision]), $MachinePrecision] * N[(t$95$0 * 2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\
\mathsf{fma}\left(\cos \left(\varepsilon \cdot 0.5\right), \cos x, \left(-\sin x\right) \cdot t_0\right) \cdot \left(t_0 \cdot 2\right)
\end{array}
\end{array}
Derivation
  1. Initial program 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. diff-sin41.0%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    2. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    3. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
    5. +-commutative41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
    6. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
  3. Applied egg-rr41.0%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
  4. Step-by-step derivation
    1. associate-*r*41.0%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
    2. *-commutative41.0%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
    3. associate-*l*41.0%

      \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. +-commutative41.0%

      \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    5. associate--l+75.2%

      \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    6. +-inverses75.2%

      \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    7. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
    8. associate-+r+75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
    9. +-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
  5. Simplified75.2%

    \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. distribute-lft-in75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \varepsilon + 0.5 \cdot \left(x + x\right)\right)}\right) \]
    2. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\varepsilon \cdot 0.5} + 0.5 \cdot \left(x + x\right)\right)\right) \]
    3. +-rgt-identity75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot 0.5 + 0.5 \cdot \left(x + x\right)\right)\right) \]
    4. cos-sum99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    5. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    7. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    8. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
  7. Applied egg-rr99.5%

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
  8. Step-by-step derivation
    1. cancel-sign-sub-inv99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    2. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\color{blue}{\cos \left(0.5 \cdot \left(x + x\right)\right) \cdot \cos \left(0.5 \cdot \varepsilon\right)} + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    3. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    4. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    5. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right)\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)}\right)\right) \]
    8. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right)\right)\right) \]
    9. distribute-lft-neg-in99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\left(x + x\right) \cdot 0.5\right)\right)}\right)\right) \]
    10. fma-def99.5%

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

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)}\right) \]
  10. Taylor expanded in eps around inf 99.5%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + -1 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)\right)\right)} \]
  11. Step-by-step derivation
    1. associate-*r*99.5%

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

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
    3. distribute-rgt-neg-in99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(-\sin x\right)}\right) \]
    4. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \left(-\sin x\right)\right) \]
    5. fma-def99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(0.5 \cdot \varepsilon\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)} \]
    6. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \mathsf{fma}\left(\cos x, \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}, \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \cdot \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
  12. Simplified99.5%

    \[\leadsto \color{blue}{\left(\cos x \cdot \cos \left(\varepsilon \cdot 0.5\right) - \sin x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \]
  13. Step-by-step derivation
    1. cancel-sign-sub-inv99.5%

      \[\leadsto \color{blue}{\left(\cos x \cdot \cos \left(\varepsilon \cdot 0.5\right) + \left(-\sin x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
    2. *-commutative99.5%

      \[\leadsto \left(\color{blue}{\cos \left(\varepsilon \cdot 0.5\right) \cdot \cos x} + \left(-\sin x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
    3. fma-def99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos \left(\varepsilon \cdot 0.5\right), \cos x, \left(-\sin x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  14. Applied egg-rr99.5%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\cos \left(\varepsilon \cdot 0.5\right), \cos x, \left(-\sin x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  15. Final simplification99.5%

    \[\leadsto \mathsf{fma}\left(\cos \left(\varepsilon \cdot 0.5\right), \cos x, \left(-\sin x\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot 2\right) \]

Alternative 2: 77.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon + x\right) - \sin x\\ \mathbf{if}\;t_0 \leq -2 \cdot 10^{-7} \lor \neg \left(t_0 \leq 10^{-10}\right):\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\cos x \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot 2\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- (sin (+ eps x)) (sin x))))
   (if (or (<= t_0 -2e-7) (not (<= t_0 1e-10)))
     t_0
     (* (cos x) (* (sin (* eps 0.5)) 2.0)))))
double code(double x, double eps) {
	double t_0 = sin((eps + x)) - sin(x);
	double tmp;
	if ((t_0 <= -2e-7) || !(t_0 <= 1e-10)) {
		tmp = t_0;
	} else {
		tmp = cos(x) * (sin((eps * 0.5)) * 2.0);
	}
	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 <= (-2d-7)) .or. (.not. (t_0 <= 1d-10))) then
        tmp = t_0
    else
        tmp = cos(x) * (sin((eps * 0.5d0)) * 2.0d0)
    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 <= -2e-7) || !(t_0 <= 1e-10)) {
		tmp = t_0;
	} else {
		tmp = Math.cos(x) * (Math.sin((eps * 0.5)) * 2.0);
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.sin((eps + x)) - math.sin(x)
	tmp = 0
	if (t_0 <= -2e-7) or not (t_0 <= 1e-10):
		tmp = t_0
	else:
		tmp = math.cos(x) * (math.sin((eps * 0.5)) * 2.0)
	return tmp
function code(x, eps)
	t_0 = Float64(sin(Float64(eps + x)) - sin(x))
	tmp = 0.0
	if ((t_0 <= -2e-7) || !(t_0 <= 1e-10))
		tmp = t_0;
	else
		tmp = Float64(cos(x) * Float64(sin(Float64(eps * 0.5)) * 2.0));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = sin((eps + x)) - sin(x);
	tmp = 0.0;
	if ((t_0 <= -2e-7) || ~((t_0 <= 1e-10)))
		tmp = t_0;
	else
		tmp = cos(x) * (sin((eps * 0.5)) * 2.0);
	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[Or[LessEqual[t$95$0, -2e-7], N[Not[LessEqual[t$95$0, 1e-10]], $MachinePrecision]], t$95$0, N[(N[Cos[x], $MachinePrecision] * N[(N[Sin[N[(eps * 0.5), $MachinePrecision]], $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon + x\right) - \sin x\\
\mathbf{if}\;t_0 \leq -2 \cdot 10^{-7} \lor \neg \left(t_0 \leq 10^{-10}\right):\\
\;\;\;\;t_0\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < -1.9999999999999999e-7 or 1.00000000000000004e-10 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x))

    1. Initial program 68.0%

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

    if -1.9999999999999999e-7 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < 1.00000000000000004e-10

    1. Initial program 24.6%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Step-by-step derivation
      1. diff-sin24.6%

        \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
      2. div-inv24.6%

        \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      3. metadata-eval24.6%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
      4. div-inv24.6%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
      5. +-commutative24.6%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
      6. metadata-eval24.6%

        \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
    3. Applied egg-rr24.6%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. Step-by-step derivation
      1. associate-*r*24.6%

        \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
      2. *-commutative24.6%

        \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
      3. associate-*l*24.6%

        \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
      4. +-commutative24.6%

        \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      5. associate--l+80.6%

        \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
      6. +-inverses80.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
      8. associate-+r+80.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
    5. Simplified80.6%

      \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
    6. Step-by-step derivation
      1. distribute-lft-in80.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\varepsilon \cdot 0.5} + 0.5 \cdot \left(x + x\right)\right)\right) \]
      3. +-rgt-identity80.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot 0.5 + 0.5 \cdot \left(x + x\right)\right)\right) \]
      4. cos-sum99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
      5. +-rgt-identity99.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
      7. +-rgt-identity99.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    7. Applied egg-rr99.6%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    8. Step-by-step derivation
      1. cancel-sign-sub-inv99.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\color{blue}{\cos \left(0.5 \cdot \left(x + x\right)\right) \cdot \cos \left(0.5 \cdot \varepsilon\right)} + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
      3. count-299.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
      5. count-299.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
      6. count-299.6%

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

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)}\right)\right) \]
      8. count-299.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right)\right)\right) \]
      9. distribute-lft-neg-in99.6%

        \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\left(x + x\right) \cdot 0.5\right)\right)}\right)\right) \]
      10. fma-def99.6%

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

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

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + -1 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)\right)\right)} \]
    11. Step-by-step derivation
      1. associate-*r*99.6%

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

        \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
      3. distribute-rgt-neg-in99.6%

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

        \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \left(-\sin x\right)\right) \]
      5. fma-def99.6%

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

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

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

      \[\leadsto \color{blue}{\left(\cos x \cdot \cos \left(\varepsilon \cdot 0.5\right) - \sin x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \]
    13. Taylor expanded in eps around 0 80.6%

      \[\leadsto \color{blue}{\cos x} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.7%

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

Alternative 3: 76.8% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sin \left(\varepsilon + x\right) - \sin x\\ \mathbf{if}\;t_0 \leq -2 \cdot 10^{-7} \lor \neg \left(t_0 \leq 10^{-10}\right):\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- (sin (+ eps x)) (sin x))))
   (if (or (<= t_0 -2e-7) (not (<= t_0 1e-10))) t_0 (* eps (cos x)))))
double code(double x, double eps) {
	double t_0 = sin((eps + x)) - sin(x);
	double tmp;
	if ((t_0 <= -2e-7) || !(t_0 <= 1e-10)) {
		tmp = t_0;
	} 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) :: t_0
    real(8) :: tmp
    t_0 = sin((eps + x)) - sin(x)
    if ((t_0 <= (-2d-7)) .or. (.not. (t_0 <= 1d-10))) then
        tmp = t_0
    else
        tmp = eps * cos(x)
    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 <= -2e-7) || !(t_0 <= 1e-10)) {
		tmp = t_0;
	} else {
		tmp = eps * Math.cos(x);
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.sin((eps + x)) - math.sin(x)
	tmp = 0
	if (t_0 <= -2e-7) or not (t_0 <= 1e-10):
		tmp = t_0
	else:
		tmp = eps * math.cos(x)
	return tmp
function code(x, eps)
	t_0 = Float64(sin(Float64(eps + x)) - sin(x))
	tmp = 0.0
	if ((t_0 <= -2e-7) || !(t_0 <= 1e-10))
		tmp = t_0;
	else
		tmp = Float64(eps * cos(x));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = sin((eps + x)) - sin(x);
	tmp = 0.0;
	if ((t_0 <= -2e-7) || ~((t_0 <= 1e-10)))
		tmp = t_0;
	else
		tmp = eps * cos(x);
	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[Or[LessEqual[t$95$0, -2e-7], N[Not[LessEqual[t$95$0, 1e-10]], $MachinePrecision]], t$95$0, N[(eps * N[Cos[x], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon + x\right) - \sin x\\
\mathbf{if}\;t_0 \leq -2 \cdot 10^{-7} \lor \neg \left(t_0 \leq 10^{-10}\right):\\
\;\;\;\;t_0\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < -1.9999999999999999e-7 or 1.00000000000000004e-10 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x))

    1. Initial program 68.0%

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

    if -1.9999999999999999e-7 < (-.f64 (sin.f64 (+.f64 x eps)) (sin.f64 x)) < 1.00000000000000004e-10

    1. Initial program 24.6%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in eps around 0 78.9%

      \[\leadsto \color{blue}{\cos x \cdot \varepsilon} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.6%

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

Alternative 4: 99.5% accurate, 0.4× speedup?

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

\\
\begin{array}{l}
t_0 := \sin \left(\varepsilon \cdot 0.5\right)\\
\left(t_0 \cdot 2\right) \cdot \left(\cos \left(\varepsilon \cdot 0.5\right) \cdot \cos x - \sin x \cdot t_0\right)
\end{array}
\end{array}
Derivation
  1. Initial program 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. diff-sin41.0%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    2. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    3. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
    5. +-commutative41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
    6. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
  3. Applied egg-rr41.0%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
  4. Step-by-step derivation
    1. associate-*r*41.0%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
    2. *-commutative41.0%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
    3. associate-*l*41.0%

      \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. +-commutative41.0%

      \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    5. associate--l+75.2%

      \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    6. +-inverses75.2%

      \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    7. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
    8. associate-+r+75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
    9. +-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
  5. Simplified75.2%

    \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. distribute-lft-in75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \varepsilon + 0.5 \cdot \left(x + x\right)\right)}\right) \]
    2. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\varepsilon \cdot 0.5} + 0.5 \cdot \left(x + x\right)\right)\right) \]
    3. +-rgt-identity75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot 0.5 + 0.5 \cdot \left(x + x\right)\right)\right) \]
    4. cos-sum99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    5. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    7. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    8. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
  7. Applied egg-rr99.5%

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
  8. Step-by-step derivation
    1. cancel-sign-sub-inv99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    2. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\color{blue}{\cos \left(0.5 \cdot \left(x + x\right)\right) \cdot \cos \left(0.5 \cdot \varepsilon\right)} + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    3. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    4. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    5. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right)\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)}\right)\right) \]
    8. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right)\right)\right) \]
    9. distribute-lft-neg-in99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\left(x + x\right) \cdot 0.5\right)\right)}\right)\right) \]
    10. fma-def99.5%

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

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)}\right) \]
  10. Taylor expanded in eps around inf 99.5%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + -1 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)\right)\right)} \]
  11. Step-by-step derivation
    1. associate-*r*99.5%

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

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
    3. distribute-rgt-neg-in99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(-\sin x\right)}\right) \]
    4. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \left(-\sin x\right)\right) \]
    5. fma-def99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(0.5 \cdot \varepsilon\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)} \]
    6. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \mathsf{fma}\left(\cos x, \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}, \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \cdot \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
  12. Simplified99.5%

    \[\leadsto \color{blue}{\left(\cos x \cdot \cos \left(\varepsilon \cdot 0.5\right) - \sin x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \]
  13. Final simplification99.5%

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

Alternative 5: 99.4% accurate, 0.4× speedup?

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

\\
\mathsf{fma}\left(\cos x, \sin \varepsilon, \sin x \cdot \left(-1 + \cos \varepsilon\right)\right)
\end{array}
Derivation
  1. Initial program 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. sin-sum67.2%

      \[\leadsto \color{blue}{\left(\sin x \cdot \cos \varepsilon + \cos x \cdot \sin \varepsilon\right)} - \sin x \]
    2. associate--l+67.1%

      \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  3. Applied egg-rr67.1%

    \[\leadsto \color{blue}{\sin x \cdot \cos \varepsilon + \left(\cos x \cdot \sin \varepsilon - \sin x\right)} \]
  4. Taylor expanded in x around inf 67.2%

    \[\leadsto \color{blue}{\left(\cos x \cdot \sin \varepsilon + \cos \varepsilon \cdot \sin x\right) - \sin x} \]
  5. Step-by-step derivation
    1. associate--l+99.2%

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

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

      \[\leadsto \mathsf{fma}\left(\cos x, \sin \varepsilon, \color{blue}{\sin x \cdot \cos \varepsilon} - \sin x\right) \]
    4. *-rgt-identity99.2%

      \[\leadsto \mathsf{fma}\left(\cos x, \sin \varepsilon, \sin x \cdot \cos \varepsilon - \color{blue}{\sin x \cdot 1}\right) \]
    5. distribute-lft-out--99.2%

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

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

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

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

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

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

Alternative 6: 77.0% accurate, 1.0× speedup?

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

\\
\left(\sin \left(\varepsilon \cdot 0.5\right) \cdot 2\right) \cdot \cos \left(\varepsilon \cdot 0.5 + x\right)
\end{array}
Derivation
  1. Initial program 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Step-by-step derivation
    1. diff-sin41.0%

      \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right)} \]
    2. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \color{blue}{\left(\left(\left(x + \varepsilon\right) - x\right) \cdot \frac{1}{2}\right)} \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    3. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot \color{blue}{0.5}\right) \cdot \cos \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \]
    4. div-inv41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \color{blue}{\left(\left(\left(x + \varepsilon\right) + x\right) \cdot \frac{1}{2}\right)}\right) \]
    5. +-commutative41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\color{blue}{\left(x + \left(x + \varepsilon\right)\right)} \cdot \frac{1}{2}\right)\right) \]
    6. metadata-eval41.0%

      \[\leadsto 2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot \color{blue}{0.5}\right)\right) \]
  3. Applied egg-rr41.0%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
  4. Step-by-step derivation
    1. associate-*r*41.0%

      \[\leadsto \color{blue}{\left(2 \cdot \sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right)\right) \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)} \]
    2. *-commutative41.0%

      \[\leadsto \color{blue}{\left(\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot 2\right)} \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right) \]
    3. associate-*l*41.0%

      \[\leadsto \color{blue}{\sin \left(\left(\left(x + \varepsilon\right) - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right)} \]
    4. +-commutative41.0%

      \[\leadsto \sin \left(\left(\color{blue}{\left(\varepsilon + x\right)} - x\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    5. associate--l+75.2%

      \[\leadsto \sin \left(\color{blue}{\left(\varepsilon + \left(x - x\right)\right)} \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    6. +-inverses75.2%

      \[\leadsto \sin \left(\left(\varepsilon + \color{blue}{0}\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\left(x + \left(x + \varepsilon\right)\right) \cdot 0.5\right)\right) \]
    7. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \left(x + \left(x + \varepsilon\right)\right)\right)}\right) \]
    8. associate-+r+75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\left(x + x\right) + \varepsilon\right)}\right)\right) \]
    9. +-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \color{blue}{\left(\varepsilon + \left(x + x\right)\right)}\right)\right) \]
  5. Simplified75.2%

    \[\leadsto \color{blue}{\sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(0.5 \cdot \left(\varepsilon + \left(x + x\right)\right)\right)\right)} \]
  6. Step-by-step derivation
    1. distribute-lft-in75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \color{blue}{\left(0.5 \cdot \varepsilon + 0.5 \cdot \left(x + x\right)\right)}\right) \]
    2. *-commutative75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\varepsilon \cdot 0.5} + 0.5 \cdot \left(x + x\right)\right)\right) \]
    3. +-rgt-identity75.2%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \cos \left(\color{blue}{\left(\varepsilon + 0\right)} \cdot 0.5 + 0.5 \cdot \left(x + x\right)\right)\right) \]
    4. cos-sum99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    5. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    7. +-rgt-identity99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(\color{blue}{\varepsilon} \cdot 0.5\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    8. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \color{blue}{\left(0.5 \cdot \varepsilon\right)} \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
  7. Applied egg-rr99.5%

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) - \sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
  8. Step-by-step derivation
    1. cancel-sign-sub-inv99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\left(\cos \left(0.5 \cdot \varepsilon\right) \cdot \cos \left(0.5 \cdot \left(x + x\right)\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)}\right) \]
    2. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\color{blue}{\cos \left(0.5 \cdot \left(x + x\right)\right) \cdot \cos \left(0.5 \cdot \varepsilon\right)} + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    3. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    4. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)} \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    5. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \left(x + x\right)\right)\right)\right) \]
    6. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(0.5 \cdot \color{blue}{\left(2 \cdot x\right)}\right)\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \color{blue}{\left(\left(2 \cdot x\right) \cdot 0.5\right)}\right)\right) \]
    8. count-299.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \left(-\sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \sin \left(\color{blue}{\left(x + x\right)} \cdot 0.5\right)\right)\right) \]
    9. distribute-lft-neg-in99.5%

      \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \left(\cos \left(\left(x + x\right) \cdot 0.5\right) \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin \left(\left(x + x\right) \cdot 0.5\right)\right)}\right)\right) \]
    10. fma-def99.5%

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

    \[\leadsto \sin \left(\left(\varepsilon + 0\right) \cdot 0.5\right) \cdot \left(2 \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)}\right) \]
  10. Taylor expanded in eps around inf 99.5%

    \[\leadsto \color{blue}{2 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + -1 \cdot \left(\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)\right)\right)} \]
  11. Step-by-step derivation
    1. associate-*r*99.5%

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

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\left(-\sin \left(0.5 \cdot \varepsilon\right) \cdot \sin x\right)}\right) \]
    3. distribute-rgt-neg-in99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \color{blue}{\sin \left(0.5 \cdot \varepsilon\right) \cdot \left(-\sin x\right)}\right) \]
    4. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \left(\cos x \cdot \cos \left(0.5 \cdot \varepsilon\right) + \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)} \cdot \left(-\sin x\right)\right) \]
    5. fma-def99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(0.5 \cdot \varepsilon\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right)} \]
    6. *-commutative99.5%

      \[\leadsto \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right) \cdot \mathsf{fma}\left(\cos x, \cos \color{blue}{\left(\varepsilon \cdot 0.5\right)}, \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \]
    7. *-commutative99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos x, \cos \left(\varepsilon \cdot 0.5\right), \sin \left(\varepsilon \cdot 0.5\right) \cdot \left(-\sin x\right)\right) \cdot \left(2 \cdot \sin \left(0.5 \cdot \varepsilon\right)\right)} \]
  12. Simplified99.5%

    \[\leadsto \color{blue}{\left(\cos x \cdot \cos \left(\varepsilon \cdot 0.5\right) - \sin x \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \]
  13. Step-by-step derivation
    1. cos-sum75.2%

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon \cdot 0.5\right)} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  14. Applied egg-rr75.2%

    \[\leadsto \color{blue}{\cos \left(x + \varepsilon \cdot 0.5\right)} \cdot \left(2 \cdot \sin \left(\varepsilon \cdot 0.5\right)\right) \]
  15. Final simplification75.2%

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

Alternative 7: 76.9% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\varepsilon \leq -2.8 \cdot 10^{-5}:\\ \;\;\;\;\sin \varepsilon\\ \mathbf{elif}\;\varepsilon \leq 0.66:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<= eps -2.8e-5) (sin eps) (if (<= eps 0.66) (* eps (cos x)) (sin eps))))
double code(double x, double eps) {
	double tmp;
	if (eps <= -2.8e-5) {
		tmp = sin(eps);
	} else if (eps <= 0.66) {
		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 <= (-2.8d-5)) then
        tmp = sin(eps)
    else if (eps <= 0.66d0) 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 <= -2.8e-5) {
		tmp = Math.sin(eps);
	} else if (eps <= 0.66) {
		tmp = eps * Math.cos(x);
	} else {
		tmp = Math.sin(eps);
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if eps <= -2.8e-5:
		tmp = math.sin(eps)
	elif eps <= 0.66:
		tmp = eps * math.cos(x)
	else:
		tmp = math.sin(eps)
	return tmp
function code(x, eps)
	tmp = 0.0
	if (eps <= -2.8e-5)
		tmp = sin(eps);
	elseif (eps <= 0.66)
		tmp = Float64(eps * cos(x));
	else
		tmp = sin(eps);
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if (eps <= -2.8e-5)
		tmp = sin(eps);
	elseif (eps <= 0.66)
		tmp = eps * cos(x);
	else
		tmp = sin(eps);
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[LessEqual[eps, -2.8e-5], N[Sin[eps], $MachinePrecision], If[LessEqual[eps, 0.66], N[(eps * N[Cos[x], $MachinePrecision]), $MachinePrecision], N[Sin[eps], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\varepsilon \leq -2.8 \cdot 10^{-5}:\\
\;\;\;\;\sin \varepsilon\\

\mathbf{elif}\;\varepsilon \leq 0.66:\\
\;\;\;\;\varepsilon \cdot \cos x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if eps < -2.79999999999999996e-5 or 0.660000000000000031 < eps

    1. Initial program 51.9%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in x around 0 51.7%

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

    if -2.79999999999999996e-5 < eps < 0.660000000000000031

    1. Initial program 30.7%

      \[\sin \left(x + \varepsilon\right) - \sin x \]
    2. Taylor expanded in eps around 0 98.1%

      \[\leadsto \color{blue}{\cos x \cdot \varepsilon} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq -2.8 \cdot 10^{-5}:\\ \;\;\;\;\sin \varepsilon\\ \mathbf{elif}\;\varepsilon \leq 0.66:\\ \;\;\;\;\varepsilon \cdot \cos x\\ \mathbf{else}:\\ \;\;\;\;\sin \varepsilon\\ \end{array} \]

Alternative 8: 56.0% 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 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Taylor expanded in x around 0 52.6%

    \[\leadsto \color{blue}{\sin \varepsilon} \]
  3. Final simplification52.6%

    \[\leadsto \sin \varepsilon \]

Alternative 9: 30.3% 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 41.5%

    \[\sin \left(x + \varepsilon\right) - \sin x \]
  2. Taylor expanded in eps around 0 50.2%

    \[\leadsto \color{blue}{\cos x \cdot \varepsilon + -0.5 \cdot \left({\varepsilon}^{2} \cdot \sin x\right)} \]
  3. Step-by-step derivation
    1. fma-def50.2%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\cos x, \varepsilon, -0.5 \cdot \left({\varepsilon}^{2} \cdot \sin x\right)\right)} \]
    2. *-commutative50.2%

      \[\leadsto \mathsf{fma}\left(\cos x, \varepsilon, -0.5 \cdot \color{blue}{\left(\sin x \cdot {\varepsilon}^{2}\right)}\right) \]
    3. unpow250.2%

      \[\leadsto \mathsf{fma}\left(\cos x, \varepsilon, -0.5 \cdot \left(\sin x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
  4. Simplified50.2%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\cos x, \varepsilon, -0.5 \cdot \left(\sin x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)} \]
  5. Taylor expanded in x around 0 27.8%

    \[\leadsto \color{blue}{\varepsilon} \]
  6. Final simplification27.8%

    \[\leadsto \varepsilon \]

Developer target: 77.0% 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 2023274 
(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)))