2cos (problem 3.3.5)

Percentage Accurate: 52.5% → 99.4%
Time: 16.6s
Alternatives: 14
Speedup: 41.0×

Specification

?
\[\left(\left(-10000 \leq x \land x \leq 10000\right) \land 10^{-16} \cdot \left|x\right| < \varepsilon\right) \land \varepsilon < \left|x\right|\]
\[\begin{array}{l} \\ \cos \left(x + \varepsilon\right) - \cos x \end{array} \]
(FPCore (x eps) :precision binary64 (- (cos (+ x eps)) (cos x)))
double code(double x, double eps) {
	return cos((x + eps)) - cos(x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = cos((x + eps)) - cos(x)
end function
public static double code(double x, double eps) {
	return Math.cos((x + eps)) - Math.cos(x);
}
def code(x, eps):
	return math.cos((x + eps)) - math.cos(x)
function code(x, eps)
	return Float64(cos(Float64(x + eps)) - cos(x))
end
function tmp = code(x, eps)
	tmp = cos((x + eps)) - cos(x);
end
code[x_, eps_] := N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Cos[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\cos \left(x + \varepsilon\right) - \cos 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 14 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: 52.5% accurate, 1.0× speedup?

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

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

Alternative 1: 99.4% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(0 - \sin x, \varepsilon, \left(\varepsilon \cdot \cos x\right) \cdot \left(\varepsilon \cdot -0.5\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (fma (- 0.0 (sin x)) eps (* (* eps (cos x)) (* eps -0.5))))
double code(double x, double eps) {
	return fma((0.0 - sin(x)), eps, ((eps * cos(x)) * (eps * -0.5)));
}
function code(x, eps)
	return fma(Float64(0.0 - sin(x)), eps, Float64(Float64(eps * cos(x)) * Float64(eps * -0.5)))
end
code[x_, eps_] := N[(N[(0.0 - N[Sin[x], $MachinePrecision]), $MachinePrecision] * eps + N[(N[(eps * N[Cos[x], $MachinePrecision]), $MachinePrecision] * N[(eps * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(0 - \sin x, \varepsilon, \left(\varepsilon \cdot \cos x\right) \cdot \left(\varepsilon \cdot -0.5\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
  6. Step-by-step derivation
    1. sub-negN/A

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

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

      \[\leadsto \mathsf{+.f64}\left(\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right) \cdot \varepsilon\right), \color{blue}{\left(\left(\mathsf{neg}\left(\sin x\right)\right) \cdot \varepsilon\right)}\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \varepsilon\right), \left(\color{blue}{\left(\mathsf{neg}\left(\sin x\right)\right)} \cdot \varepsilon\right)\right) \]
    5. *-commutativeN/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\left(\left(\frac{-1}{2} \cdot \cos x\right) \cdot \varepsilon\right), \varepsilon\right), \left(\left(\mathsf{neg}\left(\color{blue}{\sin x}\right)\right) \cdot \varepsilon\right)\right) \]
    6. associate-*l*N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right), \varepsilon\right), \left(\left(\mathsf{neg}\left(\color{blue}{\sin x}\right)\right) \cdot \varepsilon\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \left(\cos x \cdot \varepsilon\right)\right), \varepsilon\right), \left(\left(\mathsf{neg}\left(\color{blue}{\sin x}\right)\right) \cdot \varepsilon\right)\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\cos x, \varepsilon\right)\right), \varepsilon\right), \left(\left(\mathsf{neg}\left(\sin x\right)\right) \cdot \varepsilon\right)\right) \]
    9. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right)\right), \varepsilon\right), \left(\left(\mathsf{neg}\left(\sin x\right)\right) \cdot \varepsilon\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right)\right), \varepsilon\right), \mathsf{*.f64}\left(\left(\mathsf{neg}\left(\sin x\right)\right), \color{blue}{\varepsilon}\right)\right) \]
    11. neg-sub0N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right)\right), \varepsilon\right), \mathsf{*.f64}\left(\left(0 - \sin x\right), \varepsilon\right)\right) \]
    12. --lowering--.f64N/A

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right)\right), \varepsilon\right), \mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, \sin x\right), \varepsilon\right)\right) \]
    13. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{+.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right)\right), \varepsilon\right), \mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon\right)\right) \]
  7. Applied egg-rr99.8%

    \[\leadsto \color{blue}{\left(-0.5 \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon + \left(0 - \sin x\right) \cdot \varepsilon} \]
  8. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \left(0 - \sin x\right) \cdot \varepsilon + \color{blue}{\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon} \]
    2. sub0-negN/A

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

      \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(\sin x\right), \color{blue}{\varepsilon}, \left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon\right) \]
    4. fma-lowering-fma.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\left(\mathsf{neg}\left(\sin x\right)\right), \color{blue}{\varepsilon}, \left(\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon\right)\right) \]
    5. sub0-negN/A

      \[\leadsto \mathsf{fma.f64}\left(\left(0 - \sin x\right), \varepsilon, \left(\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon\right)\right) \]
    6. --lowering--.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \sin x\right), \varepsilon, \left(\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon\right)\right) \]
    7. sin-lowering-sin.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \left(\left(\frac{-1}{2} \cdot \left(\cos x \cdot \varepsilon\right)\right) \cdot \varepsilon\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \left(\left(\left(\cos x \cdot \varepsilon\right) \cdot \frac{-1}{2}\right) \cdot \varepsilon\right)\right) \]
    9. associate-*l*N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \left(\left(\cos x \cdot \varepsilon\right) \cdot \left(\frac{-1}{2} \cdot \varepsilon\right)\right)\right) \]
    10. *-lowering-*.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \mathsf{*.f64}\left(\left(\cos x \cdot \varepsilon\right), \left(\frac{-1}{2} \cdot \varepsilon\right)\right)\right) \]
    11. *-lowering-*.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \mathsf{*.f64}\left(\mathsf{*.f64}\left(\cos x, \varepsilon\right), \left(\frac{-1}{2} \cdot \varepsilon\right)\right)\right) \]
    12. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right), \left(\frac{-1}{2} \cdot \varepsilon\right)\right)\right) \]
    13. *-lowering-*.f64100.0%

      \[\leadsto \mathsf{fma.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{sin.f64}\left(x\right)\right), \varepsilon, \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{cos.f64}\left(x\right), \varepsilon\right), \mathsf{*.f64}\left(\frac{-1}{2}, \varepsilon\right)\right)\right) \]
  9. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(0 - \sin x, \varepsilon, \left(\cos x \cdot \varepsilon\right) \cdot \left(-0.5 \cdot \varepsilon\right)\right)} \]
  10. Final simplification100.0%

    \[\leadsto \mathsf{fma}\left(0 - \sin x, \varepsilon, \left(\varepsilon \cdot \cos x\right) \cdot \left(\varepsilon \cdot -0.5\right)\right) \]
  11. Add Preprocessing

Alternative 2: 99.3% accurate, 1.0× speedup?

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

\\
\varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot -0.5\right) - \sin x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 \cdot \cos x\right) - \sin x\right)} \]
  6. Final simplification99.8%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \left(\cos x \cdot -0.5\right) - \sin x\right) \]
  7. Add Preprocessing

Alternative 3: 98.7% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + x \cdot \left(x \cdot \left(0.25 + x \cdot \left(x \cdot \left(-0.020833333333333332 + \left(x \cdot x\right) \cdot 0.0006944444444444445\right)\right)\right)\right)\right) - \sin x\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (-
   (*
    eps
    (+
     -0.5
     (*
      x
      (*
       x
       (+
        0.25
        (*
         x
         (*
          x
          (+ -0.020833333333333332 (* (* x x) 0.0006944444444444445)))))))))
   (sin x))))
double code(double x, double eps) {
	return eps * ((eps * (-0.5 + (x * (x * (0.25 + (x * (x * (-0.020833333333333332 + ((x * x) * 0.0006944444444444445))))))))) - sin(x));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * ((-0.5d0) + (x * (x * (0.25d0 + (x * (x * ((-0.020833333333333332d0) + ((x * x) * 0.0006944444444444445d0))))))))) - sin(x))
end function
public static double code(double x, double eps) {
	return eps * ((eps * (-0.5 + (x * (x * (0.25 + (x * (x * (-0.020833333333333332 + ((x * x) * 0.0006944444444444445))))))))) - Math.sin(x));
}
def code(x, eps):
	return eps * ((eps * (-0.5 + (x * (x * (0.25 + (x * (x * (-0.020833333333333332 + ((x * x) * 0.0006944444444444445))))))))) - math.sin(x))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * Float64(-0.5 + Float64(x * Float64(x * Float64(0.25 + Float64(x * Float64(x * Float64(-0.020833333333333332 + Float64(Float64(x * x) * 0.0006944444444444445))))))))) - sin(x)))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * (-0.5 + (x * (x * (0.25 + (x * (x * (-0.020833333333333332 + ((x * x) * 0.0006944444444444445))))))))) - sin(x));
end
code[x_, eps_] := N[(eps * N[(N[(eps * N[(-0.5 + N[(x * N[(x * N[(0.25 + N[(x * N[(x * N[(-0.020833333333333332 + N[(N[(x * x), $MachinePrecision] * 0.0006944444444444445), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + x \cdot \left(x \cdot \left(0.25 + x \cdot \left(x \cdot \left(-0.020833333333333332 + \left(x \cdot x\right) \cdot 0.0006944444444444445\right)\right)\right)\right)\right) - \sin x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right) - \frac{1}{2}\right)}\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left({x}^{2} \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    2. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left({x}^{2} \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right) + \frac{-1}{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    3. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} + {x}^{2} \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left({x}^{2} \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    5. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(\left(x \cdot x\right) \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    6. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(x \cdot \left(x \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{4} + {x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    9. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \left({x}^{2} \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    10. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \left(\left(x \cdot x\right) \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    11. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \left(x \cdot \left(x \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    12. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \left(x \cdot \left(\left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right) \cdot x\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    13. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \left(\left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right) \cdot x\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    14. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    15. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{1440} \cdot {x}^{2} - \frac{1}{48}\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    16. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{1440} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{48}\right)\right)\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    17. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{1440} \cdot {x}^{2} + \frac{-1}{48}\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    18. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{-1}{48} + \frac{1}{1440} \cdot {x}^{2}\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    19. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{48}, \left(\frac{1}{1440} \cdot {x}^{2}\right)\right)\right)\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  8. Simplified99.5%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(-0.5 + x \cdot \left(x \cdot \left(0.25 + x \cdot \left(x \cdot \left(-0.020833333333333332 + \left(x \cdot x\right) \cdot 0.0006944444444444445\right)\right)\right)\right)\right)} - \sin x\right) \]
  9. Add Preprocessing

Alternative 4: 98.8% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + \left(x \cdot x\right) \cdot \left(0.25 + x \cdot \left(x \cdot -0.020833333333333332\right)\right)\right) - \sin x\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (-
   (* eps (+ -0.5 (* (* x x) (+ 0.25 (* x (* x -0.020833333333333332))))))
   (sin x))))
double code(double x, double eps) {
	return eps * ((eps * (-0.5 + ((x * x) * (0.25 + (x * (x * -0.020833333333333332)))))) - sin(x));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * ((-0.5d0) + ((x * x) * (0.25d0 + (x * (x * (-0.020833333333333332d0))))))) - sin(x))
end function
public static double code(double x, double eps) {
	return eps * ((eps * (-0.5 + ((x * x) * (0.25 + (x * (x * -0.020833333333333332)))))) - Math.sin(x));
}
def code(x, eps):
	return eps * ((eps * (-0.5 + ((x * x) * (0.25 + (x * (x * -0.020833333333333332)))))) - math.sin(x))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * Float64(-0.5 + Float64(Float64(x * x) * Float64(0.25 + Float64(x * Float64(x * -0.020833333333333332)))))) - sin(x)))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * (-0.5 + ((x * x) * (0.25 + (x * (x * -0.020833333333333332)))))) - sin(x));
end
code[x_, eps_] := N[(eps * N[(N[(eps * N[(-0.5 + N[(N[(x * x), $MachinePrecision] * N[(0.25 + N[(x * N[(x * -0.020833333333333332), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + \left(x \cdot x\right) \cdot \left(0.25 + x \cdot \left(x \cdot -0.020833333333333332\right)\right)\right) - \sin x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right) - \frac{1}{2}\right)}\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left({x}^{2} \cdot \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    2. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left({x}^{2} \cdot \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right) + \frac{-1}{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    3. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} + {x}^{2} \cdot \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    4. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left({x}^{2} \cdot \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\left({x}^{2}\right), \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{4} + \frac{-1}{48} \cdot {x}^{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \left(\frac{-1}{48} \cdot {x}^{2}\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    9. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \left(\frac{-1}{48} \cdot \left(x \cdot x\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    10. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \left(\left(\frac{-1}{48} \cdot x\right) \cdot x\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \left(x \cdot \left(\frac{-1}{48} \cdot x\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \left(\frac{-1}{48} \cdot x\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \left(x \cdot \frac{-1}{48}\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    14. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{-1}{48}\right)\right)\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  8. Simplified99.5%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot \color{blue}{\left(-0.5 + \left(x \cdot x\right) \cdot \left(0.25 + x \cdot \left(x \cdot -0.020833333333333332\right)\right)\right)} - \sin x\right) \]
  9. Add Preprocessing

Alternative 5: 98.8% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + x \cdot \left(x \cdot 0.25\right)\right) - \sin x\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (- (* eps (+ -0.5 (* x (* x 0.25)))) (sin x))))
double code(double x, double eps) {
	return eps * ((eps * (-0.5 + (x * (x * 0.25)))) - sin(x));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * ((-0.5d0) + (x * (x * 0.25d0)))) - sin(x))
end function
public static double code(double x, double eps) {
	return eps * ((eps * (-0.5 + (x * (x * 0.25)))) - Math.sin(x));
}
def code(x, eps):
	return eps * ((eps * (-0.5 + (x * (x * 0.25)))) - math.sin(x))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * Float64(-0.5 + Float64(x * Float64(x * 0.25)))) - sin(x)))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * (-0.5 + (x * (x * 0.25)))) - sin(x));
end
code[x_, eps_] := N[(eps * N[(N[(eps * N[(-0.5 + N[(x * N[(x * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sin[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot \left(-0.5 + x \cdot \left(x \cdot 0.25\right)\right) - \sin x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\color{blue}{\left(\frac{-1}{2} \cdot \varepsilon + \frac{1}{4} \cdot \left(\varepsilon \cdot {x}^{2}\right)\right)}, \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon + \frac{1}{4} \cdot \left({x}^{2} \cdot \varepsilon\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    2. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon + \left(\frac{1}{4} \cdot {x}^{2}\right) \cdot \varepsilon\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    3. distribute-rgt-outN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} + \frac{1}{4} \cdot {x}^{2}\right)\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
    4. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{1}{4} \cdot {x}^{2} + \frac{-1}{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    5. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{1}{4} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    6. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{1}{4} \cdot {x}^{2} - \frac{1}{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{1}{4} \cdot {x}^{2} - \frac{1}{2}\right)\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
    8. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{1}{4} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    9. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{1}{4} \cdot {x}^{2} + \frac{-1}{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    10. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} + \frac{1}{4} \cdot {x}^{2}\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    11. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(\frac{1}{4} \cdot {x}^{2}\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    12. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(\frac{1}{4} \cdot \left(x \cdot x\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    13. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(\left(\frac{1}{4} \cdot x\right) \cdot x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    14. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \left(x \cdot \left(\frac{1}{4} \cdot x\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    15. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \left(\frac{1}{4} \cdot x\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    16. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \left(x \cdot \frac{1}{4}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
    17. *-lowering-*.f6499.5%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{1}{4}\right)\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  8. Simplified99.5%

    \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot \left(-0.5 + x \cdot \left(x \cdot 0.25\right)\right)} - \sin x\right) \]
  9. Add Preprocessing

Alternative 6: 98.9% accurate, 1.9× speedup?

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

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 - \sin x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\color{blue}{\left(\frac{-1}{2} \cdot \varepsilon\right)}, \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
    2. *-lowering-*.f6499.4%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
  8. Simplified99.4%

    \[\leadsto \varepsilon \cdot \left(\color{blue}{\varepsilon \cdot -0.5} - \sin x\right) \]
  9. Add Preprocessing

Alternative 7: 98.4% accurate, 7.6× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot \left(0.008333333333333333 + \left(x \cdot x\right) \cdot -0.0001984126984126984\right)\right)\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (+
   (* eps -0.5)
   (*
    x
    (-
     -1.0
     (*
      x
      (*
       x
       (+
        -0.16666666666666666
        (*
         (* x x)
         (+ 0.008333333333333333 (* (* x x) -0.0001984126984126984)))))))))))
double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * (0.008333333333333333 + ((x * x) * -0.0001984126984126984)))))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * (-0.5d0)) + (x * ((-1.0d0) - (x * (x * ((-0.16666666666666666d0) + ((x * x) * (0.008333333333333333d0 + ((x * x) * (-0.0001984126984126984d0))))))))))
end function
public static double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * (0.008333333333333333 + ((x * x) * -0.0001984126984126984)))))))));
}
def code(x, eps):
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * (0.008333333333333333 + ((x * x) * -0.0001984126984126984)))))))))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(-1.0 - Float64(x * Float64(x * Float64(-0.16666666666666666 + Float64(Float64(x * x) * Float64(0.008333333333333333 + Float64(Float64(x * x) * -0.0001984126984126984))))))))))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * (0.008333333333333333 + ((x * x) * -0.0001984126984126984)))))))));
end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(-1.0 - N[(x * N[(x * N[(-0.16666666666666666 + N[(N[(x * x), $MachinePrecision] * N[(0.008333333333333333 + N[(N[(x * x), $MachinePrecision] * -0.0001984126984126984), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot \left(0.008333333333333333 + \left(x \cdot x\right) \cdot -0.0001984126984126984\right)\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\color{blue}{\left(\frac{-1}{2} \cdot \varepsilon\right)}, \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
    2. *-lowering-*.f6499.4%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
  8. Simplified99.4%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)\right)}\right)\right) \]
  10. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)}\right)\right)\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)}\right)\right)\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \left(\color{blue}{{x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right)} - \frac{1}{6}\right)\right)\right)\right)\right)\right) \]
    4. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(x \cdot \color{blue}{\left(x \cdot \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)}\right)\right)\right)\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)}\right)\right)\right)\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) - \frac{1}{6}\right)}\right)\right)\right)\right)\right)\right) \]
    7. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}\right)\right)\right)\right)\right)\right)\right) \]
    8. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right) + \frac{-1}{6}\right)\right)\right)\right)\right)\right)\right) \]
    9. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{-1}{6} + \color{blue}{{x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right)\right) \]
    10. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right)\right)}\right)\right)\right)\right)\right)\right)\right) \]
    11. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{120} + \frac{-1}{5040} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right)\right)\right) \]
    12. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{120}} + \frac{-1}{5040} \cdot {x}^{2}\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    13. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{120}} + \frac{-1}{5040} \cdot {x}^{2}\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    14. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{120}, \color{blue}{\left(\frac{-1}{5040} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    15. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{120}, \left({x}^{2} \cdot \color{blue}{\frac{-1}{5040}}\right)\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    16. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{-1}{5040}}\right)\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    17. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{-1}{5040}\right)\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
    18. *-lowering-*.f6499.0%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{120}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{-1}{5040}\right)\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
  11. Simplified99.0%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \color{blue}{x \cdot \left(1 + x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot \left(0.008333333333333333 + \left(x \cdot x\right) \cdot -0.0001984126984126984\right)\right)\right)\right)}\right) \]
  12. Final simplification99.0%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot \left(0.008333333333333333 + \left(x \cdot x\right) \cdot -0.0001984126984126984\right)\right)\right)\right)\right) \]
  13. Add Preprocessing

Alternative 8: 98.3% accurate, 9.8× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot 0.008333333333333333\right)\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (+
   (* eps -0.5)
   (*
    x
    (-
     -1.0
     (* x (* x (+ -0.16666666666666666 (* (* x x) 0.008333333333333333)))))))))
double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * 0.008333333333333333)))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * (-0.5d0)) + (x * ((-1.0d0) - (x * (x * ((-0.16666666666666666d0) + ((x * x) * 0.008333333333333333d0)))))))
end function
public static double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * 0.008333333333333333)))))));
}
def code(x, eps):
	return eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * 0.008333333333333333)))))))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(-1.0 - Float64(x * Float64(x * Float64(-0.16666666666666666 + Float64(Float64(x * x) * 0.008333333333333333))))))))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * -0.5) + (x * (-1.0 - (x * (x * (-0.16666666666666666 + ((x * x) * 0.008333333333333333)))))));
end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(-1.0 - N[(x * N[(x * N[(-0.16666666666666666 + N[(N[(x * x), $MachinePrecision] * 0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot 0.008333333333333333\right)\right)\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\color{blue}{\left(\frac{-1}{2} \cdot \varepsilon\right)}, \mathsf{sin.f64}\left(x\right)\right)\right) \]
  7. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
    2. *-lowering-*.f6499.4%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{sin.f64}\left(\color{blue}{x}\right)\right)\right) \]
  8. Simplified99.4%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)\right)}\right)\right) \]
  10. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right)\right)\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right)\right)\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\frac{1}{120} \cdot {x}^{2}} - \frac{1}{6}\right)\right)\right)\right)\right)\right) \]
    4. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(x \cdot \color{blue}{\left(x \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right)\right)\right)\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)\right)}\right)\right)\right)\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{120} \cdot {x}^{2} - \frac{1}{6}\right)}\right)\right)\right)\right)\right)\right) \]
    7. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{120} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}\right)\right)\right)\right)\right)\right)\right) \]
    8. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{120} \cdot {x}^{2} + \frac{-1}{6}\right)\right)\right)\right)\right)\right)\right) \]
    9. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{-1}{6} + \color{blue}{\frac{1}{120} \cdot {x}^{2}}\right)\right)\right)\right)\right)\right)\right) \]
    10. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \color{blue}{\left(\frac{1}{120} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \left({x}^{2} \cdot \color{blue}{\frac{1}{120}}\right)\right)\right)\right)\right)\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{120}}\right)\right)\right)\right)\right)\right)\right)\right) \]
    13. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{120}\right)\right)\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{120}\right)\right)\right)\right)\right)\right)\right)\right) \]
  11. Simplified98.8%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 - \color{blue}{x \cdot \left(1 + x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot 0.008333333333333333\right)\right)\right)}\right) \]
  12. Final simplification98.8%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 - x \cdot \left(x \cdot \left(-0.16666666666666666 + \left(x \cdot x\right) \cdot 0.008333333333333333\right)\right)\right)\right) \]
  13. Add Preprocessing

Alternative 9: 98.3% accurate, 10.8× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666 + \varepsilon \cdot 0.25\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (+
   (* eps -0.5)
   (* x (+ -1.0 (* x (+ (* x 0.16666666666666666) (* eps 0.25))))))))
double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * ((x * 0.16666666666666666) + (eps * 0.25))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * (-0.5d0)) + (x * ((-1.0d0) + (x * ((x * 0.16666666666666666d0) + (eps * 0.25d0))))))
end function
public static double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * ((x * 0.16666666666666666) + (eps * 0.25))))));
}
def code(x, eps):
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * ((x * 0.16666666666666666) + (eps * 0.25))))))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(-1.0 + Float64(x * Float64(Float64(x * 0.16666666666666666) + Float64(eps * 0.25)))))))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * -0.5) + (x * (-1.0 + (x * ((x * 0.16666666666666666) + (eps * 0.25))))));
end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(-1.0 + N[(x * N[(N[(x * 0.16666666666666666), $MachinePrecision] + N[(eps * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666 + \varepsilon \cdot 0.25\right)\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \varepsilon + x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)}\right) \]
  7. Step-by-step derivation
    1. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon\right), \color{blue}{\left(x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)}\right)\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)\right)\right) \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)}\right)\right)\right) \]
    5. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)\right)\right) \]
    6. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) + -1\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(-1 + \color{blue}{x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \color{blue}{\left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)\right)}\right)\right)\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right)\right) \]
    10. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\left(\frac{1}{6} \cdot x\right), \color{blue}{\left(\frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right)\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\left(x \cdot \frac{1}{6}\right), \left(\color{blue}{\frac{1}{4}} \cdot \varepsilon\right)\right)\right)\right)\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \left(\color{blue}{\frac{1}{4}} \cdot \varepsilon\right)\right)\right)\right)\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \left(\varepsilon \cdot \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \mathsf{*.f64}\left(\varepsilon, \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right)\right) \]
  8. Simplified98.8%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666 + \varepsilon \cdot 0.25\right)\right)\right)} \]
  9. Add Preprocessing

Alternative 10: 98.2% accurate, 13.7× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ (* eps -0.5) (* x (+ -1.0 (* x (* x 0.16666666666666666)))))))
double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * (x * 0.16666666666666666)))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * (-0.5d0)) + (x * ((-1.0d0) + (x * (x * 0.16666666666666666d0)))))
end function
public static double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * (x * 0.16666666666666666)))));
}
def code(x, eps):
	return eps * ((eps * -0.5) + (x * (-1.0 + (x * (x * 0.16666666666666666)))))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(-1.0 + Float64(x * Float64(x * 0.16666666666666666))))))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * -0.5) + (x * (-1.0 + (x * (x * 0.16666666666666666)))));
end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(-1.0 + N[(x * N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666\right)\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \varepsilon + x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)}\right) \]
  7. Step-by-step derivation
    1. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon\right), \color{blue}{\left(x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)}\right)\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)\right)\right) \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right)\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)}\right)\right)\right) \]
    5. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)\right)\right) \]
    6. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) + -1\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(-1 + \color{blue}{x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \color{blue}{\left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)\right)}\right)\right)\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right)\right) \]
    10. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\left(\frac{1}{6} \cdot x\right), \color{blue}{\left(\frac{1}{4} \cdot \varepsilon\right)}\right)\right)\right)\right)\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\left(x \cdot \frac{1}{6}\right), \left(\color{blue}{\frac{1}{4}} \cdot \varepsilon\right)\right)\right)\right)\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \left(\color{blue}{\frac{1}{4}} \cdot \varepsilon\right)\right)\right)\right)\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \left(\varepsilon \cdot \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{6}\right), \mathsf{*.f64}\left(\varepsilon, \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right)\right) \]
  8. Simplified98.8%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \left(x \cdot 0.16666666666666666 + \varepsilon \cdot 0.25\right)\right)\right)} \]
  9. Taylor expanded in x around inf

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{6} \cdot x\right)}\right)\right)\right)\right)\right) \]
  10. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\frac{1}{6}}\right)\right)\right)\right)\right)\right) \]
    2. *-lowering-*.f6498.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\frac{1}{6}}\right)\right)\right)\right)\right)\right) \]
  11. Simplified98.8%

    \[\leadsto \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + x \cdot \color{blue}{\left(x \cdot 0.16666666666666666\right)}\right)\right) \]
  12. Add Preprocessing

Alternative 11: 97.8% accurate, 13.7× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + \varepsilon \cdot \left(x \cdot 0.25\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ (* eps -0.5) (* x (+ -1.0 (* eps (* x 0.25)))))))
double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (eps * (x * 0.25)))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((eps * (-0.5d0)) + (x * ((-1.0d0) + (eps * (x * 0.25d0)))))
end function
public static double code(double x, double eps) {
	return eps * ((eps * -0.5) + (x * (-1.0 + (eps * (x * 0.25)))));
}
def code(x, eps):
	return eps * ((eps * -0.5) + (x * (-1.0 + (eps * (x * 0.25)))))
function code(x, eps)
	return Float64(eps * Float64(Float64(eps * -0.5) + Float64(x * Float64(-1.0 + Float64(eps * Float64(x * 0.25))))))
end
function tmp = code(x, eps)
	tmp = eps * ((eps * -0.5) + (x * (-1.0 + (eps * (x * 0.25)))));
end
code[x_, eps_] := N[(eps * N[(N[(eps * -0.5), $MachinePrecision] + N[(x * N[(-1.0 + N[(eps * N[(x * 0.25), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + \varepsilon \cdot \left(x \cdot 0.25\right)\right)\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \varepsilon + x \cdot \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)\right)}\right) \]
  7. Step-by-step derivation
    1. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon\right), \color{blue}{\left(x \cdot \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)\right)}\right)\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)\right)\right)\right) \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \left(\color{blue}{x} \cdot \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)\right)\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) - 1\right)}\right)\right)\right) \]
    5. sub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)\right)\right) \]
    6. metadata-evalN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right) + -1\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \left(-1 + \color{blue}{\frac{1}{4} \cdot \left(\varepsilon \cdot x\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \color{blue}{\left(\frac{1}{4} \cdot \left(\varepsilon \cdot x\right)\right)}\right)\right)\right)\right) \]
    9. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \left(\left(\frac{1}{4} \cdot \varepsilon\right) \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
    10. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \left(\left(\varepsilon \cdot \frac{1}{4}\right) \cdot x\right)\right)\right)\right)\right) \]
    11. associate-*l*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \left(\varepsilon \cdot \color{blue}{\left(\frac{1}{4} \cdot x\right)}\right)\right)\right)\right)\right) \]
    12. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{1}{4} \cdot x\right)}\right)\right)\right)\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(\varepsilon, \left(x \cdot \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right) \]
    14. *-lowering-*.f6498.2%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{+.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(-1, \mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(x, \color{blue}{\frac{1}{4}}\right)\right)\right)\right)\right)\right) \]
  8. Simplified98.2%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(\varepsilon \cdot -0.5 + x \cdot \left(-1 + \varepsilon \cdot \left(x \cdot 0.25\right)\right)\right)} \]
  9. Add Preprocessing

Alternative 12: 97.8% accurate, 29.3× speedup?

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

\\
\varepsilon \cdot \left(\varepsilon \cdot -0.5 - x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

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

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(\frac{-1}{2} \cdot \left(\varepsilon \cdot \cos x\right) - \sin x\right)}\right) \]
    2. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\left(\varepsilon \cdot \cos x\right) \cdot \frac{-1}{2} - \sin \color{blue}{x}\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\cos x \cdot \frac{-1}{2}\right) - \sin \color{blue}{x}\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right) - \sin x\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \left(\frac{-1}{2} \cdot \cos x\right)\right), \color{blue}{\sin x}\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \cos x\right)\right), \sin \color{blue}{x}\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \cos x\right)\right), \sin x\right)\right) \]
    8. cos-lowering-cos.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \sin x\right)\right) \]
    9. sin-lowering-sin.f6499.8%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \mathsf{*.f64}\left(\frac{-1}{2}, \mathsf{cos.f64}\left(x\right)\right)\right), \mathsf{sin.f64}\left(x\right)\right)\right) \]
  5. Simplified99.8%

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

    \[\leadsto \color{blue}{-1 \cdot \left(\varepsilon \cdot x\right) + \frac{-1}{2} \cdot {\varepsilon}^{2}} \]
  7. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \left(\mathsf{neg}\left(\varepsilon \cdot x\right)\right) + \color{blue}{\frac{-1}{2}} \cdot {\varepsilon}^{2} \]
    2. *-commutativeN/A

      \[\leadsto \left(\mathsf{neg}\left(x \cdot \varepsilon\right)\right) + \frac{-1}{2} \cdot {\varepsilon}^{2} \]
    3. distribute-lft-neg-inN/A

      \[\leadsto \left(\mathsf{neg}\left(x\right)\right) \cdot \varepsilon + \color{blue}{\frac{-1}{2}} \cdot {\varepsilon}^{2} \]
    4. mul-1-negN/A

      \[\leadsto \left(-1 \cdot x\right) \cdot \varepsilon + \frac{-1}{2} \cdot {\varepsilon}^{2} \]
    5. unpow2N/A

      \[\leadsto \left(-1 \cdot x\right) \cdot \varepsilon + \frac{-1}{2} \cdot \left(\varepsilon \cdot \color{blue}{\varepsilon}\right) \]
    6. associate-*r*N/A

      \[\leadsto \left(-1 \cdot x\right) \cdot \varepsilon + \left(\frac{-1}{2} \cdot \varepsilon\right) \cdot \color{blue}{\varepsilon} \]
    7. distribute-rgt-outN/A

      \[\leadsto \varepsilon \cdot \color{blue}{\left(-1 \cdot x + \frac{-1}{2} \cdot \varepsilon\right)} \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \color{blue}{\left(-1 \cdot x + \frac{-1}{2} \cdot \varepsilon\right)}\right) \]
    9. +-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \varepsilon + \color{blue}{-1 \cdot x}\right)\right) \]
    10. mul-1-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \varepsilon + \left(\mathsf{neg}\left(x\right)\right)\right)\right) \]
    11. unsub-negN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \left(\frac{-1}{2} \cdot \varepsilon - \color{blue}{x}\right)\right) \]
    12. --lowering--.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\frac{-1}{2} \cdot \varepsilon\right), \color{blue}{x}\right)\right) \]
    13. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\left(\varepsilon \cdot \frac{-1}{2}\right), x\right)\right) \]
    14. *-lowering-*.f6498.2%

      \[\leadsto \mathsf{*.f64}\left(\varepsilon, \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\varepsilon, \frac{-1}{2}\right), x\right)\right) \]
  8. Simplified98.2%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\varepsilon \cdot -0.5 - x\right)} \]
  9. Add Preprocessing

Alternative 13: 79.0% accurate, 41.0× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(0 - x\right) \end{array} \]
(FPCore (x eps) :precision binary64 (* eps (- 0.0 x)))
double code(double x, double eps) {
	return eps * (0.0 - x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * (0.0d0 - x)
end function
public static double code(double x, double eps) {
	return eps * (0.0 - x);
}
def code(x, eps):
	return eps * (0.0 - x)
function code(x, eps)
	return Float64(eps * Float64(0.0 - x))
end
function tmp = code(x, eps)
	tmp = eps * (0.0 - x);
end
code[x_, eps_] := N[(eps * N[(0.0 - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(0 - x\right)
\end{array}
Derivation
  1. Initial program 52.9%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0

    \[\leadsto \color{blue}{-1 \cdot \left(\varepsilon \cdot \sin x\right)} \]
  4. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \left(-1 \cdot \varepsilon\right) \cdot \color{blue}{\sin x} \]
    2. *-commutativeN/A

      \[\leadsto \sin x \cdot \color{blue}{\left(-1 \cdot \varepsilon\right)} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\sin x, \color{blue}{\left(-1 \cdot \varepsilon\right)}\right) \]
    4. sin-lowering-sin.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{sin.f64}\left(x\right), \left(\color{blue}{-1} \cdot \varepsilon\right)\right) \]
    5. mul-1-negN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{sin.f64}\left(x\right), \left(\mathsf{neg}\left(\varepsilon\right)\right)\right) \]
    6. neg-sub0N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{sin.f64}\left(x\right), \left(0 - \color{blue}{\varepsilon}\right)\right) \]
    7. --lowering--.f6480.3%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{sin.f64}\left(x\right), \mathsf{\_.f64}\left(0, \color{blue}{\varepsilon}\right)\right) \]
  5. Simplified80.3%

    \[\leadsto \color{blue}{\sin x \cdot \left(0 - \varepsilon\right)} \]
  6. Taylor expanded in x around 0

    \[\leadsto \mathsf{*.f64}\left(\color{blue}{\left(x \cdot \left(1 + \frac{-1}{6} \cdot {x}^{2}\right)\right)}, \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
  7. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \left(1 + \frac{-1}{6} \cdot {x}^{2}\right)\right), \mathsf{\_.f64}\left(\color{blue}{0}, \varepsilon\right)\right) \]
    2. +-lowering-+.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\frac{-1}{6} \cdot {x}^{2}\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\frac{-1}{6} \cdot \left(x \cdot x\right)\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    4. associate-*r*N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\left(\frac{-1}{6} \cdot x\right) \cdot x\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    5. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(x \cdot \left(\frac{-1}{6} \cdot x\right)\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \left(\frac{-1}{6} \cdot x\right)\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    7. *-commutativeN/A

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \left(x \cdot \frac{-1}{6}\right)\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
    8. *-lowering-*.f6479.6%

      \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \frac{-1}{6}\right)\right)\right)\right), \mathsf{\_.f64}\left(0, \varepsilon\right)\right) \]
  8. Simplified79.6%

    \[\leadsto \color{blue}{\left(x \cdot \left(1 + x \cdot \left(x \cdot -0.16666666666666666\right)\right)\right)} \cdot \left(0 - \varepsilon\right) \]
  9. Step-by-step derivation
    1. sub0-negN/A

      \[\leadsto \left(x \cdot \left(1 + x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right) \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right) \]
    2. distribute-rgt-neg-outN/A

      \[\leadsto \mathsf{neg}\left(\left(x \cdot \left(1 + x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right) \cdot \varepsilon\right) \]
    3. neg-lowering-neg.f64N/A

      \[\leadsto \mathsf{neg.f64}\left(\left(\left(x \cdot \left(1 + x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right) \cdot \varepsilon\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\left(x \cdot \left(1 + x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right), \varepsilon\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \left(1 + x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right), \varepsilon\right)\right) \]
    6. +-lowering-+.f64N/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(x \cdot \left(x \cdot \frac{-1}{6}\right)\right)\right)\right), \varepsilon\right)\right) \]
    7. associate-*r*N/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \frac{-1}{6}\right)\right)\right), \varepsilon\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \left(\frac{-1}{6} \cdot \left(x \cdot x\right)\right)\right)\right), \varepsilon\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\frac{-1}{6}, \left(x \cdot x\right)\right)\right)\right), \varepsilon\right)\right) \]
    10. *-lowering-*.f6479.6%

      \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\frac{-1}{6}, \mathsf{*.f64}\left(x, x\right)\right)\right)\right), \varepsilon\right)\right) \]
  10. Applied egg-rr79.6%

    \[\leadsto \color{blue}{-\left(x \cdot \left(1 + -0.16666666666666666 \cdot \left(x \cdot x\right)\right)\right) \cdot \varepsilon} \]
  11. Taylor expanded in x around 0

    \[\leadsto \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\color{blue}{x}, \varepsilon\right)\right) \]
  12. Step-by-step derivation
    1. Simplified79.4%

      \[\leadsto -\color{blue}{x} \cdot \varepsilon \]
    2. Final simplification79.4%

      \[\leadsto \varepsilon \cdot \left(0 - x\right) \]
    3. Add Preprocessing

    Alternative 14: 51.2% accurate, 205.0× speedup?

    \[\begin{array}{l} \\ 0 \end{array} \]
    (FPCore (x eps) :precision binary64 0.0)
    double code(double x, double eps) {
    	return 0.0;
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = 0.0d0
    end function
    
    public static double code(double x, double eps) {
    	return 0.0;
    }
    
    def code(x, eps):
    	return 0.0
    
    function code(x, eps)
    	return 0.0
    end
    
    function tmp = code(x, eps)
    	tmp = 0.0;
    end
    
    code[x_, eps_] := 0.0
    
    \begin{array}{l}
    
    \\
    0
    \end{array}
    
    Derivation
    1. Initial program 52.9%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \cos \varepsilon + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)} \]
      2. metadata-evalN/A

        \[\leadsto \cos \varepsilon + -1 \]
      3. +-lowering-+.f64N/A

        \[\leadsto \mathsf{+.f64}\left(\cos \varepsilon, \color{blue}{-1}\right) \]
      4. cos-lowering-cos.f6452.3%

        \[\leadsto \mathsf{+.f64}\left(\mathsf{cos.f64}\left(\varepsilon\right), -1\right) \]
    5. Simplified52.3%

      \[\leadsto \color{blue}{\cos \varepsilon + -1} \]
    6. Taylor expanded in eps around 0

      \[\leadsto \mathsf{+.f64}\left(\color{blue}{1}, -1\right) \]
    7. Step-by-step derivation
      1. Simplified52.2%

        \[\leadsto \color{blue}{1} + -1 \]
      2. Step-by-step derivation
        1. metadata-eval52.2%

          \[\leadsto 0 \]
      3. Applied egg-rr52.2%

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

      Developer Target 1: 99.7% accurate, 1.0× speedup?

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

      Reproduce

      ?
      herbie shell --seed 2024145 
      (FPCore (x eps)
        :name "2cos (problem 3.3.5)"
        :precision binary64
        :pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
      
        :alt
        (! :herbie-platform default (* -2 (sin (+ x (/ eps 2))) (sin (/ eps 2))))
      
        (- (cos (+ x eps)) (cos x)))