2cos (problem 3.3.5)

Percentage Accurate: 52.5% → 99.7%
Time: 15.3s
Alternatives: 9
Speedup: 25.9×

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 9 alternatives:

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

Initial Program: 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: 99.7% accurate, 0.9× speedup?

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

\\
-2 \cdot \left(\sin \left(\varepsilon \cdot 0.5\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right)
\end{array}
Derivation
  1. Initial program 56.2%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
    2. lift-cos.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
    3. lift-cos.f64N/A

      \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
    4. diff-cosN/A

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

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

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
  4. Applied rewrites99.7%

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

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

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

      \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \left(\varepsilon + \color{blue}{\left(\mathsf{neg}\left(-2\right)\right)} \cdot x\right)\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    3. cancel-sign-sub-invN/A

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

      \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right)} \cdot -2 \]
    5. lower-sin.f64N/A

      \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)} \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    6. cancel-sign-sub-invN/A

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

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

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

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

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{x \cdot \left(2 \cdot \frac{1}{2}\right)}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    11. metadata-evalN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + x \cdot \color{blue}{1}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    12. *-rgt-identityN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{x}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    13. lower-fma.f64N/A

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

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

      \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, \frac{1}{2}, x\right)\right) \cdot \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    16. lower-*.f6499.7

      \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right) \cdot \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)}\right) \cdot -2 \]
  7. Applied rewrites99.7%

    \[\leadsto \color{blue}{\left(\sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right) \cdot \sin \left(\varepsilon \cdot 0.5\right)\right)} \cdot -2 \]
  8. Final simplification99.7%

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

Alternative 2: 99.4% accurate, 0.9× speedup?

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

\\
\left(\left(-0.5 \cdot \cos x\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon
\end{array}
Derivation
  1. Initial program 56.2%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  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. *-commutativeN/A

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

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

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

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

      \[\leadsto \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \cdot \varepsilon \]
    6. lower--.f64N/A

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

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

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

      \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
    10. lower-*.f64N/A

      \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
    11. lower-cos.f64N/A

      \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
    12. lower-sin.f6499.4

      \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
  5. Applied rewrites99.4%

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

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

Alternative 3: 99.3% accurate, 1.7× speedup?

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

\\
\left(\left(\varepsilon \cdot 0.5\right) \cdot \sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right)\right) \cdot -2
\end{array}
Derivation
  1. Initial program 56.2%

    \[\cos \left(x + \varepsilon\right) - \cos x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right) - \cos x} \]
    2. lift-cos.f64N/A

      \[\leadsto \color{blue}{\cos \left(x + \varepsilon\right)} - \cos x \]
    3. lift-cos.f64N/A

      \[\leadsto \cos \left(x + \varepsilon\right) - \color{blue}{\cos x} \]
    4. diff-cosN/A

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

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

      \[\leadsto \color{blue}{\left(\sin \left(\frac{\left(x + \varepsilon\right) - x}{2}\right) \cdot \sin \left(\frac{\left(x + \varepsilon\right) + x}{2}\right)\right) \cdot -2} \]
  4. Applied rewrites99.7%

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

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

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

      \[\leadsto \left(\sin \left(\frac{1}{2} \cdot \left(\varepsilon + \color{blue}{\left(\mathsf{neg}\left(-2\right)\right)} \cdot x\right)\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    3. cancel-sign-sub-invN/A

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

      \[\leadsto \color{blue}{\left(\sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right)} \cdot -2 \]
    5. lower-sin.f64N/A

      \[\leadsto \left(\color{blue}{\sin \left(\frac{1}{2} \cdot \left(\varepsilon - -2 \cdot x\right)\right)} \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    6. cancel-sign-sub-invN/A

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

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

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

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

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{x \cdot \left(2 \cdot \frac{1}{2}\right)}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    11. metadata-evalN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + x \cdot \color{blue}{1}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    12. *-rgt-identityN/A

      \[\leadsto \left(\sin \left(\varepsilon \cdot \frac{1}{2} + \color{blue}{x}\right) \cdot \sin \left(\frac{1}{2} \cdot \varepsilon\right)\right) \cdot -2 \]
    13. lower-fma.f64N/A

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

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

      \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, \frac{1}{2}, x\right)\right) \cdot \sin \color{blue}{\left(\varepsilon \cdot \frac{1}{2}\right)}\right) \cdot -2 \]
    16. lower-*.f6499.7

      \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right) \cdot \sin \color{blue}{\left(\varepsilon \cdot 0.5\right)}\right) \cdot -2 \]
  7. Applied rewrites99.7%

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

    \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, \frac{1}{2}, x\right)\right) \cdot \left(\frac{1}{2} \cdot \color{blue}{\varepsilon}\right)\right) \cdot -2 \]
  9. Step-by-step derivation
    1. Applied rewrites99.4%

      \[\leadsto \left(\sin \left(\mathsf{fma}\left(\varepsilon, 0.5, x\right)\right) \cdot \left(0.5 \cdot \color{blue}{\varepsilon}\right)\right) \cdot -2 \]
    2. Final simplification99.4%

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

    Alternative 4: 98.2% accurate, 6.1× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (*
      (fma (fma (fma 0.16666666666666666 x (* 0.25 eps)) x -1.0) x (* -0.5 eps))
      eps))
    double code(double x, double eps) {
    	return fma(fma(fma(0.16666666666666666, x, (0.25 * eps)), x, -1.0), x, (-0.5 * eps)) * eps;
    }
    
    function code(x, eps)
    	return Float64(fma(fma(fma(0.16666666666666666, x, Float64(0.25 * eps)), x, -1.0), x, Float64(-0.5 * eps)) * eps)
    end
    
    code[x_, eps_] := N[(N[(N[(N[(0.16666666666666666 * x + N[(0.25 * eps), $MachinePrecision]), $MachinePrecision] * x + -1.0), $MachinePrecision] * x + N[(-0.5 * eps), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon
    \end{array}
    
    Derivation
    1. Initial program 56.2%

      \[\cos \left(x + \varepsilon\right) - \cos x \]
    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. *-commutativeN/A

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

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

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

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

        \[\leadsto \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \cdot \varepsilon \]
      6. lower--.f64N/A

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

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

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

        \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
      10. lower-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
      11. lower-cos.f64N/A

        \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
      12. lower-sin.f6499.4

        \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
    5. Applied rewrites99.4%

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

      \[\leadsto \left(\frac{-1}{2} \cdot \varepsilon + x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right) \cdot \varepsilon \]
    7. Step-by-step derivation
      1. Applied rewrites98.7%

        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \]
      2. Add Preprocessing

      Alternative 5: 98.2% accurate, 7.4× speedup?

      \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot x, x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (* (fma (fma (* 0.16666666666666666 x) x -1.0) x (* -0.5 eps)) eps))
      double code(double x, double eps) {
      	return fma(fma((0.16666666666666666 * x), x, -1.0), x, (-0.5 * eps)) * eps;
      }
      
      function code(x, eps)
      	return Float64(fma(fma(Float64(0.16666666666666666 * x), x, -1.0), x, Float64(-0.5 * eps)) * eps)
      end
      
      code[x_, eps_] := N[(N[(N[(N[(0.16666666666666666 * x), $MachinePrecision] * x + -1.0), $MachinePrecision] * x + N[(-0.5 * eps), $MachinePrecision]), $MachinePrecision] * eps), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot x, x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon
      \end{array}
      
      Derivation
      1. Initial program 56.2%

        \[\cos \left(x + \varepsilon\right) - \cos x \]
      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. *-commutativeN/A

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

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

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

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

          \[\leadsto \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \cdot \varepsilon \]
        6. lower--.f64N/A

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

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

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

          \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
        10. lower-*.f64N/A

          \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
        11. lower-cos.f64N/A

          \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
        12. lower-sin.f6499.4

          \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
      5. Applied rewrites99.4%

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

        \[\leadsto \left(\frac{-1}{2} \cdot \varepsilon + x \cdot \left(x \cdot \left(\frac{1}{6} \cdot x + \frac{1}{4} \cdot \varepsilon\right) - 1\right)\right) \cdot \varepsilon \]
      7. Step-by-step derivation
        1. Applied rewrites98.7%

          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.25 \cdot \varepsilon\right), x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \]
        2. Taylor expanded in eps around 0

          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot x, x, -1\right), x, \frac{-1}{2} \cdot \varepsilon\right) \cdot \varepsilon \]
        3. Step-by-step derivation
          1. Applied rewrites98.6%

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot x, x, -1\right), x, -0.5 \cdot \varepsilon\right) \cdot \varepsilon \]
          2. Add Preprocessing

          Alternative 6: 98.0% accurate, 10.9× speedup?

          \[\begin{array}{l} \\ \mathsf{fma}\left(-\varepsilon, x, \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right) \end{array} \]
          (FPCore (x eps) :precision binary64 (fma (- eps) x (* (* eps eps) -0.5)))
          double code(double x, double eps) {
          	return fma(-eps, x, ((eps * eps) * -0.5));
          }
          
          function code(x, eps)
          	return fma(Float64(-eps), x, Float64(Float64(eps * eps) * -0.5))
          end
          
          code[x_, eps_] := N[((-eps) * x + N[(N[(eps * eps), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \mathsf{fma}\left(-\varepsilon, x, \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right)
          \end{array}
          
          Derivation
          1. Initial program 56.2%

            \[\cos \left(x + \varepsilon\right) - \cos x \]
          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. *-commutativeN/A

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

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

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

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

              \[\leadsto \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \cdot \varepsilon \]
            6. lower--.f64N/A

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

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

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

              \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
            10. lower-*.f64N/A

              \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
            11. lower-cos.f64N/A

              \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
            12. lower-sin.f6499.4

              \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
          5. Applied rewrites99.4%

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

            \[\leadsto \left(-1 \cdot x + \frac{-1}{2} \cdot \varepsilon\right) \cdot \varepsilon \]
          7. Step-by-step derivation
            1. Applied rewrites98.4%

              \[\leadsto \mathsf{fma}\left(-0.5, \varepsilon, -x\right) \cdot \varepsilon \]
            2. Taylor expanded in x around 0

              \[\leadsto \frac{-1}{2} \cdot {\varepsilon}^{2} + \color{blue}{x \cdot \left(-1 \cdot \varepsilon + \frac{1}{4} \cdot \left({\varepsilon}^{2} \cdot x\right)\right)} \]
            3. Step-by-step derivation
              1. Applied rewrites98.5%

                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\left(x \cdot \varepsilon\right) \cdot \varepsilon, 0.25, -\varepsilon\right), \color{blue}{x}, \left(\varepsilon \cdot \varepsilon\right) \cdot -0.5\right) \]
              2. Taylor expanded in eps around 0

                \[\leadsto \mathsf{fma}\left(-1 \cdot \varepsilon, x, \left(\varepsilon \cdot \varepsilon\right) \cdot \frac{-1}{2}\right) \]
              3. Step-by-step derivation
                1. Applied rewrites98.5%

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

                Alternative 7: 97.8% accurate, 14.8× speedup?

                \[\begin{array}{l} \\ \mathsf{fma}\left(-0.5, \varepsilon, -x\right) \cdot \varepsilon \end{array} \]
                (FPCore (x eps) :precision binary64 (* (fma -0.5 eps (- x)) eps))
                double code(double x, double eps) {
                	return fma(-0.5, eps, -x) * eps;
                }
                
                function code(x, eps)
                	return Float64(fma(-0.5, eps, Float64(-x)) * eps)
                end
                
                code[x_, eps_] := N[(N[(-0.5 * eps + (-x)), $MachinePrecision] * eps), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \mathsf{fma}\left(-0.5, \varepsilon, -x\right) \cdot \varepsilon
                \end{array}
                
                Derivation
                1. Initial program 56.2%

                  \[\cos \left(x + \varepsilon\right) - \cos x \]
                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. *-commutativeN/A

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

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

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

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

                    \[\leadsto \left(\varepsilon \cdot \color{blue}{\left(\frac{-1}{2} \cdot \cos x\right)} - \sin x\right) \cdot \varepsilon \]
                  6. lower--.f64N/A

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

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

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

                    \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
                  10. lower-*.f64N/A

                    \[\leadsto \left(\color{blue}{\left(\cos x \cdot \frac{-1}{2}\right)} \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
                  11. lower-cos.f64N/A

                    \[\leadsto \left(\left(\color{blue}{\cos x} \cdot \frac{-1}{2}\right) \cdot \varepsilon - \sin x\right) \cdot \varepsilon \]
                  12. lower-sin.f6499.4

                    \[\leadsto \left(\left(\cos x \cdot -0.5\right) \cdot \varepsilon - \color{blue}{\sin x}\right) \cdot \varepsilon \]
                5. Applied rewrites99.4%

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

                  \[\leadsto \left(-1 \cdot x + \frac{-1}{2} \cdot \varepsilon\right) \cdot \varepsilon \]
                7. Step-by-step derivation
                  1. Applied rewrites98.4%

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

                  Alternative 8: 78.8% accurate, 25.9× speedup?

                  \[\begin{array}{l} \\ \left(-x\right) \cdot \varepsilon \end{array} \]
                  (FPCore (x eps) :precision binary64 (* (- x) eps))
                  double code(double x, double eps) {
                  	return -x * eps;
                  }
                  
                  real(8) function code(x, eps)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: eps
                      code = -x * eps
                  end function
                  
                  public static double code(double x, double eps) {
                  	return -x * eps;
                  }
                  
                  def code(x, eps):
                  	return -x * eps
                  
                  function code(x, eps)
                  	return Float64(Float64(-x) * eps)
                  end
                  
                  function tmp = code(x, eps)
                  	tmp = -x * eps;
                  end
                  
                  code[x_, eps_] := N[((-x) * eps), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \left(-x\right) \cdot \varepsilon
                  \end{array}
                  
                  Derivation
                  1. Initial program 56.2%

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

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

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

                      \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\varepsilon\right)\right)} \cdot \sin x \]
                    4. lower-neg.f64N/A

                      \[\leadsto \color{blue}{\left(-\varepsilon\right)} \cdot \sin x \]
                    5. lower-sin.f6480.7

                      \[\leadsto \left(-\varepsilon\right) \cdot \color{blue}{\sin x} \]
                  5. Applied rewrites80.7%

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

                    \[\leadsto -1 \cdot \color{blue}{\left(\varepsilon \cdot x\right)} \]
                  7. Step-by-step derivation
                    1. Applied rewrites80.2%

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

                    Alternative 9: 51.3% accurate, 51.8× speedup?

                    \[\begin{array}{l} \\ 1 - 1 \end{array} \]
                    (FPCore (x eps) :precision binary64 (- 1.0 1.0))
                    double code(double x, double eps) {
                    	return 1.0 - 1.0;
                    }
                    
                    real(8) function code(x, eps)
                        real(8), intent (in) :: x
                        real(8), intent (in) :: eps
                        code = 1.0d0 - 1.0d0
                    end function
                    
                    public static double code(double x, double eps) {
                    	return 1.0 - 1.0;
                    }
                    
                    def code(x, eps):
                    	return 1.0 - 1.0
                    
                    function code(x, eps)
                    	return Float64(1.0 - 1.0)
                    end
                    
                    function tmp = code(x, eps)
                    	tmp = 1.0 - 1.0;
                    end
                    
                    code[x_, eps_] := N[(1.0 - 1.0), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    1 - 1
                    \end{array}
                    
                    Derivation
                    1. Initial program 56.2%

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

                      \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
                    4. Step-by-step derivation
                      1. lower--.f64N/A

                        \[\leadsto \color{blue}{\cos \varepsilon - 1} \]
                      2. lower-cos.f6455.4

                        \[\leadsto \color{blue}{\cos \varepsilon} - 1 \]
                    5. Applied rewrites55.4%

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

                      \[\leadsto 1 - 1 \]
                    7. Step-by-step derivation
                      1. Applied rewrites55.3%

                        \[\leadsto 1 - 1 \]
                      2. Add Preprocessing

                      Developer Target 1: 98.8% accurate, 0.5× speedup?

                      \[\begin{array}{l} \\ {\left(\sqrt[3]{\left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)}\right)}^{3} \end{array} \]
                      (FPCore (x eps)
                       :precision binary64
                       (pow (cbrt (* (* -2.0 (sin (* 0.5 (fma 2.0 x eps)))) (sin (* 0.5 eps)))) 3.0))
                      double code(double x, double eps) {
                      	return pow(cbrt(((-2.0 * sin((0.5 * fma(2.0, x, eps)))) * sin((0.5 * eps)))), 3.0);
                      }
                      
                      function code(x, eps)
                      	return cbrt(Float64(Float64(-2.0 * sin(Float64(0.5 * fma(2.0, x, eps)))) * sin(Float64(0.5 * eps)))) ^ 3.0
                      end
                      
                      code[x_, eps_] := N[Power[N[Power[N[(N[(-2.0 * N[Sin[N[(0.5 * N[(2.0 * x + eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(0.5 * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision], 3.0], $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      {\left(\sqrt[3]{\left(-2 \cdot \sin \left(0.5 \cdot \mathsf{fma}\left(2, x, \varepsilon\right)\right)\right) \cdot \sin \left(0.5 \cdot \varepsilon\right)}\right)}^{3}
                      \end{array}
                      

                      Reproduce

                      ?
                      herbie shell --seed 2024248 
                      (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 (pow (cbrt (* -2 (sin (* 1/2 (fma 2 x eps))) (sin (* 1/2 eps)))) 3))
                      
                        (- (cos (+ x eps)) (cos x)))