2tan (problem 3.3.2)

Percentage Accurate: 62.7% → 98.9%
Time: 17.8s
Alternatives: 11
Speedup: 205.0×

Specification

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

\\
\tan \left(x + \varepsilon\right) - \tan 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 11 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: 62.7% accurate, 1.0× speedup?

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

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

Alternative 1: 98.9% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\sin x}{\cos x}\\ t_1 := 1 - \sin x \cdot \frac{\sin \varepsilon}{\cos \varepsilon \cdot \cos x}\\ \frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{t\_1} + \left(\frac{t\_0}{t\_1} - t\_0\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (/ (sin x) (cos x)))
        (t_1 (- 1.0 (* (sin x) (/ (sin eps) (* (cos eps) (cos x)))))))
   (+ (/ (/ (sin eps) (cos eps)) t_1) (- (/ t_0 t_1) t_0))))
double code(double x, double eps) {
	double t_0 = sin(x) / cos(x);
	double t_1 = 1.0 - (sin(x) * (sin(eps) / (cos(eps) * cos(x))));
	return ((sin(eps) / cos(eps)) / t_1) + ((t_0 / t_1) - t_0);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: t_1
    t_0 = sin(x) / cos(x)
    t_1 = 1.0d0 - (sin(x) * (sin(eps) / (cos(eps) * cos(x))))
    code = ((sin(eps) / cos(eps)) / t_1) + ((t_0 / t_1) - t_0)
end function
public static double code(double x, double eps) {
	double t_0 = Math.sin(x) / Math.cos(x);
	double t_1 = 1.0 - (Math.sin(x) * (Math.sin(eps) / (Math.cos(eps) * Math.cos(x))));
	return ((Math.sin(eps) / Math.cos(eps)) / t_1) + ((t_0 / t_1) - t_0);
}
def code(x, eps):
	t_0 = math.sin(x) / math.cos(x)
	t_1 = 1.0 - (math.sin(x) * (math.sin(eps) / (math.cos(eps) * math.cos(x))))
	return ((math.sin(eps) / math.cos(eps)) / t_1) + ((t_0 / t_1) - t_0)
function code(x, eps)
	t_0 = Float64(sin(x) / cos(x))
	t_1 = Float64(1.0 - Float64(sin(x) * Float64(sin(eps) / Float64(cos(eps) * cos(x)))))
	return Float64(Float64(Float64(sin(eps) / cos(eps)) / t_1) + Float64(Float64(t_0 / t_1) - t_0))
end
function tmp = code(x, eps)
	t_0 = sin(x) / cos(x);
	t_1 = 1.0 - (sin(x) * (sin(eps) / (cos(eps) * cos(x))));
	tmp = ((sin(eps) / cos(eps)) / t_1) + ((t_0 / t_1) - t_0);
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Sin[x], $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(1.0 - N[(N[Sin[x], $MachinePrecision] * N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[eps], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[(N[Sin[eps], $MachinePrecision] / N[Cos[eps], $MachinePrecision]), $MachinePrecision] / t$95$1), $MachinePrecision] + N[(N[(t$95$0 / t$95$1), $MachinePrecision] - t$95$0), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\sin x}{\cos x}\\
t_1 := 1 - \sin x \cdot \frac{\sin \varepsilon}{\cos \varepsilon \cdot \cos x}\\
\frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{t\_1} + \left(\frac{t\_0}{t\_1} - t\_0\right)
\end{array}
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. tan-sum60.6%

      \[\leadsto \color{blue}{\frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon}} - \tan x \]
    2. div-inv60.5%

      \[\leadsto \color{blue}{\left(\tan x + \tan \varepsilon\right) \cdot \frac{1}{1 - \tan x \cdot \tan \varepsilon}} - \tan x \]
    3. fmm-def60.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\tan x + \tan \varepsilon, \frac{1}{1 - \tan x \cdot \tan \varepsilon}, -\tan x\right)} \]
  4. Applied egg-rr60.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\tan x + \tan \varepsilon, \frac{1}{1 - \tan x \cdot \tan \varepsilon}, -\tan x\right)} \]
  5. Taylor expanded in x around inf 60.6%

    \[\leadsto \color{blue}{\left(\frac{\sin \varepsilon}{\cos \varepsilon \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} + \frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)}\right) - \frac{\sin x}{\cos x}} \]
  6. Step-by-step derivation
    1. associate--l+99.1%

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} + \left(\frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} - \frac{\sin x}{\cos x}\right)} \]
    2. associate-/r*99.1%

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

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

      \[\leadsto \frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \frac{\sin x \cdot \sin \varepsilon}{\color{blue}{\cos x \cdot \cos \varepsilon}}} + \left(\frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} - \frac{\sin x}{\cos x}\right) \]
    5. associate-/l*99.1%

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

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

    \[\leadsto \frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos \varepsilon \cdot \cos x}} + \left(\frac{\frac{\sin x}{\cos x}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos \varepsilon \cdot \cos x}} - \frac{\sin x}{\cos x}\right) \]
  9. Add Preprocessing

Alternative 2: 98.9% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 - \frac{\sin \varepsilon}{\cos x} \cdot \frac{\sin x}{\cos \varepsilon}\\ \tan x \cdot \left(\frac{1}{t\_0} + -1\right) + \frac{\tan \varepsilon}{t\_0} \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- 1.0 (* (/ (sin eps) (cos x)) (/ (sin x) (cos eps))))))
   (+ (* (tan x) (+ (/ 1.0 t_0) -1.0)) (/ (tan eps) t_0))))
double code(double x, double eps) {
	double t_0 = 1.0 - ((sin(eps) / cos(x)) * (sin(x) / cos(eps)));
	return (tan(x) * ((1.0 / t_0) + -1.0)) + (tan(eps) / t_0);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    t_0 = 1.0d0 - ((sin(eps) / cos(x)) * (sin(x) / cos(eps)))
    code = (tan(x) * ((1.0d0 / t_0) + (-1.0d0))) + (tan(eps) / t_0)
end function
public static double code(double x, double eps) {
	double t_0 = 1.0 - ((Math.sin(eps) / Math.cos(x)) * (Math.sin(x) / Math.cos(eps)));
	return (Math.tan(x) * ((1.0 / t_0) + -1.0)) + (Math.tan(eps) / t_0);
}
def code(x, eps):
	t_0 = 1.0 - ((math.sin(eps) / math.cos(x)) * (math.sin(x) / math.cos(eps)))
	return (math.tan(x) * ((1.0 / t_0) + -1.0)) + (math.tan(eps) / t_0)
function code(x, eps)
	t_0 = Float64(1.0 - Float64(Float64(sin(eps) / cos(x)) * Float64(sin(x) / cos(eps))))
	return Float64(Float64(tan(x) * Float64(Float64(1.0 / t_0) + -1.0)) + Float64(tan(eps) / t_0))
end
function tmp = code(x, eps)
	t_0 = 1.0 - ((sin(eps) / cos(x)) * (sin(x) / cos(eps)));
	tmp = (tan(x) * ((1.0 / t_0) + -1.0)) + (tan(eps) / t_0);
end
code[x_, eps_] := Block[{t$95$0 = N[(1.0 - N[(N[(N[Sin[eps], $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision] * N[(N[Sin[x], $MachinePrecision] / N[Cos[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Tan[x], $MachinePrecision] * N[(N[(1.0 / t$95$0), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision] + N[(N[Tan[eps], $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 - \frac{\sin \varepsilon}{\cos x} \cdot \frac{\sin x}{\cos \varepsilon}\\
\tan x \cdot \left(\frac{1}{t\_0} + -1\right) + \frac{\tan \varepsilon}{t\_0}
\end{array}
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. tan-sum60.6%

      \[\leadsto \color{blue}{\frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon}} - \tan x \]
    2. div-inv60.5%

      \[\leadsto \color{blue}{\left(\tan x + \tan \varepsilon\right) \cdot \frac{1}{1 - \tan x \cdot \tan \varepsilon}} - \tan x \]
    3. fmm-def60.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\tan x + \tan \varepsilon, \frac{1}{1 - \tan x \cdot \tan \varepsilon}, -\tan x\right)} \]
  4. Applied egg-rr60.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\tan x + \tan \varepsilon, \frac{1}{1 - \tan x \cdot \tan \varepsilon}, -\tan x\right)} \]
  5. Taylor expanded in x around inf 60.6%

    \[\leadsto \color{blue}{\left(\frac{\sin \varepsilon}{\cos \varepsilon \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} + \frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)}\right) - \frac{\sin x}{\cos x}} \]
  6. Step-by-step derivation
    1. associate--l+99.1%

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} + \left(\frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} - \frac{\sin x}{\cos x}\right)} \]
    2. associate-/r*99.1%

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

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

      \[\leadsto \frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \frac{\sin x \cdot \sin \varepsilon}{\color{blue}{\cos x \cdot \cos \varepsilon}}} + \left(\frac{\sin x}{\cos x \cdot \left(1 - \frac{\sin \varepsilon \cdot \sin x}{\cos \varepsilon \cdot \cos x}\right)} - \frac{\sin x}{\cos x}\right) \]
    5. associate-/l*99.1%

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

    \[\leadsto \color{blue}{\frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} + \left(\frac{\frac{\sin x}{\cos x}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} - \frac{\sin x}{\cos x}\right)} \]
  8. Step-by-step derivation
    1. tan-quot99.0%

      \[\leadsto \frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} + \left(\frac{\frac{\sin x}{\cos x}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} - \color{blue}{\tan x}\right) \]
    2. associate-+r-60.5%

      \[\leadsto \color{blue}{\left(\frac{\frac{\sin \varepsilon}{\cos \varepsilon}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} + \frac{\frac{\sin x}{\cos x}}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}}\right) - \tan x} \]
  9. Applied egg-rr60.6%

    \[\leadsto \color{blue}{\left(\frac{\tan \varepsilon}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}} + \frac{\tan x}{1 - \sin x \cdot \frac{\sin \varepsilon}{\cos x \cdot \cos \varepsilon}}\right) - \tan x} \]
  10. Step-by-step derivation
    1. associate-+r-99.1%

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

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

    \[\leadsto \color{blue}{\tan x \cdot \left(\frac{1}{1 - \frac{\sin \varepsilon}{\cos x} \cdot \frac{\sin x}{\cos \varepsilon}} + -1\right) + \frac{\tan \varepsilon}{1 - \frac{\sin \varepsilon}{\cos x} \cdot \frac{\sin x}{\cos \varepsilon}}} \]
  12. Add Preprocessing

Alternative 3: 99.4% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\tan x}^{2}\\ \varepsilon \cdot \left(1 + \left(t\_0 + \varepsilon \cdot \left(\sin x \cdot \frac{1 + t\_0}{\cos x}\right)\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (tan x) 2.0)))
   (* eps (+ 1.0 (+ t_0 (* eps (* (sin x) (/ (+ 1.0 t_0) (cos x)))))))))
double code(double x, double eps) {
	double t_0 = pow(tan(x), 2.0);
	return eps * (1.0 + (t_0 + (eps * (sin(x) * ((1.0 + t_0) / cos(x))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    t_0 = tan(x) ** 2.0d0
    code = eps * (1.0d0 + (t_0 + (eps * (sin(x) * ((1.0d0 + t_0) / cos(x))))))
end function
public static double code(double x, double eps) {
	double t_0 = Math.pow(Math.tan(x), 2.0);
	return eps * (1.0 + (t_0 + (eps * (Math.sin(x) * ((1.0 + t_0) / Math.cos(x))))));
}
def code(x, eps):
	t_0 = math.pow(math.tan(x), 2.0)
	return eps * (1.0 + (t_0 + (eps * (math.sin(x) * ((1.0 + t_0) / math.cos(x))))))
function code(x, eps)
	t_0 = tan(x) ^ 2.0
	return Float64(eps * Float64(1.0 + Float64(t_0 + Float64(eps * Float64(sin(x) * Float64(Float64(1.0 + t_0) / cos(x)))))))
end
function tmp = code(x, eps)
	t_0 = tan(x) ^ 2.0;
	tmp = eps * (1.0 + (t_0 + (eps * (sin(x) * ((1.0 + t_0) / cos(x))))));
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(eps * N[(1.0 + N[(t$95$0 + N[(eps * N[(N[Sin[x], $MachinePrecision] * N[(N[(1.0 + t$95$0), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\varepsilon \cdot \left(1 + \left(t\_0 + \varepsilon \cdot \left(\sin x \cdot \frac{1 + t\_0}{\cos x}\right)\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Step-by-step derivation
    1. sub-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \color{blue}{\left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} + \left(-\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)}\right) \]
  7. Applied egg-rr98.6%

    \[\leadsto \varepsilon \cdot \left(1 + \color{blue}{\left(\varepsilon \cdot \left(\sin x \cdot \frac{1 + {\tan x}^{2}}{\cos x}\right) + {\tan x}^{2}\right)}\right) \]
  8. Final simplification98.6%

    \[\leadsto \varepsilon \cdot \left(1 + \left({\tan x}^{2} + \varepsilon \cdot \left(\sin x \cdot \frac{1 + {\tan x}^{2}}{\cos x}\right)\right)\right) \]
  9. Add Preprocessing

Alternative 4: 99.0% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\log \left(e^{\cos x}\right)}^{2}}\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ 1.0 (/ (pow (sin x) 2.0) (pow (log (exp (cos x))) 2.0)))))
double code(double x, double eps) {
	return eps * (1.0 + (pow(sin(x), 2.0) / pow(log(exp(cos(x))), 2.0)));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * (1.0d0 + ((sin(x) ** 2.0d0) / (log(exp(cos(x))) ** 2.0d0)))
end function
public static double code(double x, double eps) {
	return eps * (1.0 + (Math.pow(Math.sin(x), 2.0) / Math.pow(Math.log(Math.exp(Math.cos(x))), 2.0)));
}
def code(x, eps):
	return eps * (1.0 + (math.pow(math.sin(x), 2.0) / math.pow(math.log(math.exp(math.cos(x))), 2.0)))
function code(x, eps)
	return Float64(eps * Float64(1.0 + Float64((sin(x) ^ 2.0) / (log(exp(cos(x))) ^ 2.0))))
end
function tmp = code(x, eps)
	tmp = eps * (1.0 + ((sin(x) ^ 2.0) / (log(exp(cos(x))) ^ 2.0)));
end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Log[N[Exp[N[Cos[x], $MachinePrecision]], $MachinePrecision]], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\log \left(e^{\cos x}\right)}^{2}}\right)
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 98.3%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  7. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  8. Simplified98.3%

    \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  9. Step-by-step derivation
    1. add-log-exp98.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{{\color{blue}{\log \left(e^{\cos x}\right)}}^{2}}\right) \cdot \varepsilon \]
  10. Applied egg-rr98.3%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{{\color{blue}{\log \left(e^{\cos x}\right)}}^{2}}\right) \cdot \varepsilon \]
  11. Final simplification98.3%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\log \left(e^{\cos x}\right)}^{2}}\right) \]
  12. Add Preprocessing

Alternative 5: 99.0% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot e^{\mathsf{log1p}\left({\sin x}^{2} \cdot {\cos x}^{-2}\right)} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (exp (log1p (* (pow (sin x) 2.0) (pow (cos x) -2.0))))))
double code(double x, double eps) {
	return eps * exp(log1p((pow(sin(x), 2.0) * pow(cos(x), -2.0))));
}
public static double code(double x, double eps) {
	return eps * Math.exp(Math.log1p((Math.pow(Math.sin(x), 2.0) * Math.pow(Math.cos(x), -2.0))));
}
def code(x, eps):
	return eps * math.exp(math.log1p((math.pow(math.sin(x), 2.0) * math.pow(math.cos(x), -2.0))))
function code(x, eps)
	return Float64(eps * exp(log1p(Float64((sin(x) ^ 2.0) * (cos(x) ^ -2.0)))))
end
code[x_, eps_] := N[(eps * N[Exp[N[Log[1 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] * N[Power[N[Cos[x], $MachinePrecision], -2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot e^{\mathsf{log1p}\left({\sin x}^{2} \cdot {\cos x}^{-2}\right)}
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 98.3%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  7. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  8. Simplified98.3%

    \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  9. Step-by-step derivation
    1. add-exp-log98.3%

      \[\leadsto \color{blue}{e^{\log \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}} \cdot \varepsilon \]
    2. log1p-define98.3%

      \[\leadsto e^{\color{blue}{\mathsf{log1p}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}} \cdot \varepsilon \]
    3. pow198.3%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}^{1}}\right)} \cdot \varepsilon \]
    4. div-inv98.3%

      \[\leadsto e^{\mathsf{log1p}\left({\color{blue}{\left({\sin x}^{2} \cdot \frac{1}{{\cos x}^{2}}\right)}}^{1}\right)} \cdot \varepsilon \]
    5. pow198.3%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{{\sin x}^{2} \cdot \frac{1}{{\cos x}^{2}}}\right)} \cdot \varepsilon \]
    6. pow-flip98.3%

      \[\leadsto e^{\mathsf{log1p}\left({\sin x}^{2} \cdot \color{blue}{{\cos x}^{\left(-2\right)}}\right)} \cdot \varepsilon \]
    7. metadata-eval98.3%

      \[\leadsto e^{\mathsf{log1p}\left({\sin x}^{2} \cdot {\cos x}^{\color{blue}{-2}}\right)} \cdot \varepsilon \]
  10. Applied egg-rr98.3%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left({\sin x}^{2} \cdot {\cos x}^{-2}\right)}} \cdot \varepsilon \]
  11. Final simplification98.3%

    \[\leadsto \varepsilon \cdot e^{\mathsf{log1p}\left({\sin x}^{2} \cdot {\cos x}^{-2}\right)} \]
  12. Add Preprocessing

Alternative 6: 99.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\frac{1 + \cos \left(x \cdot 2\right)}{2}}\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ 1.0 (/ (pow (sin x) 2.0) (/ (+ 1.0 (cos (* x 2.0))) 2.0)))))
double code(double x, double eps) {
	return eps * (1.0 + (pow(sin(x), 2.0) / ((1.0 + cos((x * 2.0))) / 2.0)));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * (1.0d0 + ((sin(x) ** 2.0d0) / ((1.0d0 + cos((x * 2.0d0))) / 2.0d0)))
end function
public static double code(double x, double eps) {
	return eps * (1.0 + (Math.pow(Math.sin(x), 2.0) / ((1.0 + Math.cos((x * 2.0))) / 2.0)));
}
def code(x, eps):
	return eps * (1.0 + (math.pow(math.sin(x), 2.0) / ((1.0 + math.cos((x * 2.0))) / 2.0)))
function code(x, eps)
	return Float64(eps * Float64(1.0 + Float64((sin(x) ^ 2.0) / Float64(Float64(1.0 + cos(Float64(x * 2.0))) / 2.0))))
end
function tmp = code(x, eps)
	tmp = eps * (1.0 + ((sin(x) ^ 2.0) / ((1.0 + cos((x * 2.0))) / 2.0)));
end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[(N[(1.0 + N[Cos[N[(x * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\frac{1 + \cos \left(x \cdot 2\right)}{2}}\right)
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 98.3%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  7. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  8. Simplified98.3%

    \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  9. Step-by-step derivation
    1. unpow298.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\cos x \cdot \cos x}}\right) \cdot \varepsilon \]
    2. cos-mult98.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{\cos \left(x + x\right) + \cos \left(x - x\right)}{2}}}\right) \cdot \varepsilon \]
  10. Applied egg-rr98.3%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{\cos \left(x + x\right) + \cos \left(x - x\right)}{2}}}\right) \cdot \varepsilon \]
  11. Step-by-step derivation
    1. +-commutative98.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\frac{\color{blue}{\cos \left(x - x\right) + \cos \left(x + x\right)}}{2}}\right) \cdot \varepsilon \]
    2. +-inverses98.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\frac{\cos \color{blue}{0} + \cos \left(x + x\right)}{2}}\right) \cdot \varepsilon \]
    3. cos-098.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\frac{\color{blue}{1} + \cos \left(x + x\right)}{2}}\right) \cdot \varepsilon \]
    4. count-298.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\frac{1 + \cos \color{blue}{\left(2 \cdot x\right)}}{2}}\right) \cdot \varepsilon \]
    5. *-commutative98.3%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\frac{1 + \cos \color{blue}{\left(x \cdot 2\right)}}{2}}\right) \cdot \varepsilon \]
  12. Simplified98.3%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1 + \cos \left(x \cdot 2\right)}{2}}}\right) \cdot \varepsilon \]
  13. Final simplification98.3%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\frac{1 + \cos \left(x \cdot 2\right)}{2}}\right) \]
  14. Add Preprocessing

Alternative 7: 98.4% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(-1 + \left(2 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ -1.0 (+ 2.0 (/ (pow (sin x) 2.0) (- 1.0 (pow x 2.0)))))))
double code(double x, double eps) {
	return eps * (-1.0 + (2.0 + (pow(sin(x), 2.0) / (1.0 - pow(x, 2.0)))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * ((-1.0d0) + (2.0d0 + ((sin(x) ** 2.0d0) / (1.0d0 - (x ** 2.0d0)))))
end function
public static double code(double x, double eps) {
	return eps * (-1.0 + (2.0 + (Math.pow(Math.sin(x), 2.0) / (1.0 - Math.pow(x, 2.0)))));
}
def code(x, eps):
	return eps * (-1.0 + (2.0 + (math.pow(math.sin(x), 2.0) / (1.0 - math.pow(x, 2.0)))))
function code(x, eps)
	return Float64(eps * Float64(-1.0 + Float64(2.0 + Float64((sin(x) ^ 2.0) / Float64(1.0 - (x ^ 2.0))))))
end
function tmp = code(x, eps)
	tmp = eps * (-1.0 + (2.0 + ((sin(x) ^ 2.0) / (1.0 - (x ^ 2.0)))));
end
code[x_, eps_] := N[(eps * N[(-1.0 + N[(2.0 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[(1.0 - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(-1 + \left(2 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right)
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 98.3%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  7. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  8. Simplified98.3%

    \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  9. Taylor expanded in x around 0 97.4%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 + -1 \cdot {x}^{2}}}\right) \cdot \varepsilon \]
  10. Step-by-step derivation
    1. mul-1-neg97.4%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{1 + \color{blue}{\left(-{x}^{2}\right)}}\right) \cdot \varepsilon \]
    2. unsub-neg97.4%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 - {x}^{2}}}\right) \cdot \varepsilon \]
  11. Simplified97.4%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 - {x}^{2}}}\right) \cdot \varepsilon \]
  12. Step-by-step derivation
    1. expm1-log1p-u97.4%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right)} \cdot \varepsilon \]
    2. expm1-undefine97.4%

      \[\leadsto \color{blue}{\left(e^{\mathsf{log1p}\left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)} - 1\right)} \cdot \varepsilon \]
  13. Applied egg-rr97.4%

    \[\leadsto \color{blue}{\left(e^{\mathsf{log1p}\left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)} - 1\right)} \cdot \varepsilon \]
  14. Step-by-step derivation
    1. sub-neg97.4%

      \[\leadsto \color{blue}{\left(e^{\mathsf{log1p}\left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)} + \left(-1\right)\right)} \cdot \varepsilon \]
    2. log1p-undefine97.4%

      \[\leadsto \left(e^{\color{blue}{\log \left(1 + \left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right)}} + \left(-1\right)\right) \cdot \varepsilon \]
    3. rem-exp-log97.4%

      \[\leadsto \left(\color{blue}{\left(1 + \left(1 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right)} + \left(-1\right)\right) \cdot \varepsilon \]
    4. associate-+r+97.4%

      \[\leadsto \left(\color{blue}{\left(\left(1 + 1\right) + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)} + \left(-1\right)\right) \cdot \varepsilon \]
    5. metadata-eval97.4%

      \[\leadsto \left(\left(\color{blue}{2} + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right) + \left(-1\right)\right) \cdot \varepsilon \]
    6. metadata-eval97.4%

      \[\leadsto \left(\left(2 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right) + \color{blue}{-1}\right) \cdot \varepsilon \]
  15. Simplified97.4%

    \[\leadsto \color{blue}{\left(\left(2 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right) + -1\right)} \cdot \varepsilon \]
  16. Final simplification97.4%

    \[\leadsto \varepsilon \cdot \left(-1 + \left(2 + \frac{{\sin x}^{2}}{1 - {x}^{2}}\right)\right) \]
  17. Add Preprocessing

Alternative 8: 98.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{1 - x \cdot x}\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (* eps (+ 1.0 (/ (pow (sin x) 2.0) (- 1.0 (* x x))))))
double code(double x, double eps) {
	return eps * (1.0 + (pow(sin(x), 2.0) / (1.0 - (x * x))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * (1.0d0 + ((sin(x) ** 2.0d0) / (1.0d0 - (x * x))))
end function
public static double code(double x, double eps) {
	return eps * (1.0 + (Math.pow(Math.sin(x), 2.0) / (1.0 - (x * x))));
}
def code(x, eps):
	return eps * (1.0 + (math.pow(math.sin(x), 2.0) / (1.0 - (x * x))))
function code(x, eps)
	return Float64(eps * Float64(1.0 + Float64((sin(x) ^ 2.0) / Float64(1.0 - Float64(x * x)))))
end
function tmp = code(x, eps)
	tmp = eps * (1.0 + ((sin(x) ^ 2.0) / (1.0 - (x * x))));
end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{1 - x \cdot x}\right)
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in eps around 0 98.3%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  7. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  8. Simplified98.3%

    \[\leadsto \color{blue}{\left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) \cdot \varepsilon} \]
  9. Taylor expanded in x around 0 97.4%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 + -1 \cdot {x}^{2}}}\right) \cdot \varepsilon \]
  10. Step-by-step derivation
    1. mul-1-neg97.4%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{1 + \color{blue}{\left(-{x}^{2}\right)}}\right) \cdot \varepsilon \]
    2. unsub-neg97.4%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 - {x}^{2}}}\right) \cdot \varepsilon \]
  11. Simplified97.4%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{\color{blue}{1 - {x}^{2}}}\right) \cdot \varepsilon \]
  12. Step-by-step derivation
    1. unpow297.4%

      \[\leadsto \left(1 + \frac{{\sin x}^{2}}{1 - \color{blue}{x \cdot x}}\right) \cdot \varepsilon \]
  13. Applied egg-rr97.4%

    \[\leadsto \left(1 + \frac{{\sin x}^{2}}{1 - \color{blue}{x \cdot x}}\right) \cdot \varepsilon \]
  14. Final simplification97.4%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{1 - x \cdot x}\right) \]
  15. Add Preprocessing

Alternative 9: 97.9% accurate, 2.0× speedup?

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

\\
\tan \varepsilon
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 97.4%

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
  4. Step-by-step derivation
    1. tan-quot97.4%

      \[\leadsto \color{blue}{\tan \varepsilon} \]
    2. *-un-lft-identity97.4%

      \[\leadsto \color{blue}{1 \cdot \tan \varepsilon} \]
  5. Applied egg-rr97.4%

    \[\leadsto \color{blue}{1 \cdot \tan \varepsilon} \]
  6. Step-by-step derivation
    1. *-lft-identity97.4%

      \[\leadsto \color{blue}{\tan \varepsilon} \]
  7. Simplified97.4%

    \[\leadsto \color{blue}{\tan \varepsilon} \]
  8. Add Preprocessing

Alternative 10: 98.3% accurate, 22.8× speedup?

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

\\
\varepsilon \cdot \left(1 + x \cdot \left(\varepsilon + x\right)\right)
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in x around 0 97.3%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + x \cdot \left(\varepsilon + x\right)\right)} \]
  7. Step-by-step derivation
    1. +-commutative97.3%

      \[\leadsto \varepsilon \cdot \left(1 + x \cdot \color{blue}{\left(x + \varepsilon\right)}\right) \]
  8. Simplified97.3%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + x \cdot \left(x + \varepsilon\right)\right)} \]
  9. Final simplification97.3%

    \[\leadsto \varepsilon \cdot \left(1 + x \cdot \left(\varepsilon + x\right)\right) \]
  10. Add Preprocessing

Alternative 11: 97.9% accurate, 205.0× speedup?

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

\\
\varepsilon
\end{array}
Derivation
  1. Initial program 60.3%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Step-by-step derivation
    1. associate--l+98.6%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
    2. associate-/l*98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\varepsilon \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    3. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)}{\cos x} - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \]
    4. mul-1-neg98.6%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
  5. Simplified98.6%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  6. Taylor expanded in x around 0 97.3%

    \[\leadsto \color{blue}{\varepsilon} \]
  7. Add Preprocessing

Developer Target 1: 99.9% accurate, 0.7× speedup?

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

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

Developer Target 2: 62.9% accurate, 0.4× speedup?

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

\\
\frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon} - \tan x
\end{array}

Developer Target 3: 99.0% accurate, 1.0× speedup?

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

\\
\varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x
\end{array}

Reproduce

?
herbie shell --seed 2024169 
(FPCore (x eps)
  :name "2tan (problem 3.3.2)"
  :precision binary64
  :pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))

  :alt
  (! :herbie-platform default (/ (sin eps) (* (cos x) (cos (+ x eps)))))

  :alt
  (! :herbie-platform default (- (/ (+ (tan x) (tan eps)) (- 1 (* (tan x) (tan eps)))) (tan x)))

  :alt
  (! :herbie-platform default (+ eps (* eps (tan x) (tan x))))

  (- (tan (+ x eps)) (tan x)))