2tan (problem 3.3.2)

Percentage Accurate: 62.0% → 99.6%
Time: 18.6s
Alternatives: 14
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 14 alternatives:

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

Initial Program: 62.0% 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: 99.6% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\cos x}^{2}\\ t_1 := {\sin x}^{2}\\ t_2 := \frac{t\_1}{t\_0}\\ t_3 := 1 + t\_2\\ \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(\frac{\sin x \cdot t\_3}{\cos x} - \varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, t\_1 \cdot \frac{t\_3}{t\_0}, \mathsf{fma}\left(-0.5, t\_3, 0.16666666666666666 \cdot t\_2\right)\right)\right)\right) + \frac{1}{\frac{t\_0}{t\_1}}\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (cos x) 2.0))
        (t_1 (pow (sin x) 2.0))
        (t_2 (/ t_1 t_0))
        (t_3 (+ 1.0 t_2)))
   (*
    eps
    (+
     1.0
     (+
      (*
       eps
       (-
        (/ (* (sin x) t_3) (cos x))
        (*
         eps
         (+
          0.16666666666666666
          (fma
           -1.0
           (* t_1 (/ t_3 t_0))
           (fma -0.5 t_3 (* 0.16666666666666666 t_2)))))))
      (/ 1.0 (/ t_0 t_1)))))))
double code(double x, double eps) {
	double t_0 = pow(cos(x), 2.0);
	double t_1 = pow(sin(x), 2.0);
	double t_2 = t_1 / t_0;
	double t_3 = 1.0 + t_2;
	return eps * (1.0 + ((eps * (((sin(x) * t_3) / cos(x)) - (eps * (0.16666666666666666 + fma(-1.0, (t_1 * (t_3 / t_0)), fma(-0.5, t_3, (0.16666666666666666 * t_2))))))) + (1.0 / (t_0 / t_1))));
}
function code(x, eps)
	t_0 = cos(x) ^ 2.0
	t_1 = sin(x) ^ 2.0
	t_2 = Float64(t_1 / t_0)
	t_3 = Float64(1.0 + t_2)
	return Float64(eps * Float64(1.0 + Float64(Float64(eps * Float64(Float64(Float64(sin(x) * t_3) / cos(x)) - Float64(eps * Float64(0.16666666666666666 + fma(-1.0, Float64(t_1 * Float64(t_3 / t_0)), fma(-0.5, t_3, Float64(0.16666666666666666 * t_2))))))) + Float64(1.0 / Float64(t_0 / t_1)))))
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 / t$95$0), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 + t$95$2), $MachinePrecision]}, N[(eps * N[(1.0 + N[(N[(eps * N[(N[(N[(N[Sin[x], $MachinePrecision] * t$95$3), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision] - N[(eps * N[(0.16666666666666666 + N[(-1.0 * N[(t$95$1 * N[(t$95$3 / t$95$0), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * t$95$3 + N[(0.16666666666666666 * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(t$95$0 / t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\cos x}^{2}\\
t_1 := {\sin x}^{2}\\
t_2 := \frac{t\_1}{t\_0}\\
t_3 := 1 + t\_2\\
\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(\frac{\sin x \cdot t\_3}{\cos x} - \varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, t\_1 \cdot \frac{t\_3}{t\_0}, \mathsf{fma}\left(-0.5, t\_3, 0.16666666666666666 \cdot t\_2\right)\right)\right)\right) + \frac{1}{\frac{t\_0}{t\_1}}\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Step-by-step derivation
    1. clear-num99.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
    2. inv-pow99.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{{\left(\frac{{\cos x}^{2}}{{\sin x}^{2}}\right)}^{-1}}\right)\right)\right) \]
  6. Applied egg-rr99.1%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{{\left(\frac{{\cos x}^{2}}{{\sin x}^{2}}\right)}^{-1}}\right)\right)\right) \]
  7. Step-by-step derivation
    1. unpow-199.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
  8. Simplified99.1%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
  9. Final simplification99.1%

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

Alternative 2: 99.6% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\sin x}^{2}\\ t_1 := {\cos x}^{2}\\ t_2 := \frac{t\_0}{t\_1}\\ t_3 := 1 + t\_2\\ \varepsilon \cdot \left(1 + \left(t\_2 + \varepsilon \cdot \left(\frac{\sin x \cdot t\_3}{\cos x} - \varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, t\_0 \cdot \frac{t\_3}{t\_1}, \mathsf{fma}\left(-0.5, t\_3, 0.16666666666666666 \cdot t\_2\right)\right)\right)\right)\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (sin x) 2.0))
        (t_1 (pow (cos x) 2.0))
        (t_2 (/ t_0 t_1))
        (t_3 (+ 1.0 t_2)))
   (*
    eps
    (+
     1.0
     (+
      t_2
      (*
       eps
       (-
        (/ (* (sin x) t_3) (cos x))
        (*
         eps
         (+
          0.16666666666666666
          (fma
           -1.0
           (* t_0 (/ t_3 t_1))
           (fma -0.5 t_3 (* 0.16666666666666666 t_2))))))))))))
double code(double x, double eps) {
	double t_0 = pow(sin(x), 2.0);
	double t_1 = pow(cos(x), 2.0);
	double t_2 = t_0 / t_1;
	double t_3 = 1.0 + t_2;
	return eps * (1.0 + (t_2 + (eps * (((sin(x) * t_3) / cos(x)) - (eps * (0.16666666666666666 + fma(-1.0, (t_0 * (t_3 / t_1)), fma(-0.5, t_3, (0.16666666666666666 * t_2)))))))));
}
function code(x, eps)
	t_0 = sin(x) ^ 2.0
	t_1 = cos(x) ^ 2.0
	t_2 = Float64(t_0 / t_1)
	t_3 = Float64(1.0 + t_2)
	return Float64(eps * Float64(1.0 + Float64(t_2 + Float64(eps * Float64(Float64(Float64(sin(x) * t_3) / cos(x)) - Float64(eps * Float64(0.16666666666666666 + fma(-1.0, Float64(t_0 * Float64(t_3 / t_1)), fma(-0.5, t_3, Float64(0.16666666666666666 * t_2))))))))))
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$2 = N[(t$95$0 / t$95$1), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 + t$95$2), $MachinePrecision]}, N[(eps * N[(1.0 + N[(t$95$2 + N[(eps * N[(N[(N[(N[Sin[x], $MachinePrecision] * t$95$3), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision] - N[(eps * N[(0.16666666666666666 + N[(-1.0 * N[(t$95$0 * N[(t$95$3 / t$95$1), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * t$95$3 + N[(0.16666666666666666 * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\sin x}^{2}\\
t_1 := {\cos x}^{2}\\
t_2 := \frac{t\_0}{t\_1}\\
t_3 := 1 + t\_2\\
\varepsilon \cdot \left(1 + \left(t\_2 + \varepsilon \cdot \left(\frac{\sin x \cdot t\_3}{\cos x} - \varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, t\_0 \cdot \frac{t\_3}{t\_1}, \mathsf{fma}\left(-0.5, t\_3, 0.16666666666666666 \cdot t\_2\right)\right)\right)\right)\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Final simplification99.1%

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

Alternative 3: 99.6% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\sin x}^{2}\\ t_1 := {\cos x}^{2}\\ t_2 := \frac{t\_0}{t\_1}\\ t_3 := 1 + t\_2\\ \varepsilon \cdot \left(t\_2 + \left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(\left(\frac{t\_0 \cdot t\_3}{t\_1} + \left(-0.5 \cdot \left(-1 - t\_2\right) - 0.16666666666666666 \cdot t\_2\right)\right) - 0.16666666666666666\right) + \frac{\sin x \cdot t\_3}{\cos x}\right)\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (sin x) 2.0))
        (t_1 (pow (cos x) 2.0))
        (t_2 (/ t_0 t_1))
        (t_3 (+ 1.0 t_2)))
   (*
    eps
    (+
     t_2
     (+
      1.0
      (*
       eps
       (+
        (*
         eps
         (-
          (+
           (/ (* t_0 t_3) t_1)
           (- (* -0.5 (- -1.0 t_2)) (* 0.16666666666666666 t_2)))
          0.16666666666666666))
        (/ (* (sin x) t_3) (cos x)))))))))
double code(double x, double eps) {
	double t_0 = pow(sin(x), 2.0);
	double t_1 = pow(cos(x), 2.0);
	double t_2 = t_0 / t_1;
	double t_3 = 1.0 + t_2;
	return eps * (t_2 + (1.0 + (eps * ((eps * ((((t_0 * t_3) / t_1) + ((-0.5 * (-1.0 - t_2)) - (0.16666666666666666 * t_2))) - 0.16666666666666666)) + ((sin(x) * t_3) / cos(x))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: t_3
    t_0 = sin(x) ** 2.0d0
    t_1 = cos(x) ** 2.0d0
    t_2 = t_0 / t_1
    t_3 = 1.0d0 + t_2
    code = eps * (t_2 + (1.0d0 + (eps * ((eps * ((((t_0 * t_3) / t_1) + (((-0.5d0) * ((-1.0d0) - t_2)) - (0.16666666666666666d0 * t_2))) - 0.16666666666666666d0)) + ((sin(x) * t_3) / cos(x))))))
end function
public static double code(double x, double eps) {
	double t_0 = Math.pow(Math.sin(x), 2.0);
	double t_1 = Math.pow(Math.cos(x), 2.0);
	double t_2 = t_0 / t_1;
	double t_3 = 1.0 + t_2;
	return eps * (t_2 + (1.0 + (eps * ((eps * ((((t_0 * t_3) / t_1) + ((-0.5 * (-1.0 - t_2)) - (0.16666666666666666 * t_2))) - 0.16666666666666666)) + ((Math.sin(x) * t_3) / Math.cos(x))))));
}
def code(x, eps):
	t_0 = math.pow(math.sin(x), 2.0)
	t_1 = math.pow(math.cos(x), 2.0)
	t_2 = t_0 / t_1
	t_3 = 1.0 + t_2
	return eps * (t_2 + (1.0 + (eps * ((eps * ((((t_0 * t_3) / t_1) + ((-0.5 * (-1.0 - t_2)) - (0.16666666666666666 * t_2))) - 0.16666666666666666)) + ((math.sin(x) * t_3) / math.cos(x))))))
function code(x, eps)
	t_0 = sin(x) ^ 2.0
	t_1 = cos(x) ^ 2.0
	t_2 = Float64(t_0 / t_1)
	t_3 = Float64(1.0 + t_2)
	return Float64(eps * Float64(t_2 + Float64(1.0 + Float64(eps * Float64(Float64(eps * Float64(Float64(Float64(Float64(t_0 * t_3) / t_1) + Float64(Float64(-0.5 * Float64(-1.0 - t_2)) - Float64(0.16666666666666666 * t_2))) - 0.16666666666666666)) + Float64(Float64(sin(x) * t_3) / cos(x)))))))
end
function tmp = code(x, eps)
	t_0 = sin(x) ^ 2.0;
	t_1 = cos(x) ^ 2.0;
	t_2 = t_0 / t_1;
	t_3 = 1.0 + t_2;
	tmp = eps * (t_2 + (1.0 + (eps * ((eps * ((((t_0 * t_3) / t_1) + ((-0.5 * (-1.0 - t_2)) - (0.16666666666666666 * t_2))) - 0.16666666666666666)) + ((sin(x) * t_3) / cos(x))))));
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$2 = N[(t$95$0 / t$95$1), $MachinePrecision]}, Block[{t$95$3 = N[(1.0 + t$95$2), $MachinePrecision]}, N[(eps * N[(t$95$2 + N[(1.0 + N[(eps * N[(N[(eps * N[(N[(N[(N[(t$95$0 * t$95$3), $MachinePrecision] / t$95$1), $MachinePrecision] + N[(N[(-0.5 * N[(-1.0 - t$95$2), $MachinePrecision]), $MachinePrecision] - N[(0.16666666666666666 * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 0.16666666666666666), $MachinePrecision]), $MachinePrecision] + N[(N[(N[Sin[x], $MachinePrecision] * t$95$3), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\sin x}^{2}\\
t_1 := {\cos x}^{2}\\
t_2 := \frac{t\_0}{t\_1}\\
t_3 := 1 + t\_2\\
\varepsilon \cdot \left(t\_2 + \left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(\left(\frac{t\_0 \cdot t\_3}{t\_1} + \left(-0.5 \cdot \left(-1 - t\_2\right) - 0.16666666666666666 \cdot t\_2\right)\right) - 0.16666666666666666\right) + \frac{\sin x \cdot t\_3}{\cos x}\right)\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Final simplification99.1%

    \[\leadsto \varepsilon \cdot \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \left(1 + \varepsilon \cdot \left(\varepsilon \cdot \left(\left(\frac{{\sin x}^{2} \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(-1 - \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) - 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) - 0.16666666666666666\right) + \frac{\sin x \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right)\right) \]
  5. Add Preprocessing

Alternative 4: 99.4% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{{\sin x}^{2}}{{\cos x}^{2}}\\ \varepsilon \cdot \left(1 + \left(t\_0 + \varepsilon \cdot \left(\frac{\sin x \cdot \left(1 + t\_0\right)}{\cos x} + \varepsilon \cdot \left(0.3333333333333333 - -1.3333333333333333 \cdot {x}^{2}\right)\right)\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (/ (pow (sin x) 2.0) (pow (cos x) 2.0))))
   (*
    eps
    (+
     1.0
     (+
      t_0
      (*
       eps
       (+
        (/ (* (sin x) (+ 1.0 t_0)) (cos x))
        (*
         eps
         (- 0.3333333333333333 (* -1.3333333333333333 (pow x 2.0)))))))))))
double code(double x, double eps) {
	double t_0 = pow(sin(x), 2.0) / pow(cos(x), 2.0);
	return eps * (1.0 + (t_0 + (eps * (((sin(x) * (1.0 + t_0)) / cos(x)) + (eps * (0.3333333333333333 - (-1.3333333333333333 * pow(x, 2.0))))))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    t_0 = (sin(x) ** 2.0d0) / (cos(x) ** 2.0d0)
    code = eps * (1.0d0 + (t_0 + (eps * (((sin(x) * (1.0d0 + t_0)) / cos(x)) + (eps * (0.3333333333333333d0 - ((-1.3333333333333333d0) * (x ** 2.0d0))))))))
end function
public static double code(double x, double eps) {
	double t_0 = Math.pow(Math.sin(x), 2.0) / Math.pow(Math.cos(x), 2.0);
	return eps * (1.0 + (t_0 + (eps * (((Math.sin(x) * (1.0 + t_0)) / Math.cos(x)) + (eps * (0.3333333333333333 - (-1.3333333333333333 * Math.pow(x, 2.0))))))));
}
def code(x, eps):
	t_0 = math.pow(math.sin(x), 2.0) / math.pow(math.cos(x), 2.0)
	return eps * (1.0 + (t_0 + (eps * (((math.sin(x) * (1.0 + t_0)) / math.cos(x)) + (eps * (0.3333333333333333 - (-1.3333333333333333 * math.pow(x, 2.0))))))))
function code(x, eps)
	t_0 = Float64((sin(x) ^ 2.0) / (cos(x) ^ 2.0))
	return Float64(eps * Float64(1.0 + Float64(t_0 + Float64(eps * Float64(Float64(Float64(sin(x) * Float64(1.0 + t_0)) / cos(x)) + Float64(eps * Float64(0.3333333333333333 - Float64(-1.3333333333333333 * (x ^ 2.0)))))))))
end
function tmp = code(x, eps)
	t_0 = (sin(x) ^ 2.0) / (cos(x) ^ 2.0);
	tmp = eps * (1.0 + (t_0 + (eps * (((sin(x) * (1.0 + t_0)) / cos(x)) + (eps * (0.3333333333333333 - (-1.3333333333333333 * (x ^ 2.0))))))));
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]}, N[(eps * N[(1.0 + N[(t$95$0 + N[(eps * N[(N[(N[(N[Sin[x], $MachinePrecision] * N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision] + N[(eps * N[(0.3333333333333333 - N[(-1.3333333333333333 * N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{{\sin x}^{2}}{{\cos x}^{2}}\\
\varepsilon \cdot \left(1 + \left(t\_0 + \varepsilon \cdot \left(\frac{\sin x \cdot \left(1 + t\_0\right)}{\cos x} + \varepsilon \cdot \left(0.3333333333333333 - -1.3333333333333333 \cdot {x}^{2}\right)\right)\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Taylor expanded in x around 0 98.9%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \color{blue}{\left(-1.3333333333333333 \cdot {x}^{2} - 0.3333333333333333\right)} - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) \]
  6. Final simplification98.9%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \varepsilon \cdot \left(\frac{\sin x \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x} + \varepsilon \cdot \left(0.3333333333333333 - -1.3333333333333333 \cdot {x}^{2}\right)\right)\right)\right) \]
  7. Add Preprocessing

Alternative 5: 99.4% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\cos x}^{2}\\ t_1 := {\sin x}^{2}\\ \varepsilon \cdot \left(1 + \left(\frac{1}{\frac{t\_0}{t\_1}} - \frac{\varepsilon \cdot \left(\sin x \cdot \left(-1 - \frac{t\_1}{t\_0}\right)\right)}{\cos x}\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (pow (cos x) 2.0)) (t_1 (pow (sin x) 2.0)))
   (*
    eps
    (+
     1.0
     (-
      (/ 1.0 (/ t_0 t_1))
      (/ (* eps (* (sin x) (- -1.0 (/ t_1 t_0)))) (cos x)))))))
double code(double x, double eps) {
	double t_0 = pow(cos(x), 2.0);
	double t_1 = pow(sin(x), 2.0);
	return eps * (1.0 + ((1.0 / (t_0 / t_1)) - ((eps * (sin(x) * (-1.0 - (t_1 / t_0)))) / cos(x))));
}
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 = cos(x) ** 2.0d0
    t_1 = sin(x) ** 2.0d0
    code = eps * (1.0d0 + ((1.0d0 / (t_0 / t_1)) - ((eps * (sin(x) * ((-1.0d0) - (t_1 / t_0)))) / cos(x))))
end function
public static double code(double x, double eps) {
	double t_0 = Math.pow(Math.cos(x), 2.0);
	double t_1 = Math.pow(Math.sin(x), 2.0);
	return eps * (1.0 + ((1.0 / (t_0 / t_1)) - ((eps * (Math.sin(x) * (-1.0 - (t_1 / t_0)))) / Math.cos(x))));
}
def code(x, eps):
	t_0 = math.pow(math.cos(x), 2.0)
	t_1 = math.pow(math.sin(x), 2.0)
	return eps * (1.0 + ((1.0 / (t_0 / t_1)) - ((eps * (math.sin(x) * (-1.0 - (t_1 / t_0)))) / math.cos(x))))
function code(x, eps)
	t_0 = cos(x) ^ 2.0
	t_1 = sin(x) ^ 2.0
	return Float64(eps * Float64(1.0 + Float64(Float64(1.0 / Float64(t_0 / t_1)) - Float64(Float64(eps * Float64(sin(x) * Float64(-1.0 - Float64(t_1 / t_0)))) / cos(x)))))
end
function tmp = code(x, eps)
	t_0 = cos(x) ^ 2.0;
	t_1 = sin(x) ^ 2.0;
	tmp = eps * (1.0 + ((1.0 / (t_0 / t_1)) - ((eps * (sin(x) * (-1.0 - (t_1 / t_0)))) / cos(x))));
end
code[x_, eps_] := Block[{t$95$0 = N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(eps * N[(1.0 + N[(N[(1.0 / N[(t$95$0 / t$95$1), $MachinePrecision]), $MachinePrecision] - N[(N[(eps * N[(N[Sin[x], $MachinePrecision] * N[(-1.0 - N[(t$95$1 / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\cos x}^{2}\\
t_1 := {\sin x}^{2}\\
\varepsilon \cdot \left(1 + \left(\frac{1}{\frac{t\_0}{t\_1}} - \frac{\varepsilon \cdot \left(\sin x \cdot \left(-1 - \frac{t\_1}{t\_0}\right)\right)}{\cos x}\right)\right)
\end{array}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Step-by-step derivation
    1. clear-num99.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
    2. inv-pow99.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{{\left(\frac{{\cos x}^{2}}{{\sin x}^{2}}\right)}^{-1}}\right)\right)\right) \]
  6. Applied egg-rr99.1%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{{\left(\frac{{\cos x}^{2}}{{\sin x}^{2}}\right)}^{-1}}\right)\right)\right) \]
  7. Step-by-step derivation
    1. unpow-199.1%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
  8. Simplified99.1%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\color{blue}{\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}}\right)\right)\right) \]
  9. Taylor expanded in eps around 0 98.7%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\color{blue}{\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}} - \left(-\frac{1}{\frac{{\cos x}^{2}}{{\sin x}^{2}}}\right)\right)\right) \]
  10. Final simplification98.7%

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

Alternative 6: 99.4% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{{\sin x}^{2}}{{\cos x}^{2}}\\ \varepsilon \cdot \left(1 + \left(t\_0 - \varepsilon \cdot \left(\sin x \cdot \frac{-1 - t\_0}{\cos x}\right)\right)\right) \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (/ (pow (sin x) 2.0) (pow (cos 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(sin(x), 2.0) / pow(cos(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 = (sin(x) ** 2.0d0) / (cos(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.sin(x), 2.0) / Math.pow(Math.cos(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.sin(x), 2.0) / math.pow(math.cos(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 = Float64((sin(x) ^ 2.0) / (cos(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 = (sin(x) ^ 2.0) / (cos(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[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $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 := \frac{{\sin x}^{2}}{{\cos 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 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Taylor expanded in x around 0 98.9%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \color{blue}{\left(-1.3333333333333333 \cdot {x}^{2} - 0.3333333333333333\right)} - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) \]
  6. Taylor expanded in eps around 0 98.7%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\frac{\varepsilon \cdot \left(\sin x \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x} + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
  7. Simplified98.7%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \varepsilon \cdot \left(\sin x \cdot \frac{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}{\cos x}\right)\right)\right)} \]
  8. Final simplification98.7%

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

Alternative 7: 99.0% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \varepsilon \cdot \left(1 + \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \varepsilon \cdot \left(x + \varepsilon \cdot 0.3333333333333333\right)\right)\right) \end{array} \]
(FPCore (x eps)
 :precision binary64
 (*
  eps
  (+
   1.0
   (+
    (/ (pow (sin x) 2.0) (pow (cos x) 2.0))
    (* eps (+ x (* eps 0.3333333333333333)))))))
double code(double x, double eps) {
	return eps * (1.0 + ((pow(sin(x), 2.0) / pow(cos(x), 2.0)) + (eps * (x + (eps * 0.3333333333333333)))));
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = eps * (1.0d0 + (((sin(x) ** 2.0d0) / (cos(x) ** 2.0d0)) + (eps * (x + (eps * 0.3333333333333333d0)))))
end function
public static double code(double x, double eps) {
	return eps * (1.0 + ((Math.pow(Math.sin(x), 2.0) / Math.pow(Math.cos(x), 2.0)) + (eps * (x + (eps * 0.3333333333333333)))));
}
def code(x, eps):
	return eps * (1.0 + ((math.pow(math.sin(x), 2.0) / math.pow(math.cos(x), 2.0)) + (eps * (x + (eps * 0.3333333333333333)))))
function code(x, eps)
	return Float64(eps * Float64(1.0 + Float64(Float64((sin(x) ^ 2.0) / (cos(x) ^ 2.0)) + Float64(eps * Float64(x + Float64(eps * 0.3333333333333333))))))
end
function tmp = code(x, eps)
	tmp = eps * (1.0 + (((sin(x) ^ 2.0) / (cos(x) ^ 2.0)) + (eps * (x + (eps * 0.3333333333333333)))));
end
code[x_, eps_] := N[(eps * N[(1.0 + N[(N[(N[Power[N[Sin[x], $MachinePrecision], 2.0], $MachinePrecision] / N[Power[N[Cos[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] + N[(eps * N[(x + N[(eps * 0.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\varepsilon \cdot \left(1 + \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \varepsilon \cdot \left(x + \varepsilon \cdot 0.3333333333333333\right)\right)\right)
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(\left(1 + \varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \left(-1 \cdot \frac{{\sin x}^{2} \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}} + \left(-0.5 \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right) + 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)\right) - -1 \cdot \frac{\sin x \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{\cos x}\right)\right) - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  4. Simplified99.1%

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(-1 \cdot \left(\varepsilon \cdot \left(0.16666666666666666 + \mathsf{fma}\left(-1, {\sin x}^{2} \cdot \frac{1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}{{\cos x}^{2}}, \mathsf{fma}\left(-0.5, 1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right), 0.16666666666666666 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) - \frac{\sin x \cdot \left(1 - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}{\cos x}\right)\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
  5. Taylor expanded in x around 0 98.3%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \color{blue}{\left(x + 0.3333333333333333 \cdot \varepsilon\right)} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) \]
  6. Step-by-step derivation
    1. *-commutative98.3%

      \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \left(x + \color{blue}{\varepsilon \cdot 0.3333333333333333}\right) - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) \]
  7. Simplified98.3%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\varepsilon \cdot \color{blue}{\left(x + \varepsilon \cdot 0.3333333333333333\right)} - \left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right) \]
  8. Final simplification98.3%

    \[\leadsto \varepsilon \cdot \left(1 + \left(\frac{{\sin x}^{2}}{{\cos x}^{2}} + \varepsilon \cdot \left(x + \varepsilon \cdot 0.3333333333333333\right)\right)\right) \]
  9. Add Preprocessing

Alternative 8: 98.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \tan \left(\varepsilon + x\right) - \tan x\\ \mathbf{if}\;t\_0 \leq 5 \cdot 10^{-15}:\\ \;\;\;\;\varepsilon + \varepsilon \cdot {x}^{2}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (- (tan (+ eps x)) (tan x))))
   (if (<= t_0 5e-15) (+ eps (* eps (pow x 2.0))) t_0)))
double code(double x, double eps) {
	double t_0 = tan((eps + x)) - tan(x);
	double tmp;
	if (t_0 <= 5e-15) {
		tmp = eps + (eps * pow(x, 2.0));
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: tmp
    t_0 = tan((eps + x)) - tan(x)
    if (t_0 <= 5d-15) then
        tmp = eps + (eps * (x ** 2.0d0))
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double t_0 = Math.tan((eps + x)) - Math.tan(x);
	double tmp;
	if (t_0 <= 5e-15) {
		tmp = eps + (eps * Math.pow(x, 2.0));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, eps):
	t_0 = math.tan((eps + x)) - math.tan(x)
	tmp = 0
	if t_0 <= 5e-15:
		tmp = eps + (eps * math.pow(x, 2.0))
	else:
		tmp = t_0
	return tmp
function code(x, eps)
	t_0 = Float64(tan(Float64(eps + x)) - tan(x))
	tmp = 0.0
	if (t_0 <= 5e-15)
		tmp = Float64(eps + Float64(eps * (x ^ 2.0)));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = tan((eps + x)) - tan(x);
	tmp = 0.0;
	if (t_0 <= 5e-15)
		tmp = eps + (eps * (x ^ 2.0));
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, eps_] := Block[{t$95$0 = N[(N[Tan[N[(eps + x), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 5e-15], N[(eps + N[(eps * N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \tan \left(\varepsilon + x\right) - \tan x\\
\mathbf{if}\;t\_0 \leq 5 \cdot 10^{-15}:\\
\;\;\;\;\varepsilon + \varepsilon \cdot {x}^{2}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (tan.f64 (+.f64 x eps)) (tan.f64 x)) < 4.99999999999999999e-15

    1. Initial program 61.0%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0 100.0%

      \[\leadsto \color{blue}{\varepsilon \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(--1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)} \]
      2. mul-1-neg100.0%

        \[\leadsto \varepsilon \cdot \left(1 + \left(-\color{blue}{\left(-\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)}\right)\right) \]
      3. remove-double-neg100.0%

        \[\leadsto \varepsilon \cdot \left(1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}\right) \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    6. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\varepsilon + \varepsilon \cdot {x}^{2}} \]

    if 4.99999999999999999e-15 < (-.f64 (tan.f64 (+.f64 x eps)) (tan.f64 x))

    1. Initial program 73.2%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification98.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\tan \left(\varepsilon + x\right) - \tan x \leq 5 \cdot 10^{-15}:\\ \;\;\;\;\varepsilon + \varepsilon \cdot {x}^{2}\\ \mathbf{else}:\\ \;\;\;\;\tan \left(\varepsilon + x\right) - \tan x\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 99.0% accurate, 1.0× speedup?

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

\\
\varepsilon + \varepsilon \cdot {\tan x}^{2}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.2%

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

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

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

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

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  6. Step-by-step derivation
    1. log1p-expm1-u98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
    2. log1p-undefine98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  7. Applied egg-rr98.2%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  8. Step-by-step derivation
    1. +-commutative98.2%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{{\sin x}^{2}}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)} + 1\right)} \]
    2. distribute-lft-in98.2%

      \[\leadsto \color{blue}{\varepsilon \cdot \frac{{\sin x}^{2}}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)} + \varepsilon \cdot 1} \]
    3. log1p-define98.2%

      \[\leadsto \varepsilon \cdot \frac{{\sin x}^{2}}{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left({\cos x}^{2}\right)\right)}} + \varepsilon \cdot 1 \]
    4. log1p-expm1-u98.2%

      \[\leadsto \varepsilon \cdot \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}} + \varepsilon \cdot 1 \]
    5. unpow298.2%

      \[\leadsto \varepsilon \cdot \frac{{\sin x}^{2}}{\color{blue}{\cos x \cdot \cos x}} + \varepsilon \cdot 1 \]
    6. unpow298.2%

      \[\leadsto \varepsilon \cdot \frac{\color{blue}{\sin x \cdot \sin x}}{\cos x \cdot \cos x} + \varepsilon \cdot 1 \]
    7. frac-times98.2%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(\frac{\sin x}{\cos x} \cdot \frac{\sin x}{\cos x}\right)} + \varepsilon \cdot 1 \]
    8. tan-quot98.2%

      \[\leadsto \varepsilon \cdot \left(\frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}\right) + \varepsilon \cdot 1 \]
    9. tan-quot98.2%

      \[\leadsto \varepsilon \cdot \left(\color{blue}{\tan x} \cdot \tan x\right) + \varepsilon \cdot 1 \]
    10. pow298.2%

      \[\leadsto \varepsilon \cdot \color{blue}{{\tan x}^{2}} + \varepsilon \cdot 1 \]
    11. *-rgt-identity98.2%

      \[\leadsto \varepsilon \cdot {\tan x}^{2} + \color{blue}{\varepsilon} \]
  9. Applied egg-rr98.2%

    \[\leadsto \color{blue}{\varepsilon \cdot {\tan x}^{2} + \varepsilon} \]
  10. Final simplification98.2%

    \[\leadsto \varepsilon + \varepsilon \cdot {\tan x}^{2} \]
  11. Add Preprocessing

Alternative 10: 99.0% accurate, 1.0× speedup?

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

\\
\varepsilon \cdot \left(1 + {\tan x}^{2}\right)
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.2%

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

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

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

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

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  6. Step-by-step derivation
    1. log1p-expm1-u98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
    2. log1p-undefine98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  7. Applied egg-rr98.2%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  8. Step-by-step derivation
    1. *-un-lft-identity98.2%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 \cdot \left(1 + \frac{{\sin x}^{2}}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}\right)\right)} \]
    2. log1p-define98.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right)\right) \]
    3. log1p-expm1-u98.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}\right)\right) \]
    4. unpow298.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\cos x \cdot \cos x}}\right)\right) \]
    5. unpow298.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \frac{\color{blue}{\sin x \cdot \sin x}}{\cos x \cdot \cos x}\right)\right) \]
    6. frac-times98.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \color{blue}{\frac{\sin x}{\cos x} \cdot \frac{\sin x}{\cos x}}\right)\right) \]
    7. tan-quot98.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}\right)\right) \]
    8. tan-quot98.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \color{blue}{\tan x} \cdot \tan x\right)\right) \]
    9. pow298.2%

      \[\leadsto \varepsilon \cdot \left(1 \cdot \left(1 + \color{blue}{{\tan x}^{2}}\right)\right) \]
  9. Applied egg-rr98.2%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(1 \cdot \left(1 + {\tan x}^{2}\right)\right)} \]
  10. Step-by-step derivation
    1. *-lft-identity98.2%

      \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + {\tan x}^{2}\right)} \]
  11. Simplified98.2%

    \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + {\tan x}^{2}\right)} \]
  12. Add Preprocessing

Alternative 11: 98.3% accurate, 1.9× speedup?

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

\\
\varepsilon + \varepsilon \cdot {x}^{2}
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.2%

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

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

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

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

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

    \[\leadsto \color{blue}{\varepsilon + \varepsilon \cdot {x}^{2}} \]
  7. Add Preprocessing

Alternative 12: 98.3% accurate, 2.0× speedup?

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

\\
\varepsilon \cdot \mathsf{fma}\left(x, x, 1\right)
\end{array}
Derivation
  1. Initial program 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in eps around 0 98.2%

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

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

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

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

    \[\leadsto \color{blue}{\varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
  6. Step-by-step derivation
    1. log1p-expm1-u98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
    2. log1p-undefine98.2%

      \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  7. Applied egg-rr98.2%

    \[\leadsto \varepsilon \cdot \left(1 + \frac{{\sin x}^{2}}{\color{blue}{\log \left(1 + \mathsf{expm1}\left({\cos x}^{2}\right)\right)}}\right) \]
  8. Taylor expanded in x around 0 97.3%

    \[\leadsto \color{blue}{\varepsilon + \varepsilon \cdot {x}^{2}} \]
  9. Step-by-step derivation
    1. *-commutative97.3%

      \[\leadsto \varepsilon + \color{blue}{{x}^{2} \cdot \varepsilon} \]
    2. distribute-rgt1-in97.3%

      \[\leadsto \color{blue}{\left({x}^{2} + 1\right) \cdot \varepsilon} \]
    3. unpow297.3%

      \[\leadsto \left(\color{blue}{x \cdot x} + 1\right) \cdot \varepsilon \]
    4. fma-define97.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, 1\right)} \cdot \varepsilon \]
  10. Simplified97.3%

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, 1\right) \cdot \varepsilon} \]
  11. Final simplification97.3%

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

Alternative 13: 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 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 96.9%

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
  4. Step-by-step derivation
    1. *-un-lft-identity96.9%

      \[\leadsto \color{blue}{1 \cdot \frac{\sin \varepsilon}{\cos \varepsilon}} \]
    2. quot-tan96.9%

      \[\leadsto 1 \cdot \color{blue}{\tan \varepsilon} \]
  5. Applied egg-rr96.9%

    \[\leadsto \color{blue}{1 \cdot \tan \varepsilon} \]
  6. Step-by-step derivation
    1. *-lft-identity96.9%

      \[\leadsto \color{blue}{\tan \varepsilon} \]
  7. Simplified96.9%

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

Alternative 14: 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 61.5%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 96.9%

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \]
  4. Taylor expanded in eps around 0 96.9%

    \[\leadsto \color{blue}{\varepsilon} \]
  5. 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}

Reproduce

?
herbie shell --seed 2024144 
(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)))))

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