Trigonometry B

Percentage Accurate: 99.5% → 99.5%
Time: 12.0s
Alternatives: 9
Speedup: 1.0×

Specification

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

\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 9 alternatives:

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

Initial Program: 99.5% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}

Alternative 1: 99.5% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - {\tan x}^{2}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (fma (tan x) (tan x) -1.0) (- -1.0 (pow (tan x) 2.0))))
double code(double x) {
	return fma(tan(x), tan(x), -1.0) / (-1.0 - pow(tan(x), 2.0));
}
function code(x)
	return Float64(fma(tan(x), tan(x), -1.0) / Float64(-1.0 - (tan(x) ^ 2.0)))
end
code[x_] := N[(N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + -1.0), $MachinePrecision] / N[(-1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - {\tan x}^{2}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. /-rgt-identity99.5%

      \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
    2. div-sub99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
    3. sub-neg99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    4. +-commutative99.3%

      \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
    5. neg-sub099.3%

      \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
    6. associate-+l-99.3%

      \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    7. sub0-neg99.3%

      \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    8. neg-mul-199.3%

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

      \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
  4. Step-by-step derivation
    1. expm1-log1p-u99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
    2. log1p-def99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
    3. expm1-udef99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
    4. add-exp-log99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
    5. +-commutative99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
    6. associate--l+99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
    7. pow299.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
    8. metadata-eval99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
  5. Applied egg-rr99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
  6. Step-by-step derivation
    1. +-rgt-identity99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  7. Simplified99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  8. Final simplification99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - {\tan x}^{2}} \]

Alternative 2: 99.5% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
t_0 := \frac{\tan x}{\frac{1}{\tan x}}\\
\frac{1 - t_0}{1 + t_0}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. frac-2neg99.5%

      \[\leadsto \color{blue}{\frac{-\left(1 - \tan x \cdot \tan x\right)}{-\left(1 + \tan x \cdot \tan x\right)}} \]
    2. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    3. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    4. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    5. distribute-neg-in99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{\left(-\tan x \cdot \tan x\right) + \left(-1\right)}} \]
    6. metadata-eval99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\left(-\tan x \cdot \tan x\right) + \color{blue}{-1}} \]
    7. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 + \left(-\tan x \cdot \tan x\right)}} \]
    8. sub-neg99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
    9. distribute-frac-neg99.5%

      \[\leadsto \color{blue}{-\frac{1 - \tan x \cdot \tan x}{-1 - \tan x \cdot \tan x}} \]
    10. flip--99.4%

      \[\leadsto -\frac{\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{1 + \tan x \cdot \tan x}}}{-1 - \tan x \cdot \tan x} \]
    11. associate-/l/99.3%

      \[\leadsto -\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{\left(-1 - \tan x \cdot \tan x\right) \cdot \left(1 + \tan x \cdot \tan x\right)}} \]
  3. Applied egg-rr99.5%

    \[\leadsto \color{blue}{-\frac{{\tan x}^{2} + -1}{{\tan x}^{2} + 1}} \]
  4. Step-by-step derivation
    1. distribute-neg-frac99.5%

      \[\leadsto \color{blue}{\frac{-\left({\tan x}^{2} + -1\right)}{{\tan x}^{2} + 1}} \]
    2. distribute-neg-in99.5%

      \[\leadsto \frac{\color{blue}{\left(-{\tan x}^{2}\right) + \left(--1\right)}}{{\tan x}^{2} + 1} \]
    3. metadata-eval99.5%

      \[\leadsto \frac{\left(-{\tan x}^{2}\right) + \color{blue}{1}}{{\tan x}^{2} + 1} \]
    4. +-commutative99.5%

      \[\leadsto \frac{\color{blue}{1 + \left(-{\tan x}^{2}\right)}}{{\tan x}^{2} + 1} \]
    5. sub-neg99.5%

      \[\leadsto \frac{\color{blue}{1 - {\tan x}^{2}}}{{\tan x}^{2} + 1} \]
    6. +-commutative99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + {\tan x}^{2}}} \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{\frac{1 - {\tan x}^{2}}{1 + {\tan x}^{2}}} \]
  6. Step-by-step derivation
    1. unpow299.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. tan-quot99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \tan x \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    3. associate-*r/99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x \cdot \sin x}{\cos x}}} \]
    4. associate-/l*99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x}{\frac{\cos x}{\sin x}}}} \]
    5. clear-num99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\color{blue}{\frac{1}{\frac{\sin x}{\cos x}}}}} \]
    6. tan-quot99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\frac{1}{\color{blue}{\tan x}}}} \]
  7. Applied egg-rr99.5%

    \[\leadsto \frac{1 - \color{blue}{\frac{\tan x}{\frac{1}{\tan x}}}}{1 + {\tan x}^{2}} \]
  8. Step-by-step derivation
    1. unpow299.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. tan-quot99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \tan x \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    3. associate-*r/99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x \cdot \sin x}{\cos x}}} \]
    4. associate-/l*99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x}{\frac{\cos x}{\sin x}}}} \]
    5. clear-num99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\color{blue}{\frac{1}{\frac{\sin x}{\cos x}}}}} \]
    6. tan-quot99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\frac{1}{\color{blue}{\tan x}}}} \]
  9. Applied egg-rr99.5%

    \[\leadsto \frac{1 - \frac{\tan x}{\frac{1}{\tan x}}}{1 + \color{blue}{\frac{\tan x}{\frac{1}{\tan x}}}} \]
  10. Final simplification99.5%

    \[\leadsto \frac{1 - \frac{\tan x}{\frac{1}{\tan x}}}{1 + \frac{\tan x}{\frac{1}{\tan x}}} \]

Alternative 3: 60.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\tan x \cdot \tan x \leq 1:\\ \;\;\;\;\frac{-1}{1 + \left(-1 + \left(-1 - {\tan x}^{2}\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (* (tan x) (tan x)) 1.0)
   (/ -1.0 (+ 1.0 (+ -1.0 (- -1.0 (pow (tan x) 2.0)))))
   -1.0))
double code(double x) {
	double tmp;
	if ((tan(x) * tan(x)) <= 1.0) {
		tmp = -1.0 / (1.0 + (-1.0 + (-1.0 - pow(tan(x), 2.0))));
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if ((tan(x) * tan(x)) <= 1.0d0) then
        tmp = (-1.0d0) / (1.0d0 + ((-1.0d0) + ((-1.0d0) - (tan(x) ** 2.0d0))))
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if ((Math.tan(x) * Math.tan(x)) <= 1.0) {
		tmp = -1.0 / (1.0 + (-1.0 + (-1.0 - Math.pow(Math.tan(x), 2.0))));
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if (math.tan(x) * math.tan(x)) <= 1.0:
		tmp = -1.0 / (1.0 + (-1.0 + (-1.0 - math.pow(math.tan(x), 2.0))))
	else:
		tmp = -1.0
	return tmp
function code(x)
	tmp = 0.0
	if (Float64(tan(x) * tan(x)) <= 1.0)
		tmp = Float64(-1.0 / Float64(1.0 + Float64(-1.0 + Float64(-1.0 - (tan(x) ^ 2.0)))));
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if ((tan(x) * tan(x)) <= 1.0)
		tmp = -1.0 / (1.0 + (-1.0 + (-1.0 - (tan(x) ^ 2.0))));
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision], 1.0], N[(-1.0 / N[(1.0 + N[(-1.0 + N[(-1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\tan x \cdot \tan x \leq 1:\\
\;\;\;\;\frac{-1}{1 + \left(-1 + \left(-1 - {\tan x}^{2}\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 (tan.f64 x) (tan.f64 x)) < 1

    1. Initial program 99.6%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.6%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.4%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.4%

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

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.4%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.4%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.4%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.4%

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

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 70.4%

      \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
    9. Step-by-step derivation
      1. expm1-log1p-u70.4%

        \[\leadsto \frac{-1}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\tan x}^{2}\right)\right)}} \]
      2. log1p-def70.4%

        \[\leadsto \frac{-1}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + {\tan x}^{2}\right)}\right)} \]
      3. expm1-udef70.4%

        \[\leadsto \frac{-1}{-1 - \color{blue}{\left(e^{\log \left(1 + {\tan x}^{2}\right)} - 1\right)}} \]
      4. add-exp-log70.4%

        \[\leadsto \frac{-1}{-1 - \left(\color{blue}{\left(1 + {\tan x}^{2}\right)} - 1\right)} \]
      5. associate--r-70.4%

        \[\leadsto \frac{-1}{\color{blue}{\left(-1 - \left(1 + {\tan x}^{2}\right)\right) + 1}} \]
      6. +-commutative70.4%

        \[\leadsto \frac{-1}{\left(-1 - \color{blue}{\left({\tan x}^{2} + 1\right)}\right) + 1} \]
    10. Applied egg-rr70.4%

      \[\leadsto \frac{-1}{\color{blue}{\left(-1 - \left({\tan x}^{2} + 1\right)\right) + 1}} \]

    if 1 < (*.f64 (tan.f64 x) (tan.f64 x))

    1. Initial program 99.2%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.2%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      4. +-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.0%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.0%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.0%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      9. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef98.7%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 1.6%

      \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
    9. Applied egg-rr17.3%

      \[\leadsto \frac{-1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    10. Taylor expanded in x around 0 20.7%

      \[\leadsto \color{blue}{-1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification58.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\tan x \cdot \tan x \leq 1:\\ \;\;\;\;\frac{-1}{1 + \left(-1 + \left(-1 - {\tan x}^{2}\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]

Alternative 4: 60.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\tan x \cdot \tan x \leq 1:\\ \;\;\;\;\frac{-1}{-1 - {\tan x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (* (tan x) (tan x)) 1.0) (/ -1.0 (- -1.0 (pow (tan x) 2.0))) -1.0))
double code(double x) {
	double tmp;
	if ((tan(x) * tan(x)) <= 1.0) {
		tmp = -1.0 / (-1.0 - pow(tan(x), 2.0));
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if ((tan(x) * tan(x)) <= 1.0d0) then
        tmp = (-1.0d0) / ((-1.0d0) - (tan(x) ** 2.0d0))
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if ((Math.tan(x) * Math.tan(x)) <= 1.0) {
		tmp = -1.0 / (-1.0 - Math.pow(Math.tan(x), 2.0));
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if (math.tan(x) * math.tan(x)) <= 1.0:
		tmp = -1.0 / (-1.0 - math.pow(math.tan(x), 2.0))
	else:
		tmp = -1.0
	return tmp
function code(x)
	tmp = 0.0
	if (Float64(tan(x) * tan(x)) <= 1.0)
		tmp = Float64(-1.0 / Float64(-1.0 - (tan(x) ^ 2.0)));
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if ((tan(x) * tan(x)) <= 1.0)
		tmp = -1.0 / (-1.0 - (tan(x) ^ 2.0));
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision], 1.0], N[(-1.0 / N[(-1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -1.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\tan x \cdot \tan x \leq 1:\\
\;\;\;\;\frac{-1}{-1 - {\tan x}^{2}}\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 (tan.f64 x) (tan.f64 x)) < 1

    1. Initial program 99.6%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.6%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.4%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.4%

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

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.4%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.4%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.4%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.4%

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

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 70.4%

      \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]

    if 1 < (*.f64 (tan.f64 x) (tan.f64 x))

    1. Initial program 99.2%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.2%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      4. +-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.0%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.0%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.0%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      9. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef98.7%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 1.6%

      \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
    9. Applied egg-rr17.3%

      \[\leadsto \frac{-1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    10. Taylor expanded in x around 0 20.7%

      \[\leadsto \color{blue}{-1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification58.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\tan x \cdot \tan x \leq 1:\\ \;\;\;\;\frac{-1}{-1 - {\tan x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]

Alternative 5: 99.5% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\frac{1 - t_0}{t_0 + 1}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. frac-2neg99.5%

      \[\leadsto \color{blue}{\frac{-\left(1 - \tan x \cdot \tan x\right)}{-\left(1 + \tan x \cdot \tan x\right)}} \]
    2. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    3. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    4. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    5. distribute-neg-in99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{\left(-\tan x \cdot \tan x\right) + \left(-1\right)}} \]
    6. metadata-eval99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\left(-\tan x \cdot \tan x\right) + \color{blue}{-1}} \]
    7. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 + \left(-\tan x \cdot \tan x\right)}} \]
    8. sub-neg99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
    9. distribute-frac-neg99.5%

      \[\leadsto \color{blue}{-\frac{1 - \tan x \cdot \tan x}{-1 - \tan x \cdot \tan x}} \]
    10. flip--99.4%

      \[\leadsto -\frac{\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{1 + \tan x \cdot \tan x}}}{-1 - \tan x \cdot \tan x} \]
    11. associate-/l/99.3%

      \[\leadsto -\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{\left(-1 - \tan x \cdot \tan x\right) \cdot \left(1 + \tan x \cdot \tan x\right)}} \]
  3. Applied egg-rr99.5%

    \[\leadsto \color{blue}{-\frac{{\tan x}^{2} + -1}{{\tan x}^{2} + 1}} \]
  4. Step-by-step derivation
    1. distribute-neg-frac99.5%

      \[\leadsto \color{blue}{\frac{-\left({\tan x}^{2} + -1\right)}{{\tan x}^{2} + 1}} \]
    2. distribute-neg-in99.5%

      \[\leadsto \frac{\color{blue}{\left(-{\tan x}^{2}\right) + \left(--1\right)}}{{\tan x}^{2} + 1} \]
    3. metadata-eval99.5%

      \[\leadsto \frac{\left(-{\tan x}^{2}\right) + \color{blue}{1}}{{\tan x}^{2} + 1} \]
    4. +-commutative99.5%

      \[\leadsto \frac{\color{blue}{1 + \left(-{\tan x}^{2}\right)}}{{\tan x}^{2} + 1} \]
    5. sub-neg99.5%

      \[\leadsto \frac{\color{blue}{1 - {\tan x}^{2}}}{{\tan x}^{2} + 1} \]
    6. +-commutative99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + {\tan x}^{2}}} \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{\frac{1 - {\tan x}^{2}}{1 + {\tan x}^{2}}} \]
  6. Final simplification99.5%

    \[\leadsto \frac{1 - {\tan x}^{2}}{{\tan x}^{2} + 1} \]

Alternative 6: 59.7% accurate, 1.3× speedup?

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

\\
\frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{x \cdot -0.3333333333333333 + \frac{1}{x}}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. frac-2neg99.5%

      \[\leadsto \color{blue}{\frac{-\left(1 - \tan x \cdot \tan x\right)}{-\left(1 + \tan x \cdot \tan x\right)}} \]
    2. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    3. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    4. fma-udef99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    5. distribute-neg-in99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{\left(-\tan x \cdot \tan x\right) + \left(-1\right)}} \]
    6. metadata-eval99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\left(-\tan x \cdot \tan x\right) + \color{blue}{-1}} \]
    7. +-commutative99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 + \left(-\tan x \cdot \tan x\right)}} \]
    8. sub-neg99.5%

      \[\leadsto \frac{-\left(1 - \tan x \cdot \tan x\right)}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
    9. distribute-frac-neg99.5%

      \[\leadsto \color{blue}{-\frac{1 - \tan x \cdot \tan x}{-1 - \tan x \cdot \tan x}} \]
    10. flip--99.4%

      \[\leadsto -\frac{\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{1 + \tan x \cdot \tan x}}}{-1 - \tan x \cdot \tan x} \]
    11. associate-/l/99.3%

      \[\leadsto -\color{blue}{\frac{1 \cdot 1 - \left(\tan x \cdot \tan x\right) \cdot \left(\tan x \cdot \tan x\right)}{\left(-1 - \tan x \cdot \tan x\right) \cdot \left(1 + \tan x \cdot \tan x\right)}} \]
  3. Applied egg-rr99.5%

    \[\leadsto \color{blue}{-\frac{{\tan x}^{2} + -1}{{\tan x}^{2} + 1}} \]
  4. Step-by-step derivation
    1. distribute-neg-frac99.5%

      \[\leadsto \color{blue}{\frac{-\left({\tan x}^{2} + -1\right)}{{\tan x}^{2} + 1}} \]
    2. distribute-neg-in99.5%

      \[\leadsto \frac{\color{blue}{\left(-{\tan x}^{2}\right) + \left(--1\right)}}{{\tan x}^{2} + 1} \]
    3. metadata-eval99.5%

      \[\leadsto \frac{\left(-{\tan x}^{2}\right) + \color{blue}{1}}{{\tan x}^{2} + 1} \]
    4. +-commutative99.5%

      \[\leadsto \frac{\color{blue}{1 + \left(-{\tan x}^{2}\right)}}{{\tan x}^{2} + 1} \]
    5. sub-neg99.5%

      \[\leadsto \frac{\color{blue}{1 - {\tan x}^{2}}}{{\tan x}^{2} + 1} \]
    6. +-commutative99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + {\tan x}^{2}}} \]
  5. Simplified99.5%

    \[\leadsto \color{blue}{\frac{1 - {\tan x}^{2}}{1 + {\tan x}^{2}}} \]
  6. Step-by-step derivation
    1. unpow299.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. tan-quot99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \tan x \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    3. associate-*r/99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x \cdot \sin x}{\cos x}}} \]
    4. associate-/l*99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x}{\frac{\cos x}{\sin x}}}} \]
    5. clear-num99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\color{blue}{\frac{1}{\frac{\sin x}{\cos x}}}}} \]
    6. tan-quot99.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\frac{1}{\color{blue}{\tan x}}}} \]
  7. Applied egg-rr99.5%

    \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{\tan x}{\frac{1}{\tan x}}}} \]
  8. Taylor expanded in x around 0 57.4%

    \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{\color{blue}{-0.3333333333333333 \cdot x + \frac{1}{x}}}} \]
  9. Final simplification57.4%

    \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{\tan x}{x \cdot -0.3333333333333333 + \frac{1}{x}}} \]

Alternative 7: 59.3% accurate, 1.3× speedup?

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

\\
\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. /-rgt-identity99.5%

      \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
    2. div-sub99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
    3. sub-neg99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    4. +-commutative99.3%

      \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
    5. neg-sub099.3%

      \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
    6. associate-+l-99.3%

      \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    7. sub0-neg99.3%

      \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    8. neg-mul-199.3%

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

      \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
  4. Step-by-step derivation
    1. expm1-log1p-u99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
    2. log1p-def99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
    3. expm1-udef99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
    4. add-exp-log99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
    5. +-commutative99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
    6. associate--l+99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
    7. pow299.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
    8. metadata-eval99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
  5. Applied egg-rr99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
  6. Step-by-step derivation
    1. +-rgt-identity99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  7. Simplified99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  8. Taylor expanded in x around 0 57.2%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{\color{blue}{-1}} \]
  9. Final simplification57.2%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1} \]

Alternative 8: 60.0% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\tan x \leq -1:\\ \;\;\;\;-1\\ \mathbf{elif}\;\tan x \leq 1:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (tan x) -1.0) -1.0 (if (<= (tan x) 1.0) 1.0 -1.0)))
double code(double x) {
	double tmp;
	if (tan(x) <= -1.0) {
		tmp = -1.0;
	} else if (tan(x) <= 1.0) {
		tmp = 1.0;
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (tan(x) <= (-1.0d0)) then
        tmp = -1.0d0
    else if (tan(x) <= 1.0d0) then
        tmp = 1.0d0
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (Math.tan(x) <= -1.0) {
		tmp = -1.0;
	} else if (Math.tan(x) <= 1.0) {
		tmp = 1.0;
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if math.tan(x) <= -1.0:
		tmp = -1.0
	elif math.tan(x) <= 1.0:
		tmp = 1.0
	else:
		tmp = -1.0
	return tmp
function code(x)
	tmp = 0.0
	if (tan(x) <= -1.0)
		tmp = -1.0;
	elseif (tan(x) <= 1.0)
		tmp = 1.0;
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (tan(x) <= -1.0)
		tmp = -1.0;
	elseif (tan(x) <= 1.0)
		tmp = 1.0;
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[N[Tan[x], $MachinePrecision], -1.0], -1.0, If[LessEqual[N[Tan[x], $MachinePrecision], 1.0], 1.0, -1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\tan x \leq -1:\\
\;\;\;\;-1\\

\mathbf{elif}\;\tan x \leq 1:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (tan.f64 x) < -1 or 1 < (tan.f64 x)

    1. Initial program 99.2%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.2%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.0%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      4. +-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.0%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.0%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.0%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      9. *-commutative99.0%

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def98.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef98.7%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 1.6%

      \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
    9. Applied egg-rr17.3%

      \[\leadsto \frac{-1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    10. Taylor expanded in x around 0 20.7%

      \[\leadsto \color{blue}{-1} \]

    if -1 < (tan.f64 x) < 1

    1. Initial program 99.6%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. /-rgt-identity99.6%

        \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
      2. div-sub99.4%

        \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
      3. sub-neg99.4%

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

        \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
      5. neg-sub099.4%

        \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
      6. associate-+l-99.4%

        \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      7. sub0-neg99.4%

        \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
      8. neg-mul-199.4%

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

        \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
    4. Step-by-step derivation
      1. expm1-log1p-u99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
      2. log1p-def99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
      3. expm1-udef99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
      4. add-exp-log99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
      5. +-commutative99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
      6. associate--l+99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
      7. pow299.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
      8. metadata-eval99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
    5. Applied egg-rr99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identity99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    7. Simplified99.6%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
    8. Taylor expanded in x around 0 69.9%

      \[\leadsto \color{blue}{1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification57.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\tan x \leq -1:\\ \;\;\;\;-1\\ \mathbf{elif}\;\tan x \leq 1:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]

Alternative 9: 6.5% accurate, 411.0× speedup?

\[\begin{array}{l} \\ -1 \end{array} \]
(FPCore (x) :precision binary64 -1.0)
double code(double x) {
	return -1.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = -1.0d0
end function
public static double code(double x) {
	return -1.0;
}
def code(x):
	return -1.0
function code(x)
	return -1.0
end
function tmp = code(x)
	tmp = -1.0;
end
code[x_] := -1.0
\begin{array}{l}

\\
-1
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. /-rgt-identity99.5%

      \[\leadsto \color{blue}{\frac{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}{1}} \]
    2. div-sub99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}}}{1} \]
    3. sub-neg99.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{1 + \tan x \cdot \tan x} + \left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    4. +-commutative99.3%

      \[\leadsto \frac{\color{blue}{\left(-\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right) + \frac{1}{1 + \tan x \cdot \tan x}}}{1} \]
    5. neg-sub099.3%

      \[\leadsto \frac{\color{blue}{\left(0 - \frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} + \frac{1}{1 + \tan x \cdot \tan x}}{1} \]
    6. associate-+l-99.3%

      \[\leadsto \frac{\color{blue}{0 - \left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    7. sub0-neg99.3%

      \[\leadsto \frac{\color{blue}{-\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right)}}{1} \]
    8. neg-mul-199.3%

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

      \[\leadsto \frac{\color{blue}{\left(\frac{\tan x \cdot \tan x}{1 + \tan x \cdot \tan x} - \frac{1}{1 + \tan x \cdot \tan x}\right) \cdot -1}}{1} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \tan x \cdot \tan x}} \]
  4. Step-by-step derivation
    1. expm1-log1p-u99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\tan x \cdot \tan x\right)\right)}} \]
    2. log1p-def99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \mathsf{expm1}\left(\color{blue}{\log \left(1 + \tan x \cdot \tan x\right)}\right)} \]
    3. expm1-udef99.3%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(e^{\log \left(1 + \tan x \cdot \tan x\right)} - 1\right)}} \]
    4. add-exp-log99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)} - 1\right)} \]
    5. +-commutative99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{\left(\tan x \cdot \tan x + 1\right)} - 1\right)} \]
    6. associate--l+99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left(\tan x \cdot \tan x + \left(1 - 1\right)\right)}} \]
    7. pow299.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left(\color{blue}{{\tan x}^{2}} + \left(1 - 1\right)\right)} \]
    8. metadata-eval99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \left({\tan x}^{2} + \color{blue}{0}\right)} \]
  5. Applied egg-rr99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{\left({\tan x}^{2} + 0\right)}} \]
  6. Step-by-step derivation
    1. +-rgt-identity99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  7. Simplified99.5%

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, \tan x, -1\right)}{-1 - \color{blue}{{\tan x}^{2}}} \]
  8. Taylor expanded in x around 0 53.2%

    \[\leadsto \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
  9. Applied egg-rr5.5%

    \[\leadsto \frac{-1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
  10. Taylor expanded in x around 0 6.4%

    \[\leadsto \color{blue}{-1} \]
  11. Final simplification6.4%

    \[\leadsto -1 \]

Reproduce

?
herbie shell --seed 2023301 
(FPCore (x)
  :name "Trigonometry B"
  :precision binary64
  (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))