Trigonometry B

Percentage Accurate: 99.5% → 99.5%
Time: 13.1s
Alternatives: 8
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 8 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), Float64(-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. sub-neg99.5%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    4. fma-def99.5%

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

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. add-log-exp98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    5. add-log-exp99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
    6. pow299.5%

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

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
  6. Step-by-step derivation
    1. +-lft-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, 0.8× speedup?

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

\\
\frac{1 - {\tan x}^{2}}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}
\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. +-commutative99.5%

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    2. fma-def99.5%

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

    \[\leadsto \color{blue}{\frac{1 - \tan x \cdot \tan x}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
  4. Step-by-step derivation
    1. add-log-exp98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    5. add-log-exp99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
    6. pow299.5%

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

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

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

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

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

Alternative 3: 59.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\tan x \leq -1 \lor \neg \left(\tan x \leq 1\right):\\ \;\;\;\;\frac{-1}{1 + {\tan x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (or (<= (tan x) -1.0) (not (<= (tan x) 1.0)))
   (/ -1.0 (+ 1.0 (pow (tan x) 2.0)))
   1.0))
double code(double x) {
	double tmp;
	if ((tan(x) <= -1.0) || !(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) <= (-1.0d0)) .or. (.not. (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) <= -1.0) || !(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) <= -1.0) or not (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 ((tan(x) <= -1.0) || !(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) <= -1.0) || ~((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[Or[LessEqual[N[Tan[x], $MachinePrecision], -1.0], N[Not[LessEqual[N[Tan[x], $MachinePrecision], 1.0]], $MachinePrecision]], 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 \leq -1 \lor \neg \left(\tan x \leq 1\right):\\
\;\;\;\;\frac{-1}{1 + {\tan x}^{2}}\\

\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 99.1%

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

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

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

        \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
      4. fma-def99.2%

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

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
    4. Step-by-step derivation
      1. add-log-exp96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
      2. *-un-lft-identity96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
      3. log-prod96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
      4. metadata-eval96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
      5. add-log-exp99.2%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
      6. pow299.2%

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

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

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

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

      \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
    9. Step-by-step derivation
      1. add-sqr-sqrt1.6%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{1 + {\tan x}^{2}}} \cdot \sqrt{\frac{1}{1 + {\tan x}^{2}}}} \]
      2. sqrt-unprod1.6%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{1 + {\tan x}^{2}} \cdot \frac{1}{1 + {\tan x}^{2}}}} \]
      3. frac-2neg1.6%

        \[\leadsto \sqrt{\color{blue}{\frac{-1}{-\left(1 + {\tan x}^{2}\right)}} \cdot \frac{1}{1 + {\tan x}^{2}}} \]
      4. metadata-eval1.6%

        \[\leadsto \sqrt{\frac{\color{blue}{-1}}{-\left(1 + {\tan x}^{2}\right)} \cdot \frac{1}{1 + {\tan x}^{2}}} \]
      5. associate-*l/1.6%

        \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot \frac{1}{1 + {\tan x}^{2}}}{-\left(1 + {\tan x}^{2}\right)}}} \]
    10. Applied egg-rr17.3%

      \[\leadsto \color{blue}{-1 \cdot \frac{1}{1 + {\tan x}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/17.3%

        \[\leadsto \color{blue}{\frac{-1 \cdot 1}{1 + {\tan x}^{2}}} \]
      2. metadata-eval17.3%

        \[\leadsto \frac{\color{blue}{-1}}{1 + {\tan x}^{2}} \]
    12. Simplified17.3%

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

    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. sub-neg99.6%

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

        \[\leadsto \frac{\color{blue}{\left(-\tan x \cdot \tan x\right) + 1}}{1 + \tan x \cdot \tan x} \]
      3. distribute-rgt-neg-in99.6%

        \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
      4. fma-def99.6%

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

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
    4. Step-by-step derivation
      1. add-log-exp99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
      2. *-un-lft-identity99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
      3. log-prod99.6%

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

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
      5. add-log-exp99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
      6. pow299.6%

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

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
    6. Step-by-step derivation
      1. +-lft-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 69.2%

      \[\leadsto \color{blue}{1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification55.5%

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

Alternative 4: 59.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + {\tan x}^{2}\\ \mathbf{if}\;\tan x \leq -1 \lor \neg \left(\tan x \leq 1\right):\\ \;\;\;\;\frac{-1}{t_0}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{t_0}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ 1.0 (pow (tan x) 2.0))))
   (if (or (<= (tan x) -1.0) (not (<= (tan x) 1.0)))
     (/ -1.0 t_0)
     (/ 1.0 t_0))))
double code(double x) {
	double t_0 = 1.0 + pow(tan(x), 2.0);
	double tmp;
	if ((tan(x) <= -1.0) || !(tan(x) <= 1.0)) {
		tmp = -1.0 / t_0;
	} else {
		tmp = 1.0 / t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = 1.0d0 + (tan(x) ** 2.0d0)
    if ((tan(x) <= (-1.0d0)) .or. (.not. (tan(x) <= 1.0d0))) then
        tmp = (-1.0d0) / t_0
    else
        tmp = 1.0d0 / t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = 1.0 + Math.pow(Math.tan(x), 2.0);
	double tmp;
	if ((Math.tan(x) <= -1.0) || !(Math.tan(x) <= 1.0)) {
		tmp = -1.0 / t_0;
	} else {
		tmp = 1.0 / t_0;
	}
	return tmp;
}
def code(x):
	t_0 = 1.0 + math.pow(math.tan(x), 2.0)
	tmp = 0
	if (math.tan(x) <= -1.0) or not (math.tan(x) <= 1.0):
		tmp = -1.0 / t_0
	else:
		tmp = 1.0 / t_0
	return tmp
function code(x)
	t_0 = Float64(1.0 + (tan(x) ^ 2.0))
	tmp = 0.0
	if ((tan(x) <= -1.0) || !(tan(x) <= 1.0))
		tmp = Float64(-1.0 / t_0);
	else
		tmp = Float64(1.0 / t_0);
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = 1.0 + (tan(x) ^ 2.0);
	tmp = 0.0;
	if ((tan(x) <= -1.0) || ~((tan(x) <= 1.0)))
		tmp = -1.0 / t_0;
	else
		tmp = 1.0 / t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(1.0 + N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[N[Tan[x], $MachinePrecision], -1.0], N[Not[LessEqual[N[Tan[x], $MachinePrecision], 1.0]], $MachinePrecision]], N[(-1.0 / t$95$0), $MachinePrecision], N[(1.0 / t$95$0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + {\tan x}^{2}\\
\mathbf{if}\;\tan x \leq -1 \lor \neg \left(\tan x \leq 1\right):\\
\;\;\;\;\frac{-1}{t_0}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{t_0}\\


\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 99.1%

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

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

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

        \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
      4. fma-def99.2%

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

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
    4. Step-by-step derivation
      1. add-log-exp96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
      2. *-un-lft-identity96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
      3. log-prod96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
      4. metadata-eval96.3%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
      5. add-log-exp99.2%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
      6. pow299.2%

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

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

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

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

      \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
    9. Step-by-step derivation
      1. add-sqr-sqrt1.6%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{1 + {\tan x}^{2}}} \cdot \sqrt{\frac{1}{1 + {\tan x}^{2}}}} \]
      2. sqrt-unprod1.6%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{1 + {\tan x}^{2}} \cdot \frac{1}{1 + {\tan x}^{2}}}} \]
      3. frac-2neg1.6%

        \[\leadsto \sqrt{\color{blue}{\frac{-1}{-\left(1 + {\tan x}^{2}\right)}} \cdot \frac{1}{1 + {\tan x}^{2}}} \]
      4. metadata-eval1.6%

        \[\leadsto \sqrt{\frac{\color{blue}{-1}}{-\left(1 + {\tan x}^{2}\right)} \cdot \frac{1}{1 + {\tan x}^{2}}} \]
      5. associate-*l/1.6%

        \[\leadsto \sqrt{\color{blue}{\frac{-1 \cdot \frac{1}{1 + {\tan x}^{2}}}{-\left(1 + {\tan x}^{2}\right)}}} \]
    10. Applied egg-rr17.3%

      \[\leadsto \color{blue}{-1 \cdot \frac{1}{1 + {\tan x}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/17.3%

        \[\leadsto \color{blue}{\frac{-1 \cdot 1}{1 + {\tan x}^{2}}} \]
      2. metadata-eval17.3%

        \[\leadsto \frac{\color{blue}{-1}}{1 + {\tan x}^{2}} \]
    12. Simplified17.3%

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

    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. sub-neg99.6%

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

        \[\leadsto \frac{\color{blue}{\left(-\tan x \cdot \tan x\right) + 1}}{1 + \tan x \cdot \tan x} \]
      3. distribute-rgt-neg-in99.6%

        \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
      4. fma-def99.6%

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

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
    4. Step-by-step derivation
      1. add-log-exp99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
      2. *-un-lft-identity99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
      3. log-prod99.6%

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

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
      5. add-log-exp99.6%

        \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
      6. pow299.6%

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

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
    6. Step-by-step derivation
      1. +-lft-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 69.8%

      \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification55.9%

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

Alternative 5: 99.5% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\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. sub-neg99.5%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    4. fma-def99.5%

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

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. add-log-exp98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    5. add-log-exp99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
    6. pow299.5%

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

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
  6. Step-by-step derivation
    1. +-lft-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. Step-by-step derivation
    1. fma-udef99.5%

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

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

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

      \[\leadsto \frac{\color{blue}{1 - \tan x \cdot \tan x}}{1 + {\tan x}^{2}} \]
    5. pow299.5%

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

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

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

Alternative 6: 58.8% accurate, 2.0× speedup?

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

\\
\frac{1}{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. sub-neg99.5%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    4. fma-def99.5%

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

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. add-log-exp98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    5. add-log-exp99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
    6. pow299.5%

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

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
  6. Step-by-step derivation
    1. +-lft-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 51.7%

    \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
  9. Step-by-step derivation
    1. +-commutative51.7%

      \[\leadsto \frac{1}{\color{blue}{{\tan x}^{2} + 1}} \]
    2. pow251.7%

      \[\leadsto \frac{1}{\color{blue}{\tan x \cdot \tan x} + 1} \]
    3. fma-def51.7%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    4. add-sqr-sqrt25.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{\tan x} \cdot \sqrt{\tan x}}, 1\right)} \]
    5. sqrt-prod53.4%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{\tan x \cdot \tan x}}, 1\right)} \]
    6. sqr-neg53.4%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \sqrt{\color{blue}{\left(-\tan x\right) \cdot \left(-\tan x\right)}}, 1\right)} \]
    7. sqrt-unprod27.9%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{-\tan x} \cdot \sqrt{-\tan x}}, 1\right)} \]
    8. add-sqr-sqrt55.2%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{-\tan x}, 1\right)} \]
    9. fma-udef55.2%

      \[\leadsto \frac{1}{\color{blue}{\tan x \cdot \left(-\tan x\right) + 1}} \]
    10. distribute-rgt-neg-in55.2%

      \[\leadsto \frac{1}{\color{blue}{\left(-\tan x \cdot \tan x\right)} + 1} \]
    11. pow255.2%

      \[\leadsto \frac{1}{\left(-\color{blue}{{\tan x}^{2}}\right) + 1} \]
    12. +-commutative55.2%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-{\tan x}^{2}\right)}} \]
    13. sub-neg55.2%

      \[\leadsto \frac{1}{\color{blue}{1 - {\tan x}^{2}}} \]
  10. Applied egg-rr55.2%

    \[\leadsto \frac{1}{\color{blue}{1 - {\tan x}^{2}}} \]
  11. Final simplification55.2%

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

Alternative 7: 59.5% accurate, 2.0× speedup?

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

\\
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. frac-2neg99.5%

      \[\leadsto \color{blue}{\frac{-\left(1 - \tan x \cdot \tan x\right)}{-\left(1 + \tan x \cdot \tan x\right)}} \]
    2. div-inv99.4%

      \[\leadsto \color{blue}{\left(-\left(1 - \tan x \cdot \tan x\right)\right) \cdot \frac{1}{-\left(1 + \tan x \cdot \tan x\right)}} \]
    3. pow299.4%

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

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{-\color{blue}{\left(\tan x \cdot \tan x + 1\right)}} \]
    5. distribute-neg-in99.4%

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\color{blue}{\left(-\tan x \cdot \tan x\right) + \left(-1\right)}} \]
    6. metadata-eval99.4%

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\left(-\tan x \cdot \tan x\right) + \color{blue}{-1}} \]
    7. neg-mul-199.4%

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\color{blue}{-1 \cdot \left(\tan x \cdot \tan x\right)} + -1} \]
    8. fma-def99.4%

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(-1, \tan x \cdot \tan x, -1\right)}} \]
    9. pow299.4%

      \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\mathsf{fma}\left(-1, \color{blue}{{\tan x}^{2}}, -1\right)} \]
  3. Applied egg-rr99.4%

    \[\leadsto \color{blue}{\left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \frac{1}{\mathsf{fma}\left(-1, {\tan x}^{2}, -1\right)}} \]
  4. Taylor expanded in x around 0 55.8%

    \[\leadsto \left(-\left(1 - {\tan x}^{2}\right)\right) \cdot \color{blue}{-1} \]
  5. Final simplification55.8%

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

Alternative 8: 55.3% 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. sub-neg99.5%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    4. fma-def99.5%

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

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. add-log-exp98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval98.7%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    5. add-log-exp99.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(0 + \color{blue}{\tan x \cdot \tan x}\right)} \]
    6. pow299.5%

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

    \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(0 + {\tan x}^{2}\right)}} \]
  6. Step-by-step derivation
    1. +-lft-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 51.3%

    \[\leadsto \color{blue}{1} \]
  9. Final simplification51.3%

    \[\leadsto 1 \]

Reproduce

?
herbie shell --seed 2023322 
(FPCore (x)
  :name "Trigonometry B"
  :precision binary64
  (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))