Trigonometry B

Percentage Accurate: 99.5% → 99.5%
Time: 12.7s
Alternatives: 7
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 7 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. sub-neg99.4%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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: 60.2% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\tan x \cdot \tan x \leq 1:\\ \;\;\;\;{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{-2}\\ \mathbf{else}:\\ \;\;\;\;e^{\log 2 - {x}^{2}} + -1\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (* (tan x) (tan x)) 1.0)
   (pow (hypot 1.0 (tan x)) -2.0)
   (+ (exp (- (log 2.0) (pow x 2.0))) -1.0)))
double code(double x) {
	double tmp;
	if ((tan(x) * tan(x)) <= 1.0) {
		tmp = pow(hypot(1.0, tan(x)), -2.0);
	} else {
		tmp = exp((log(2.0) - pow(x, 2.0))) + -1.0;
	}
	return tmp;
}
public static double code(double x) {
	double tmp;
	if ((Math.tan(x) * Math.tan(x)) <= 1.0) {
		tmp = Math.pow(Math.hypot(1.0, Math.tan(x)), -2.0);
	} else {
		tmp = Math.exp((Math.log(2.0) - Math.pow(x, 2.0))) + -1.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if (math.tan(x) * math.tan(x)) <= 1.0:
		tmp = math.pow(math.hypot(1.0, math.tan(x)), -2.0)
	else:
		tmp = math.exp((math.log(2.0) - math.pow(x, 2.0))) + -1.0
	return tmp
function code(x)
	tmp = 0.0
	if (Float64(tan(x) * tan(x)) <= 1.0)
		tmp = hypot(1.0, tan(x)) ^ -2.0;
	else
		tmp = Float64(exp(Float64(log(2.0) - (x ^ 2.0))) + -1.0);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if ((tan(x) * tan(x)) <= 1.0)
		tmp = hypot(1.0, tan(x)) ^ -2.0;
	else
		tmp = exp((log(2.0) - (x ^ 2.0))) + -1.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision], 1.0], N[Power[N[Sqrt[1.0 ^ 2 + N[Tan[x], $MachinePrecision] ^ 2], $MachinePrecision], -2.0], $MachinePrecision], N[(N[Exp[N[(N[Log[2.0], $MachinePrecision] - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + -1.0), $MachinePrecision]]
\begin{array}{l}

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

\mathbf{else}:\\
\;\;\;\;e^{\log 2 - {x}^{2}} + -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. 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 70.6%

      \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
    9. Step-by-step derivation
      1. expm1-log1p-u70.6%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + {\tan x}^{2}}\right)\right)} \]
      2. expm1-udef70.6%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + {\tan x}^{2}}\right)} - 1} \]
      3. pow170.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{{\left(1 + {\tan x}^{2}\right)}^{1}}}\right)} - 1 \]
      4. metadata-eval70.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{{\left(1 + {\tan x}^{2}\right)}^{\color{blue}{\left(\frac{2}{2}\right)}}}\right)} - 1 \]
      5. sqrt-pow270.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{{\left(\sqrt{1 + {\tan x}^{2}}\right)}^{2}}}\right)} - 1 \]
      6. metadata-eval70.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{{\left(\sqrt{\color{blue}{1 \cdot 1} + {\tan x}^{2}}\right)}^{2}}\right)} - 1 \]
      7. unpow270.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{{\left(\sqrt{1 \cdot 1 + \color{blue}{\tan x \cdot \tan x}}\right)}^{2}}\right)} - 1 \]
      8. hypot-udef70.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1}{{\color{blue}{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}}^{2}}\right)} - 1 \]
      9. pow-flip70.6%

        \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{\left(-2\right)}}\right)} - 1 \]
      10. metadata-eval70.6%

        \[\leadsto e^{\mathsf{log1p}\left({\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{\color{blue}{-2}}\right)} - 1 \]
    10. Applied egg-rr70.6%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left({\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{-2}\right)} - 1} \]
    11. Step-by-step derivation
      1. expm1-def70.6%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{-2}\right)\right)} \]
      2. expm1-log1p70.6%

        \[\leadsto \color{blue}{{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{-2}} \]
    12. Simplified70.6%

      \[\leadsto \color{blue}{{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{-2}} \]

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

    1. Initial program 98.9%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. expm1-log1p-u98.9%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)\right)} \]
      2. expm1-udef99.1%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\right)} - 1} \]
      3. pow299.1%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x}\right)} - 1 \]
      4. add-sqr-sqrt98.6%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1 - {\tan x}^{2}}{\color{blue}{\sqrt{1 + \tan x \cdot \tan x} \cdot \sqrt{1 + \tan x \cdot \tan x}}}\right)} - 1 \]
      5. pow298.5%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1 - {\tan x}^{2}}{\color{blue}{{\left(\sqrt{1 + \tan x \cdot \tan x}\right)}^{2}}}\right)} - 1 \]
      6. hypot-1-def98.5%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{1 - {\tan x}^{2}}{{\color{blue}{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}}^{2}}\right)} - 1 \]
    3. Applied egg-rr98.5%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1 - {\tan x}^{2}}{{\left(\mathsf{hypot}\left(1, \tan x\right)\right)}^{2}}\right)} - 1} \]
    4. Taylor expanded in x around 0 21.3%

      \[\leadsto e^{\color{blue}{\log 2 + -1 \cdot {x}^{2}}} - 1 \]
    5. Step-by-step derivation
      1. metadata-eval21.3%

        \[\leadsto e^{\log \color{blue}{\left(1 + 1\right)} + -1 \cdot {x}^{2}} - 1 \]
      2. metadata-eval21.3%

        \[\leadsto e^{\log \left(1 + \color{blue}{{1}^{2}}\right) + -1 \cdot {x}^{2}} - 1 \]
      3. *-inverses21.3%

        \[\leadsto e^{\log \left(1 + {\color{blue}{\left(\frac{\mathsf{hypot}\left(1, \tan x\right)}{\mathsf{hypot}\left(1, \tan x\right)}\right)}}^{2}\right) + -1 \cdot {x}^{2}} - 1 \]
      4. log1p-def21.3%

        \[\leadsto e^{\color{blue}{\mathsf{log1p}\left({\left(\frac{\mathsf{hypot}\left(1, \tan x\right)}{\mathsf{hypot}\left(1, \tan x\right)}\right)}^{2}\right)} + -1 \cdot {x}^{2}} - 1 \]
      5. mul-1-neg21.3%

        \[\leadsto e^{\mathsf{log1p}\left({\left(\frac{\mathsf{hypot}\left(1, \tan x\right)}{\mathsf{hypot}\left(1, \tan x\right)}\right)}^{2}\right) + \color{blue}{\left(-{x}^{2}\right)}} - 1 \]
      6. unsub-neg21.3%

        \[\leadsto e^{\color{blue}{\mathsf{log1p}\left({\left(\frac{\mathsf{hypot}\left(1, \tan x\right)}{\mathsf{hypot}\left(1, \tan x\right)}\right)}^{2}\right) - {x}^{2}}} - 1 \]
      7. log1p-def21.3%

        \[\leadsto e^{\color{blue}{\log \left(1 + {\left(\frac{\mathsf{hypot}\left(1, \tan x\right)}{\mathsf{hypot}\left(1, \tan x\right)}\right)}^{2}\right)} - {x}^{2}} - 1 \]
      8. *-inverses21.3%

        \[\leadsto e^{\log \left(1 + {\color{blue}{1}}^{2}\right) - {x}^{2}} - 1 \]
      9. metadata-eval21.3%

        \[\leadsto e^{\log \left(1 + \color{blue}{1}\right) - {x}^{2}} - 1 \]
      10. metadata-eval21.3%

        \[\leadsto e^{\log \color{blue}{2} - {x}^{2}} - 1 \]
    6. Simplified21.3%

      \[\leadsto e^{\color{blue}{\log 2 - {x}^{2}}} - 1 \]
  3. Recombined 2 regimes into one program.
  4. Final simplification59.0%

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

Alternative 3: 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. +-commutative99.4%

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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 4: 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. +-commutative99.4%

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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. Step-by-step derivation
    1. fma-udef99.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    2. pow299.4%

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{{\tan x}^{2}} + 1} \]
  9. Applied egg-rr99.4%

    \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{{\tan x}^{2} + 1}} \]
  10. Final simplification99.4%

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

Alternative 5: 55.2% 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. sub-neg99.4%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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 54.4%

    \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
  9. Final simplification54.4%

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

Alternative 6: 58.5% 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. sub-neg99.4%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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 54.4%

    \[\leadsto \frac{\color{blue}{1}}{1 + {\tan x}^{2}} \]
  9. Step-by-step derivation
    1. +-commutative54.4%

      \[\leadsto \frac{1}{\color{blue}{{\tan x}^{2} + 1}} \]
    2. unpow254.4%

      \[\leadsto \frac{1}{\color{blue}{\tan x \cdot \tan x} + 1} \]
    3. fma-def54.4%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
    4. add-sqr-sqrt28.8%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{\tan x} \cdot \sqrt{\tan x}}, 1\right)} \]
    5. sqrt-prod55.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{\tan x \cdot \tan x}}, 1\right)} \]
    6. sqr-neg55.5%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \sqrt{\color{blue}{\left(-\tan x\right) \cdot \left(-\tan x\right)}}, 1\right)} \]
    7. sqrt-unprod26.7%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{\sqrt{-\tan x} \cdot \sqrt{-\tan x}}, 1\right)} \]
    8. add-sqr-sqrt57.3%

      \[\leadsto \frac{1}{\mathsf{fma}\left(\tan x, \color{blue}{-\tan x}, 1\right)} \]
    9. fma-udef57.3%

      \[\leadsto \frac{1}{\color{blue}{\tan x \cdot \left(-\tan x\right) + 1}} \]
    10. distribute-rgt-neg-in57.3%

      \[\leadsto \frac{1}{\color{blue}{\left(-\tan x \cdot \tan x\right)} + 1} \]
    11. unpow257.3%

      \[\leadsto \frac{1}{\left(-\color{blue}{{\tan x}^{2}}\right) + 1} \]
    12. +-commutative57.3%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-{\tan x}^{2}\right)}} \]
    13. sub-neg57.3%

      \[\leadsto \frac{1}{\color{blue}{1 - {\tan x}^{2}}} \]
  10. Applied egg-rr57.3%

    \[\leadsto \frac{1}{\color{blue}{1 - {\tan x}^{2}}} \]
  11. Final simplification57.3%

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

Alternative 7: 54.8% 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 99.4%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. sub-neg99.4%

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

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

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(-\tan x\right)} + 1}{1 + \tan x \cdot \tan x} \]
    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-exp97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\log \left(e^{\tan x \cdot \tan x}\right)}} \]
    2. *-un-lft-identity97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \log \color{blue}{\left(1 \cdot e^{\tan x \cdot \tan x}\right)}} \]
    3. log-prod97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \color{blue}{\left(\log 1 + \log \left(e^{\tan x \cdot \tan x}\right)\right)}} \]
    4. metadata-eval97.9%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \left(\color{blue}{0} + \log \left(e^{\tan x \cdot \tan x}\right)\right)} \]
    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 54.0%

    \[\leadsto \color{blue}{1} \]
  9. Final simplification54.0%

    \[\leadsto 1 \]

Reproduce

?
herbie shell --seed 2023334 
(FPCore (x)
  :name "Trigonometry B"
  :precision binary64
  (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))