Diagrams.TwoD.Arc:arcBetween from diagrams-lib-1.3.0.3

Percentage Accurate: 50.9% → 81.1%
Time: 6.8s
Alternatives: 6
Speedup: 1.2×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(y \cdot 4\right) \cdot y\\ \frac{x \cdot x - t\_0}{x \cdot x + t\_0} \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (* (* y 4.0) y))) (/ (- (* x x) t_0) (+ (* x x) t_0))))
double code(double x, double y) {
	double t_0 = (y * 4.0) * y;
	return ((x * x) - t_0) / ((x * x) + t_0);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    t_0 = (y * 4.0d0) * y
    code = ((x * x) - t_0) / ((x * x) + t_0)
end function
public static double code(double x, double y) {
	double t_0 = (y * 4.0) * y;
	return ((x * x) - t_0) / ((x * x) + t_0);
}
def code(x, y):
	t_0 = (y * 4.0) * y
	return ((x * x) - t_0) / ((x * x) + t_0)
function code(x, y)
	t_0 = Float64(Float64(y * 4.0) * y)
	return Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0))
end
function tmp = code(x, y)
	t_0 = (y * 4.0) * y;
	tmp = ((x * x) - t_0) / ((x * x) + t_0);
end
code[x_, y_] := Block[{t$95$0 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(y \cdot 4\right) \cdot y\\
\frac{x \cdot x - t\_0}{x \cdot x + 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 6 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: 50.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(y \cdot 4\right) \cdot y\\ \frac{x \cdot x - t\_0}{x \cdot x + t\_0} \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (* (* y 4.0) y))) (/ (- (* x x) t_0) (+ (* x x) t_0))))
double code(double x, double y) {
	double t_0 = (y * 4.0) * y;
	return ((x * x) - t_0) / ((x * x) + t_0);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    t_0 = (y * 4.0d0) * y
    code = ((x * x) - t_0) / ((x * x) + t_0)
end function
public static double code(double x, double y) {
	double t_0 = (y * 4.0) * y;
	return ((x * x) - t_0) / ((x * x) + t_0);
}
def code(x, y):
	t_0 = (y * 4.0) * y
	return ((x * x) - t_0) / ((x * x) + t_0)
function code(x, y)
	t_0 = Float64(Float64(y * 4.0) * y)
	return Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0))
end
function tmp = code(x, y)
	t_0 = (y * 4.0) * y;
	tmp = ((x * x) - t_0) / ((x * x) + t_0);
end
code[x_, y_] := Block[{t$95$0 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(y \cdot 4\right) \cdot y\\
\frac{x \cdot x - t\_0}{x \cdot x + t\_0}
\end{array}
\end{array}

Alternative 1: 81.1% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \cdot x \leq 2 \cdot 10^{-142}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)\\ \mathbf{elif}\;x \cdot x \leq 5 \cdot 10^{+196}:\\ \;\;\;\;\frac{\mathsf{fma}\left(x, x, \left(y \cdot y\right) \cdot -4\right)}{\mathsf{fma}\left(y, y \cdot 4, x \cdot x\right)}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= (* x x) 2e-142)
   (fma (/ (* x 0.5) y) (/ x y) -1.0)
   (if (<= (* x x) 5e+196)
     (/ (fma x x (* (* y y) -4.0)) (fma y (* y 4.0) (* x x)))
     (fma (/ y x) (/ (* y -8.0) x) 1.0))))
double code(double x, double y) {
	double tmp;
	if ((x * x) <= 2e-142) {
		tmp = fma(((x * 0.5) / y), (x / y), -1.0);
	} else if ((x * x) <= 5e+196) {
		tmp = fma(x, x, ((y * y) * -4.0)) / fma(y, (y * 4.0), (x * x));
	} else {
		tmp = fma((y / x), ((y * -8.0) / x), 1.0);
	}
	return tmp;
}
function code(x, y)
	tmp = 0.0
	if (Float64(x * x) <= 2e-142)
		tmp = fma(Float64(Float64(x * 0.5) / y), Float64(x / y), -1.0);
	elseif (Float64(x * x) <= 5e+196)
		tmp = Float64(fma(x, x, Float64(Float64(y * y) * -4.0)) / fma(y, Float64(y * 4.0), Float64(x * x)));
	else
		tmp = fma(Float64(y / x), Float64(Float64(y * -8.0) / x), 1.0);
	end
	return tmp
end
code[x_, y_] := If[LessEqual[N[(x * x), $MachinePrecision], 2e-142], N[(N[(N[(x * 0.5), $MachinePrecision] / y), $MachinePrecision] * N[(x / y), $MachinePrecision] + -1.0), $MachinePrecision], If[LessEqual[N[(x * x), $MachinePrecision], 5e+196], N[(N[(x * x + N[(N[(y * y), $MachinePrecision] * -4.0), $MachinePrecision]), $MachinePrecision] / N[(y * N[(y * 4.0), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(y / x), $MachinePrecision] * N[(N[(y * -8.0), $MachinePrecision] / x), $MachinePrecision] + 1.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \cdot x \leq 2 \cdot 10^{-142}:\\
\;\;\;\;\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)\\

\mathbf{elif}\;x \cdot x \leq 5 \cdot 10^{+196}:\\
\;\;\;\;\frac{\mathsf{fma}\left(x, x, \left(y \cdot y\right) \cdot -4\right)}{\mathsf{fma}\left(y, y \cdot 4, x \cdot x\right)}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 x x) < 2.0000000000000001e-142

    1. Initial program 56.2%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} - 1} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right)} \]
      2. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \frac{\color{blue}{x \cdot x}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right) \]
      3. associate-/l*N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \frac{x}{{y}^{2}}\right)} + \left(\mathsf{neg}\left(1\right)\right) \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot x\right) \cdot \frac{x}{{y}^{2}}} + \left(\mathsf{neg}\left(1\right)\right) \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot x, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      7. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      8. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \color{blue}{\frac{x}{{y}^{2}}}, \mathsf{neg}\left(1\right)\right) \]
      9. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      10. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      11. metadata-eval70.4

        \[\leadsto \mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, \color{blue}{-1}\right) \]
    5. Simplified70.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(x \cdot \frac{1}{2}\right)} \cdot \frac{x}{y \cdot y} + -1 \]
      2. lift-*.f64N/A

        \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \frac{x}{\color{blue}{y \cdot y}} + -1 \]
      3. lift-/.f64N/A

        \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \color{blue}{\frac{x}{y \cdot y}} + -1 \]
      4. lift-/.f64N/A

        \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \color{blue}{\frac{x}{y \cdot y}} + -1 \]
      5. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\left(x \cdot \frac{1}{2}\right) \cdot x}{y \cdot y}} + -1 \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(x \cdot \frac{1}{2}\right) \cdot x}{\color{blue}{y \cdot y}} + -1 \]
      7. times-fracN/A

        \[\leadsto \color{blue}{\frac{x \cdot \frac{1}{2}}{y} \cdot \frac{x}{y}} + -1 \]
      8. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{x \cdot \frac{1}{2}}{y}, \frac{x}{y}, -1\right)} \]
      9. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{x \cdot \frac{1}{2}}{y}}, \frac{x}{y}, -1\right) \]
      10. lower-/.f6483.0

        \[\leadsto \mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \color{blue}{\frac{x}{y}}, -1\right) \]
    7. Applied egg-rr83.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)} \]

    if 2.0000000000000001e-142 < (*.f64 x x) < 4.9999999999999998e196

    1. Initial program 80.0%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{x \cdot x} - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{x \cdot x - \color{blue}{\left(y \cdot 4\right)} \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
      3. lift-*.f64N/A

        \[\leadsto \frac{x \cdot x - \color{blue}{\left(y \cdot 4\right) \cdot y}}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
      4. lift-*.f64N/A

        \[\leadsto \frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{\color{blue}{x \cdot x} + \left(y \cdot 4\right) \cdot y} \]
      5. lift-*.f64N/A

        \[\leadsto \frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \color{blue}{\left(y \cdot 4\right)} \cdot y} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \color{blue}{\left(y \cdot 4\right) \cdot y}} \]
      7. lift-+.f64N/A

        \[\leadsto \frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{\color{blue}{x \cdot x + \left(y \cdot 4\right) \cdot y}} \]
      8. lift--.f64N/A

        \[\leadsto \frac{\color{blue}{x \cdot x - \left(y \cdot 4\right) \cdot y}}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
      9. lift-/.f6480.0

        \[\leadsto \color{blue}{\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y}} \]
    4. Applied egg-rr80.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(x, x, \left(y \cdot y\right) \cdot -4\right)}{\mathsf{fma}\left(y, y \cdot 4, x \cdot x\right)}} \]

    if 4.9999999999999998e196 < (*.f64 x x)

    1. Initial program 17.4%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\left(1 + -4 \cdot \frac{{y}^{2}}{{x}^{2}}\right) - 4 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
    4. Step-by-step derivation
      1. associate--l+N/A

        \[\leadsto \color{blue}{1 + \left(-4 \cdot \frac{{y}^{2}}{{x}^{2}} - 4 \cdot \frac{{y}^{2}}{{x}^{2}}\right)} \]
      2. distribute-rgt-out--N/A

        \[\leadsto 1 + \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot \left(-4 - 4\right)} \]
      3. metadata-evalN/A

        \[\leadsto 1 + \frac{{y}^{2}}{{x}^{2}} \cdot \color{blue}{-8} \]
      4. *-commutativeN/A

        \[\leadsto 1 + \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
      5. +-commutativeN/A

        \[\leadsto \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}} + 1} \]
      6. *-commutativeN/A

        \[\leadsto \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot -8} + 1 \]
      7. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{{y}^{2} \cdot -8}{{x}^{2}}} + 1 \]
      8. associate-*r/N/A

        \[\leadsto \color{blue}{{y}^{2} \cdot \frac{-8}{{x}^{2}}} + 1 \]
      9. metadata-evalN/A

        \[\leadsto {y}^{2} \cdot \frac{\color{blue}{\mathsf{neg}\left(8\right)}}{{x}^{2}} + 1 \]
      10. distribute-neg-fracN/A

        \[\leadsto {y}^{2} \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{8}{{x}^{2}}\right)\right)} + 1 \]
      11. metadata-evalN/A

        \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\frac{\color{blue}{8 \cdot 1}}{{x}^{2}}\right)\right) + 1 \]
      12. associate-*r/N/A

        \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\color{blue}{8 \cdot \frac{1}{{x}^{2}}}\right)\right) + 1 \]
      13. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({y}^{2}, \mathsf{neg}\left(8 \cdot \frac{1}{{x}^{2}}\right), 1\right)} \]
    5. Simplified68.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(y \cdot y, \frac{-8}{x \cdot x}, 1\right)} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \frac{-8}{x \cdot x} + 1 \]
      2. lift-*.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \frac{-8}{\color{blue}{x \cdot x}} + 1 \]
      3. lift-/.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
      4. lift-/.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
      5. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\left(y \cdot y\right) \cdot -8}{x \cdot x}} + 1 \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{\left(y \cdot y\right)} \cdot -8}{x \cdot x} + 1 \]
      7. associate-*l*N/A

        \[\leadsto \frac{\color{blue}{y \cdot \left(y \cdot -8\right)}}{x \cdot x} + 1 \]
      8. lift-*.f64N/A

        \[\leadsto \frac{y \cdot \left(y \cdot -8\right)}{\color{blue}{x \cdot x}} + 1 \]
      9. times-fracN/A

        \[\leadsto \color{blue}{\frac{y}{x} \cdot \frac{y \cdot -8}{x}} + 1 \]
      10. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]
      11. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{x}}, \frac{y \cdot -8}{x}, 1\right) \]
      12. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \color{blue}{\frac{y \cdot -8}{x}}, 1\right) \]
      13. lower-*.f6479.8

        \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \frac{\color{blue}{y \cdot -8}}{x}, 1\right) \]
    7. Applied egg-rr79.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 2: 76.5% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y \cdot \left(y \cdot 4\right)\\ \mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -0.5:\\ \;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (* y (* y 4.0))))
   (if (<= (/ (- (* x x) t_0) (+ (* x x) t_0)) -0.5)
     (fma (* x 0.5) (/ x (* y y)) -1.0)
     (fma (/ y x) (/ (* y -8.0) x) 1.0))))
double code(double x, double y) {
	double t_0 = y * (y * 4.0);
	double tmp;
	if ((((x * x) - t_0) / ((x * x) + t_0)) <= -0.5) {
		tmp = fma((x * 0.5), (x / (y * y)), -1.0);
	} else {
		tmp = fma((y / x), ((y * -8.0) / x), 1.0);
	}
	return tmp;
}
function code(x, y)
	t_0 = Float64(y * Float64(y * 4.0))
	tmp = 0.0
	if (Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)) <= -0.5)
		tmp = fma(Float64(x * 0.5), Float64(x / Float64(y * y)), -1.0);
	else
		tmp = fma(Float64(y / x), Float64(Float64(y * -8.0) / x), 1.0);
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision], -0.5], N[(N[(x * 0.5), $MachinePrecision] * N[(x / N[(y * y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], N[(N[(y / x), $MachinePrecision] * N[(N[(y * -8.0), $MachinePrecision] / x), $MachinePrecision] + 1.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y \cdot \left(y \cdot 4\right)\\
\mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -0.5:\\
\;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y))) < -0.5

    1. Initial program 100.0%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} - 1} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right)} \]
      2. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \frac{\color{blue}{x \cdot x}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right) \]
      3. associate-/l*N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \frac{x}{{y}^{2}}\right)} + \left(\mathsf{neg}\left(1\right)\right) \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot x\right) \cdot \frac{x}{{y}^{2}}} + \left(\mathsf{neg}\left(1\right)\right) \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot x, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      7. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      8. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \color{blue}{\frac{x}{{y}^{2}}}, \mathsf{neg}\left(1\right)\right) \]
      9. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      10. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      11. metadata-eval100.0

        \[\leadsto \mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, \color{blue}{-1}\right) \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)} \]

    if -0.5 < (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)))

    1. Initial program 32.6%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\left(1 + -4 \cdot \frac{{y}^{2}}{{x}^{2}}\right) - 4 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
    4. Step-by-step derivation
      1. associate--l+N/A

        \[\leadsto \color{blue}{1 + \left(-4 \cdot \frac{{y}^{2}}{{x}^{2}} - 4 \cdot \frac{{y}^{2}}{{x}^{2}}\right)} \]
      2. distribute-rgt-out--N/A

        \[\leadsto 1 + \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot \left(-4 - 4\right)} \]
      3. metadata-evalN/A

        \[\leadsto 1 + \frac{{y}^{2}}{{x}^{2}} \cdot \color{blue}{-8} \]
      4. *-commutativeN/A

        \[\leadsto 1 + \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
      5. +-commutativeN/A

        \[\leadsto \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}} + 1} \]
      6. *-commutativeN/A

        \[\leadsto \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot -8} + 1 \]
      7. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{{y}^{2} \cdot -8}{{x}^{2}}} + 1 \]
      8. associate-*r/N/A

        \[\leadsto \color{blue}{{y}^{2} \cdot \frac{-8}{{x}^{2}}} + 1 \]
      9. metadata-evalN/A

        \[\leadsto {y}^{2} \cdot \frac{\color{blue}{\mathsf{neg}\left(8\right)}}{{x}^{2}} + 1 \]
      10. distribute-neg-fracN/A

        \[\leadsto {y}^{2} \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{8}{{x}^{2}}\right)\right)} + 1 \]
      11. metadata-evalN/A

        \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\frac{\color{blue}{8 \cdot 1}}{{x}^{2}}\right)\right) + 1 \]
      12. associate-*r/N/A

        \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\color{blue}{8 \cdot \frac{1}{{x}^{2}}}\right)\right) + 1 \]
      13. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({y}^{2}, \mathsf{neg}\left(8 \cdot \frac{1}{{x}^{2}}\right), 1\right)} \]
    5. Simplified57.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(y \cdot y, \frac{-8}{x \cdot x}, 1\right)} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \frac{-8}{x \cdot x} + 1 \]
      2. lift-*.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \frac{-8}{\color{blue}{x \cdot x}} + 1 \]
      3. lift-/.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
      4. lift-/.f64N/A

        \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
      5. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\left(y \cdot y\right) \cdot -8}{x \cdot x}} + 1 \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{\left(y \cdot y\right)} \cdot -8}{x \cdot x} + 1 \]
      7. associate-*l*N/A

        \[\leadsto \frac{\color{blue}{y \cdot \left(y \cdot -8\right)}}{x \cdot x} + 1 \]
      8. lift-*.f64N/A

        \[\leadsto \frac{y \cdot \left(y \cdot -8\right)}{\color{blue}{x \cdot x}} + 1 \]
      9. times-fracN/A

        \[\leadsto \color{blue}{\frac{y}{x} \cdot \frac{y \cdot -8}{x}} + 1 \]
      10. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]
      11. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{x}}, \frac{y \cdot -8}{x}, 1\right) \]
      12. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \color{blue}{\frac{y \cdot -8}{x}}, 1\right) \]
      13. lower-*.f6467.9

        \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \frac{\color{blue}{y \cdot -8}}{x}, 1\right) \]
    7. Applied egg-rr67.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x \cdot x - y \cdot \left(y \cdot 4\right)}{x \cdot x + y \cdot \left(y \cdot 4\right)} \leq -0.5:\\ \;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 75.7% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y \cdot \left(y \cdot 4\right)\\ \mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -0.5:\\ \;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (* y (* y 4.0))))
   (if (<= (/ (- (* x x) t_0) (+ (* x x) t_0)) -0.5)
     (fma (* x 0.5) (/ x (* y y)) -1.0)
     1.0)))
double code(double x, double y) {
	double t_0 = y * (y * 4.0);
	double tmp;
	if ((((x * x) - t_0) / ((x * x) + t_0)) <= -0.5) {
		tmp = fma((x * 0.5), (x / (y * y)), -1.0);
	} else {
		tmp = 1.0;
	}
	return tmp;
}
function code(x, y)
	t_0 = Float64(y * Float64(y * 4.0))
	tmp = 0.0
	if (Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)) <= -0.5)
		tmp = fma(Float64(x * 0.5), Float64(x / Float64(y * y)), -1.0);
	else
		tmp = 1.0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision], -0.5], N[(N[(x * 0.5), $MachinePrecision] * N[(x / N[(y * y), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision], 1.0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y \cdot \left(y \cdot 4\right)\\
\mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -0.5:\\
\;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y))) < -0.5

    1. Initial program 100.0%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} - 1} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right)} \]
      2. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \frac{\color{blue}{x \cdot x}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right) \]
      3. associate-/l*N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \frac{x}{{y}^{2}}\right)} + \left(\mathsf{neg}\left(1\right)\right) \]
      4. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot x\right) \cdot \frac{x}{{y}^{2}}} + \left(\mathsf{neg}\left(1\right)\right) \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot x, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      7. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
      8. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \color{blue}{\frac{x}{{y}^{2}}}, \mathsf{neg}\left(1\right)\right) \]
      9. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      10. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
      11. metadata-eval100.0

        \[\leadsto \mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, \color{blue}{-1}\right) \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)} \]

    if -0.5 < (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)))

    1. Initial program 32.6%

      \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto \color{blue}{1} \]
    4. Step-by-step derivation
      1. Simplified66.6%

        \[\leadsto \color{blue}{1} \]
    5. Recombined 2 regimes into one program.
    6. Final simplification74.8%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x \cdot x - y \cdot \left(y \cdot 4\right)}{x \cdot x + y \cdot \left(y \cdot 4\right)} \leq -0.5:\\ \;\;\;\;\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
    7. Add Preprocessing

    Alternative 4: 75.6% accurate, 0.9× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := y \cdot \left(y \cdot 4\right)\\ \mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -2 \cdot 10^{-315}:\\ \;\;\;\;-1\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (let* ((t_0 (* y (* y 4.0))))
       (if (<= (/ (- (* x x) t_0) (+ (* x x) t_0)) -2e-315) -1.0 1.0)))
    double code(double x, double y) {
    	double t_0 = y * (y * 4.0);
    	double tmp;
    	if ((((x * x) - t_0) / ((x * x) + t_0)) <= -2e-315) {
    		tmp = -1.0;
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    real(8) function code(x, y)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8) :: t_0
        real(8) :: tmp
        t_0 = y * (y * 4.0d0)
        if ((((x * x) - t_0) / ((x * x) + t_0)) <= (-2d-315)) then
            tmp = -1.0d0
        else
            tmp = 1.0d0
        end if
        code = tmp
    end function
    
    public static double code(double x, double y) {
    	double t_0 = y * (y * 4.0);
    	double tmp;
    	if ((((x * x) - t_0) / ((x * x) + t_0)) <= -2e-315) {
    		tmp = -1.0;
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    def code(x, y):
    	t_0 = y * (y * 4.0)
    	tmp = 0
    	if (((x * x) - t_0) / ((x * x) + t_0)) <= -2e-315:
    		tmp = -1.0
    	else:
    		tmp = 1.0
    	return tmp
    
    function code(x, y)
    	t_0 = Float64(y * Float64(y * 4.0))
    	tmp = 0.0
    	if (Float64(Float64(Float64(x * x) - t_0) / Float64(Float64(x * x) + t_0)) <= -2e-315)
    		tmp = -1.0;
    	else
    		tmp = 1.0;
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y)
    	t_0 = y * (y * 4.0);
    	tmp = 0.0;
    	if ((((x * x) - t_0) / ((x * x) + t_0)) <= -2e-315)
    		tmp = -1.0;
    	else
    		tmp = 1.0;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_] := Block[{t$95$0 = N[(y * N[(y * 4.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(x * x), $MachinePrecision] - t$95$0), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision], -2e-315], -1.0, 1.0]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := y \cdot \left(y \cdot 4\right)\\
    \mathbf{if}\;\frac{x \cdot x - t\_0}{x \cdot x + t\_0} \leq -2 \cdot 10^{-315}:\\
    \;\;\;\;-1\\
    
    \mathbf{else}:\\
    \;\;\;\;1\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y))) < -2.0000000019e-315

      1. Initial program 100.0%

        \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{-1} \]
      4. Step-by-step derivation
        1. Simplified99.8%

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

        if -2.0000000019e-315 < (/.f64 (-.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)) (+.f64 (*.f64 x x) (*.f64 (*.f64 y #s(literal 4 binary64)) y)))

        1. Initial program 32.6%

          \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

          \[\leadsto \color{blue}{1} \]
        4. Step-by-step derivation
          1. Simplified66.6%

            \[\leadsto \color{blue}{1} \]
        5. Recombined 2 regimes into one program.
        6. Final simplification74.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x \cdot x - y \cdot \left(y \cdot 4\right)}{x \cdot x + y \cdot \left(y \cdot 4\right)} \leq -2 \cdot 10^{-315}:\\ \;\;\;\;-1\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
        7. Add Preprocessing

        Alternative 5: 64.1% accurate, 1.2× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq 1.2 \cdot 10^{-15}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)\\ \end{array} \end{array} \]
        (FPCore (x y)
         :precision binary64
         (if (<= y 1.2e-15)
           (fma (/ y x) (/ (* y -8.0) x) 1.0)
           (fma (/ (* x 0.5) y) (/ x y) -1.0)))
        double code(double x, double y) {
        	double tmp;
        	if (y <= 1.2e-15) {
        		tmp = fma((y / x), ((y * -8.0) / x), 1.0);
        	} else {
        		tmp = fma(((x * 0.5) / y), (x / y), -1.0);
        	}
        	return tmp;
        }
        
        function code(x, y)
        	tmp = 0.0
        	if (y <= 1.2e-15)
        		tmp = fma(Float64(y / x), Float64(Float64(y * -8.0) / x), 1.0);
        	else
        		tmp = fma(Float64(Float64(x * 0.5) / y), Float64(x / y), -1.0);
        	end
        	return tmp
        end
        
        code[x_, y_] := If[LessEqual[y, 1.2e-15], N[(N[(y / x), $MachinePrecision] * N[(N[(y * -8.0), $MachinePrecision] / x), $MachinePrecision] + 1.0), $MachinePrecision], N[(N[(N[(x * 0.5), $MachinePrecision] / y), $MachinePrecision] * N[(x / y), $MachinePrecision] + -1.0), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;y \leq 1.2 \cdot 10^{-15}:\\
        \;\;\;\;\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if y < 1.19999999999999997e-15

          1. Initial program 50.8%

            \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
          2. Add Preprocessing
          3. Taylor expanded in x around inf

            \[\leadsto \color{blue}{\left(1 + -4 \cdot \frac{{y}^{2}}{{x}^{2}}\right) - 4 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
          4. Step-by-step derivation
            1. associate--l+N/A

              \[\leadsto \color{blue}{1 + \left(-4 \cdot \frac{{y}^{2}}{{x}^{2}} - 4 \cdot \frac{{y}^{2}}{{x}^{2}}\right)} \]
            2. distribute-rgt-out--N/A

              \[\leadsto 1 + \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot \left(-4 - 4\right)} \]
            3. metadata-evalN/A

              \[\leadsto 1 + \frac{{y}^{2}}{{x}^{2}} \cdot \color{blue}{-8} \]
            4. *-commutativeN/A

              \[\leadsto 1 + \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}}} \]
            5. +-commutativeN/A

              \[\leadsto \color{blue}{-8 \cdot \frac{{y}^{2}}{{x}^{2}} + 1} \]
            6. *-commutativeN/A

              \[\leadsto \color{blue}{\frac{{y}^{2}}{{x}^{2}} \cdot -8} + 1 \]
            7. associate-*l/N/A

              \[\leadsto \color{blue}{\frac{{y}^{2} \cdot -8}{{x}^{2}}} + 1 \]
            8. associate-*r/N/A

              \[\leadsto \color{blue}{{y}^{2} \cdot \frac{-8}{{x}^{2}}} + 1 \]
            9. metadata-evalN/A

              \[\leadsto {y}^{2} \cdot \frac{\color{blue}{\mathsf{neg}\left(8\right)}}{{x}^{2}} + 1 \]
            10. distribute-neg-fracN/A

              \[\leadsto {y}^{2} \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{8}{{x}^{2}}\right)\right)} + 1 \]
            11. metadata-evalN/A

              \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\frac{\color{blue}{8 \cdot 1}}{{x}^{2}}\right)\right) + 1 \]
            12. associate-*r/N/A

              \[\leadsto {y}^{2} \cdot \left(\mathsf{neg}\left(\color{blue}{8 \cdot \frac{1}{{x}^{2}}}\right)\right) + 1 \]
            13. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left({y}^{2}, \mathsf{neg}\left(8 \cdot \frac{1}{{x}^{2}}\right), 1\right)} \]
          5. Simplified55.1%

            \[\leadsto \color{blue}{\mathsf{fma}\left(y \cdot y, \frac{-8}{x \cdot x}, 1\right)} \]
          6. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{\left(y \cdot y\right)} \cdot \frac{-8}{x \cdot x} + 1 \]
            2. lift-*.f64N/A

              \[\leadsto \left(y \cdot y\right) \cdot \frac{-8}{\color{blue}{x \cdot x}} + 1 \]
            3. lift-/.f64N/A

              \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
            4. lift-/.f64N/A

              \[\leadsto \left(y \cdot y\right) \cdot \color{blue}{\frac{-8}{x \cdot x}} + 1 \]
            5. associate-*r/N/A

              \[\leadsto \color{blue}{\frac{\left(y \cdot y\right) \cdot -8}{x \cdot x}} + 1 \]
            6. lift-*.f64N/A

              \[\leadsto \frac{\color{blue}{\left(y \cdot y\right)} \cdot -8}{x \cdot x} + 1 \]
            7. associate-*l*N/A

              \[\leadsto \frac{\color{blue}{y \cdot \left(y \cdot -8\right)}}{x \cdot x} + 1 \]
            8. lift-*.f64N/A

              \[\leadsto \frac{y \cdot \left(y \cdot -8\right)}{\color{blue}{x \cdot x}} + 1 \]
            9. times-fracN/A

              \[\leadsto \color{blue}{\frac{y}{x} \cdot \frac{y \cdot -8}{x}} + 1 \]
            10. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]
            11. lower-/.f64N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{x}}, \frac{y \cdot -8}{x}, 1\right) \]
            12. lower-/.f64N/A

              \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \color{blue}{\frac{y \cdot -8}{x}}, 1\right) \]
            13. lower-*.f6462.7

              \[\leadsto \mathsf{fma}\left(\frac{y}{x}, \frac{\color{blue}{y \cdot -8}}{x}, 1\right) \]
          7. Applied egg-rr62.7%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{x}, \frac{y \cdot -8}{x}, 1\right)} \]

          if 1.19999999999999997e-15 < y

          1. Initial program 44.8%

            \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} - 1} \]
          4. Step-by-step derivation
            1. sub-negN/A

              \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{{x}^{2}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right)} \]
            2. unpow2N/A

              \[\leadsto \frac{1}{2} \cdot \frac{\color{blue}{x \cdot x}}{{y}^{2}} + \left(\mathsf{neg}\left(1\right)\right) \]
            3. associate-/l*N/A

              \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \frac{x}{{y}^{2}}\right)} + \left(\mathsf{neg}\left(1\right)\right) \]
            4. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot x\right) \cdot \frac{x}{{y}^{2}}} + \left(\mathsf{neg}\left(1\right)\right) \]
            5. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot x, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right)} \]
            6. *-commutativeN/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
            7. lower-*.f64N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot \frac{1}{2}}, \frac{x}{{y}^{2}}, \mathsf{neg}\left(1\right)\right) \]
            8. lower-/.f64N/A

              \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \color{blue}{\frac{x}{{y}^{2}}}, \mathsf{neg}\left(1\right)\right) \]
            9. unpow2N/A

              \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
            10. lower-*.f64N/A

              \[\leadsto \mathsf{fma}\left(x \cdot \frac{1}{2}, \frac{x}{\color{blue}{y \cdot y}}, \mathsf{neg}\left(1\right)\right) \]
            11. metadata-eval79.9

              \[\leadsto \mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, \color{blue}{-1}\right) \]
          5. Simplified79.9%

            \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot 0.5, \frac{x}{y \cdot y}, -1\right)} \]
          6. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{\left(x \cdot \frac{1}{2}\right)} \cdot \frac{x}{y \cdot y} + -1 \]
            2. lift-*.f64N/A

              \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \frac{x}{\color{blue}{y \cdot y}} + -1 \]
            3. lift-/.f64N/A

              \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \color{blue}{\frac{x}{y \cdot y}} + -1 \]
            4. lift-/.f64N/A

              \[\leadsto \left(x \cdot \frac{1}{2}\right) \cdot \color{blue}{\frac{x}{y \cdot y}} + -1 \]
            5. associate-*r/N/A

              \[\leadsto \color{blue}{\frac{\left(x \cdot \frac{1}{2}\right) \cdot x}{y \cdot y}} + -1 \]
            6. lift-*.f64N/A

              \[\leadsto \frac{\left(x \cdot \frac{1}{2}\right) \cdot x}{\color{blue}{y \cdot y}} + -1 \]
            7. times-fracN/A

              \[\leadsto \color{blue}{\frac{x \cdot \frac{1}{2}}{y} \cdot \frac{x}{y}} + -1 \]
            8. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{x \cdot \frac{1}{2}}{y}, \frac{x}{y}, -1\right)} \]
            9. lower-/.f64N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{x \cdot \frac{1}{2}}{y}}, \frac{x}{y}, -1\right) \]
            10. lower-/.f6480.4

              \[\leadsto \mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \color{blue}{\frac{x}{y}}, -1\right) \]
          7. Applied egg-rr80.4%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{x \cdot 0.5}{y}, \frac{x}{y}, -1\right)} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 6: 50.3% accurate, 48.0× speedup?

        \[\begin{array}{l} \\ -1 \end{array} \]
        (FPCore (x y) :precision binary64 -1.0)
        double code(double x, double y) {
        	return -1.0;
        }
        
        real(8) function code(x, y)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            code = -1.0d0
        end function
        
        public static double code(double x, double y) {
        	return -1.0;
        }
        
        def code(x, y):
        	return -1.0
        
        function code(x, y)
        	return -1.0
        end
        
        function tmp = code(x, y)
        	tmp = -1.0;
        end
        
        code[x_, y_] := -1.0
        
        \begin{array}{l}
        
        \\
        -1
        \end{array}
        
        Derivation
        1. Initial program 49.2%

          \[\frac{x \cdot x - \left(y \cdot 4\right) \cdot y}{x \cdot x + \left(y \cdot 4\right) \cdot y} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{-1} \]
        4. Step-by-step derivation
          1. Simplified49.4%

            \[\leadsto \color{blue}{-1} \]
          2. Add Preprocessing

          Developer Target 1: 51.4% accurate, 0.2× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(y \cdot y\right) \cdot 4\\ t_1 := x \cdot x + t\_0\\ t_2 := \frac{t\_0}{t\_1}\\ t_3 := \left(y \cdot 4\right) \cdot y\\ \mathbf{if}\;\frac{x \cdot x - t\_3}{x \cdot x + t\_3} < 0.9743233849626781:\\ \;\;\;\;\frac{x \cdot x}{t\_1} - t\_2\\ \mathbf{else}:\\ \;\;\;\;{\left(\frac{x}{\sqrt{t\_1}}\right)}^{2} - t\_2\\ \end{array} \end{array} \]
          (FPCore (x y)
           :precision binary64
           (let* ((t_0 (* (* y y) 4.0))
                  (t_1 (+ (* x x) t_0))
                  (t_2 (/ t_0 t_1))
                  (t_3 (* (* y 4.0) y)))
             (if (< (/ (- (* x x) t_3) (+ (* x x) t_3)) 0.9743233849626781)
               (- (/ (* x x) t_1) t_2)
               (- (pow (/ x (sqrt t_1)) 2.0) t_2))))
          double code(double x, double y) {
          	double t_0 = (y * y) * 4.0;
          	double t_1 = (x * x) + t_0;
          	double t_2 = t_0 / t_1;
          	double t_3 = (y * 4.0) * y;
          	double tmp;
          	if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781) {
          		tmp = ((x * x) / t_1) - t_2;
          	} else {
          		tmp = pow((x / sqrt(t_1)), 2.0) - t_2;
          	}
          	return tmp;
          }
          
          real(8) function code(x, y)
              real(8), intent (in) :: x
              real(8), intent (in) :: y
              real(8) :: t_0
              real(8) :: t_1
              real(8) :: t_2
              real(8) :: t_3
              real(8) :: tmp
              t_0 = (y * y) * 4.0d0
              t_1 = (x * x) + t_0
              t_2 = t_0 / t_1
              t_3 = (y * 4.0d0) * y
              if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781d0) then
                  tmp = ((x * x) / t_1) - t_2
              else
                  tmp = ((x / sqrt(t_1)) ** 2.0d0) - t_2
              end if
              code = tmp
          end function
          
          public static double code(double x, double y) {
          	double t_0 = (y * y) * 4.0;
          	double t_1 = (x * x) + t_0;
          	double t_2 = t_0 / t_1;
          	double t_3 = (y * 4.0) * y;
          	double tmp;
          	if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781) {
          		tmp = ((x * x) / t_1) - t_2;
          	} else {
          		tmp = Math.pow((x / Math.sqrt(t_1)), 2.0) - t_2;
          	}
          	return tmp;
          }
          
          def code(x, y):
          	t_0 = (y * y) * 4.0
          	t_1 = (x * x) + t_0
          	t_2 = t_0 / t_1
          	t_3 = (y * 4.0) * y
          	tmp = 0
          	if (((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781:
          		tmp = ((x * x) / t_1) - t_2
          	else:
          		tmp = math.pow((x / math.sqrt(t_1)), 2.0) - t_2
          	return tmp
          
          function code(x, y)
          	t_0 = Float64(Float64(y * y) * 4.0)
          	t_1 = Float64(Float64(x * x) + t_0)
          	t_2 = Float64(t_0 / t_1)
          	t_3 = Float64(Float64(y * 4.0) * y)
          	tmp = 0.0
          	if (Float64(Float64(Float64(x * x) - t_3) / Float64(Float64(x * x) + t_3)) < 0.9743233849626781)
          		tmp = Float64(Float64(Float64(x * x) / t_1) - t_2);
          	else
          		tmp = Float64((Float64(x / sqrt(t_1)) ^ 2.0) - t_2);
          	end
          	return tmp
          end
          
          function tmp_2 = code(x, y)
          	t_0 = (y * y) * 4.0;
          	t_1 = (x * x) + t_0;
          	t_2 = t_0 / t_1;
          	t_3 = (y * 4.0) * y;
          	tmp = 0.0;
          	if ((((x * x) - t_3) / ((x * x) + t_3)) < 0.9743233849626781)
          		tmp = ((x * x) / t_1) - t_2;
          	else
          		tmp = ((x / sqrt(t_1)) ^ 2.0) - t_2;
          	end
          	tmp_2 = tmp;
          end
          
          code[x_, y_] := Block[{t$95$0 = N[(N[(y * y), $MachinePrecision] * 4.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(x * x), $MachinePrecision] + t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$0 / t$95$1), $MachinePrecision]}, Block[{t$95$3 = N[(N[(y * 4.0), $MachinePrecision] * y), $MachinePrecision]}, If[Less[N[(N[(N[(x * x), $MachinePrecision] - t$95$3), $MachinePrecision] / N[(N[(x * x), $MachinePrecision] + t$95$3), $MachinePrecision]), $MachinePrecision], 0.9743233849626781], N[(N[(N[(x * x), $MachinePrecision] / t$95$1), $MachinePrecision] - t$95$2), $MachinePrecision], N[(N[Power[N[(x / N[Sqrt[t$95$1], $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision] - t$95$2), $MachinePrecision]]]]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_0 := \left(y \cdot y\right) \cdot 4\\
          t_1 := x \cdot x + t\_0\\
          t_2 := \frac{t\_0}{t\_1}\\
          t_3 := \left(y \cdot 4\right) \cdot y\\
          \mathbf{if}\;\frac{x \cdot x - t\_3}{x \cdot x + t\_3} < 0.9743233849626781:\\
          \;\;\;\;\frac{x \cdot x}{t\_1} - t\_2\\
          
          \mathbf{else}:\\
          \;\;\;\;{\left(\frac{x}{\sqrt{t\_1}}\right)}^{2} - t\_2\\
          
          
          \end{array}
          \end{array}
          

          Reproduce

          ?
          herbie shell --seed 2024212 
          (FPCore (x y)
            :name "Diagrams.TwoD.Arc:arcBetween from diagrams-lib-1.3.0.3"
            :precision binary64
          
            :alt
            (! :herbie-platform default (if (< (/ (- (* x x) (* (* y 4) y)) (+ (* x x) (* (* y 4) y))) 9743233849626781/10000000000000000) (- (/ (* x x) (+ (* x x) (* (* y y) 4))) (/ (* (* y y) 4) (+ (* x x) (* (* y y) 4)))) (- (pow (/ x (sqrt (+ (* x x) (* (* y y) 4)))) 2) (/ (* (* y y) 4) (+ (* x x) (* (* y y) 4))))))
          
            (/ (- (* x x) (* (* y 4.0) y)) (+ (* x x) (* (* y 4.0) y))))