Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, A

Percentage Accurate: 100.0% → 100.0%
Time: 4.6s
Alternatives: 8
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \end{array} \]
(FPCore (x y)
 :precision binary64
 (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))
double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * (y - 1.0d0)) - (y * 0.5d0)) + 0.918938533204673d0
end function
public static double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
def code(x, y):
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673
function code(x, y)
	return Float64(Float64(Float64(x * Float64(y - 1.0)) - Float64(y * 0.5)) + 0.918938533204673)
end
function tmp = code(x, y)
	tmp = ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
end
code[x_, y_] := N[(N[(N[(x * N[(y - 1.0), $MachinePrecision]), $MachinePrecision] - N[(y * 0.5), $MachinePrecision]), $MachinePrecision] + 0.918938533204673), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673
\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: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \end{array} \]
(FPCore (x y)
 :precision binary64
 (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))
double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * (y - 1.0d0)) - (y * 0.5d0)) + 0.918938533204673d0
end function
public static double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
def code(x, y):
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673
function code(x, y)
	return Float64(Float64(Float64(x * Float64(y - 1.0)) - Float64(y * 0.5)) + 0.918938533204673)
end
function tmp = code(x, y)
	tmp = ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
end
code[x_, y_] := N[(N[(N[(x * N[(y - 1.0), $MachinePrecision]), $MachinePrecision] - N[(y * 0.5), $MachinePrecision]), $MachinePrecision] + 0.918938533204673), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673
\end{array}

Alternative 1: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot \left(y + -1\right) - y \cdot 0.5\right) + 0.918938533204673 \end{array} \]
(FPCore (x y)
 :precision binary64
 (+ (- (* x (+ y -1.0)) (* y 0.5)) 0.918938533204673))
double code(double x, double y) {
	return ((x * (y + -1.0)) - (y * 0.5)) + 0.918938533204673;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * (y + (-1.0d0))) - (y * 0.5d0)) + 0.918938533204673d0
end function
public static double code(double x, double y) {
	return ((x * (y + -1.0)) - (y * 0.5)) + 0.918938533204673;
}
def code(x, y):
	return ((x * (y + -1.0)) - (y * 0.5)) + 0.918938533204673
function code(x, y)
	return Float64(Float64(Float64(x * Float64(y + -1.0)) - Float64(y * 0.5)) + 0.918938533204673)
end
function tmp = code(x, y)
	tmp = ((x * (y + -1.0)) - (y * 0.5)) + 0.918938533204673;
end
code[x_, y_] := N[(N[(N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision] - N[(y * 0.5), $MachinePrecision]), $MachinePrecision] + 0.918938533204673), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \left(y + -1\right) - y \cdot 0.5\right) + 0.918938533204673
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
  2. Final simplification100.0%

    \[\leadsto \left(x \cdot \left(y + -1\right) - y \cdot 0.5\right) + 0.918938533204673 \]

Alternative 2: 73.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.918938533204673 + x \cdot y\\ \mathbf{if}\;x \leq -7.4 \cdot 10^{+264}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;x \leq -2.6 \cdot 10^{+20}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;x \leq -1 \cdot 10^{-13}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;x \leq 0.5:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 0.918938533204673 (* x y))))
   (if (<= x -7.4e+264)
     (- 0.918938533204673 x)
     (if (<= x -2.6e+20)
       t_0
       (if (<= x -1e-13)
         (- 0.918938533204673 x)
         (if (<= x 0.5) (- 0.918938533204673 (* y 0.5)) t_0))))))
double code(double x, double y) {
	double t_0 = 0.918938533204673 + (x * y);
	double tmp;
	if (x <= -7.4e+264) {
		tmp = 0.918938533204673 - x;
	} else if (x <= -2.6e+20) {
		tmp = t_0;
	} else if (x <= -1e-13) {
		tmp = 0.918938533204673 - x;
	} else if (x <= 0.5) {
		tmp = 0.918938533204673 - (y * 0.5);
	} else {
		tmp = t_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 = 0.918938533204673d0 + (x * y)
    if (x <= (-7.4d+264)) then
        tmp = 0.918938533204673d0 - x
    else if (x <= (-2.6d+20)) then
        tmp = t_0
    else if (x <= (-1d-13)) then
        tmp = 0.918938533204673d0 - x
    else if (x <= 0.5d0) then
        tmp = 0.918938533204673d0 - (y * 0.5d0)
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = 0.918938533204673 + (x * y);
	double tmp;
	if (x <= -7.4e+264) {
		tmp = 0.918938533204673 - x;
	} else if (x <= -2.6e+20) {
		tmp = t_0;
	} else if (x <= -1e-13) {
		tmp = 0.918938533204673 - x;
	} else if (x <= 0.5) {
		tmp = 0.918938533204673 - (y * 0.5);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 0.918938533204673 + (x * y)
	tmp = 0
	if x <= -7.4e+264:
		tmp = 0.918938533204673 - x
	elif x <= -2.6e+20:
		tmp = t_0
	elif x <= -1e-13:
		tmp = 0.918938533204673 - x
	elif x <= 0.5:
		tmp = 0.918938533204673 - (y * 0.5)
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(0.918938533204673 + Float64(x * y))
	tmp = 0.0
	if (x <= -7.4e+264)
		tmp = Float64(0.918938533204673 - x);
	elseif (x <= -2.6e+20)
		tmp = t_0;
	elseif (x <= -1e-13)
		tmp = Float64(0.918938533204673 - x);
	elseif (x <= 0.5)
		tmp = Float64(0.918938533204673 - Float64(y * 0.5));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 0.918938533204673 + (x * y);
	tmp = 0.0;
	if (x <= -7.4e+264)
		tmp = 0.918938533204673 - x;
	elseif (x <= -2.6e+20)
		tmp = t_0;
	elseif (x <= -1e-13)
		tmp = 0.918938533204673 - x;
	elseif (x <= 0.5)
		tmp = 0.918938533204673 - (y * 0.5);
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(0.918938533204673 + N[(x * y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -7.4e+264], N[(0.918938533204673 - x), $MachinePrecision], If[LessEqual[x, -2.6e+20], t$95$0, If[LessEqual[x, -1e-13], N[(0.918938533204673 - x), $MachinePrecision], If[LessEqual[x, 0.5], N[(0.918938533204673 - N[(y * 0.5), $MachinePrecision]), $MachinePrecision], t$95$0]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.918938533204673 + x \cdot y\\
\mathbf{if}\;x \leq -7.4 \cdot 10^{+264}:\\
\;\;\;\;0.918938533204673 - x\\

\mathbf{elif}\;x \leq -2.6 \cdot 10^{+20}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;x \leq -1 \cdot 10^{-13}:\\
\;\;\;\;0.918938533204673 - x\\

\mathbf{elif}\;x \leq 0.5:\\
\;\;\;\;0.918938533204673 - y \cdot 0.5\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -7.3999999999999998e264 or -2.6e20 < x < -1e-13

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in y around 0 89.0%

      \[\leadsto 0.918938533204673 - \color{blue}{x} \]

    if -7.3999999999999998e264 < x < -2.6e20 or 0.5 < x

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in y around inf 60.7%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(0.5 - x\right)} \]
    5. Taylor expanded in x around inf 60.6%

      \[\leadsto 0.918938533204673 - \color{blue}{-1 \cdot \left(x \cdot y\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg60.6%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(-x \cdot y\right)} \]
      2. distribute-lft-neg-out60.6%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(-x\right) \cdot y} \]
      3. *-commutative60.6%

        \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(-x\right)} \]
    7. Simplified60.6%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(-x\right)} \]

    if -1e-13 < x < 0.5

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around 0 98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{0.5 \cdot y} \]
    5. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
    6. Simplified98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification82.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -7.4 \cdot 10^{+264}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;x \leq -2.6 \cdot 10^{+20}:\\ \;\;\;\;0.918938533204673 + x \cdot y\\ \mathbf{elif}\;x \leq -1 \cdot 10^{-13}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;x \leq 0.5:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 + x \cdot y\\ \end{array} \]

Alternative 3: 98.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 0.00025\right):\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -1e-13) (not (<= x 0.00025)))
   (+ 0.918938533204673 (* x (+ y -1.0)))
   (- 0.918938533204673 (* y 0.5))))
double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 0.00025)) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else {
		tmp = 0.918938533204673 - (y * 0.5);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-1d-13)) .or. (.not. (x <= 0.00025d0))) then
        tmp = 0.918938533204673d0 + (x * (y + (-1.0d0)))
    else
        tmp = 0.918938533204673d0 - (y * 0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 0.00025)) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else {
		tmp = 0.918938533204673 - (y * 0.5);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -1e-13) or not (x <= 0.00025):
		tmp = 0.918938533204673 + (x * (y + -1.0))
	else:
		tmp = 0.918938533204673 - (y * 0.5)
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -1e-13) || !(x <= 0.00025))
		tmp = Float64(0.918938533204673 + Float64(x * Float64(y + -1.0)));
	else
		tmp = Float64(0.918938533204673 - Float64(y * 0.5));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -1e-13) || ~((x <= 0.00025)))
		tmp = 0.918938533204673 + (x * (y + -1.0));
	else
		tmp = 0.918938533204673 - (y * 0.5);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -1e-13], N[Not[LessEqual[x, 0.00025]], $MachinePrecision]], N[(0.918938533204673 + N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.918938533204673 - N[(y * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 0.00025\right):\\
\;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\

\mathbf{else}:\\
\;\;\;\;0.918938533204673 - y \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1e-13 or 2.5000000000000001e-4 < x

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around inf 99.9%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 + -1 \cdot y\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg99.9%

        \[\leadsto 0.918938533204673 - x \cdot \left(1 + \color{blue}{\left(-y\right)}\right) \]
      2. unsub-neg99.9%

        \[\leadsto 0.918938533204673 - x \cdot \color{blue}{\left(1 - y\right)} \]
    6. Simplified99.9%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 - y\right)} \]

    if -1e-13 < x < 2.5000000000000001e-4

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around 0 98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{0.5 \cdot y} \]
    5. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
    6. Simplified98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 0.00025\right):\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \]

Alternative 4: 98.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 1.25\right):\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -1e-13) (not (<= x 1.25)))
   (+ 0.918938533204673 (* x (+ y -1.0)))
   (+ 0.918938533204673 (* y (- x 0.5)))))
double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 1.25)) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else {
		tmp = 0.918938533204673 + (y * (x - 0.5));
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-1d-13)) .or. (.not. (x <= 1.25d0))) then
        tmp = 0.918938533204673d0 + (x * (y + (-1.0d0)))
    else
        tmp = 0.918938533204673d0 + (y * (x - 0.5d0))
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 1.25)) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else {
		tmp = 0.918938533204673 + (y * (x - 0.5));
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -1e-13) or not (x <= 1.25):
		tmp = 0.918938533204673 + (x * (y + -1.0))
	else:
		tmp = 0.918938533204673 + (y * (x - 0.5))
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -1e-13) || !(x <= 1.25))
		tmp = Float64(0.918938533204673 + Float64(x * Float64(y + -1.0)));
	else
		tmp = Float64(0.918938533204673 + Float64(y * Float64(x - 0.5)));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -1e-13) || ~((x <= 1.25)))
		tmp = 0.918938533204673 + (x * (y + -1.0));
	else
		tmp = 0.918938533204673 + (y * (x - 0.5));
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -1e-13], N[Not[LessEqual[x, 1.25]], $MachinePrecision]], N[(0.918938533204673 + N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.918938533204673 + N[(y * N[(x - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 1.25\right):\\
\;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\

\mathbf{else}:\\
\;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1e-13 or 1.25 < x

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around inf 99.9%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 + -1 \cdot y\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg99.9%

        \[\leadsto 0.918938533204673 - x \cdot \left(1 + \color{blue}{\left(-y\right)}\right) \]
      2. unsub-neg99.9%

        \[\leadsto 0.918938533204673 - x \cdot \color{blue}{\left(1 - y\right)} \]
    6. Simplified99.9%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 - y\right)} \]

    if -1e-13 < x < 1.25

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in y around inf 100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(0.5 - x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 1.25\right):\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\ \end{array} \]

Alternative 5: 98.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13}:\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{elif}\;x \leq 1.4:\\ \;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 + \left(x \cdot y - x\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x -1e-13)
   (+ 0.918938533204673 (* x (+ y -1.0)))
   (if (<= x 1.4)
     (+ 0.918938533204673 (* y (- x 0.5)))
     (+ 0.918938533204673 (- (* x y) x)))))
double code(double x, double y) {
	double tmp;
	if (x <= -1e-13) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else if (x <= 1.4) {
		tmp = 0.918938533204673 + (y * (x - 0.5));
	} else {
		tmp = 0.918938533204673 + ((x * y) - x);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= (-1d-13)) then
        tmp = 0.918938533204673d0 + (x * (y + (-1.0d0)))
    else if (x <= 1.4d0) then
        tmp = 0.918938533204673d0 + (y * (x - 0.5d0))
    else
        tmp = 0.918938533204673d0 + ((x * y) - x)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= -1e-13) {
		tmp = 0.918938533204673 + (x * (y + -1.0));
	} else if (x <= 1.4) {
		tmp = 0.918938533204673 + (y * (x - 0.5));
	} else {
		tmp = 0.918938533204673 + ((x * y) - x);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= -1e-13:
		tmp = 0.918938533204673 + (x * (y + -1.0))
	elif x <= 1.4:
		tmp = 0.918938533204673 + (y * (x - 0.5))
	else:
		tmp = 0.918938533204673 + ((x * y) - x)
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= -1e-13)
		tmp = Float64(0.918938533204673 + Float64(x * Float64(y + -1.0)));
	elseif (x <= 1.4)
		tmp = Float64(0.918938533204673 + Float64(y * Float64(x - 0.5)));
	else
		tmp = Float64(0.918938533204673 + Float64(Float64(x * y) - x));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= -1e-13)
		tmp = 0.918938533204673 + (x * (y + -1.0));
	elseif (x <= 1.4)
		tmp = 0.918938533204673 + (y * (x - 0.5));
	else
		tmp = 0.918938533204673 + ((x * y) - x);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, -1e-13], N[(0.918938533204673 + N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 1.4], N[(0.918938533204673 + N[(y * N[(x - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.918938533204673 + N[(N[(x * y), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{-13}:\\
\;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\

\mathbf{elif}\;x \leq 1.4:\\
\;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;0.918938533204673 + \left(x \cdot y - x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1e-13

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around inf 100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 + -1 \cdot y\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg100.0%

        \[\leadsto 0.918938533204673 - x \cdot \left(1 + \color{blue}{\left(-y\right)}\right) \]
      2. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - x \cdot \color{blue}{\left(1 - y\right)} \]
    6. Simplified100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{x \cdot \left(1 - y\right)} \]

    if -1e-13 < x < 1.3999999999999999

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in y around inf 100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(0.5 - x\right)} \]

    if 1.3999999999999999 < x

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Step-by-step derivation
      1. fma-udef100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(y \cdot \left(0.5 - x\right) + x\right)} \]
    5. Applied egg-rr100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\left(y \cdot \left(0.5 - x\right) + x\right)} \]
    6. Taylor expanded in x around inf 99.8%

      \[\leadsto 0.918938533204673 - \left(\color{blue}{-1 \cdot \left(x \cdot y\right)} + x\right) \]
    7. Step-by-step derivation
      1. mul-1-neg60.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(-x \cdot y\right)} \]
      2. distribute-lft-neg-out60.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(-x\right) \cdot y} \]
      3. *-commutative60.0%

        \[\leadsto 0.918938533204673 - \color{blue}{y \cdot \left(-x\right)} \]
    8. Simplified99.8%

      \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(-x\right)} + x\right) \]
    9. Step-by-step derivation
      1. +-commutative99.8%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(x + y \cdot \left(-x\right)\right)} \]
      2. distribute-rgt-neg-out99.8%

        \[\leadsto 0.918938533204673 - \left(x + \color{blue}{\left(-y \cdot x\right)}\right) \]
      3. unsub-neg99.8%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(x - y \cdot x\right)} \]
    10. Applied egg-rr99.8%

      \[\leadsto 0.918938533204673 - \color{blue}{\left(x - y \cdot x\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13}:\\ \;\;\;\;0.918938533204673 + x \cdot \left(y + -1\right)\\ \mathbf{elif}\;x \leq 1.4:\\ \;\;\;\;0.918938533204673 + y \cdot \left(x - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 + \left(x \cdot y - x\right)\\ \end{array} \]

Alternative 6: 74.1% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 6.8 \cdot 10^{-5}\right):\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -1e-13) (not (<= x 6.8e-5)))
   (- 0.918938533204673 x)
   (- 0.918938533204673 (* y 0.5))))
double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 6.8e-5)) {
		tmp = 0.918938533204673 - x;
	} else {
		tmp = 0.918938533204673 - (y * 0.5);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-1d-13)) .or. (.not. (x <= 6.8d-5))) then
        tmp = 0.918938533204673d0 - x
    else
        tmp = 0.918938533204673d0 - (y * 0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -1e-13) || !(x <= 6.8e-5)) {
		tmp = 0.918938533204673 - x;
	} else {
		tmp = 0.918938533204673 - (y * 0.5);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -1e-13) or not (x <= 6.8e-5):
		tmp = 0.918938533204673 - x
	else:
		tmp = 0.918938533204673 - (y * 0.5)
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -1e-13) || !(x <= 6.8e-5))
		tmp = Float64(0.918938533204673 - x);
	else
		tmp = Float64(0.918938533204673 - Float64(y * 0.5));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -1e-13) || ~((x <= 6.8e-5)))
		tmp = 0.918938533204673 - x;
	else
		tmp = 0.918938533204673 - (y * 0.5);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -1e-13], N[Not[LessEqual[x, 6.8e-5]], $MachinePrecision]], N[(0.918938533204673 - x), $MachinePrecision], N[(0.918938533204673 - N[(y * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 6.8 \cdot 10^{-5}\right):\\
\;\;\;\;0.918938533204673 - x\\

\mathbf{else}:\\
\;\;\;\;0.918938533204673 - y \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1e-13 or 6.7999999999999999e-5 < x

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in y around 0 47.6%

      \[\leadsto 0.918938533204673 - \color{blue}{x} \]

    if -1e-13 < x < 6.7999999999999999e-5

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
      2. cancel-sign-sub-inv100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
      3. +-commutative100.0%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
      4. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
      5. cancel-sign-sub-inv100.0%

        \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
      6. associate-+l-100.0%

        \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
      7. sub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
      8. distribute-rgt-in100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
      9. metadata-eval100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
      10. neg-mul-1100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
      11. associate--r+100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
      12. distribute-lft-out--100.0%

        \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
      13. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
      14. fma-neg100.0%

        \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
      15. unsub-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
      16. remove-double-neg100.0%

        \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
    4. Taylor expanded in x around 0 98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{0.5 \cdot y} \]
    5. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
    6. Simplified98.7%

      \[\leadsto 0.918938533204673 - \color{blue}{y \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \cdot 10^{-13} \lor \neg \left(x \leq 6.8 \cdot 10^{-5}\right):\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \]

Alternative 7: 100.0% accurate, 1.2× speedup?

\[\begin{array}{l} \\ 0.918938533204673 + \left(y \cdot \left(x - 0.5\right) - x\right) \end{array} \]
(FPCore (x y) :precision binary64 (+ 0.918938533204673 (- (* y (- x 0.5)) x)))
double code(double x, double y) {
	return 0.918938533204673 + ((y * (x - 0.5)) - x);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = 0.918938533204673d0 + ((y * (x - 0.5d0)) - x)
end function
public static double code(double x, double y) {
	return 0.918938533204673 + ((y * (x - 0.5)) - x);
}
def code(x, y):
	return 0.918938533204673 + ((y * (x - 0.5)) - x)
function code(x, y)
	return Float64(0.918938533204673 + Float64(Float64(y * Float64(x - 0.5)) - x))
end
function tmp = code(x, y)
	tmp = 0.918938533204673 + ((y * (x - 0.5)) - x);
end
code[x_, y_] := N[(0.918938533204673 + N[(N[(y * N[(x - 0.5), $MachinePrecision]), $MachinePrecision] - x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.918938533204673 + \left(y \cdot \left(x - 0.5\right) - x\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
  2. Step-by-step derivation
    1. +-commutative100.0%

      \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
    2. cancel-sign-sub-inv100.0%

      \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
    3. +-commutative100.0%

      \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
    4. associate-+r+100.0%

      \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
    5. cancel-sign-sub-inv100.0%

      \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
    6. associate-+l-100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
    7. sub-neg100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
    8. distribute-rgt-in100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
    9. metadata-eval100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
    10. neg-mul-1100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
    11. associate--r+100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
    12. distribute-lft-out--100.0%

      \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
    13. unsub-neg100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
    14. fma-neg100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
    15. unsub-neg100.0%

      \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
    16. remove-double-neg100.0%

      \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
  4. Step-by-step derivation
    1. fma-udef100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\left(y \cdot \left(0.5 - x\right) + x\right)} \]
  5. Applied egg-rr100.0%

    \[\leadsto 0.918938533204673 - \color{blue}{\left(y \cdot \left(0.5 - x\right) + x\right)} \]
  6. Final simplification100.0%

    \[\leadsto 0.918938533204673 + \left(y \cdot \left(x - 0.5\right) - x\right) \]

Alternative 8: 49.7% accurate, 3.7× speedup?

\[\begin{array}{l} \\ 0.918938533204673 - x \end{array} \]
(FPCore (x y) :precision binary64 (- 0.918938533204673 x))
double code(double x, double y) {
	return 0.918938533204673 - x;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = 0.918938533204673d0 - x
end function
public static double code(double x, double y) {
	return 0.918938533204673 - x;
}
def code(x, y):
	return 0.918938533204673 - x
function code(x, y)
	return Float64(0.918938533204673 - x)
end
function tmp = code(x, y)
	tmp = 0.918938533204673 - x;
end
code[x_, y_] := N[(0.918938533204673 - x), $MachinePrecision]
\begin{array}{l}

\\
0.918938533204673 - x
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
  2. Step-by-step derivation
    1. +-commutative100.0%

      \[\leadsto \color{blue}{0.918938533204673 + \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right)} \]
    2. cancel-sign-sub-inv100.0%

      \[\leadsto 0.918938533204673 + \color{blue}{\left(x \cdot \left(y - 1\right) + \left(-y\right) \cdot 0.5\right)} \]
    3. +-commutative100.0%

      \[\leadsto 0.918938533204673 + \color{blue}{\left(\left(-y\right) \cdot 0.5 + x \cdot \left(y - 1\right)\right)} \]
    4. associate-+r+100.0%

      \[\leadsto \color{blue}{\left(0.918938533204673 + \left(-y\right) \cdot 0.5\right) + x \cdot \left(y - 1\right)} \]
    5. cancel-sign-sub-inv100.0%

      \[\leadsto \color{blue}{\left(0.918938533204673 - y \cdot 0.5\right)} + x \cdot \left(y - 1\right) \]
    6. associate-+l-100.0%

      \[\leadsto \color{blue}{0.918938533204673 - \left(y \cdot 0.5 - x \cdot \left(y - 1\right)\right)} \]
    7. sub-neg100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) \]
    8. distribute-rgt-in100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) \]
    9. metadata-eval100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{-1} \cdot x\right)\right) \]
    10. neg-mul-1100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot 0.5 - \left(y \cdot x + \color{blue}{\left(-x\right)}\right)\right) \]
    11. associate--r+100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\left(\left(y \cdot 0.5 - y \cdot x\right) - \left(-x\right)\right)} \]
    12. distribute-lft-out--100.0%

      \[\leadsto 0.918938533204673 - \left(\color{blue}{y \cdot \left(0.5 - x\right)} - \left(-x\right)\right) \]
    13. unsub-neg100.0%

      \[\leadsto 0.918938533204673 - \left(y \cdot \color{blue}{\left(0.5 + \left(-x\right)\right)} - \left(-x\right)\right) \]
    14. fma-neg100.0%

      \[\leadsto 0.918938533204673 - \color{blue}{\mathsf{fma}\left(y, 0.5 + \left(-x\right), -\left(-x\right)\right)} \]
    15. unsub-neg100.0%

      \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, \color{blue}{0.5 - x}, -\left(-x\right)\right) \]
    16. remove-double-neg100.0%

      \[\leadsto 0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, \color{blue}{x}\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(y, 0.5 - x, x\right)} \]
  4. Taylor expanded in y around 0 48.6%

    \[\leadsto 0.918938533204673 - \color{blue}{x} \]
  5. Final simplification48.6%

    \[\leadsto 0.918938533204673 - x \]

Reproduce

?
herbie shell --seed 2023308 
(FPCore (x y)
  :name "Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, A"
  :precision binary64
  (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))