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

Percentage Accurate: 100.0% → 100.0%
Time: 4.2s
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?

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

\\
0.918938533204673 - \left(y \cdot 0.5 + x \cdot \left(1 - y\right)\right)
\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%

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

Alternative 2: 98.5% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -620000 \lor \neg \left(x \leq 112\right):\\ \;\;\;\;x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y + \left(0.918938533204673 - y \cdot 0.5\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -620000.0) (not (<= x 112.0)))
   (* x (+ y -1.0))
   (+ (* x y) (- 0.918938533204673 (* y 0.5)))))
double code(double x, double y) {
	double tmp;
	if ((x <= -620000.0) || !(x <= 112.0)) {
		tmp = x * (y + -1.0);
	} else {
		tmp = (x * y) + (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 <= (-620000.0d0)) .or. (.not. (x <= 112.0d0))) then
        tmp = x * (y + (-1.0d0))
    else
        tmp = (x * y) + (0.918938533204673d0 - (y * 0.5d0))
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -620000.0) || !(x <= 112.0)) {
		tmp = x * (y + -1.0);
	} else {
		tmp = (x * y) + (0.918938533204673 - (y * 0.5));
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -620000.0) or not (x <= 112.0):
		tmp = x * (y + -1.0)
	else:
		tmp = (x * y) + (0.918938533204673 - (y * 0.5))
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -620000.0) || !(x <= 112.0))
		tmp = Float64(x * Float64(y + -1.0));
	else
		tmp = Float64(Float64(x * y) + Float64(0.918938533204673 - Float64(y * 0.5)));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -620000.0) || ~((x <= 112.0)))
		tmp = x * (y + -1.0);
	else
		tmp = (x * y) + (0.918938533204673 - (y * 0.5));
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -620000.0], N[Not[LessEqual[x, 112.0]], $MachinePrecision]], N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision], N[(N[(x * y), $MachinePrecision] + N[(0.918938533204673 - N[(y * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -620000 \lor \neg \left(x \leq 112\right):\\
\;\;\;\;x \cdot \left(y + -1\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -6.2e5 or 112 < 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. sub-neg100.0%

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

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

        \[\leadsto \left(\left(-y \cdot 0.5\right) + x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) + 0.918938533204673 \]
      4. distribute-rgt-in99.9%

        \[\leadsto \left(\left(-y \cdot 0.5\right) + \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) + 0.918938533204673 \]
      5. associate-+r+99.9%

        \[\leadsto \color{blue}{\left(\left(\left(-y \cdot 0.5\right) + y \cdot x\right) + \left(-1\right) \cdot x\right)} + 0.918938533204673 \]
      6. associate-+l+99.9%

        \[\leadsto \color{blue}{\left(\left(-y \cdot 0.5\right) + y \cdot x\right) + \left(\left(-1\right) \cdot x + 0.918938533204673\right)} \]
      7. distribute-rgt-neg-in99.9%

        \[\leadsto \left(\color{blue}{y \cdot \left(-0.5\right)} + y \cdot x\right) + \left(\left(-1\right) \cdot x + 0.918938533204673\right) \]
      8. distribute-lft-out100.0%

        \[\leadsto \color{blue}{y \cdot \left(\left(-0.5\right) + x\right)} + \left(\left(-1\right) \cdot x + 0.918938533204673\right) \]
      9. fma-def100.0%

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

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

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

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

        \[\leadsto \mathsf{fma}\left(y, x + -0.5, \color{blue}{0.918938533204673 - 1 \cdot x}\right) \]
      14. *-lft-identity100.0%

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(y, x + -0.5, 0.918938533204673 - x\right)} \]
    4. Taylor expanded in x around -inf 99.1%

      \[\leadsto \color{blue}{-1 \cdot \left(\left(1 + -1 \cdot y\right) \cdot x\right)} \]
    5. Taylor expanded in y around 0 99.0%

      \[\leadsto -1 \cdot \color{blue}{\left(-1 \cdot \left(y \cdot x\right) + x\right)} \]
    6. Step-by-step derivation
      1. +-commutative99.0%

        \[\leadsto -1 \cdot \color{blue}{\left(x + -1 \cdot \left(y \cdot x\right)\right)} \]
      2. mul-1-neg99.0%

        \[\leadsto -1 \cdot \left(x + \color{blue}{\left(-y \cdot x\right)}\right) \]
      3. unsub-neg99.0%

        \[\leadsto -1 \cdot \color{blue}{\left(x - y \cdot x\right)} \]
    7. Simplified99.0%

      \[\leadsto -1 \cdot \color{blue}{\left(x - y \cdot x\right)} \]
    8. Taylor expanded in x around 0 99.1%

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

    if -6.2e5 < x < 112

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 98.8%

      \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -620000 \lor \neg \left(x \leq 112\right):\\ \;\;\;\;x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;x \cdot y + \left(0.918938533204673 - y \cdot 0.5\right)\\ \end{array} \]

Alternative 3: 49.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -3.4 \cdot 10^{+28}:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq -11.4:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673\\ \mathbf{elif}\;y \leq 2.25 \cdot 10^{+246}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -3.4e+28)
   (* x y)
   (if (<= y -11.4)
     (* y -0.5)
     (if (<= y 1.5)
       0.918938533204673
       (if (<= y 2.25e+246) (* y -0.5) (* x y))))))
double code(double x, double y) {
	double tmp;
	if (y <= -3.4e+28) {
		tmp = x * y;
	} else if (y <= -11.4) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673;
	} else if (y <= 2.25e+246) {
		tmp = y * -0.5;
	} else {
		tmp = x * y;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-3.4d+28)) then
        tmp = x * y
    else if (y <= (-11.4d0)) then
        tmp = y * (-0.5d0)
    else if (y <= 1.5d0) then
        tmp = 0.918938533204673d0
    else if (y <= 2.25d+246) then
        tmp = y * (-0.5d0)
    else
        tmp = x * y
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -3.4e+28) {
		tmp = x * y;
	} else if (y <= -11.4) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673;
	} else if (y <= 2.25e+246) {
		tmp = y * -0.5;
	} else {
		tmp = x * y;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -3.4e+28:
		tmp = x * y
	elif y <= -11.4:
		tmp = y * -0.5
	elif y <= 1.5:
		tmp = 0.918938533204673
	elif y <= 2.25e+246:
		tmp = y * -0.5
	else:
		tmp = x * y
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -3.4e+28)
		tmp = Float64(x * y);
	elseif (y <= -11.4)
		tmp = Float64(y * -0.5);
	elseif (y <= 1.5)
		tmp = 0.918938533204673;
	elseif (y <= 2.25e+246)
		tmp = Float64(y * -0.5);
	else
		tmp = Float64(x * y);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -3.4e+28)
		tmp = x * y;
	elseif (y <= -11.4)
		tmp = y * -0.5;
	elseif (y <= 1.5)
		tmp = 0.918938533204673;
	elseif (y <= 2.25e+246)
		tmp = y * -0.5;
	else
		tmp = x * y;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -3.4e+28], N[(x * y), $MachinePrecision], If[LessEqual[y, -11.4], N[(y * -0.5), $MachinePrecision], If[LessEqual[y, 1.5], 0.918938533204673, If[LessEqual[y, 2.25e+246], N[(y * -0.5), $MachinePrecision], N[(x * y), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -3.4 \cdot 10^{+28}:\\
\;\;\;\;x \cdot y\\

\mathbf{elif}\;y \leq -11.4:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{elif}\;y \leq 1.5:\\
\;\;\;\;0.918938533204673\\

\mathbf{elif}\;y \leq 2.25 \cdot 10^{+246}:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{else}:\\
\;\;\;\;x \cdot y\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -3.4e28 or 2.25e246 < y

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 100.0%

      \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    5. Taylor expanded in x around inf 58.3%

      \[\leadsto \color{blue}{y \cdot x} \]

    if -3.4e28 < y < -11.4000000000000004 or 1.5 < y < 2.25e246

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 95.3%

      \[\leadsto \color{blue}{y \cdot \left(x - 0.5\right)} \]
    5. Taylor expanded in x around 0 61.1%

      \[\leadsto \color{blue}{-0.5 \cdot y} \]
    6. Step-by-step derivation
      1. *-commutative61.1%

        \[\leadsto \color{blue}{y \cdot -0.5} \]
    7. Simplified61.1%

      \[\leadsto \color{blue}{y \cdot -0.5} \]

    if -11.4000000000000004 < y < 1.5

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 55.8%

      \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    5. Taylor expanded in y around 0 54.0%

      \[\leadsto \color{blue}{0.918938533204673} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification56.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -3.4 \cdot 10^{+28}:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq -11.4:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673\\ \mathbf{elif}\;y \leq 2.25 \cdot 10^{+246}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \]

Alternative 4: 74.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.15 \cdot 10^{+28}:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq -222:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;y \leq 4 \cdot 10^{+242}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.15e+28)
   (* x y)
   (if (<= y -222.0)
     (* y -0.5)
     (if (<= y 1.5)
       (- 0.918938533204673 x)
       (if (<= y 4e+242) (* y -0.5) (* x y))))))
double code(double x, double y) {
	double tmp;
	if (y <= -1.15e+28) {
		tmp = x * y;
	} else if (y <= -222.0) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673 - x;
	} else if (y <= 4e+242) {
		tmp = y * -0.5;
	} else {
		tmp = x * y;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-1.15d+28)) then
        tmp = x * y
    else if (y <= (-222.0d0)) then
        tmp = y * (-0.5d0)
    else if (y <= 1.5d0) then
        tmp = 0.918938533204673d0 - x
    else if (y <= 4d+242) then
        tmp = y * (-0.5d0)
    else
        tmp = x * y
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.15e+28) {
		tmp = x * y;
	} else if (y <= -222.0) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673 - x;
	} else if (y <= 4e+242) {
		tmp = y * -0.5;
	} else {
		tmp = x * y;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.15e+28:
		tmp = x * y
	elif y <= -222.0:
		tmp = y * -0.5
	elif y <= 1.5:
		tmp = 0.918938533204673 - x
	elif y <= 4e+242:
		tmp = y * -0.5
	else:
		tmp = x * y
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.15e+28)
		tmp = Float64(x * y);
	elseif (y <= -222.0)
		tmp = Float64(y * -0.5);
	elseif (y <= 1.5)
		tmp = Float64(0.918938533204673 - x);
	elseif (y <= 4e+242)
		tmp = Float64(y * -0.5);
	else
		tmp = Float64(x * y);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.15e+28)
		tmp = x * y;
	elseif (y <= -222.0)
		tmp = y * -0.5;
	elseif (y <= 1.5)
		tmp = 0.918938533204673 - x;
	elseif (y <= 4e+242)
		tmp = y * -0.5;
	else
		tmp = x * y;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.15e+28], N[(x * y), $MachinePrecision], If[LessEqual[y, -222.0], N[(y * -0.5), $MachinePrecision], If[LessEqual[y, 1.5], N[(0.918938533204673 - x), $MachinePrecision], If[LessEqual[y, 4e+242], N[(y * -0.5), $MachinePrecision], N[(x * y), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.15 \cdot 10^{+28}:\\
\;\;\;\;x \cdot y\\

\mathbf{elif}\;y \leq -222:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{elif}\;y \leq 1.5:\\
\;\;\;\;0.918938533204673 - x\\

\mathbf{elif}\;y \leq 4 \cdot 10^{+242}:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{else}:\\
\;\;\;\;x \cdot y\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -1.14999999999999992e28 or 4.0000000000000002e242 < y

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 100.0%

      \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    5. Taylor expanded in x around inf 58.3%

      \[\leadsto \color{blue}{y \cdot x} \]

    if -1.14999999999999992e28 < y < -222 or 1.5 < y < 4.0000000000000002e242

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 95.3%

      \[\leadsto \color{blue}{y \cdot \left(x - 0.5\right)} \]
    5. Taylor expanded in x around 0 61.1%

      \[\leadsto \color{blue}{-0.5 \cdot y} \]
    6. Step-by-step derivation
      1. *-commutative61.1%

        \[\leadsto \color{blue}{y \cdot -0.5} \]
    7. Simplified61.1%

      \[\leadsto \color{blue}{y \cdot -0.5} \]

    if -222 < y < 1.5

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around 0 97.3%

      \[\leadsto \color{blue}{0.918938533204673 + -1 \cdot x} \]
    5. Step-by-step derivation
      1. neg-mul-197.3%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(-x\right)} \]
      2. sub-neg97.3%

        \[\leadsto \color{blue}{0.918938533204673 - x} \]
    6. Simplified97.3%

      \[\leadsto \color{blue}{0.918938533204673 - x} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification79.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.15 \cdot 10^{+28}:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq -222:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{elif}\;y \leq 4 \cdot 10^{+242}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \]

Alternative 5: 97.8% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.45 \lor \neg \left(y \leq 1\right):\\ \;\;\;\;y \cdot \left(x - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - x\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= y -1.45) (not (<= y 1.0)))
   (* y (- x 0.5))
   (- 0.918938533204673 x)))
double code(double x, double y) {
	double tmp;
	if ((y <= -1.45) || !(y <= 1.0)) {
		tmp = y * (x - 0.5);
	} else {
		tmp = 0.918938533204673 - x;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((y <= (-1.45d0)) .or. (.not. (y <= 1.0d0))) then
        tmp = y * (x - 0.5d0)
    else
        tmp = 0.918938533204673d0 - x
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((y <= -1.45) || !(y <= 1.0)) {
		tmp = y * (x - 0.5);
	} else {
		tmp = 0.918938533204673 - x;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (y <= -1.45) or not (y <= 1.0):
		tmp = y * (x - 0.5)
	else:
		tmp = 0.918938533204673 - x
	return tmp
function code(x, y)
	tmp = 0.0
	if ((y <= -1.45) || !(y <= 1.0))
		tmp = Float64(y * Float64(x - 0.5));
	else
		tmp = Float64(0.918938533204673 - x);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((y <= -1.45) || ~((y <= 1.0)))
		tmp = y * (x - 0.5);
	else
		tmp = 0.918938533204673 - x;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[y, -1.45], N[Not[LessEqual[y, 1.0]], $MachinePrecision]], N[(y * N[(x - 0.5), $MachinePrecision]), $MachinePrecision], N[(0.918938533204673 - x), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.45 \lor \neg \left(y \leq 1\right):\\
\;\;\;\;y \cdot \left(x - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;0.918938533204673 - x\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.44999999999999996 or 1 < y

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 97.1%

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

    if -1.44999999999999996 < y < 1

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around 0 97.9%

      \[\leadsto \color{blue}{0.918938533204673 + -1 \cdot x} \]
    5. Step-by-step derivation
      1. neg-mul-197.9%

        \[\leadsto 0.918938533204673 + \color{blue}{\left(-x\right)} \]
      2. sub-neg97.9%

        \[\leadsto \color{blue}{0.918938533204673 - x} \]
    6. Simplified97.9%

      \[\leadsto \color{blue}{0.918938533204673 - x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.45 \lor \neg \left(y \leq 1\right):\\ \;\;\;\;y \cdot \left(x - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - x\\ \end{array} \]

Alternative 6: 97.9% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -0.62 \lor \neg \left(x \leq 0.85\right):\\ \;\;\;\;x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -0.62) (not (<= x 0.85)))
   (* x (+ y -1.0))
   (- 0.918938533204673 (* y 0.5))))
double code(double x, double y) {
	double tmp;
	if ((x <= -0.62) || !(x <= 0.85)) {
		tmp = 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 <= (-0.62d0)) .or. (.not. (x <= 0.85d0))) then
        tmp = 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 <= -0.62) || !(x <= 0.85)) {
		tmp = x * (y + -1.0);
	} else {
		tmp = 0.918938533204673 - (y * 0.5);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -0.62) or not (x <= 0.85):
		tmp = x * (y + -1.0)
	else:
		tmp = 0.918938533204673 - (y * 0.5)
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -0.62) || !(x <= 0.85))
		tmp = 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 <= -0.62) || ~((x <= 0.85)))
		tmp = x * (y + -1.0);
	else
		tmp = 0.918938533204673 - (y * 0.5);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -0.62], N[Not[LessEqual[x, 0.85]], $MachinePrecision]], N[(x * N[(y + -1.0), $MachinePrecision]), $MachinePrecision], N[(0.918938533204673 - N[(y * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -0.62 \lor \neg \left(x \leq 0.85\right):\\
\;\;\;\;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 < -0.619999999999999996 or 0.849999999999999978 < 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. sub-neg100.0%

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

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

        \[\leadsto \left(\left(-y \cdot 0.5\right) + x \cdot \color{blue}{\left(y + \left(-1\right)\right)}\right) + 0.918938533204673 \]
      4. distribute-rgt-in99.9%

        \[\leadsto \left(\left(-y \cdot 0.5\right) + \color{blue}{\left(y \cdot x + \left(-1\right) \cdot x\right)}\right) + 0.918938533204673 \]
      5. associate-+r+99.9%

        \[\leadsto \color{blue}{\left(\left(\left(-y \cdot 0.5\right) + y \cdot x\right) + \left(-1\right) \cdot x\right)} + 0.918938533204673 \]
      6. associate-+l+99.9%

        \[\leadsto \color{blue}{\left(\left(-y \cdot 0.5\right) + y \cdot x\right) + \left(\left(-1\right) \cdot x + 0.918938533204673\right)} \]
      7. distribute-rgt-neg-in99.9%

        \[\leadsto \left(\color{blue}{y \cdot \left(-0.5\right)} + y \cdot x\right) + \left(\left(-1\right) \cdot x + 0.918938533204673\right) \]
      8. distribute-lft-out100.0%

        \[\leadsto \color{blue}{y \cdot \left(\left(-0.5\right) + x\right)} + \left(\left(-1\right) \cdot x + 0.918938533204673\right) \]
      9. fma-def100.0%

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

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

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

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

        \[\leadsto \mathsf{fma}\left(y, x + -0.5, \color{blue}{0.918938533204673 - 1 \cdot x}\right) \]
      14. *-lft-identity100.0%

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(y, x + -0.5, 0.918938533204673 - x\right)} \]
    4. Taylor expanded in x around -inf 98.6%

      \[\leadsto \color{blue}{-1 \cdot \left(\left(1 + -1 \cdot y\right) \cdot x\right)} \]
    5. Taylor expanded in y around 0 98.5%

      \[\leadsto -1 \cdot \color{blue}{\left(-1 \cdot \left(y \cdot x\right) + x\right)} \]
    6. Step-by-step derivation
      1. +-commutative98.5%

        \[\leadsto -1 \cdot \color{blue}{\left(x + -1 \cdot \left(y \cdot x\right)\right)} \]
      2. mul-1-neg98.5%

        \[\leadsto -1 \cdot \left(x + \color{blue}{\left(-y \cdot x\right)}\right) \]
      3. unsub-neg98.5%

        \[\leadsto -1 \cdot \color{blue}{\left(x - y \cdot x\right)} \]
    7. Simplified98.5%

      \[\leadsto -1 \cdot \color{blue}{\left(x - y \cdot x\right)} \]
    8. Taylor expanded in x around 0 98.6%

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

    if -0.619999999999999996 < x < 0.849999999999999978

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in x around 0 98.6%

      \[\leadsto \color{blue}{0.918938533204673 - 0.5 \cdot y} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -0.62 \lor \neg \left(x \leq 0.85\right):\\ \;\;\;\;x \cdot \left(y + -1\right)\\ \mathbf{else}:\\ \;\;\;\;0.918938533204673 - y \cdot 0.5\\ \end{array} \]

Alternative 7: 49.4% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -11.4:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673\\ \mathbf{else}:\\ \;\;\;\;y \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -11.4) (* y -0.5) (if (<= y 1.5) 0.918938533204673 (* y -0.5))))
double code(double x, double y) {
	double tmp;
	if (y <= -11.4) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673;
	} else {
		tmp = 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 (y <= (-11.4d0)) then
        tmp = y * (-0.5d0)
    else if (y <= 1.5d0) then
        tmp = 0.918938533204673d0
    else
        tmp = y * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -11.4) {
		tmp = y * -0.5;
	} else if (y <= 1.5) {
		tmp = 0.918938533204673;
	} else {
		tmp = y * -0.5;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -11.4:
		tmp = y * -0.5
	elif y <= 1.5:
		tmp = 0.918938533204673
	else:
		tmp = y * -0.5
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -11.4)
		tmp = Float64(y * -0.5);
	elseif (y <= 1.5)
		tmp = 0.918938533204673;
	else
		tmp = Float64(y * -0.5);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -11.4)
		tmp = y * -0.5;
	elseif (y <= 1.5)
		tmp = 0.918938533204673;
	else
		tmp = y * -0.5;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -11.4], N[(y * -0.5), $MachinePrecision], If[LessEqual[y, 1.5], 0.918938533204673, N[(y * -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -11.4:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{elif}\;y \leq 1.5:\\
\;\;\;\;0.918938533204673\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -11.4000000000000004 or 1.5 < y

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 97.7%

      \[\leadsto \color{blue}{y \cdot \left(x - 0.5\right)} \]
    5. Taylor expanded in x around 0 51.8%

      \[\leadsto \color{blue}{-0.5 \cdot y} \]
    6. Step-by-step derivation
      1. *-commutative51.8%

        \[\leadsto \color{blue}{y \cdot -0.5} \]
    7. Simplified51.8%

      \[\leadsto \color{blue}{y \cdot -0.5} \]

    if -11.4000000000000004 < y < 1.5

    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. associate-+l-100.0%

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

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

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

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
      5. remove-double-neg100.0%

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

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

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

        \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
      9. remove-double-neg100.0%

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

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

        \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
    4. Taylor expanded in y around inf 55.8%

      \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    5. Taylor expanded in y around 0 54.0%

      \[\leadsto \color{blue}{0.918938533204673} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification52.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -11.4:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.5:\\ \;\;\;\;0.918938533204673\\ \mathbf{else}:\\ \;\;\;\;y \cdot -0.5\\ \end{array} \]

Alternative 8: 25.9% accurate, 11.0× speedup?

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

\\
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. Step-by-step derivation
    1. associate-+l-100.0%

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

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

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

      \[\leadsto \mathsf{fma}\left(x, \color{blue}{\left(-1\right) + y}, -\left(y \cdot 0.5 - 0.918938533204673\right)\right) \]
    5. remove-double-neg100.0%

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

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

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

      \[\leadsto x \cdot \color{blue}{\left(\left(-1\right) + \left(-\left(-y\right)\right)\right)} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
    9. remove-double-neg100.0%

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

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

      \[\leadsto x \cdot \left(y + \color{blue}{-1}\right) - \left(y \cdot 0.5 - 0.918938533204673\right) \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{x \cdot \left(y + -1\right) - \left(y \cdot 0.5 - 0.918938533204673\right)} \]
  4. Taylor expanded in y around inf 76.6%

    \[\leadsto \color{blue}{y \cdot x} - \left(y \cdot 0.5 - 0.918938533204673\right) \]
  5. Taylor expanded in y around 0 29.1%

    \[\leadsto \color{blue}{0.918938533204673} \]
  6. Final simplification29.1%

    \[\leadsto 0.918938533204673 \]

Reproduce

?
herbie shell --seed 2023185 
(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))