Data.Array.Repa.Algorithms.ColorRamp:rampColorHotToCold from repa-algorithms-3.4.0.1, B

Percentage Accurate: 99.8% → 99.8%
Time: 6.8s
Alternatives: 9
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \end{array} \]
(FPCore (x y z) :precision binary64 (/ (* 4.0 (- (- x y) (* z 0.5))) z))
double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
end function
public static double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
def code(x, y, z):
	return (4.0 * ((x - y) - (z * 0.5))) / z
function code(x, y, z)
	return Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
end
function tmp = code(x, y, z)
	tmp = (4.0 * ((x - y) - (z * 0.5))) / z;
end
code[x_, y_, z_] := N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]
\begin{array}{l}

\\
\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}
\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 9 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 99.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \end{array} \]
(FPCore (x y z) :precision binary64 (/ (* 4.0 (- (- x y) (* z 0.5))) z))
double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
end function
public static double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
def code(x, y, z):
	return (4.0 * ((x - y) - (z * 0.5))) / z
function code(x, y, z)
	return Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
end
function tmp = code(x, y, z)
	tmp = (4.0 * ((x - y) - (z * 0.5))) / z;
end
code[x_, y_, z_] := N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]
\begin{array}{l}

\\
\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}
\end{array}

Alternative 1: 99.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \end{array} \]
(FPCore (x y z) :precision binary64 (/ (* 4.0 (- (- x y) (* z 0.5))) z))
double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
end function
public static double code(double x, double y, double z) {
	return (4.0 * ((x - y) - (z * 0.5))) / z;
}
def code(x, y, z):
	return (4.0 * ((x - y) - (z * 0.5))) / z
function code(x, y, z)
	return Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
end
function tmp = code(x, y, z)
	tmp = (4.0 * ((x - y) - (z * 0.5))) / z;
end
code[x_, y_, z_] := N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]
\begin{array}{l}

\\
\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
  2. Add Preprocessing
  3. Add Preprocessing

Alternative 2: 97.8% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\ \mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\ \;\;\;\;\frac{\left(y - x\right) \cdot -4}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (/ (* 4.0 (- (- x y) (* z 0.5))) z)))
   (if (or (<= t_0 -5e+29) (not (<= t_0 -1.0)))
     (/ (* (- y x) -4.0) z)
     (fma (/ x z) 4.0 -2.0))))
double code(double x, double y, double z) {
	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
	double tmp;
	if ((t_0 <= -5e+29) || !(t_0 <= -1.0)) {
		tmp = ((y - x) * -4.0) / z;
	} else {
		tmp = fma((x / z), 4.0, -2.0);
	}
	return tmp;
}
function code(x, y, z)
	t_0 = Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
	tmp = 0.0
	if ((t_0 <= -5e+29) || !(t_0 <= -1.0))
		tmp = Float64(Float64(Float64(y - x) * -4.0) / z);
	else
		tmp = fma(Float64(x / z), 4.0, -2.0);
	end
	return tmp
end
code[x_, y_, z_] := Block[{t$95$0 = N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]}, If[Or[LessEqual[t$95$0, -5e+29], N[Not[LessEqual[t$95$0, -1.0]], $MachinePrecision]], N[(N[(N[(y - x), $MachinePrecision] * -4.0), $MachinePrecision] / z), $MachinePrecision], N[(N[(x / z), $MachinePrecision] * 4.0 + -2.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\
\mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\
\;\;\;\;\frac{\left(y - x\right) \cdot -4}{z}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -5.0000000000000001e29 or -1 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z)

    1. Initial program 100.0%

      \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0

      \[\leadsto \frac{\color{blue}{4 \cdot \left(x - y\right)}}{z} \]
    4. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(-4\right)\right)} \cdot \left(x - y\right)}{z} \]
      2. distribute-lft-neg-inN/A

        \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(-4 \cdot \left(x - y\right)\right)}}{z} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\left(x - y\right) \cdot -4}\right)}{z} \]
      4. distribute-lft-neg-inN/A

        \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(\left(x - y\right)\right)\right) \cdot -4}}{z} \]
      5. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{\left(-1 \cdot \left(x - y\right)\right)} \cdot -4}{z} \]
      6. *-rgt-identityN/A

        \[\leadsto \frac{\color{blue}{\left(\left(-1 \cdot \left(x - y\right)\right) \cdot 1\right)} \cdot -4}{z} \]
      7. *-inversesN/A

        \[\leadsto \frac{\left(\left(-1 \cdot \left(x - y\right)\right) \cdot \color{blue}{\frac{z}{z}}\right) \cdot -4}{z} \]
      8. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(-1 \cdot \left(x - y\right)\right) \cdot z}{z}} \cdot -4}{z} \]
      9. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\left(\frac{-1 \cdot \left(x - y\right)}{z} \cdot z\right)} \cdot -4}{z} \]
      10. associate-*r/N/A

        \[\leadsto \frac{\left(\color{blue}{\left(-1 \cdot \frac{x - y}{z}\right)} \cdot z\right) \cdot -4}{z} \]
      11. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\left(z \cdot \left(-1 \cdot \frac{x - y}{z}\right)\right)} \cdot -4}{z} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\color{blue}{\left(z \cdot \left(-1 \cdot \frac{x - y}{z}\right)\right) \cdot -4}}{z} \]
      13. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\left(\left(-1 \cdot \frac{x - y}{z}\right) \cdot z\right)} \cdot -4}{z} \]
      14. associate-*r/N/A

        \[\leadsto \frac{\left(\color{blue}{\frac{-1 \cdot \left(x - y\right)}{z}} \cdot z\right) \cdot -4}{z} \]
      15. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(-1 \cdot \left(x - y\right)\right) \cdot z}{z}} \cdot -4}{z} \]
      16. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{\left(\left(-1 \cdot \left(x - y\right)\right) \cdot \frac{z}{z}\right)} \cdot -4}{z} \]
      17. *-inversesN/A

        \[\leadsto \frac{\left(\left(-1 \cdot \left(x - y\right)\right) \cdot \color{blue}{1}\right) \cdot -4}{z} \]
      18. *-rgt-identityN/A

        \[\leadsto \frac{\color{blue}{\left(-1 \cdot \left(x - y\right)\right)} \cdot -4}{z} \]
      19. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(\left(x - y\right)\right)\right)} \cdot -4}{z} \]
      20. neg-sub0N/A

        \[\leadsto \frac{\color{blue}{\left(0 - \left(x - y\right)\right)} \cdot -4}{z} \]
      21. associate-+l-N/A

        \[\leadsto \frac{\color{blue}{\left(\left(0 - x\right) + y\right)} \cdot -4}{z} \]
      22. neg-sub0N/A

        \[\leadsto \frac{\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)} + y\right) \cdot -4}{z} \]
      23. mul-1-negN/A

        \[\leadsto \frac{\left(\color{blue}{-1 \cdot x} + y\right) \cdot -4}{z} \]
      24. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\left(y + -1 \cdot x\right)} \cdot -4}{z} \]
      25. mul-1-negN/A

        \[\leadsto \frac{\left(y + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right) \cdot -4}{z} \]
      26. sub-negN/A

        \[\leadsto \frac{\color{blue}{\left(y - x\right)} \cdot -4}{z} \]
      27. lower--.f6499.4

        \[\leadsto \frac{\color{blue}{\left(y - x\right)} \cdot -4}{z} \]
    5. Applied rewrites99.4%

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

    if -5.0000000000000001e29 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -1

    1. Initial program 99.9%

      \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0

      \[\leadsto \color{blue}{4 \cdot \frac{x - \frac{1}{2} \cdot z}{z}} \]
    4. Step-by-step derivation
      1. div-subN/A

        \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} - \frac{\frac{1}{2} \cdot z}{z}\right)} \]
      2. sub-negN/A

        \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} + \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)\right)} \]
      3. distribute-lft-inN/A

        \[\leadsto \color{blue}{4 \cdot \frac{x}{z} + 4 \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)} \]
      4. *-lft-identityN/A

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

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

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

        \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2} \cdot \frac{z}{z}}\right)\right) \]
      8. *-inversesN/A

        \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\frac{1}{2} \cdot \color{blue}{1}\right)\right) \]
      9. metadata-evalN/A

        \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right) \]
      10. metadata-evalN/A

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

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(4 \cdot \frac{1}{z}, x, -2\right)} \]
      13. associate-*r/N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4 \cdot 1}{z}}, x, -2\right) \]
      14. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{4}}{z}, x, -2\right) \]
      15. lower-/.f6497.6

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4}{z}}, x, -2\right) \]
    5. Applied rewrites97.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{4}{z}, x, -2\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites97.7%

        \[\leadsto \mathsf{fma}\left(\frac{x}{z}, \color{blue}{4}, -2\right) \]
    7. Recombined 2 regimes into one program.
    8. Final simplification98.8%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -5 \cdot 10^{+29} \lor \neg \left(\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -1\right):\\ \;\;\;\;\frac{\left(y - x\right) \cdot -4}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \end{array} \]
    9. Add Preprocessing

    Alternative 3: 65.5% accurate, 0.3× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\ \mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \end{array} \]
    (FPCore (x y z)
     :precision binary64
     (let* ((t_0 (/ (* 4.0 (- (- x y) (* z 0.5))) z)))
       (if (or (<= t_0 -5e+29) (not (<= t_0 -1.0))) (/ (* -4.0 y) z) -2.0)))
    double code(double x, double y, double z) {
    	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
    	double tmp;
    	if ((t_0 <= -5e+29) || !(t_0 <= -1.0)) {
    		tmp = (-4.0 * y) / z;
    	} else {
    		tmp = -2.0;
    	}
    	return tmp;
    }
    
    real(8) function code(x, y, z)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8) :: t_0
        real(8) :: tmp
        t_0 = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
        if ((t_0 <= (-5d+29)) .or. (.not. (t_0 <= (-1.0d0)))) then
            tmp = ((-4.0d0) * y) / z
        else
            tmp = -2.0d0
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z) {
    	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
    	double tmp;
    	if ((t_0 <= -5e+29) || !(t_0 <= -1.0)) {
    		tmp = (-4.0 * y) / z;
    	} else {
    		tmp = -2.0;
    	}
    	return tmp;
    }
    
    def code(x, y, z):
    	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z
    	tmp = 0
    	if (t_0 <= -5e+29) or not (t_0 <= -1.0):
    		tmp = (-4.0 * y) / z
    	else:
    		tmp = -2.0
    	return tmp
    
    function code(x, y, z)
    	t_0 = Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
    	tmp = 0.0
    	if ((t_0 <= -5e+29) || !(t_0 <= -1.0))
    		tmp = Float64(Float64(-4.0 * y) / z);
    	else
    		tmp = -2.0;
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z)
    	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
    	tmp = 0.0;
    	if ((t_0 <= -5e+29) || ~((t_0 <= -1.0)))
    		tmp = (-4.0 * y) / z;
    	else
    		tmp = -2.0;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_] := Block[{t$95$0 = N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]}, If[Or[LessEqual[t$95$0, -5e+29], N[Not[LessEqual[t$95$0, -1.0]], $MachinePrecision]], N[(N[(-4.0 * y), $MachinePrecision] / z), $MachinePrecision], -2.0]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\
    \mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\
    \;\;\;\;\frac{-4 \cdot y}{z}\\
    
    \mathbf{else}:\\
    \;\;\;\;-2\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -5.0000000000000001e29 or -1 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z)

      1. Initial program 100.0%

        \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
      2. Add Preprocessing
      3. Taylor expanded in y around inf

        \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
      4. Step-by-step derivation
        1. lower-*.f6455.0

          \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
      5. Applied rewrites55.0%

        \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]

      if -5.0000000000000001e29 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -1

      1. Initial program 99.9%

        \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
      2. Add Preprocessing
      3. Taylor expanded in z around inf

        \[\leadsto \color{blue}{-2} \]
      4. Step-by-step derivation
        1. Applied rewrites90.2%

          \[\leadsto \color{blue}{-2} \]
      5. Recombined 2 regimes into one program.
      6. Final simplification66.7%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -5 \cdot 10^{+29} \lor \neg \left(\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -1\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \]
      7. Add Preprocessing

      Alternative 4: 65.5% accurate, 0.3× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\ \mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\ \;\;\;\;\frac{-4}{z} \cdot y\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \end{array} \]
      (FPCore (x y z)
       :precision binary64
       (let* ((t_0 (/ (* 4.0 (- (- x y) (* z 0.5))) z)))
         (if (or (<= t_0 -5e+29) (not (<= t_0 -1.0))) (* (/ -4.0 z) y) -2.0)))
      double code(double x, double y, double z) {
      	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
      	double tmp;
      	if ((t_0 <= -5e+29) || !(t_0 <= -1.0)) {
      		tmp = (-4.0 / z) * y;
      	} else {
      		tmp = -2.0;
      	}
      	return tmp;
      }
      
      real(8) function code(x, y, z)
          real(8), intent (in) :: x
          real(8), intent (in) :: y
          real(8), intent (in) :: z
          real(8) :: t_0
          real(8) :: tmp
          t_0 = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
          if ((t_0 <= (-5d+29)) .or. (.not. (t_0 <= (-1.0d0)))) then
              tmp = ((-4.0d0) / z) * y
          else
              tmp = -2.0d0
          end if
          code = tmp
      end function
      
      public static double code(double x, double y, double z) {
      	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
      	double tmp;
      	if ((t_0 <= -5e+29) || !(t_0 <= -1.0)) {
      		tmp = (-4.0 / z) * y;
      	} else {
      		tmp = -2.0;
      	}
      	return tmp;
      }
      
      def code(x, y, z):
      	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z
      	tmp = 0
      	if (t_0 <= -5e+29) or not (t_0 <= -1.0):
      		tmp = (-4.0 / z) * y
      	else:
      		tmp = -2.0
      	return tmp
      
      function code(x, y, z)
      	t_0 = Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
      	tmp = 0.0
      	if ((t_0 <= -5e+29) || !(t_0 <= -1.0))
      		tmp = Float64(Float64(-4.0 / z) * y);
      	else
      		tmp = -2.0;
      	end
      	return tmp
      end
      
      function tmp_2 = code(x, y, z)
      	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
      	tmp = 0.0;
      	if ((t_0 <= -5e+29) || ~((t_0 <= -1.0)))
      		tmp = (-4.0 / z) * y;
      	else
      		tmp = -2.0;
      	end
      	tmp_2 = tmp;
      end
      
      code[x_, y_, z_] := Block[{t$95$0 = N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]}, If[Or[LessEqual[t$95$0, -5e+29], N[Not[LessEqual[t$95$0, -1.0]], $MachinePrecision]], N[(N[(-4.0 / z), $MachinePrecision] * y), $MachinePrecision], -2.0]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\
      \mathbf{if}\;t\_0 \leq -5 \cdot 10^{+29} \lor \neg \left(t\_0 \leq -1\right):\\
      \;\;\;\;\frac{-4}{z} \cdot y\\
      
      \mathbf{else}:\\
      \;\;\;\;-2\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -5.0000000000000001e29 or -1 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z)

        1. Initial program 100.0%

          \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
        2. Add Preprocessing
        3. Taylor expanded in y around inf

          \[\leadsto \color{blue}{-4 \cdot \frac{y}{z}} \]
        4. Step-by-step derivation
          1. *-lft-identityN/A

            \[\leadsto -4 \cdot \frac{\color{blue}{1 \cdot y}}{z} \]
          2. associate-*l/N/A

            \[\leadsto -4 \cdot \color{blue}{\left(\frac{1}{z} \cdot y\right)} \]
          3. associate-*l*N/A

            \[\leadsto \color{blue}{\left(-4 \cdot \frac{1}{z}\right) \cdot y} \]
          4. metadata-evalN/A

            \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(4\right)\right)} \cdot \frac{1}{z}\right) \cdot y \]
          5. distribute-lft-neg-inN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(4 \cdot \frac{1}{z}\right)\right)} \cdot y \]
          6. lower-*.f64N/A

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

            \[\leadsto \left(\mathsf{neg}\left(\color{blue}{\frac{4 \cdot 1}{z}}\right)\right) \cdot y \]
          8. metadata-evalN/A

            \[\leadsto \left(\mathsf{neg}\left(\frac{\color{blue}{4}}{z}\right)\right) \cdot y \]
          9. distribute-neg-fracN/A

            \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(4\right)}{z}} \cdot y \]
          10. metadata-evalN/A

            \[\leadsto \frac{\color{blue}{-4}}{z} \cdot y \]
          11. lower-/.f6454.8

            \[\leadsto \color{blue}{\frac{-4}{z}} \cdot y \]
        5. Applied rewrites54.8%

          \[\leadsto \color{blue}{\frac{-4}{z} \cdot y} \]

        if -5.0000000000000001e29 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -1

        1. Initial program 99.9%

          \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
        2. Add Preprocessing
        3. Taylor expanded in z around inf

          \[\leadsto \color{blue}{-2} \]
        4. Step-by-step derivation
          1. Applied rewrites90.2%

            \[\leadsto \color{blue}{-2} \]
        5. Recombined 2 regimes into one program.
        6. Final simplification66.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -5 \cdot 10^{+29} \lor \neg \left(\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -1\right):\\ \;\;\;\;\frac{-4}{z} \cdot y\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \]
        7. Add Preprocessing

        Alternative 5: 67.5% accurate, 0.3× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\ \mathbf{if}\;t\_0 \leq -500000 \lor \neg \left(t\_0 \leq -1\right):\\ \;\;\;\;\frac{4}{z} \cdot x\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \end{array} \]
        (FPCore (x y z)
         :precision binary64
         (let* ((t_0 (/ (* 4.0 (- (- x y) (* z 0.5))) z)))
           (if (or (<= t_0 -500000.0) (not (<= t_0 -1.0))) (* (/ 4.0 z) x) -2.0)))
        double code(double x, double y, double z) {
        	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
        	double tmp;
        	if ((t_0 <= -500000.0) || !(t_0 <= -1.0)) {
        		tmp = (4.0 / z) * x;
        	} else {
        		tmp = -2.0;
        	}
        	return tmp;
        }
        
        real(8) function code(x, y, z)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            real(8), intent (in) :: z
            real(8) :: t_0
            real(8) :: tmp
            t_0 = (4.0d0 * ((x - y) - (z * 0.5d0))) / z
            if ((t_0 <= (-500000.0d0)) .or. (.not. (t_0 <= (-1.0d0)))) then
                tmp = (4.0d0 / z) * x
            else
                tmp = -2.0d0
            end if
            code = tmp
        end function
        
        public static double code(double x, double y, double z) {
        	double t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
        	double tmp;
        	if ((t_0 <= -500000.0) || !(t_0 <= -1.0)) {
        		tmp = (4.0 / z) * x;
        	} else {
        		tmp = -2.0;
        	}
        	return tmp;
        }
        
        def code(x, y, z):
        	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z
        	tmp = 0
        	if (t_0 <= -500000.0) or not (t_0 <= -1.0):
        		tmp = (4.0 / z) * x
        	else:
        		tmp = -2.0
        	return tmp
        
        function code(x, y, z)
        	t_0 = Float64(Float64(4.0 * Float64(Float64(x - y) - Float64(z * 0.5))) / z)
        	tmp = 0.0
        	if ((t_0 <= -500000.0) || !(t_0 <= -1.0))
        		tmp = Float64(Float64(4.0 / z) * x);
        	else
        		tmp = -2.0;
        	end
        	return tmp
        end
        
        function tmp_2 = code(x, y, z)
        	t_0 = (4.0 * ((x - y) - (z * 0.5))) / z;
        	tmp = 0.0;
        	if ((t_0 <= -500000.0) || ~((t_0 <= -1.0)))
        		tmp = (4.0 / z) * x;
        	else
        		tmp = -2.0;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_, y_, z_] := Block[{t$95$0 = N[(N[(4.0 * N[(N[(x - y), $MachinePrecision] - N[(z * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / z), $MachinePrecision]}, If[Or[LessEqual[t$95$0, -500000.0], N[Not[LessEqual[t$95$0, -1.0]], $MachinePrecision]], N[(N[(4.0 / z), $MachinePrecision] * x), $MachinePrecision], -2.0]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_0 := \frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z}\\
        \mathbf{if}\;t\_0 \leq -500000 \lor \neg \left(t\_0 \leq -1\right):\\
        \;\;\;\;\frac{4}{z} \cdot x\\
        
        \mathbf{else}:\\
        \;\;\;\;-2\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -5e5 or -1 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z)

          1. Initial program 100.0%

            \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-/.f64N/A

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

              \[\leadsto \frac{\color{blue}{4 \cdot \left(\left(x - y\right) - z \cdot \frac{1}{2}\right)}}{z} \]
            3. *-commutativeN/A

              \[\leadsto \frac{\color{blue}{\left(\left(x - y\right) - z \cdot \frac{1}{2}\right) \cdot 4}}{z} \]
            4. associate-/l*N/A

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

              \[\leadsto \color{blue}{\left(\left(x - y\right) - z \cdot \frac{1}{2}\right)} \cdot \frac{4}{z} \]
            6. flip--N/A

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

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

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

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

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

              \[\leadsto \frac{4}{\color{blue}{\frac{\left(x - y\right) + z \cdot \frac{1}{2}}{\left(x - y\right) \cdot \left(x - y\right) - \left(z \cdot \frac{1}{2}\right) \cdot \left(z \cdot \frac{1}{2}\right)} \cdot z}} \]
          4. Applied rewrites99.6%

            \[\leadsto \color{blue}{\frac{4}{\frac{1}{\mathsf{fma}\left(-0.5, z, x - y\right)} \cdot z}} \]
          5. Taylor expanded in x around inf

            \[\leadsto \color{blue}{4 \cdot \frac{x}{z}} \]
          6. Step-by-step derivation
            1. associate-*r/N/A

              \[\leadsto \color{blue}{\frac{4 \cdot x}{z}} \]
            2. associate-*l/N/A

              \[\leadsto \color{blue}{\frac{4}{z} \cdot x} \]
            3. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{4 \cdot 1}}{z} \cdot x \]
            4. associate-*r/N/A

              \[\leadsto \color{blue}{\left(4 \cdot \frac{1}{z}\right)} \cdot x \]
            5. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(4 \cdot \frac{1}{z}\right) \cdot x} \]
            6. associate-*r/N/A

              \[\leadsto \color{blue}{\frac{4 \cdot 1}{z}} \cdot x \]
            7. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{4}}{z} \cdot x \]
            8. lower-/.f6450.9

              \[\leadsto \color{blue}{\frac{4}{z}} \cdot x \]
          7. Applied rewrites50.9%

            \[\leadsto \color{blue}{\frac{4}{z} \cdot x} \]

          if -5e5 < (/.f64 (*.f64 #s(literal 4 binary64) (-.f64 (-.f64 x y) (*.f64 z #s(literal 1/2 binary64)))) z) < -1

          1. Initial program 99.9%

            \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
          2. Add Preprocessing
          3. Taylor expanded in z around inf

            \[\leadsto \color{blue}{-2} \]
          4. Step-by-step derivation
            1. Applied rewrites94.1%

              \[\leadsto \color{blue}{-2} \]
          5. Recombined 2 regimes into one program.
          6. Final simplification64.6%

            \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -500000 \lor \neg \left(\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \leq -1\right):\\ \;\;\;\;\frac{4}{z} \cdot x\\ \mathbf{else}:\\ \;\;\;\;-2\\ \end{array} \]
          7. Add Preprocessing

          Alternative 6: 86.6% accurate, 0.9× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5.8 \cdot 10^{-8} \lor \neg \left(x \leq 1.22 \cdot 10^{+85}\right):\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, -4, -2\right)\\ \end{array} \end{array} \]
          (FPCore (x y z)
           :precision binary64
           (if (or (<= x -5.8e-8) (not (<= x 1.22e+85)))
             (fma (/ x z) 4.0 -2.0)
             (fma (/ y z) -4.0 -2.0)))
          double code(double x, double y, double z) {
          	double tmp;
          	if ((x <= -5.8e-8) || !(x <= 1.22e+85)) {
          		tmp = fma((x / z), 4.0, -2.0);
          	} else {
          		tmp = fma((y / z), -4.0, -2.0);
          	}
          	return tmp;
          }
          
          function code(x, y, z)
          	tmp = 0.0
          	if ((x <= -5.8e-8) || !(x <= 1.22e+85))
          		tmp = fma(Float64(x / z), 4.0, -2.0);
          	else
          		tmp = fma(Float64(y / z), -4.0, -2.0);
          	end
          	return tmp
          end
          
          code[x_, y_, z_] := If[Or[LessEqual[x, -5.8e-8], N[Not[LessEqual[x, 1.22e+85]], $MachinePrecision]], N[(N[(x / z), $MachinePrecision] * 4.0 + -2.0), $MachinePrecision], N[(N[(y / z), $MachinePrecision] * -4.0 + -2.0), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;x \leq -5.8 \cdot 10^{-8} \lor \neg \left(x \leq 1.22 \cdot 10^{+85}\right):\\
          \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, -4, -2\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if x < -5.8000000000000003e-8 or 1.22e85 < x

            1. Initial program 100.0%

              \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto \color{blue}{4 \cdot \frac{x - \frac{1}{2} \cdot z}{z}} \]
            4. Step-by-step derivation
              1. div-subN/A

                \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} - \frac{\frac{1}{2} \cdot z}{z}\right)} \]
              2. sub-negN/A

                \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} + \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)\right)} \]
              3. distribute-lft-inN/A

                \[\leadsto \color{blue}{4 \cdot \frac{x}{z} + 4 \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)} \]
              4. *-lft-identityN/A

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

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

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

                \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2} \cdot \frac{z}{z}}\right)\right) \]
              8. *-inversesN/A

                \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\frac{1}{2} \cdot \color{blue}{1}\right)\right) \]
              9. metadata-evalN/A

                \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right) \]
              10. metadata-evalN/A

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

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

                \[\leadsto \color{blue}{\mathsf{fma}\left(4 \cdot \frac{1}{z}, x, -2\right)} \]
              13. associate-*r/N/A

                \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4 \cdot 1}{z}}, x, -2\right) \]
              14. metadata-evalN/A

                \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{4}}{z}, x, -2\right) \]
              15. lower-/.f6487.1

                \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4}{z}}, x, -2\right) \]
            5. Applied rewrites87.1%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{4}{z}, x, -2\right)} \]
            6. Step-by-step derivation
              1. Applied rewrites87.2%

                \[\leadsto \mathsf{fma}\left(\frac{x}{z}, \color{blue}{4}, -2\right) \]

              if -5.8000000000000003e-8 < x < 1.22e85

              1. Initial program 99.9%

                \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
              2. Add Preprocessing
              3. Taylor expanded in z around inf

                \[\leadsto \color{blue}{-2} \]
              4. Step-by-step derivation
                1. Applied rewrites42.2%

                  \[\leadsto \color{blue}{-2} \]
                2. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{-4 \cdot \frac{y + \frac{1}{2} \cdot z}{z}} \]
                3. Step-by-step derivation
                  1. metadata-evalN/A

                    \[\leadsto -4 \cdot \frac{y + \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot z}{z} \]
                  2. cancel-sign-sub-invN/A

                    \[\leadsto -4 \cdot \frac{\color{blue}{y - \frac{-1}{2} \cdot z}}{z} \]
                  3. div-subN/A

                    \[\leadsto -4 \cdot \color{blue}{\left(\frac{y}{z} - \frac{\frac{-1}{2} \cdot z}{z}\right)} \]
                  4. sub-negN/A

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

                    \[\leadsto -4 \cdot \left(\frac{y}{z} + \left(\mathsf{neg}\left(\color{blue}{\frac{-1}{2} \cdot \frac{z}{z}}\right)\right)\right) \]
                  6. *-inversesN/A

                    \[\leadsto -4 \cdot \left(\frac{y}{z} + \left(\mathsf{neg}\left(\frac{-1}{2} \cdot \color{blue}{1}\right)\right)\right) \]
                  7. metadata-evalN/A

                    \[\leadsto -4 \cdot \left(\frac{y}{z} + \left(\mathsf{neg}\left(\color{blue}{\frac{-1}{2}}\right)\right)\right) \]
                  8. metadata-evalN/A

                    \[\leadsto -4 \cdot \left(\frac{y}{z} + \color{blue}{\frac{1}{2}}\right) \]
                  9. distribute-rgt-inN/A

                    \[\leadsto \color{blue}{\frac{y}{z} \cdot -4 + \frac{1}{2} \cdot -4} \]
                  10. metadata-evalN/A

                    \[\leadsto \frac{y}{z} \cdot -4 + \color{blue}{-2} \]
                  11. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, -4, -2\right)} \]
                  12. lower-/.f6491.2

                    \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{z}}, -4, -2\right) \]
                4. Applied rewrites91.2%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, -4, -2\right)} \]
              5. Recombined 2 regimes into one program.
              6. Final simplification89.5%

                \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5.8 \cdot 10^{-8} \lor \neg \left(x \leq 1.22 \cdot 10^{+85}\right):\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, -4, -2\right)\\ \end{array} \]
              7. Add Preprocessing

              Alternative 7: 80.6% accurate, 0.9× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \end{array} \end{array} \]
              (FPCore (x y z)
               :precision binary64
               (if (or (<= y -6.6e+118) (not (<= y 7.5e+168)))
                 (/ (* -4.0 y) z)
                 (fma (/ x z) 4.0 -2.0)))
              double code(double x, double y, double z) {
              	double tmp;
              	if ((y <= -6.6e+118) || !(y <= 7.5e+168)) {
              		tmp = (-4.0 * y) / z;
              	} else {
              		tmp = fma((x / z), 4.0, -2.0);
              	}
              	return tmp;
              }
              
              function code(x, y, z)
              	tmp = 0.0
              	if ((y <= -6.6e+118) || !(y <= 7.5e+168))
              		tmp = Float64(Float64(-4.0 * y) / z);
              	else
              		tmp = fma(Float64(x / z), 4.0, -2.0);
              	end
              	return tmp
              end
              
              code[x_, y_, z_] := If[Or[LessEqual[y, -6.6e+118], N[Not[LessEqual[y, 7.5e+168]], $MachinePrecision]], N[(N[(-4.0 * y), $MachinePrecision] / z), $MachinePrecision], N[(N[(x / z), $MachinePrecision] * 4.0 + -2.0), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\
              \;\;\;\;\frac{-4 \cdot y}{z}\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if y < -6.6e118 or 7.4999999999999999e168 < y

                1. Initial program 99.9%

                  \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
                2. Add Preprocessing
                3. Taylor expanded in y around inf

                  \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
                4. Step-by-step derivation
                  1. lower-*.f6479.2

                    \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
                5. Applied rewrites79.2%

                  \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]

                if -6.6e118 < y < 7.4999999999999999e168

                1. Initial program 100.0%

                  \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{4 \cdot \frac{x - \frac{1}{2} \cdot z}{z}} \]
                4. Step-by-step derivation
                  1. div-subN/A

                    \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} - \frac{\frac{1}{2} \cdot z}{z}\right)} \]
                  2. sub-negN/A

                    \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} + \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)\right)} \]
                  3. distribute-lft-inN/A

                    \[\leadsto \color{blue}{4 \cdot \frac{x}{z} + 4 \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)} \]
                  4. *-lft-identityN/A

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

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

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

                    \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2} \cdot \frac{z}{z}}\right)\right) \]
                  8. *-inversesN/A

                    \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\frac{1}{2} \cdot \color{blue}{1}\right)\right) \]
                  9. metadata-evalN/A

                    \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right) \]
                  10. metadata-evalN/A

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

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

                    \[\leadsto \color{blue}{\mathsf{fma}\left(4 \cdot \frac{1}{z}, x, -2\right)} \]
                  13. associate-*r/N/A

                    \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4 \cdot 1}{z}}, x, -2\right) \]
                  14. metadata-evalN/A

                    \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{4}}{z}, x, -2\right) \]
                  15. lower-/.f6479.8

                    \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4}{z}}, x, -2\right) \]
                5. Applied rewrites79.8%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{4}{z}, x, -2\right)} \]
                6. Step-by-step derivation
                  1. Applied rewrites79.9%

                    \[\leadsto \mathsf{fma}\left(\frac{x}{z}, \color{blue}{4}, -2\right) \]
                7. Recombined 2 regimes into one program.
                8. Final simplification79.7%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{z}, 4, -2\right)\\ \end{array} \]
                9. Add Preprocessing

                Alternative 8: 80.5% accurate, 0.9× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{4}{z}, x, -2\right)\\ \end{array} \end{array} \]
                (FPCore (x y z)
                 :precision binary64
                 (if (or (<= y -6.6e+118) (not (<= y 7.5e+168)))
                   (/ (* -4.0 y) z)
                   (fma (/ 4.0 z) x -2.0)))
                double code(double x, double y, double z) {
                	double tmp;
                	if ((y <= -6.6e+118) || !(y <= 7.5e+168)) {
                		tmp = (-4.0 * y) / z;
                	} else {
                		tmp = fma((4.0 / z), x, -2.0);
                	}
                	return tmp;
                }
                
                function code(x, y, z)
                	tmp = 0.0
                	if ((y <= -6.6e+118) || !(y <= 7.5e+168))
                		tmp = Float64(Float64(-4.0 * y) / z);
                	else
                		tmp = fma(Float64(4.0 / z), x, -2.0);
                	end
                	return tmp
                end
                
                code[x_, y_, z_] := If[Or[LessEqual[y, -6.6e+118], N[Not[LessEqual[y, 7.5e+168]], $MachinePrecision]], N[(N[(-4.0 * y), $MachinePrecision] / z), $MachinePrecision], N[(N[(4.0 / z), $MachinePrecision] * x + -2.0), $MachinePrecision]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\
                \;\;\;\;\frac{-4 \cdot y}{z}\\
                
                \mathbf{else}:\\
                \;\;\;\;\mathsf{fma}\left(\frac{4}{z}, x, -2\right)\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if y < -6.6e118 or 7.4999999999999999e168 < y

                  1. Initial program 99.9%

                    \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
                  2. Add Preprocessing
                  3. Taylor expanded in y around inf

                    \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
                  4. Step-by-step derivation
                    1. lower-*.f6479.2

                      \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]
                  5. Applied rewrites79.2%

                    \[\leadsto \frac{\color{blue}{-4 \cdot y}}{z} \]

                  if -6.6e118 < y < 7.4999999999999999e168

                  1. Initial program 100.0%

                    \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
                  2. Add Preprocessing
                  3. Taylor expanded in y around 0

                    \[\leadsto \color{blue}{4 \cdot \frac{x - \frac{1}{2} \cdot z}{z}} \]
                  4. Step-by-step derivation
                    1. div-subN/A

                      \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} - \frac{\frac{1}{2} \cdot z}{z}\right)} \]
                    2. sub-negN/A

                      \[\leadsto 4 \cdot \color{blue}{\left(\frac{x}{z} + \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)\right)} \]
                    3. distribute-lft-inN/A

                      \[\leadsto \color{blue}{4 \cdot \frac{x}{z} + 4 \cdot \left(\mathsf{neg}\left(\frac{\frac{1}{2} \cdot z}{z}\right)\right)} \]
                    4. *-lft-identityN/A

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

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

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

                      \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2} \cdot \frac{z}{z}}\right)\right) \]
                    8. *-inversesN/A

                      \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\frac{1}{2} \cdot \color{blue}{1}\right)\right) \]
                    9. metadata-evalN/A

                      \[\leadsto \left(4 \cdot \frac{1}{z}\right) \cdot x + 4 \cdot \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right) \]
                    10. metadata-evalN/A

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

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

                      \[\leadsto \color{blue}{\mathsf{fma}\left(4 \cdot \frac{1}{z}, x, -2\right)} \]
                    13. associate-*r/N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4 \cdot 1}{z}}, x, -2\right) \]
                    14. metadata-evalN/A

                      \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{4}}{z}, x, -2\right) \]
                    15. lower-/.f6479.8

                      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{4}{z}}, x, -2\right) \]
                  5. Applied rewrites79.8%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{4}{z}, x, -2\right)} \]
                3. Recombined 2 regimes into one program.
                4. Final simplification79.7%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -6.6 \cdot 10^{+118} \lor \neg \left(y \leq 7.5 \cdot 10^{+168}\right):\\ \;\;\;\;\frac{-4 \cdot y}{z}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{4}{z}, x, -2\right)\\ \end{array} \]
                5. Add Preprocessing

                Alternative 9: 34.7% accurate, 28.0× speedup?

                \[\begin{array}{l} \\ -2 \end{array} \]
                (FPCore (x y z) :precision binary64 -2.0)
                double code(double x, double y, double z) {
                	return -2.0;
                }
                
                real(8) function code(x, y, z)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    code = -2.0d0
                end function
                
                public static double code(double x, double y, double z) {
                	return -2.0;
                }
                
                def code(x, y, z):
                	return -2.0
                
                function code(x, y, z)
                	return -2.0
                end
                
                function tmp = code(x, y, z)
                	tmp = -2.0;
                end
                
                code[x_, y_, z_] := -2.0
                
                \begin{array}{l}
                
                \\
                -2
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\frac{4 \cdot \left(\left(x - y\right) - z \cdot 0.5\right)}{z} \]
                2. Add Preprocessing
                3. Taylor expanded in z around inf

                  \[\leadsto \color{blue}{-2} \]
                4. Step-by-step derivation
                  1. Applied rewrites31.6%

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

                  Developer Target 1: 98.0% accurate, 0.7× speedup?

                  \[\begin{array}{l} \\ 4 \cdot \frac{x}{z} - \left(2 + 4 \cdot \frac{y}{z}\right) \end{array} \]
                  (FPCore (x y z)
                   :precision binary64
                   (- (* 4.0 (/ x z)) (+ 2.0 (* 4.0 (/ y z)))))
                  double code(double x, double y, double z) {
                  	return (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)));
                  }
                  
                  real(8) function code(x, y, z)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      real(8), intent (in) :: z
                      code = (4.0d0 * (x / z)) - (2.0d0 + (4.0d0 * (y / z)))
                  end function
                  
                  public static double code(double x, double y, double z) {
                  	return (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)));
                  }
                  
                  def code(x, y, z):
                  	return (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)))
                  
                  function code(x, y, z)
                  	return Float64(Float64(4.0 * Float64(x / z)) - Float64(2.0 + Float64(4.0 * Float64(y / z))))
                  end
                  
                  function tmp = code(x, y, z)
                  	tmp = (4.0 * (x / z)) - (2.0 + (4.0 * (y / z)));
                  end
                  
                  code[x_, y_, z_] := N[(N[(4.0 * N[(x / z), $MachinePrecision]), $MachinePrecision] - N[(2.0 + N[(4.0 * N[(y / z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  4 \cdot \frac{x}{z} - \left(2 + 4 \cdot \frac{y}{z}\right)
                  \end{array}
                  

                  Reproduce

                  ?
                  herbie shell --seed 2024340 
                  (FPCore (x y z)
                    :name "Data.Array.Repa.Algorithms.ColorRamp:rampColorHotToCold from repa-algorithms-3.4.0.1, B"
                    :precision binary64
                  
                    :alt
                    (! :herbie-platform default (- (* 4 (/ x z)) (+ 2 (* 4 (/ y z)))))
                  
                    (/ (* 4.0 (- (- x y) (* z 0.5))) z))