Numeric.SpecFunctions:choose from math-functions-0.1.5.2

Percentage Accurate: 84.8% → 96.2%
Time: 4.8s
Alternatives: 5
Speedup: 0.8×

Specification

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

\\
\frac{x \cdot \left(y + z\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 5 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: 84.8% accurate, 1.0× speedup?

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

\\
\frac{x \cdot \left(y + z\right)}{z}
\end{array}

Alternative 1: 96.2% accurate, 0.4× speedup?

\[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;\frac{\left(y + z\right) \cdot x\_m}{z} \leq -1 \cdot 10^{+166}:\\ \;\;\;\;\frac{y}{\frac{z}{x\_m}}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x\_m, x\_m\right)\\ \end{array} \end{array} \]
x\_m = (fabs.f64 x)
x\_s = (copysign.f64 #s(literal 1 binary64) x)
(FPCore (x_s x_m y z)
 :precision binary64
 (*
  x_s
  (if (<= (/ (* (+ y z) x_m) z) -1e+166)
    (/ y (/ z x_m))
    (fma (/ y z) x_m x_m))))
x\_m = fabs(x);
x\_s = copysign(1.0, x);
double code(double x_s, double x_m, double y, double z) {
	double tmp;
	if ((((y + z) * x_m) / z) <= -1e+166) {
		tmp = y / (z / x_m);
	} else {
		tmp = fma((y / z), x_m, x_m);
	}
	return x_s * tmp;
}
x\_m = abs(x)
x\_s = copysign(1.0, x)
function code(x_s, x_m, y, z)
	tmp = 0.0
	if (Float64(Float64(Float64(y + z) * x_m) / z) <= -1e+166)
		tmp = Float64(y / Float64(z / x_m));
	else
		tmp = fma(Float64(y / z), x_m, x_m);
	end
	return Float64(x_s * tmp)
end
x\_m = N[Abs[x], $MachinePrecision]
x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * If[LessEqual[N[(N[(N[(y + z), $MachinePrecision] * x$95$m), $MachinePrecision] / z), $MachinePrecision], -1e+166], N[(y / N[(z / x$95$m), $MachinePrecision]), $MachinePrecision], N[(N[(y / z), $MachinePrecision] * x$95$m + x$95$m), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
x\_m = \left|x\right|
\\
x\_s = \mathsf{copysign}\left(1, x\right)

\\
x\_s \cdot \begin{array}{l}
\mathbf{if}\;\frac{\left(y + z\right) \cdot x\_m}{z} \leq -1 \cdot 10^{+166}:\\
\;\;\;\;\frac{y}{\frac{z}{x\_m}}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x\_m, x\_m\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (*.f64 x (+.f64 y z)) z) < -9.9999999999999994e165

    1. Initial program 69.0%

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

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

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

        \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
      4. clear-numN/A

        \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
      7. lower-/.f6490.2

        \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
      8. lift-+.f64N/A

        \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
      9. +-commutativeN/A

        \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
      10. lower-+.f6490.2

        \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
    4. Applied rewrites90.2%

      \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
    5. Taylor expanded in y around inf

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

        \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
      2. lower-*.f64N/A

        \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
      3. lower-/.f6465.7

        \[\leadsto \color{blue}{\frac{x}{z}} \cdot y \]
    7. Applied rewrites65.7%

      \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
    8. Step-by-step derivation
      1. Applied rewrites65.7%

        \[\leadsto \frac{y}{\color{blue}{\frac{z}{x}}} \]

      if -9.9999999999999994e165 < (/.f64 (*.f64 x (+.f64 y z)) z)

      1. Initial program 84.2%

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

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

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

          \[\leadsto \color{blue}{\frac{y + z}{z} \cdot x} \]
        3. +-commutativeN/A

          \[\leadsto \frac{\color{blue}{z + y}}{z} \cdot x \]
        4. *-lft-identityN/A

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

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

          \[\leadsto \frac{\color{blue}{z - -1 \cdot y}}{z} \cdot x \]
        7. div-subN/A

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

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

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

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

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

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

          \[\leadsto \color{blue}{\left(\frac{y}{z} + 1\right)} \cdot x \]
        14. distribute-lft1-inN/A

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

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, x, x\right)} \]
        16. lower-/.f6496.8

          \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{z}}, x, x\right) \]
      5. Applied rewrites96.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, x, x\right)} \]
    9. Recombined 2 regimes into one program.
    10. Final simplification91.0%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\left(y + z\right) \cdot x}{z} \leq -1 \cdot 10^{+166}:\\ \;\;\;\;\frac{y}{\frac{z}{x}}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x, x\right)\\ \end{array} \]
    11. Add Preprocessing

    Alternative 2: 96.1% accurate, 0.5× speedup?

    \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;\frac{\left(y + z\right) \cdot x\_m}{z} \leq -1 \cdot 10^{+166}:\\ \;\;\;\;\frac{x\_m}{z} \cdot y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x\_m, x\_m\right)\\ \end{array} \end{array} \]
    x\_m = (fabs.f64 x)
    x\_s = (copysign.f64 #s(literal 1 binary64) x)
    (FPCore (x_s x_m y z)
     :precision binary64
     (*
      x_s
      (if (<= (/ (* (+ y z) x_m) z) -1e+166)
        (* (/ x_m z) y)
        (fma (/ y z) x_m x_m))))
    x\_m = fabs(x);
    x\_s = copysign(1.0, x);
    double code(double x_s, double x_m, double y, double z) {
    	double tmp;
    	if ((((y + z) * x_m) / z) <= -1e+166) {
    		tmp = (x_m / z) * y;
    	} else {
    		tmp = fma((y / z), x_m, x_m);
    	}
    	return x_s * tmp;
    }
    
    x\_m = abs(x)
    x\_s = copysign(1.0, x)
    function code(x_s, x_m, y, z)
    	tmp = 0.0
    	if (Float64(Float64(Float64(y + z) * x_m) / z) <= -1e+166)
    		tmp = Float64(Float64(x_m / z) * y);
    	else
    		tmp = fma(Float64(y / z), x_m, x_m);
    	end
    	return Float64(x_s * tmp)
    end
    
    x\_m = N[Abs[x], $MachinePrecision]
    x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * If[LessEqual[N[(N[(N[(y + z), $MachinePrecision] * x$95$m), $MachinePrecision] / z), $MachinePrecision], -1e+166], N[(N[(x$95$m / z), $MachinePrecision] * y), $MachinePrecision], N[(N[(y / z), $MachinePrecision] * x$95$m + x$95$m), $MachinePrecision]]), $MachinePrecision]
    
    \begin{array}{l}
    x\_m = \left|x\right|
    \\
    x\_s = \mathsf{copysign}\left(1, x\right)
    
    \\
    x\_s \cdot \begin{array}{l}
    \mathbf{if}\;\frac{\left(y + z\right) \cdot x\_m}{z} \leq -1 \cdot 10^{+166}:\\
    \;\;\;\;\frac{x\_m}{z} \cdot y\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x\_m, x\_m\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (*.f64 x (+.f64 y z)) z) < -9.9999999999999994e165

      1. Initial program 69.0%

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

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

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

          \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
        4. clear-numN/A

          \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
        5. un-div-invN/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        6. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        7. lower-/.f6490.2

          \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
        8. lift-+.f64N/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
        9. +-commutativeN/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
        10. lower-+.f6490.2

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
      4. Applied rewrites90.2%

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
      5. Taylor expanded in y around inf

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

          \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
        2. lower-*.f64N/A

          \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
        3. lower-/.f6465.7

          \[\leadsto \color{blue}{\frac{x}{z}} \cdot y \]
      7. Applied rewrites65.7%

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

      if -9.9999999999999994e165 < (/.f64 (*.f64 x (+.f64 y z)) z)

      1. Initial program 84.2%

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

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

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

          \[\leadsto \color{blue}{\frac{y + z}{z} \cdot x} \]
        3. +-commutativeN/A

          \[\leadsto \frac{\color{blue}{z + y}}{z} \cdot x \]
        4. *-lft-identityN/A

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

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

          \[\leadsto \frac{\color{blue}{z - -1 \cdot y}}{z} \cdot x \]
        7. div-subN/A

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

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

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

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

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

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

          \[\leadsto \color{blue}{\left(\frac{y}{z} + 1\right)} \cdot x \]
        14. distribute-lft1-inN/A

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

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, x, x\right)} \]
        16. lower-/.f6496.8

          \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{y}{z}}, x, x\right) \]
      5. Applied rewrites96.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y}{z}, x, x\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification91.0%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\left(y + z\right) \cdot x}{z} \leq -1 \cdot 10^{+166}:\\ \;\;\;\;\frac{x}{z} \cdot y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y}{z}, x, x\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 3: 73.2% accurate, 0.7× speedup?

    \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \begin{array}{l} \mathbf{if}\;z \leq -1.05 \cdot 10^{-42}:\\ \;\;\;\;\frac{x\_m}{1}\\ \mathbf{elif}\;z \leq 1.3 \cdot 10^{+22}:\\ \;\;\;\;\frac{x\_m}{z} \cdot y\\ \mathbf{else}:\\ \;\;\;\;\frac{x\_m}{1}\\ \end{array} \end{array} \]
    x\_m = (fabs.f64 x)
    x\_s = (copysign.f64 #s(literal 1 binary64) x)
    (FPCore (x_s x_m y z)
     :precision binary64
     (*
      x_s
      (if (<= z -1.05e-42)
        (/ x_m 1.0)
        (if (<= z 1.3e+22) (* (/ x_m z) y) (/ x_m 1.0)))))
    x\_m = fabs(x);
    x\_s = copysign(1.0, x);
    double code(double x_s, double x_m, double y, double z) {
    	double tmp;
    	if (z <= -1.05e-42) {
    		tmp = x_m / 1.0;
    	} else if (z <= 1.3e+22) {
    		tmp = (x_m / z) * y;
    	} else {
    		tmp = x_m / 1.0;
    	}
    	return x_s * tmp;
    }
    
    x\_m = abs(x)
    x\_s = copysign(1.0d0, x)
    real(8) function code(x_s, x_m, y, z)
        real(8), intent (in) :: x_s
        real(8), intent (in) :: x_m
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8) :: tmp
        if (z <= (-1.05d-42)) then
            tmp = x_m / 1.0d0
        else if (z <= 1.3d+22) then
            tmp = (x_m / z) * y
        else
            tmp = x_m / 1.0d0
        end if
        code = x_s * tmp
    end function
    
    x\_m = Math.abs(x);
    x\_s = Math.copySign(1.0, x);
    public static double code(double x_s, double x_m, double y, double z) {
    	double tmp;
    	if (z <= -1.05e-42) {
    		tmp = x_m / 1.0;
    	} else if (z <= 1.3e+22) {
    		tmp = (x_m / z) * y;
    	} else {
    		tmp = x_m / 1.0;
    	}
    	return x_s * tmp;
    }
    
    x\_m = math.fabs(x)
    x\_s = math.copysign(1.0, x)
    def code(x_s, x_m, y, z):
    	tmp = 0
    	if z <= -1.05e-42:
    		tmp = x_m / 1.0
    	elif z <= 1.3e+22:
    		tmp = (x_m / z) * y
    	else:
    		tmp = x_m / 1.0
    	return x_s * tmp
    
    x\_m = abs(x)
    x\_s = copysign(1.0, x)
    function code(x_s, x_m, y, z)
    	tmp = 0.0
    	if (z <= -1.05e-42)
    		tmp = Float64(x_m / 1.0);
    	elseif (z <= 1.3e+22)
    		tmp = Float64(Float64(x_m / z) * y);
    	else
    		tmp = Float64(x_m / 1.0);
    	end
    	return Float64(x_s * tmp)
    end
    
    x\_m = abs(x);
    x\_s = sign(x) * abs(1.0);
    function tmp_2 = code(x_s, x_m, y, z)
    	tmp = 0.0;
    	if (z <= -1.05e-42)
    		tmp = x_m / 1.0;
    	elseif (z <= 1.3e+22)
    		tmp = (x_m / z) * y;
    	else
    		tmp = x_m / 1.0;
    	end
    	tmp_2 = x_s * tmp;
    end
    
    x\_m = N[Abs[x], $MachinePrecision]
    x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * If[LessEqual[z, -1.05e-42], N[(x$95$m / 1.0), $MachinePrecision], If[LessEqual[z, 1.3e+22], N[(N[(x$95$m / z), $MachinePrecision] * y), $MachinePrecision], N[(x$95$m / 1.0), $MachinePrecision]]]), $MachinePrecision]
    
    \begin{array}{l}
    x\_m = \left|x\right|
    \\
    x\_s = \mathsf{copysign}\left(1, x\right)
    
    \\
    x\_s \cdot \begin{array}{l}
    \mathbf{if}\;z \leq -1.05 \cdot 10^{-42}:\\
    \;\;\;\;\frac{x\_m}{1}\\
    
    \mathbf{elif}\;z \leq 1.3 \cdot 10^{+22}:\\
    \;\;\;\;\frac{x\_m}{z} \cdot y\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{x\_m}{1}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if z < -1.05000000000000003e-42 or 1.3e22 < z

      1. Initial program 72.7%

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

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

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

          \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
        4. clear-numN/A

          \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
        5. un-div-invN/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        6. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        7. lower-/.f6499.9

          \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
        8. lift-+.f64N/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
        9. +-commutativeN/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
        10. lower-+.f6499.9

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
      4. Applied rewrites99.9%

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
      5. Taylor expanded in y around 0

        \[\leadsto \frac{x}{\color{blue}{1}} \]
      6. Step-by-step derivation
        1. Applied rewrites79.6%

          \[\leadsto \frac{x}{\color{blue}{1}} \]

        if -1.05000000000000003e-42 < z < 1.3e22

        1. Initial program 92.3%

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

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

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

            \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
          4. clear-numN/A

            \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
          5. un-div-invN/A

            \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
          6. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
          7. lower-/.f6492.3

            \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
          8. lift-+.f64N/A

            \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
          9. +-commutativeN/A

            \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
          10. lower-+.f6492.3

            \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
        4. Applied rewrites92.3%

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
        5. Taylor expanded in y around inf

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

            \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
          2. lower-*.f64N/A

            \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
          3. lower-/.f6473.7

            \[\leadsto \color{blue}{\frac{x}{z}} \cdot y \]
        7. Applied rewrites73.7%

          \[\leadsto \color{blue}{\frac{x}{z} \cdot y} \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 4: 96.0% accurate, 0.8× speedup?

      \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \frac{x\_m}{\frac{z}{y + z}} \end{array} \]
      x\_m = (fabs.f64 x)
      x\_s = (copysign.f64 #s(literal 1 binary64) x)
      (FPCore (x_s x_m y z) :precision binary64 (* x_s (/ x_m (/ z (+ y z)))))
      x\_m = fabs(x);
      x\_s = copysign(1.0, x);
      double code(double x_s, double x_m, double y, double z) {
      	return x_s * (x_m / (z / (y + z)));
      }
      
      x\_m = abs(x)
      x\_s = copysign(1.0d0, x)
      real(8) function code(x_s, x_m, y, z)
          real(8), intent (in) :: x_s
          real(8), intent (in) :: x_m
          real(8), intent (in) :: y
          real(8), intent (in) :: z
          code = x_s * (x_m / (z / (y + z)))
      end function
      
      x\_m = Math.abs(x);
      x\_s = Math.copySign(1.0, x);
      public static double code(double x_s, double x_m, double y, double z) {
      	return x_s * (x_m / (z / (y + z)));
      }
      
      x\_m = math.fabs(x)
      x\_s = math.copysign(1.0, x)
      def code(x_s, x_m, y, z):
      	return x_s * (x_m / (z / (y + z)))
      
      x\_m = abs(x)
      x\_s = copysign(1.0, x)
      function code(x_s, x_m, y, z)
      	return Float64(x_s * Float64(x_m / Float64(z / Float64(y + z))))
      end
      
      x\_m = abs(x);
      x\_s = sign(x) * abs(1.0);
      function tmp = code(x_s, x_m, y, z)
      	tmp = x_s * (x_m / (z / (y + z)));
      end
      
      x\_m = N[Abs[x], $MachinePrecision]
      x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * N[(x$95$m / N[(z / N[(y + z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      x\_m = \left|x\right|
      \\
      x\_s = \mathsf{copysign}\left(1, x\right)
      
      \\
      x\_s \cdot \frac{x\_m}{\frac{z}{y + z}}
      \end{array}
      
      Derivation
      1. Initial program 81.3%

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

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

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

          \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
        4. clear-numN/A

          \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
        5. un-div-invN/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        6. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        7. lower-/.f6496.6

          \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
        8. lift-+.f64N/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
        9. +-commutativeN/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
        10. lower-+.f6496.6

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
      4. Applied rewrites96.6%

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
      5. Final simplification96.6%

        \[\leadsto \frac{x}{\frac{z}{y + z}} \]
      6. Add Preprocessing

      Alternative 5: 51.3% accurate, 1.7× speedup?

      \[\begin{array}{l} x\_m = \left|x\right| \\ x\_s = \mathsf{copysign}\left(1, x\right) \\ x\_s \cdot \frac{x\_m}{1} \end{array} \]
      x\_m = (fabs.f64 x)
      x\_s = (copysign.f64 #s(literal 1 binary64) x)
      (FPCore (x_s x_m y z) :precision binary64 (* x_s (/ x_m 1.0)))
      x\_m = fabs(x);
      x\_s = copysign(1.0, x);
      double code(double x_s, double x_m, double y, double z) {
      	return x_s * (x_m / 1.0);
      }
      
      x\_m = abs(x)
      x\_s = copysign(1.0d0, x)
      real(8) function code(x_s, x_m, y, z)
          real(8), intent (in) :: x_s
          real(8), intent (in) :: x_m
          real(8), intent (in) :: y
          real(8), intent (in) :: z
          code = x_s * (x_m / 1.0d0)
      end function
      
      x\_m = Math.abs(x);
      x\_s = Math.copySign(1.0, x);
      public static double code(double x_s, double x_m, double y, double z) {
      	return x_s * (x_m / 1.0);
      }
      
      x\_m = math.fabs(x)
      x\_s = math.copysign(1.0, x)
      def code(x_s, x_m, y, z):
      	return x_s * (x_m / 1.0)
      
      x\_m = abs(x)
      x\_s = copysign(1.0, x)
      function code(x_s, x_m, y, z)
      	return Float64(x_s * Float64(x_m / 1.0))
      end
      
      x\_m = abs(x);
      x\_s = sign(x) * abs(1.0);
      function tmp = code(x_s, x_m, y, z)
      	tmp = x_s * (x_m / 1.0);
      end
      
      x\_m = N[Abs[x], $MachinePrecision]
      x\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[x$95$s_, x$95$m_, y_, z_] := N[(x$95$s * N[(x$95$m / 1.0), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      x\_m = \left|x\right|
      \\
      x\_s = \mathsf{copysign}\left(1, x\right)
      
      \\
      x\_s \cdot \frac{x\_m}{1}
      \end{array}
      
      Derivation
      1. Initial program 81.3%

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

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

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

          \[\leadsto \color{blue}{x \cdot \frac{y + z}{z}} \]
        4. clear-numN/A

          \[\leadsto x \cdot \color{blue}{\frac{1}{\frac{z}{y + z}}} \]
        5. un-div-invN/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        6. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{x}{\frac{z}{y + z}}} \]
        7. lower-/.f6496.6

          \[\leadsto \frac{x}{\color{blue}{\frac{z}{y + z}}} \]
        8. lift-+.f64N/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{y + z}}} \]
        9. +-commutativeN/A

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
        10. lower-+.f6496.6

          \[\leadsto \frac{x}{\frac{z}{\color{blue}{z + y}}} \]
      4. Applied rewrites96.6%

        \[\leadsto \color{blue}{\frac{x}{\frac{z}{z + y}}} \]
      5. Taylor expanded in y around 0

        \[\leadsto \frac{x}{\color{blue}{1}} \]
      6. Step-by-step derivation
        1. Applied rewrites55.6%

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

        Developer Target 1: 96.0% accurate, 0.8× speedup?

        \[\begin{array}{l} \\ \frac{x}{\frac{z}{y + z}} \end{array} \]
        (FPCore (x y z) :precision binary64 (/ x (/ z (+ y z))))
        double code(double x, double y, double z) {
        	return x / (z / (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 = x / (z / (y + z))
        end function
        
        public static double code(double x, double y, double z) {
        	return x / (z / (y + z));
        }
        
        def code(x, y, z):
        	return x / (z / (y + z))
        
        function code(x, y, z)
        	return Float64(x / Float64(z / Float64(y + z)))
        end
        
        function tmp = code(x, y, z)
        	tmp = x / (z / (y + z));
        end
        
        code[x_, y_, z_] := N[(x / N[(z / N[(y + z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{x}{\frac{z}{y + z}}
        \end{array}
        

        Reproduce

        ?
        herbie shell --seed 2024294 
        (FPCore (x y z)
          :name "Numeric.SpecFunctions:choose from math-functions-0.1.5.2"
          :precision binary64
        
          :alt
          (! :herbie-platform default (/ x (/ z (+ y z))))
        
          (/ (* x (+ y z)) z))