fabs fraction 1

Percentage Accurate: 91.8% → 99.9%
Time: 6.8s
Alternatives: 8
Speedup: 1.6×

Specification

?
\[\begin{array}{l} \\ \left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \end{array} \]
(FPCore (x y z) :precision binary64 (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))
double code(double x, double y, double z) {
	return fabs((((x + 4.0) / y) - ((x / 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 = abs((((x + 4.0d0) / y) - ((x / y) * z)))
end function
public static double code(double x, double y, double z) {
	return Math.abs((((x + 4.0) / y) - ((x / y) * z)));
}
def code(x, y, z):
	return math.fabs((((x + 4.0) / y) - ((x / y) * z)))
function code(x, y, z)
	return abs(Float64(Float64(Float64(x + 4.0) / y) - Float64(Float64(x / y) * z)))
end
function tmp = code(x, y, z)
	tmp = abs((((x + 4.0) / y) - ((x / y) * z)));
end
code[x_, y_, z_] := N[Abs[N[(N[(N[(x + 4.0), $MachinePrecision] / y), $MachinePrecision] - N[(N[(x / y), $MachinePrecision] * z), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|
\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: 91.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right| \end{array} \]
(FPCore (x y z) :precision binary64 (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))
double code(double x, double y, double z) {
	return fabs((((x + 4.0) / y) - ((x / 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 = abs((((x + 4.0d0) / y) - ((x / y) * z)))
end function
public static double code(double x, double y, double z) {
	return Math.abs((((x + 4.0) / y) - ((x / y) * z)));
}
def code(x, y, z):
	return math.fabs((((x + 4.0) / y) - ((x / y) * z)))
function code(x, y, z)
	return abs(Float64(Float64(Float64(x + 4.0) / y) - Float64(Float64(x / y) * z)))
end
function tmp = code(x, y, z)
	tmp = abs((((x + 4.0) / y) - ((x / y) * z)));
end
code[x_, y_, z_] := N[Abs[N[(N[(N[(x + 4.0), $MachinePrecision] / y), $MachinePrecision] - N[(N[(x / y), $MachinePrecision] * z), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x + 4}{y} - \frac{x}{y} \cdot z\right|
\end{array}

Alternative 1: 99.9% accurate, 0.9× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;y\_m \leq 2 \cdot 10^{-27}:\\ \;\;\;\;\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\mathsf{fma}\left(-x, \frac{z}{y\_m}, \frac{4 + x}{y\_m}\right)\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (<= y_m 2e-27)
   (fabs (/ (fma z x (- -4.0 x)) y_m))
   (fabs (fma (- x) (/ z y_m) (/ (+ 4.0 x) y_m)))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if (y_m <= 2e-27) {
		tmp = fabs((fma(z, x, (-4.0 - x)) / y_m));
	} else {
		tmp = fabs(fma(-x, (z / y_m), ((4.0 + x) / y_m)));
	}
	return tmp;
}
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if (y_m <= 2e-27)
		tmp = abs(Float64(fma(z, x, Float64(-4.0 - x)) / y_m));
	else
		tmp = abs(fma(Float64(-x), Float64(z / y_m), Float64(Float64(4.0 + x) / y_m)));
	end
	return tmp
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[LessEqual[y$95$m, 2e-27], N[Abs[N[(N[(z * x + N[(-4.0 - x), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[((-x) * N[(z / y$95$m), $MachinePrecision] + N[(N[(4.0 + x), $MachinePrecision] / y$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;y\_m \leq 2 \cdot 10^{-27}:\\
\;\;\;\;\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\mathsf{fma}\left(-x, \frac{z}{y\_m}, \frac{4 + x}{y\_m}\right)\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < 2.0000000000000001e-27

    1. Initial program 88.2%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval98.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites98.9%

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

    if 2.0000000000000001e-27 < y

    1. Initial program 97.0%

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      2. sub-negN/A

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

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

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

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

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

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

        \[\leadsto \left|\color{blue}{\left(\mathsf{neg}\left(x\right)\right) \cdot \frac{z}{y}} + \frac{x + 4}{y}\right| \]
      9. lower-fma.f64N/A

        \[\leadsto \left|\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(x\right), \frac{z}{y}, \frac{x + 4}{y}\right)}\right| \]
      10. lower-neg.f64N/A

        \[\leadsto \left|\mathsf{fma}\left(\color{blue}{-x}, \frac{z}{y}, \frac{x + 4}{y}\right)\right| \]
      11. lower-/.f6499.8

        \[\leadsto \left|\mathsf{fma}\left(-x, \color{blue}{\frac{z}{y}}, \frac{x + 4}{y}\right)\right| \]
      12. lift-+.f64N/A

        \[\leadsto \left|\mathsf{fma}\left(-x, \frac{z}{y}, \frac{\color{blue}{x + 4}}{y}\right)\right| \]
      13. +-commutativeN/A

        \[\leadsto \left|\mathsf{fma}\left(-x, \frac{z}{y}, \frac{\color{blue}{4 + x}}{y}\right)\right| \]
      14. lower-+.f6499.8

        \[\leadsto \left|\mathsf{fma}\left(-x, \frac{z}{y}, \frac{\color{blue}{4 + x}}{y}\right)\right| \]
    4. Applied rewrites99.8%

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

Alternative 2: 84.8% accurate, 1.2× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;z \leq -5.8 \cdot 10^{+54} \lor \neg \left(z \leq 7.6 \cdot 10^{+113}\right):\\ \;\;\;\;\left|\frac{z}{y\_m} \cdot x\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (or (<= z -5.8e+54) (not (<= z 7.6e+113)))
   (fabs (* (/ z y_m) x))
   (fabs (/ (- -4.0 x) y_m))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if ((z <= -5.8e+54) || !(z <= 7.6e+113)) {
		tmp = fabs(((z / y_m) * x));
	} else {
		tmp = fabs(((-4.0 - x) / y_m));
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8) :: tmp
    if ((z <= (-5.8d+54)) .or. (.not. (z <= 7.6d+113))) then
        tmp = abs(((z / y_m) * x))
    else
        tmp = abs((((-4.0d0) - x) / y_m))
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z) {
	double tmp;
	if ((z <= -5.8e+54) || !(z <= 7.6e+113)) {
		tmp = Math.abs(((z / y_m) * x));
	} else {
		tmp = Math.abs(((-4.0 - x) / y_m));
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z):
	tmp = 0
	if (z <= -5.8e+54) or not (z <= 7.6e+113):
		tmp = math.fabs(((z / y_m) * x))
	else:
		tmp = math.fabs(((-4.0 - x) / y_m))
	return tmp
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if ((z <= -5.8e+54) || !(z <= 7.6e+113))
		tmp = abs(Float64(Float64(z / y_m) * x));
	else
		tmp = abs(Float64(Float64(-4.0 - x) / y_m));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z)
	tmp = 0.0;
	if ((z <= -5.8e+54) || ~((z <= 7.6e+113)))
		tmp = abs(((z / y_m) * x));
	else
		tmp = abs(((-4.0 - x) / y_m));
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[Or[LessEqual[z, -5.8e+54], N[Not[LessEqual[z, 7.6e+113]], $MachinePrecision]], N[Abs[N[(N[(z / y$95$m), $MachinePrecision] * x), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[(-4.0 - x), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;z \leq -5.8 \cdot 10^{+54} \lor \neg \left(z \leq 7.6 \cdot 10^{+113}\right):\\
\;\;\;\;\left|\frac{z}{y\_m} \cdot x\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -5.7999999999999997e54 or 7.6000000000000007e113 < z

    1. Initial program 84.0%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval94.3

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites94.3%

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

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

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

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

        \[\leadsto \left|\color{blue}{\frac{z}{y} \cdot x}\right| \]
      4. lower-/.f6489.4

        \[\leadsto \left|\color{blue}{\frac{z}{y}} \cdot x\right| \]
    7. Applied rewrites89.4%

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

    if -5.7999999999999997e54 < z < 7.6000000000000007e113

    1. Initial program 94.0%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval99.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites99.9%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in z around 0

      \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
    6. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
      3. mul-1-negN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
      5. lower--.f6492.8

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    7. Applied rewrites92.8%

      \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -5.8 \cdot 10^{+54} \lor \neg \left(z \leq 7.6 \cdot 10^{+113}\right):\\ \;\;\;\;\left|\frac{z}{y} \cdot x\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{-4 - x}{y}\right|\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 83.9% accurate, 1.2× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;z \leq -5.8 \cdot 10^{+54}:\\ \;\;\;\;\left|\left(-z\right) \cdot \frac{x}{y\_m}\right|\\ \mathbf{elif}\;z \leq 1.45 \cdot 10^{+114}:\\ \;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{x \cdot z}{y\_m}\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (<= z -5.8e+54)
   (fabs (* (- z) (/ x y_m)))
   (if (<= z 1.45e+114) (fabs (/ (- -4.0 x) y_m)) (fabs (/ (* x z) y_m)))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if (z <= -5.8e+54) {
		tmp = fabs((-z * (x / y_m)));
	} else if (z <= 1.45e+114) {
		tmp = fabs(((-4.0 - x) / y_m));
	} else {
		tmp = fabs(((x * z) / y_m));
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8) :: tmp
    if (z <= (-5.8d+54)) then
        tmp = abs((-z * (x / y_m)))
    else if (z <= 1.45d+114) then
        tmp = abs((((-4.0d0) - x) / y_m))
    else
        tmp = abs(((x * z) / y_m))
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z) {
	double tmp;
	if (z <= -5.8e+54) {
		tmp = Math.abs((-z * (x / y_m)));
	} else if (z <= 1.45e+114) {
		tmp = Math.abs(((-4.0 - x) / y_m));
	} else {
		tmp = Math.abs(((x * z) / y_m));
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z):
	tmp = 0
	if z <= -5.8e+54:
		tmp = math.fabs((-z * (x / y_m)))
	elif z <= 1.45e+114:
		tmp = math.fabs(((-4.0 - x) / y_m))
	else:
		tmp = math.fabs(((x * z) / y_m))
	return tmp
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if (z <= -5.8e+54)
		tmp = abs(Float64(Float64(-z) * Float64(x / y_m)));
	elseif (z <= 1.45e+114)
		tmp = abs(Float64(Float64(-4.0 - x) / y_m));
	else
		tmp = abs(Float64(Float64(x * z) / y_m));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z)
	tmp = 0.0;
	if (z <= -5.8e+54)
		tmp = abs((-z * (x / y_m)));
	elseif (z <= 1.45e+114)
		tmp = abs(((-4.0 - x) / y_m));
	else
		tmp = abs(((x * z) / y_m));
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[LessEqual[z, -5.8e+54], N[Abs[N[((-z) * N[(x / y$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[LessEqual[z, 1.45e+114], N[Abs[N[(N[(-4.0 - x), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[(x * z), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;z \leq -5.8 \cdot 10^{+54}:\\
\;\;\;\;\left|\left(-z\right) \cdot \frac{x}{y\_m}\right|\\

\mathbf{elif}\;z \leq 1.45 \cdot 10^{+114}:\\
\;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\frac{x \cdot z}{y\_m}\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if z < -5.7999999999999997e54

    1. Initial program 98.1%

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

      \[\leadsto \left|\color{blue}{-1 \cdot \frac{x \cdot z}{y}}\right| \]
    4. Step-by-step derivation
      1. *-commutativeN/A

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

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

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

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

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

        \[\leadsto \left|\color{blue}{\left(-z\right)} \cdot \frac{x}{y}\right| \]
      7. lower-/.f6490.0

        \[\leadsto \left|\left(-z\right) \cdot \color{blue}{\frac{x}{y}}\right| \]
    5. Applied rewrites90.0%

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

    if -5.7999999999999997e54 < z < 1.45e114

    1. Initial program 94.0%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval99.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites99.9%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in z around 0

      \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
    6. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
      3. mul-1-negN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
      5. lower--.f6492.8

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    7. Applied rewrites92.8%

      \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]

    if 1.45e114 < z

    1. Initial program 70.2%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval97.5

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

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

      \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
    6. Step-by-step derivation
      1. lower-*.f6493.4

        \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
    7. Applied rewrites93.4%

      \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 4: 83.9% accurate, 1.2× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;z \leq -5.8 \cdot 10^{+54}:\\ \;\;\;\;\left|\frac{z}{y\_m} \cdot x\right|\\ \mathbf{elif}\;z \leq 1.45 \cdot 10^{+114}:\\ \;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{x \cdot z}{y\_m}\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (<= z -5.8e+54)
   (fabs (* (/ z y_m) x))
   (if (<= z 1.45e+114) (fabs (/ (- -4.0 x) y_m)) (fabs (/ (* x z) y_m)))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if (z <= -5.8e+54) {
		tmp = fabs(((z / y_m) * x));
	} else if (z <= 1.45e+114) {
		tmp = fabs(((-4.0 - x) / y_m));
	} else {
		tmp = fabs(((x * z) / y_m));
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8) :: tmp
    if (z <= (-5.8d+54)) then
        tmp = abs(((z / y_m) * x))
    else if (z <= 1.45d+114) then
        tmp = abs((((-4.0d0) - x) / y_m))
    else
        tmp = abs(((x * z) / y_m))
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z) {
	double tmp;
	if (z <= -5.8e+54) {
		tmp = Math.abs(((z / y_m) * x));
	} else if (z <= 1.45e+114) {
		tmp = Math.abs(((-4.0 - x) / y_m));
	} else {
		tmp = Math.abs(((x * z) / y_m));
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z):
	tmp = 0
	if z <= -5.8e+54:
		tmp = math.fabs(((z / y_m) * x))
	elif z <= 1.45e+114:
		tmp = math.fabs(((-4.0 - x) / y_m))
	else:
		tmp = math.fabs(((x * z) / y_m))
	return tmp
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if (z <= -5.8e+54)
		tmp = abs(Float64(Float64(z / y_m) * x));
	elseif (z <= 1.45e+114)
		tmp = abs(Float64(Float64(-4.0 - x) / y_m));
	else
		tmp = abs(Float64(Float64(x * z) / y_m));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z)
	tmp = 0.0;
	if (z <= -5.8e+54)
		tmp = abs(((z / y_m) * x));
	elseif (z <= 1.45e+114)
		tmp = abs(((-4.0 - x) / y_m));
	else
		tmp = abs(((x * z) / y_m));
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[LessEqual[z, -5.8e+54], N[Abs[N[(N[(z / y$95$m), $MachinePrecision] * x), $MachinePrecision]], $MachinePrecision], If[LessEqual[z, 1.45e+114], N[Abs[N[(N[(-4.0 - x), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[(x * z), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;z \leq -5.8 \cdot 10^{+54}:\\
\;\;\;\;\left|\frac{z}{y\_m} \cdot x\right|\\

\mathbf{elif}\;z \leq 1.45 \cdot 10^{+114}:\\
\;\;\;\;\left|\frac{-4 - x}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\frac{x \cdot z}{y\_m}\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if z < -5.7999999999999997e54

    1. Initial program 98.1%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval90.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites90.9%

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

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

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

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

        \[\leadsto \left|\color{blue}{\frac{z}{y} \cdot x}\right| \]
      4. lower-/.f6487.4

        \[\leadsto \left|\color{blue}{\frac{z}{y}} \cdot x\right| \]
    7. Applied rewrites87.4%

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

    if -5.7999999999999997e54 < z < 1.45e114

    1. Initial program 94.0%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval99.9

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites99.9%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in z around 0

      \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
    6. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
      3. mul-1-negN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
      5. lower--.f6492.8

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    7. Applied rewrites92.8%

      \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]

    if 1.45e114 < z

    1. Initial program 70.2%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval97.5

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

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

      \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
    6. Step-by-step derivation
      1. lower-*.f6493.4

        \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
    7. Applied rewrites93.4%

      \[\leadsto \left|\frac{\color{blue}{x \cdot z}}{y}\right| \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 5: 68.4% accurate, 1.3× speedup?

\[\begin{array}{l} y_m = \left|y\right| \\ \begin{array}{l} \mathbf{if}\;x \leq -10.5 \lor \neg \left(x \leq 4\right):\\ \;\;\;\;\left|\frac{-x}{y\_m}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{4}{y\_m}\right|\\ \end{array} \end{array} \]
y_m = (fabs.f64 y)
(FPCore (x y_m z)
 :precision binary64
 (if (or (<= x -10.5) (not (<= x 4.0)))
   (fabs (/ (- x) y_m))
   (fabs (/ 4.0 y_m))))
y_m = fabs(y);
double code(double x, double y_m, double z) {
	double tmp;
	if ((x <= -10.5) || !(x <= 4.0)) {
		tmp = fabs((-x / y_m));
	} else {
		tmp = fabs((4.0 / y_m));
	}
	return tmp;
}
y_m = abs(y)
real(8) function code(x, y_m, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y_m
    real(8), intent (in) :: z
    real(8) :: tmp
    if ((x <= (-10.5d0)) .or. (.not. (x <= 4.0d0))) then
        tmp = abs((-x / y_m))
    else
        tmp = abs((4.0d0 / y_m))
    end if
    code = tmp
end function
y_m = Math.abs(y);
public static double code(double x, double y_m, double z) {
	double tmp;
	if ((x <= -10.5) || !(x <= 4.0)) {
		tmp = Math.abs((-x / y_m));
	} else {
		tmp = Math.abs((4.0 / y_m));
	}
	return tmp;
}
y_m = math.fabs(y)
def code(x, y_m, z):
	tmp = 0
	if (x <= -10.5) or not (x <= 4.0):
		tmp = math.fabs((-x / y_m))
	else:
		tmp = math.fabs((4.0 / y_m))
	return tmp
y_m = abs(y)
function code(x, y_m, z)
	tmp = 0.0
	if ((x <= -10.5) || !(x <= 4.0))
		tmp = abs(Float64(Float64(-x) / y_m));
	else
		tmp = abs(Float64(4.0 / y_m));
	end
	return tmp
end
y_m = abs(y);
function tmp_2 = code(x, y_m, z)
	tmp = 0.0;
	if ((x <= -10.5) || ~((x <= 4.0)))
		tmp = abs((-x / y_m));
	else
		tmp = abs((4.0 / y_m));
	end
	tmp_2 = tmp;
end
y_m = N[Abs[y], $MachinePrecision]
code[x_, y$95$m_, z_] := If[Or[LessEqual[x, -10.5], N[Not[LessEqual[x, 4.0]], $MachinePrecision]], N[Abs[N[((-x) / y$95$m), $MachinePrecision]], $MachinePrecision], N[Abs[N[(4.0 / y$95$m), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
y_m = \left|y\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq -10.5 \lor \neg \left(x \leq 4\right):\\
\;\;\;\;\left|\frac{-x}{y\_m}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|\frac{4}{y\_m}\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -10.5 or 4 < x

    1. Initial program 83.6%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval96.2

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites96.2%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in z around 0

      \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
    6. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
      3. mul-1-negN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
      5. lower--.f6468.6

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    7. Applied rewrites68.6%

      \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    8. Taylor expanded in x around inf

      \[\leadsto \left|\frac{-1 \cdot \color{blue}{x}}{y}\right| \]
    9. Step-by-step derivation
      1. Applied rewrites67.9%

        \[\leadsto \left|\frac{-x}{y}\right| \]

      if -10.5 < x < 4

      1. Initial program 97.8%

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

        \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
      4. Step-by-step derivation
        1. lower-/.f6470.8

          \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
      5. Applied rewrites70.8%

        \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
    10. Recombined 2 regimes into one program.
    11. Final simplification69.3%

      \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -10.5 \lor \neg \left(x \leq 4\right):\\ \;\;\;\;\left|\frac{-x}{y}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|\frac{4}{y}\right|\\ \end{array} \]
    12. Add Preprocessing

    Alternative 6: 95.7% accurate, 1.6× speedup?

    \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y\_m}\right| \end{array} \]
    y_m = (fabs.f64 y)
    (FPCore (x y_m z) :precision binary64 (fabs (/ (fma z x (- -4.0 x)) y_m)))
    y_m = fabs(y);
    double code(double x, double y_m, double z) {
    	return fabs((fma(z, x, (-4.0 - x)) / y_m));
    }
    
    y_m = abs(y)
    function code(x, y_m, z)
    	return abs(Float64(fma(z, x, Float64(-4.0 - x)) / y_m))
    end
    
    y_m = N[Abs[y], $MachinePrecision]
    code[x_, y$95$m_, z_] := N[Abs[N[(N[(z * x + N[(-4.0 - x), $MachinePrecision]), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]
    
    \begin{array}{l}
    y_m = \left|y\right|
    
    \\
    \left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y\_m}\right|
    \end{array}
    
    Derivation
    1. Initial program 90.6%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval98.0

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites98.0%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Add Preprocessing

    Alternative 7: 69.4% accurate, 2.1× speedup?

    \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{-4 - x}{y\_m}\right| \end{array} \]
    y_m = (fabs.f64 y)
    (FPCore (x y_m z) :precision binary64 (fabs (/ (- -4.0 x) y_m)))
    y_m = fabs(y);
    double code(double x, double y_m, double z) {
    	return fabs(((-4.0 - x) / y_m));
    }
    
    y_m = abs(y)
    real(8) function code(x, y_m, z)
        real(8), intent (in) :: x
        real(8), intent (in) :: y_m
        real(8), intent (in) :: z
        code = abs((((-4.0d0) - x) / y_m))
    end function
    
    y_m = Math.abs(y);
    public static double code(double x, double y_m, double z) {
    	return Math.abs(((-4.0 - x) / y_m));
    }
    
    y_m = math.fabs(y)
    def code(x, y_m, z):
    	return math.fabs(((-4.0 - x) / y_m))
    
    y_m = abs(y)
    function code(x, y_m, z)
    	return abs(Float64(Float64(-4.0 - x) / y_m))
    end
    
    y_m = abs(y);
    function tmp = code(x, y_m, z)
    	tmp = abs(((-4.0 - x) / y_m));
    end
    
    y_m = N[Abs[y], $MachinePrecision]
    code[x_, y$95$m_, z_] := N[Abs[N[(N[(-4.0 - x), $MachinePrecision] / y$95$m), $MachinePrecision]], $MachinePrecision]
    
    \begin{array}{l}
    y_m = \left|y\right|
    
    \\
    \left|\frac{-4 - x}{y\_m}\right|
    \end{array}
    
    Derivation
    1. Initial program 90.6%

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

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

        \[\leadsto \left|\color{blue}{\frac{x + 4}{y} - \frac{x}{y} \cdot z}\right| \]
      3. fabs-subN/A

        \[\leadsto \color{blue}{\left|\frac{x}{y} \cdot z - \frac{x + 4}{y}\right|} \]
      4. lower-fabs.f64N/A

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

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

        \[\leadsto \left|\color{blue}{\frac{x}{y}} \cdot z - \frac{x + 4}{y}\right| \]
      7. associate-*l/N/A

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

        \[\leadsto \left|\frac{x \cdot z}{y} - \color{blue}{\frac{x + 4}{y}}\right| \]
      9. sub-divN/A

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

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

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

        \[\leadsto \left|\frac{\color{blue}{z \cdot x} + \left(\mathsf{neg}\left(\left(x + 4\right)\right)\right)}{y}\right| \]
      13. lower-fma.f64N/A

        \[\leadsto \left|\frac{\color{blue}{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\left(x + 4\right)\right)\right)}}{y}\right| \]
      14. lift-+.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(x + 4\right)}\right)\right)}{y}\right| \]
      15. +-commutativeN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \mathsf{neg}\left(\color{blue}{\left(4 + x\right)}\right)\right)}{y}\right| \]
      16. distribute-neg-inN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) + \left(\mathsf{neg}\left(x\right)\right)}\right)}{y}\right| \]
      17. unsub-negN/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      18. lower--.f64N/A

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{\left(\mathsf{neg}\left(4\right)\right) - x}\right)}{y}\right| \]
      19. metadata-eval98.0

        \[\leadsto \left|\frac{\mathsf{fma}\left(z, x, \color{blue}{-4} - x\right)}{y}\right| \]
    4. Applied rewrites98.0%

      \[\leadsto \color{blue}{\left|\frac{\mathsf{fma}\left(z, x, -4 - x\right)}{y}\right|} \]
    5. Taylor expanded in z around 0

      \[\leadsto \left|\frac{\color{blue}{-1 \cdot \left(4 + x\right)}}{y}\right| \]
    6. Step-by-step derivation
      1. distribute-lft-inN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4} + -1 \cdot x}{y}\right| \]
      3. mul-1-negN/A

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

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
      5. lower--.f6470.3

        \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    7. Applied rewrites70.3%

      \[\leadsto \left|\frac{\color{blue}{-4 - x}}{y}\right| \]
    8. Add Preprocessing

    Alternative 8: 39.4% accurate, 2.6× speedup?

    \[\begin{array}{l} y_m = \left|y\right| \\ \left|\frac{4}{y\_m}\right| \end{array} \]
    y_m = (fabs.f64 y)
    (FPCore (x y_m z) :precision binary64 (fabs (/ 4.0 y_m)))
    y_m = fabs(y);
    double code(double x, double y_m, double z) {
    	return fabs((4.0 / y_m));
    }
    
    y_m = abs(y)
    real(8) function code(x, y_m, z)
        real(8), intent (in) :: x
        real(8), intent (in) :: y_m
        real(8), intent (in) :: z
        code = abs((4.0d0 / y_m))
    end function
    
    y_m = Math.abs(y);
    public static double code(double x, double y_m, double z) {
    	return Math.abs((4.0 / y_m));
    }
    
    y_m = math.fabs(y)
    def code(x, y_m, z):
    	return math.fabs((4.0 / y_m))
    
    y_m = abs(y)
    function code(x, y_m, z)
    	return abs(Float64(4.0 / y_m))
    end
    
    y_m = abs(y);
    function tmp = code(x, y_m, z)
    	tmp = abs((4.0 / y_m));
    end
    
    y_m = N[Abs[y], $MachinePrecision]
    code[x_, y$95$m_, z_] := N[Abs[N[(4.0 / y$95$m), $MachinePrecision]], $MachinePrecision]
    
    \begin{array}{l}
    y_m = \left|y\right|
    
    \\
    \left|\frac{4}{y\_m}\right|
    \end{array}
    
    Derivation
    1. Initial program 90.6%

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

      \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
    4. Step-by-step derivation
      1. lower-/.f6437.8

        \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
    5. Applied rewrites37.8%

      \[\leadsto \left|\color{blue}{\frac{4}{y}}\right| \]
    6. Add Preprocessing

    Reproduce

    ?
    herbie shell --seed 2024318 
    (FPCore (x y z)
      :name "fabs fraction 1"
      :precision binary64
      (fabs (- (/ (+ x 4.0) y) (* (/ x y) z))))