Data.Approximate.Numerics:blog from approximate-0.2.2.1

Percentage Accurate: 99.6% → 99.9%
Time: 8.5s
Alternatives: 10
Speedup: 1.1×

Specification

?
\[\begin{array}{l} \\ \frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))
double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (6.0d0 * (x - 1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))
end function
public static double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * Math.sqrt(x)));
}
def code(x):
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * math.sqrt(x)))
function code(x)
	return Float64(Float64(6.0 * Float64(x - 1.0)) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x))))
end
function tmp = code(x)
	tmp = (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
end
code[x_] := N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}
\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 10 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))
double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (6.0d0 * (x - 1.0d0)) / ((x + 1.0d0) + (4.0d0 * sqrt(x)))
end function
public static double code(double x) {
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * Math.sqrt(x)));
}
def code(x):
	return (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * math.sqrt(x)))
function code(x)
	return Float64(Float64(6.0 * Float64(x - 1.0)) / Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x))))
end
function tmp = code(x)
	tmp = (6.0 * (x - 1.0)) / ((x + 1.0) + (4.0 * sqrt(x)));
end
code[x_] := N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}
\end{array}

Alternative 1: 99.9% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{x - 1}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1} \cdot 6 \end{array} \]
(FPCore (x)
 :precision binary64
 (* (/ (- x 1.0) (+ (fma 4.0 (sqrt x) x) 1.0)) 6.0))
double code(double x) {
	return ((x - 1.0) / (fma(4.0, sqrt(x), x) + 1.0)) * 6.0;
}
function code(x)
	return Float64(Float64(Float64(x - 1.0) / Float64(fma(4.0, sqrt(x), x) + 1.0)) * 6.0)
end
code[x_] := N[(N[(N[(x - 1.0), $MachinePrecision] / N[(N[(4.0 * N[Sqrt[x], $MachinePrecision] + x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision] * 6.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{x - 1}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1} \cdot 6
\end{array}
Derivation
  1. Initial program 99.8%

    \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
    2. lift-*.f64N/A

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

      \[\leadsto \color{blue}{6 \cdot \frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
    4. *-commutativeN/A

      \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
    5. lower-*.f64N/A

      \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
    6. lower-/.f6499.9

      \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
    7. lift-+.f64N/A

      \[\leadsto \frac{x - 1}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
    8. +-commutativeN/A

      \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + \left(x + 1\right)}} \cdot 6 \]
    9. lift-*.f64N/A

      \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x}} + \left(x + 1\right)} \cdot 6 \]
    10. *-commutativeN/A

      \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + \left(x + 1\right)} \cdot 6 \]
    11. lower-fma.f6499.9

      \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x + 1\right)}} \cdot 6 \]
    12. lift-+.f64N/A

      \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{x + 1}\right)} \cdot 6 \]
    13. +-commutativeN/A

      \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
    14. lower-+.f6499.9

      \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
  4. Applied rewrites99.9%

    \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)} \cdot 6} \]
  5. Step-by-step derivation
    1. lift-fma.f64N/A

      \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4 + \left(1 + x\right)}} \cdot 6 \]
    2. lift-+.f64N/A

      \[\leadsto \frac{x - 1}{\sqrt{x} \cdot 4 + \color{blue}{\left(1 + x\right)}} \cdot 6 \]
    3. +-commutativeN/A

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

      \[\leadsto \frac{x - 1}{\color{blue}{\left(\sqrt{x} \cdot 4 + x\right) + 1}} \cdot 6 \]
    5. lower-+.f64N/A

      \[\leadsto \frac{x - 1}{\color{blue}{\left(\sqrt{x} \cdot 4 + x\right) + 1}} \cdot 6 \]
    6. *-commutativeN/A

      \[\leadsto \frac{x - 1}{\left(\color{blue}{4 \cdot \sqrt{x}} + x\right) + 1} \cdot 6 \]
    7. lower-fma.f6499.9

      \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right)} + 1} \cdot 6 \]
  6. Applied rewrites99.9%

    \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \cdot 6 \]
  7. Add Preprocessing

Alternative 2: 51.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(x + 1\right) + 4 \cdot \sqrt{x}\\ \mathbf{if}\;\frac{6 \cdot \left(x - 1\right)}{t\_0} \leq -5:\\ \;\;\;\;\frac{-6}{t\_0}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (+ x 1.0) (* 4.0 (sqrt x)))))
   (if (<= (/ (* 6.0 (- x 1.0)) t_0) -5.0)
     (/ -6.0 t_0)
     (* 1.5 (sqrt (pow x -1.0))))))
double code(double x) {
	double t_0 = (x + 1.0) + (4.0 * sqrt(x));
	double tmp;
	if (((6.0 * (x - 1.0)) / t_0) <= -5.0) {
		tmp = -6.0 / t_0;
	} else {
		tmp = 1.5 * sqrt(pow(x, -1.0));
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (x + 1.0d0) + (4.0d0 * sqrt(x))
    if (((6.0d0 * (x - 1.0d0)) / t_0) <= (-5.0d0)) then
        tmp = (-6.0d0) / t_0
    else
        tmp = 1.5d0 * sqrt((x ** (-1.0d0)))
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (x + 1.0) + (4.0 * Math.sqrt(x));
	double tmp;
	if (((6.0 * (x - 1.0)) / t_0) <= -5.0) {
		tmp = -6.0 / t_0;
	} else {
		tmp = 1.5 * Math.sqrt(Math.pow(x, -1.0));
	}
	return tmp;
}
def code(x):
	t_0 = (x + 1.0) + (4.0 * math.sqrt(x))
	tmp = 0
	if ((6.0 * (x - 1.0)) / t_0) <= -5.0:
		tmp = -6.0 / t_0
	else:
		tmp = 1.5 * math.sqrt(math.pow(x, -1.0))
	return tmp
function code(x)
	t_0 = Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x)))
	tmp = 0.0
	if (Float64(Float64(6.0 * Float64(x - 1.0)) / t_0) <= -5.0)
		tmp = Float64(-6.0 / t_0);
	else
		tmp = Float64(1.5 * sqrt((x ^ -1.0)));
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (x + 1.0) + (4.0 * sqrt(x));
	tmp = 0.0;
	if (((6.0 * (x - 1.0)) / t_0) <= -5.0)
		tmp = -6.0 / t_0;
	else
		tmp = 1.5 * sqrt((x ^ -1.0));
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision], -5.0], N[(-6.0 / t$95$0), $MachinePrecision], N[(1.5 * N[Sqrt[N[Power[x, -1.0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(x + 1\right) + 4 \cdot \sqrt{x}\\
\mathbf{if}\;\frac{6 \cdot \left(x - 1\right)}{t\_0} \leq -5:\\
\;\;\;\;\frac{-6}{t\_0}\\

\mathbf{else}:\\
\;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (*.f64 #s(literal 6 binary64) (-.f64 x #s(literal 1 binary64))) (+.f64 (+.f64 x #s(literal 1 binary64)) (*.f64 #s(literal 4 binary64) (sqrt.f64 x)))) < -5

    1. Initial program 99.8%

      \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{\color{blue}{-6}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
    4. Step-by-step derivation
      1. Applied rewrites97.7%

        \[\leadsto \frac{\color{blue}{-6}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]

      if -5 < (/.f64 (*.f64 #s(literal 6 binary64) (-.f64 x #s(literal 1 binary64))) (+.f64 (+.f64 x #s(literal 1 binary64)) (*.f64 #s(literal 4 binary64) (sqrt.f64 x))))

      1. Initial program 99.7%

        \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
      4. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
        2. +-commutativeN/A

          \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
        3. *-commutativeN/A

          \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
        4. lower-fma.f64N/A

          \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
        5. lower-sqrt.f641.9

          \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
      5. Applied rewrites1.9%

        \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
      6. Taylor expanded in x around -inf

        \[\leadsto \frac{3}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
      7. Step-by-step derivation
        1. Applied rewrites7.0%

          \[\leadsto 1.5 \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
      8. Recombined 2 regimes into one program.
      9. Final simplification54.1%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \leq -5:\\ \;\;\;\;\frac{-6}{\left(x + 1\right) + 4 \cdot \sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \]
      10. Add Preprocessing

      Alternative 3: 51.5% accurate, 0.3× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (if (<= x 1.0) (/ -6.0 (fma (sqrt x) 4.0 1.0)) (* 1.5 (sqrt (pow x -1.0)))))
      double code(double x) {
      	double tmp;
      	if (x <= 1.0) {
      		tmp = -6.0 / fma(sqrt(x), 4.0, 1.0);
      	} else {
      		tmp = 1.5 * sqrt(pow(x, -1.0));
      	}
      	return tmp;
      }
      
      function code(x)
      	tmp = 0.0
      	if (x <= 1.0)
      		tmp = Float64(-6.0 / fma(sqrt(x), 4.0, 1.0));
      	else
      		tmp = Float64(1.5 * sqrt((x ^ -1.0)));
      	end
      	return tmp
      end
      
      code[x_] := If[LessEqual[x, 1.0], N[(-6.0 / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(1.5 * N[Sqrt[N[Power[x, -1.0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;x \leq 1:\\
      \;\;\;\;\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
      
      \mathbf{else}:\\
      \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if x < 1

        1. Initial program 99.8%

          \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
        4. Step-by-step derivation
          1. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
          2. +-commutativeN/A

            \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
          3. *-commutativeN/A

            \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
          4. lower-fma.f64N/A

            \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
          5. lower-sqrt.f6497.6

            \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
        5. Applied rewrites97.6%

          \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]

        if 1 < x

        1. Initial program 99.7%

          \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
        4. Step-by-step derivation
          1. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
          2. +-commutativeN/A

            \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
          3. *-commutativeN/A

            \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
          4. lower-fma.f64N/A

            \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
          5. lower-sqrt.f641.9

            \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
        5. Applied rewrites1.9%

          \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
        6. Taylor expanded in x around -inf

          \[\leadsto \frac{3}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
        7. Step-by-step derivation
          1. Applied rewrites7.0%

            \[\leadsto 1.5 \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
        8. Recombined 2 regimes into one program.
        9. Final simplification54.1%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \]
        10. Add Preprocessing

        Alternative 4: 7.0% accurate, 0.3× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{-1.5}{\sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 1.0) (/ -1.5 (sqrt x)) (* 1.5 (sqrt (pow x -1.0)))))
        double code(double x) {
        	double tmp;
        	if (x <= 1.0) {
        		tmp = -1.5 / sqrt(x);
        	} else {
        		tmp = 1.5 * sqrt(pow(x, -1.0));
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= 1.0d0) then
                tmp = (-1.5d0) / sqrt(x)
            else
                tmp = 1.5d0 * sqrt((x ** (-1.0d0)))
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= 1.0) {
        		tmp = -1.5 / Math.sqrt(x);
        	} else {
        		tmp = 1.5 * Math.sqrt(Math.pow(x, -1.0));
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= 1.0:
        		tmp = -1.5 / math.sqrt(x)
        	else:
        		tmp = 1.5 * math.sqrt(math.pow(x, -1.0))
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= 1.0)
        		tmp = Float64(-1.5 / sqrt(x));
        	else
        		tmp = Float64(1.5 * sqrt((x ^ -1.0)));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= 1.0)
        		tmp = -1.5 / sqrt(x);
        	else
        		tmp = 1.5 * sqrt((x ^ -1.0));
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, 1.0], N[(-1.5 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(1.5 * N[Sqrt[N[Power[x, -1.0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 1:\\
        \;\;\;\;\frac{-1.5}{\sqrt{x}}\\
        
        \mathbf{else}:\\
        \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 1

          1. Initial program 99.8%

            \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
          4. Step-by-step derivation
            1. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
            2. +-commutativeN/A

              \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
            3. *-commutativeN/A

              \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
            4. lower-fma.f64N/A

              \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
            5. lower-sqrt.f6497.6

              \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
          5. Applied rewrites97.6%

            \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
          6. Taylor expanded in x around inf

            \[\leadsto \frac{-3}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
          7. Step-by-step derivation
            1. Applied rewrites7.1%

              \[\leadsto -1.5 \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
            2. Step-by-step derivation
              1. Applied rewrites7.1%

                \[\leadsto \color{blue}{\frac{-1.5}{\sqrt{x}}} \]

              if 1 < x

              1. Initial program 99.7%

                \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              2. Add Preprocessing
              3. Taylor expanded in x around 0

                \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
              4. Step-by-step derivation
                1. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
                2. +-commutativeN/A

                  \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
                3. *-commutativeN/A

                  \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
                4. lower-fma.f64N/A

                  \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                5. lower-sqrt.f641.9

                  \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
              5. Applied rewrites1.9%

                \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
              6. Taylor expanded in x around -inf

                \[\leadsto \frac{3}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
              7. Step-by-step derivation
                1. Applied rewrites7.0%

                  \[\leadsto 1.5 \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
              8. Recombined 2 regimes into one program.
              9. Final simplification7.0%

                \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{-1.5}{\sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;1.5 \cdot \sqrt{{x}^{-1}}\\ \end{array} \]
              10. Add Preprocessing

              Alternative 5: 97.4% accurate, 1.0× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.45:\\ \;\;\;\;\frac{6 \cdot \left(x - 1\right)}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\ \end{array} \end{array} \]
              (FPCore (x)
               :precision binary64
               (if (<= x 3.45)
                 (/ (* 6.0 (- x 1.0)) (fma (sqrt x) 4.0 1.0))
                 (/ (* 6.0 x) (fma 4.0 (sqrt x) (+ 1.0 x)))))
              double code(double x) {
              	double tmp;
              	if (x <= 3.45) {
              		tmp = (6.0 * (x - 1.0)) / fma(sqrt(x), 4.0, 1.0);
              	} else {
              		tmp = (6.0 * x) / fma(4.0, sqrt(x), (1.0 + x));
              	}
              	return tmp;
              }
              
              function code(x)
              	tmp = 0.0
              	if (x <= 3.45)
              		tmp = Float64(Float64(6.0 * Float64(x - 1.0)) / fma(sqrt(x), 4.0, 1.0));
              	else
              		tmp = Float64(Float64(6.0 * x) / fma(4.0, sqrt(x), Float64(1.0 + x)));
              	end
              	return tmp
              end
              
              code[x_] := If[LessEqual[x, 3.45], N[(N[(6.0 * N[(x - 1.0), $MachinePrecision]), $MachinePrecision] / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(N[(6.0 * x), $MachinePrecision] / N[(4.0 * N[Sqrt[x], $MachinePrecision] + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;x \leq 3.45:\\
              \;\;\;\;\frac{6 \cdot \left(x - 1\right)}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if x < 3.4500000000000002

                1. Initial program 99.8%

                  \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                2. Add Preprocessing
                3. Taylor expanded in x around 0

                  \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\color{blue}{1 + 4 \cdot \sqrt{x}}} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
                  2. *-commutativeN/A

                    \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
                  3. lower-fma.f64N/A

                    \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                  4. lower-sqrt.f6497.1

                    \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
                5. Applied rewrites97.1%

                  \[\leadsto \frac{6 \cdot \left(x - 1\right)}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]

                if 3.4500000000000002 < x

                1. Initial program 99.7%

                  \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                2. Add Preprocessing
                3. Taylor expanded in x around inf

                  \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                4. Step-by-step derivation
                  1. lower-*.f6498.3

                    \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                5. Applied rewrites98.3%

                  \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                6. Step-by-step derivation
                  1. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                  2. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(x + 1\right)} + 4 \cdot \sqrt{x}} \]
                  3. +-commutativeN/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(1 + x\right)} + 4 \cdot \sqrt{x}} \]
                  4. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(1 + x\right)} + 4 \cdot \sqrt{x}} \]
                  5. +-commutativeN/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{4 \cdot \sqrt{x} + \left(1 + x\right)}} \]
                  6. lift-*.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{4 \cdot \sqrt{x}} + \left(1 + x\right)} \]
                  7. lower-fma.f6498.3

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}} \]
                7. Applied rewrites98.3%

                  \[\leadsto \color{blue}{\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}} \]
              3. Recombined 2 regimes into one program.
              4. Final simplification97.7%

                \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.45:\\ \;\;\;\;\frac{6 \cdot \left(x - 1\right)}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\ \end{array} \]
              5. Add Preprocessing

              Alternative 6: 97.4% accurate, 1.0× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.45:\\ \;\;\;\;\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\ \end{array} \end{array} \]
              (FPCore (x)
               :precision binary64
               (if (<= x 3.45)
                 (* (- x 1.0) (/ 6.0 (fma (sqrt x) 4.0 1.0)))
                 (/ (* 6.0 x) (fma 4.0 (sqrt x) (+ 1.0 x)))))
              double code(double x) {
              	double tmp;
              	if (x <= 3.45) {
              		tmp = (x - 1.0) * (6.0 / fma(sqrt(x), 4.0, 1.0));
              	} else {
              		tmp = (6.0 * x) / fma(4.0, sqrt(x), (1.0 + x));
              	}
              	return tmp;
              }
              
              function code(x)
              	tmp = 0.0
              	if (x <= 3.45)
              		tmp = Float64(Float64(x - 1.0) * Float64(6.0 / fma(sqrt(x), 4.0, 1.0)));
              	else
              		tmp = Float64(Float64(6.0 * x) / fma(4.0, sqrt(x), Float64(1.0 + x)));
              	end
              	return tmp
              end
              
              code[x_] := If[LessEqual[x, 3.45], N[(N[(x - 1.0), $MachinePrecision] * N[(6.0 / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(6.0 * x), $MachinePrecision] / N[(4.0 * N[Sqrt[x], $MachinePrecision] + N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;x \leq 3.45:\\
              \;\;\;\;\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if x < 3.4500000000000002

                1. Initial program 99.8%

                  \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                  2. lift-*.f64N/A

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

                    \[\leadsto \color{blue}{6 \cdot \frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                  4. *-commutativeN/A

                    \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                  5. lower-*.f64N/A

                    \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                  6. lower-/.f6499.8

                    \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                  7. lift-+.f64N/A

                    \[\leadsto \frac{x - 1}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                  8. +-commutativeN/A

                    \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + \left(x + 1\right)}} \cdot 6 \]
                  9. lift-*.f64N/A

                    \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x}} + \left(x + 1\right)} \cdot 6 \]
                  10. *-commutativeN/A

                    \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + \left(x + 1\right)} \cdot 6 \]
                  11. lower-fma.f6499.8

                    \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x + 1\right)}} \cdot 6 \]
                  12. lift-+.f64N/A

                    \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{x + 1}\right)} \cdot 6 \]
                  13. +-commutativeN/A

                    \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
                  14. lower-+.f6499.8

                    \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
                4. Applied rewrites99.8%

                  \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)} \cdot 6} \]
                5. Taylor expanded in x around 0

                  \[\leadsto \frac{x - 1}{\color{blue}{1 + 4 \cdot \sqrt{x}}} \cdot 6 \]
                6. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + 1}} \cdot 6 \]
                  2. *-commutativeN/A

                    \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + 1} \cdot 6 \]
                  3. lower-fma.f64N/A

                    \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
                  4. lower-sqrt.f6497.1

                    \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \cdot 6 \]
                7. Applied rewrites97.1%

                  \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
                8. Step-by-step derivation
                  1. lift-*.f64N/A

                    \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)} \cdot 6} \]
                  2. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
                  3. associate-*l/N/A

                    \[\leadsto \color{blue}{\frac{\left(x - 1\right) \cdot 6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                  4. associate-/l*N/A

                    \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                  5. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                  6. lower-/.f6497.1

                    \[\leadsto \left(x - 1\right) \cdot \color{blue}{\frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                9. Applied rewrites97.1%

                  \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]

                if 3.4500000000000002 < x

                1. Initial program 99.7%

                  \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                2. Add Preprocessing
                3. Taylor expanded in x around inf

                  \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                4. Step-by-step derivation
                  1. lower-*.f6498.3

                    \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                5. Applied rewrites98.3%

                  \[\leadsto \frac{\color{blue}{6 \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                6. Step-by-step derivation
                  1. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                  2. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(x + 1\right)} + 4 \cdot \sqrt{x}} \]
                  3. +-commutativeN/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(1 + x\right)} + 4 \cdot \sqrt{x}} \]
                  4. lift-+.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\left(1 + x\right)} + 4 \cdot \sqrt{x}} \]
                  5. +-commutativeN/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{4 \cdot \sqrt{x} + \left(1 + x\right)}} \]
                  6. lift-*.f64N/A

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{4 \cdot \sqrt{x}} + \left(1 + x\right)} \]
                  7. lower-fma.f6498.3

                    \[\leadsto \frac{6 \cdot x}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}} \]
                7. Applied rewrites98.3%

                  \[\leadsto \color{blue}{\frac{6 \cdot x}{\mathsf{fma}\left(4, \sqrt{x}, 1 + x\right)}} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 7: 99.9% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1} \end{array} \]
              (FPCore (x)
               :precision binary64
               (* (- x 1.0) (/ 6.0 (+ (fma (sqrt x) 4.0 x) 1.0))))
              double code(double x) {
              	return (x - 1.0) * (6.0 / (fma(sqrt(x), 4.0, x) + 1.0));
              }
              
              function code(x)
              	return Float64(Float64(x - 1.0) * Float64(6.0 / Float64(fma(sqrt(x), 4.0, x) + 1.0)))
              end
              
              code[x_] := N[(N[(x - 1.0), $MachinePrecision] * N[(6.0 / N[(N[(N[Sqrt[x], $MachinePrecision] * 4.0 + x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1}
              \end{array}
              
              Derivation
              1. Initial program 99.8%

                \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                2. lift-*.f64N/A

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

                  \[\leadsto \color{blue}{6 \cdot \frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                4. *-commutativeN/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                5. lower-*.f64N/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                6. lower-/.f6499.9

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                7. lift-+.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                8. +-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + \left(x + 1\right)}} \cdot 6 \]
                9. lift-*.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x}} + \left(x + 1\right)} \cdot 6 \]
                10. *-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + \left(x + 1\right)} \cdot 6 \]
                11. lower-fma.f6499.9

                  \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x + 1\right)}} \cdot 6 \]
                12. lift-+.f64N/A

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{x + 1}\right)} \cdot 6 \]
                13. +-commutativeN/A

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
                14. lower-+.f6499.9

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
              4. Applied rewrites99.9%

                \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)} \cdot 6} \]
              5. Step-by-step derivation
                1. lift-fma.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4 + \left(1 + x\right)}} \cdot 6 \]
                2. lift-+.f64N/A

                  \[\leadsto \frac{x - 1}{\sqrt{x} \cdot 4 + \color{blue}{\left(1 + x\right)}} \cdot 6 \]
                3. +-commutativeN/A

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

                  \[\leadsto \frac{x - 1}{\color{blue}{\left(\sqrt{x} \cdot 4 + x\right) + 1}} \cdot 6 \]
                5. lower-+.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\left(\sqrt{x} \cdot 4 + x\right) + 1}} \cdot 6 \]
                6. *-commutativeN/A

                  \[\leadsto \frac{x - 1}{\left(\color{blue}{4 \cdot \sqrt{x}} + x\right) + 1} \cdot 6 \]
                7. lower-fma.f6499.9

                  \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right)} + 1} \cdot 6 \]
              6. Applied rewrites99.9%

                \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \cdot 6 \]
              7. Step-by-step derivation
                1. lift-*.f64N/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1} \cdot 6} \]
                2. lift-/.f64N/A

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

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

                  \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \]
                5. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \]
                6. lower-/.f6499.8

                  \[\leadsto \left(x - 1\right) \cdot \color{blue}{\frac{6}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \]
                7. lift-fma.f64N/A

                  \[\leadsto \left(x - 1\right) \cdot \frac{6}{\color{blue}{\left(4 \cdot \sqrt{x} + x\right)} + 1} \]
                8. *-commutativeN/A

                  \[\leadsto \left(x - 1\right) \cdot \frac{6}{\left(\color{blue}{\sqrt{x} \cdot 4} + x\right) + 1} \]
                9. lower-fma.f6499.8

                  \[\leadsto \left(x - 1\right) \cdot \frac{6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x\right)} + 1} \]
              8. Applied rewrites99.8%

                \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1}} \]
              9. Add Preprocessing

              Alternative 8: 99.7% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1} \end{array} \]
              (FPCore (x)
               :precision binary64
               (/ (fma 6.0 x -6.0) (+ (fma (sqrt x) 4.0 x) 1.0)))
              double code(double x) {
              	return fma(6.0, x, -6.0) / (fma(sqrt(x), 4.0, x) + 1.0);
              }
              
              function code(x)
              	return Float64(fma(6.0, x, -6.0) / Float64(fma(sqrt(x), 4.0, x) + 1.0))
              end
              
              code[x_] := N[(N[(6.0 * x + -6.0), $MachinePrecision] / N[(N[(N[Sqrt[x], $MachinePrecision] * 4.0 + x), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1}
              \end{array}
              
              Derivation
              1. Initial program 99.8%

                \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              2. Add Preprocessing
              3. Taylor expanded in x around inf

                \[\leadsto \frac{\color{blue}{x \cdot \left(6 - 6 \cdot \frac{1}{x}\right)}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              4. Step-by-step derivation
                1. fp-cancel-sub-sign-invN/A

                  \[\leadsto \frac{x \cdot \color{blue}{\left(6 + \left(\mathsf{neg}\left(6\right)\right) \cdot \frac{1}{x}\right)}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                2. distribute-rgt-inN/A

                  \[\leadsto \frac{\color{blue}{6 \cdot x + \left(\left(\mathsf{neg}\left(6\right)\right) \cdot \frac{1}{x}\right) \cdot x}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                3. metadata-evalN/A

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

                  \[\leadsto \frac{6 \cdot x + \color{blue}{-6 \cdot \left(\frac{1}{x} \cdot x\right)}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                5. lft-mult-inverseN/A

                  \[\leadsto \frac{6 \cdot x + -6 \cdot \color{blue}{1}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                6. metadata-evalN/A

                  \[\leadsto \frac{6 \cdot x + \color{blue}{-6}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
                7. lower-fma.f6499.8

                  \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(6, x, -6\right)}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              5. Applied rewrites99.8%

                \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(6, x, -6\right)}}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              6. Step-by-step derivation
                1. lift-+.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                2. +-commutativeN/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{4 \cdot \sqrt{x} + \left(x + 1\right)}} \]
                3. lift-+.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{4 \cdot \sqrt{x} + \color{blue}{\left(x + 1\right)}} \]
                4. associate-+l+N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\left(4 \cdot \sqrt{x} + x\right) + 1}} \]
                5. lift-*.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\left(\color{blue}{4 \cdot \sqrt{x}} + x\right) + 1} \]
                6. lift-fma.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right)} + 1} \]
                7. lift-+.f6499.8

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\mathsf{fma}\left(4, \sqrt{x}, x\right) + 1}} \]
                8. lift-fma.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\left(4 \cdot \sqrt{x} + x\right)} + 1} \]
                9. *-commutativeN/A

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\left(\color{blue}{\sqrt{x} \cdot 4} + x\right) + 1} \]
                10. lower-fma.f6499.8

                  \[\leadsto \frac{\mathsf{fma}\left(6, x, -6\right)}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x\right)} + 1} \]
              7. Applied rewrites99.8%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(6, x, -6\right)}{\mathsf{fma}\left(\sqrt{x}, 4, x\right) + 1}} \]
              8. Add Preprocessing

              Alternative 9: 51.7% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)} \end{array} \]
              (FPCore (x) :precision binary64 (* (- x 1.0) (/ 6.0 (fma (sqrt x) 4.0 1.0))))
              double code(double x) {
              	return (x - 1.0) * (6.0 / fma(sqrt(x), 4.0, 1.0));
              }
              
              function code(x)
              	return Float64(Float64(x - 1.0) * Float64(6.0 / fma(sqrt(x), 4.0, 1.0)))
              end
              
              code[x_] := N[(N[(x - 1.0), $MachinePrecision] * N[(6.0 / N[(N[Sqrt[x], $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}
              \end{array}
              
              Derivation
              1. Initial program 99.8%

                \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                2. lift-*.f64N/A

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

                  \[\leadsto \color{blue}{6 \cdot \frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \]
                4. *-commutativeN/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                5. lower-*.f64N/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \cdot 6} \]
                6. lower-/.f6499.9

                  \[\leadsto \color{blue}{\frac{x - 1}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                7. lift-+.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\left(x + 1\right) + 4 \cdot \sqrt{x}}} \cdot 6 \]
                8. +-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + \left(x + 1\right)}} \cdot 6 \]
                9. lift-*.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x}} + \left(x + 1\right)} \cdot 6 \]
                10. *-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + \left(x + 1\right)} \cdot 6 \]
                11. lower-fma.f6499.9

                  \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, x + 1\right)}} \cdot 6 \]
                12. lift-+.f64N/A

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{x + 1}\right)} \cdot 6 \]
                13. +-commutativeN/A

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
                14. lower-+.f6499.9

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, \color{blue}{1 + x}\right)} \cdot 6 \]
              4. Applied rewrites99.9%

                \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1 + x\right)} \cdot 6} \]
              5. Taylor expanded in x around 0

                \[\leadsto \frac{x - 1}{\color{blue}{1 + 4 \cdot \sqrt{x}}} \cdot 6 \]
              6. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{4 \cdot \sqrt{x} + 1}} \cdot 6 \]
                2. *-commutativeN/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\sqrt{x} \cdot 4} + 1} \cdot 6 \]
                3. lower-fma.f64N/A

                  \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
                4. lower-sqrt.f6454.2

                  \[\leadsto \frac{x - 1}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \cdot 6 \]
              7. Applied rewrites54.2%

                \[\leadsto \frac{x - 1}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
              8. Step-by-step derivation
                1. lift-*.f64N/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)} \cdot 6} \]
                2. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{x - 1}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \cdot 6 \]
                3. associate-*l/N/A

                  \[\leadsto \color{blue}{\frac{\left(x - 1\right) \cdot 6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                4. associate-/l*N/A

                  \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                5. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                6. lower-/.f6454.2

                  \[\leadsto \left(x - 1\right) \cdot \color{blue}{\frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
              9. Applied rewrites54.2%

                \[\leadsto \color{blue}{\left(x - 1\right) \cdot \frac{6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
              10. Add Preprocessing

              Alternative 10: 4.4% accurate, 1.9× speedup?

              \[\begin{array}{l} \\ \frac{-1.5}{\sqrt{x}} \end{array} \]
              (FPCore (x) :precision binary64 (/ -1.5 (sqrt x)))
              double code(double x) {
              	return -1.5 / sqrt(x);
              }
              
              real(8) function code(x)
                  real(8), intent (in) :: x
                  code = (-1.5d0) / sqrt(x)
              end function
              
              public static double code(double x) {
              	return -1.5 / Math.sqrt(x);
              }
              
              def code(x):
              	return -1.5 / math.sqrt(x)
              
              function code(x)
              	return Float64(-1.5 / sqrt(x))
              end
              
              function tmp = code(x)
              	tmp = -1.5 / sqrt(x);
              end
              
              code[x_] := N[(-1.5 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{-1.5}{\sqrt{x}}
              \end{array}
              
              Derivation
              1. Initial program 99.8%

                \[\frac{6 \cdot \left(x - 1\right)}{\left(x + 1\right) + 4 \cdot \sqrt{x}} \]
              2. Add Preprocessing
              3. Taylor expanded in x around 0

                \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
              4. Step-by-step derivation
                1. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{-6}{1 + 4 \cdot \sqrt{x}}} \]
                2. +-commutativeN/A

                  \[\leadsto \frac{-6}{\color{blue}{4 \cdot \sqrt{x} + 1}} \]
                3. *-commutativeN/A

                  \[\leadsto \frac{-6}{\color{blue}{\sqrt{x} \cdot 4} + 1} \]
                4. lower-fma.f64N/A

                  \[\leadsto \frac{-6}{\color{blue}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
                5. lower-sqrt.f6451.6

                  \[\leadsto \frac{-6}{\mathsf{fma}\left(\color{blue}{\sqrt{x}}, 4, 1\right)} \]
              5. Applied rewrites51.6%

                \[\leadsto \color{blue}{\frac{-6}{\mathsf{fma}\left(\sqrt{x}, 4, 1\right)}} \]
              6. Taylor expanded in x around inf

                \[\leadsto \frac{-3}{2} \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
              7. Step-by-step derivation
                1. Applied rewrites4.6%

                  \[\leadsto -1.5 \cdot \color{blue}{\sqrt{\frac{1}{x}}} \]
                2. Step-by-step derivation
                  1. Applied rewrites4.6%

                    \[\leadsto \color{blue}{\frac{-1.5}{\sqrt{x}}} \]
                  2. Add Preprocessing

                  Developer Target 1: 99.9% accurate, 0.9× speedup?

                  \[\begin{array}{l} \\ \frac{6}{\frac{\left(x + 1\right) + 4 \cdot \sqrt{x}}{x - 1}} \end{array} \]
                  (FPCore (x)
                   :precision binary64
                   (/ 6.0 (/ (+ (+ x 1.0) (* 4.0 (sqrt x))) (- x 1.0))))
                  double code(double x) {
                  	return 6.0 / (((x + 1.0) + (4.0 * sqrt(x))) / (x - 1.0));
                  }
                  
                  real(8) function code(x)
                      real(8), intent (in) :: x
                      code = 6.0d0 / (((x + 1.0d0) + (4.0d0 * sqrt(x))) / (x - 1.0d0))
                  end function
                  
                  public static double code(double x) {
                  	return 6.0 / (((x + 1.0) + (4.0 * Math.sqrt(x))) / (x - 1.0));
                  }
                  
                  def code(x):
                  	return 6.0 / (((x + 1.0) + (4.0 * math.sqrt(x))) / (x - 1.0))
                  
                  function code(x)
                  	return Float64(6.0 / Float64(Float64(Float64(x + 1.0) + Float64(4.0 * sqrt(x))) / Float64(x - 1.0)))
                  end
                  
                  function tmp = code(x)
                  	tmp = 6.0 / (((x + 1.0) + (4.0 * sqrt(x))) / (x - 1.0));
                  end
                  
                  code[x_] := N[(6.0 / N[(N[(N[(x + 1.0), $MachinePrecision] + N[(4.0 * N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{6}{\frac{\left(x + 1\right) + 4 \cdot \sqrt{x}}{x - 1}}
                  \end{array}
                  

                  Reproduce

                  ?
                  herbie shell --seed 2024338 
                  (FPCore (x)
                    :name "Data.Approximate.Numerics:blog from approximate-0.2.2.1"
                    :precision binary64
                  
                    :alt
                    (! :herbie-platform default (/ 6 (/ (+ (+ x 1) (* 4 (sqrt x))) (- x 1))))
                  
                    (/ (* 6.0 (- x 1.0)) (+ (+ x 1.0) (* 4.0 (sqrt x)))))