Main:bigenough3 from C

Percentage Accurate: 53.9% → 99.7%
Time: 8.1s
Alternatives: 8
Speedup: 2.0×

Specification

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

\\
\sqrt{x + 1} - \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 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: 53.9% accurate, 1.0× speedup?

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

\\
\sqrt{x + 1} - \sqrt{x}
\end{array}

Alternative 1: 99.7% accurate, 1.0× speedup?

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

\\
\frac{1}{\sqrt{1 + x} + \sqrt{x}}
\end{array}
Derivation
  1. Initial program 46.8%

    \[\sqrt{x + 1} - \sqrt{x} \]
  2. Step-by-step derivation
    1. flip--46.9%

      \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
    2. div-inv46.9%

      \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    3. add-sqr-sqrt47.3%

      \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    4. add-sqr-sqrt48.1%

      \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    5. associate--l+48.1%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
  3. Applied egg-rr48.1%

    \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
  4. Step-by-step derivation
    1. +-commutative48.1%

      \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    2. associate-+l-99.7%

      \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. +-inverses99.7%

      \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    4. metadata-eval99.7%

      \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    5. associate-*r/99.7%

      \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
    6. metadata-eval99.7%

      \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
    7. +-commutative99.7%

      \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
  5. Simplified99.7%

    \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
  6. Final simplification99.7%

    \[\leadsto \frac{1}{\sqrt{1 + x} + \sqrt{x}} \]

Alternative 2: 99.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{1 + x} - \sqrt{x}\\ \mathbf{if}\;t_0 \leq 4 \cdot 10^{-6}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (- (sqrt (+ 1.0 x)) (sqrt x))))
   (if (<= t_0 4e-6) (* (pow x -0.5) 0.5) t_0)))
double code(double x) {
	double t_0 = sqrt((1.0 + x)) - sqrt(x);
	double tmp;
	if (t_0 <= 4e-6) {
		tmp = pow(x, -0.5) * 0.5;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sqrt((1.0d0 + x)) - sqrt(x)
    if (t_0 <= 4d-6) then
        tmp = (x ** (-0.5d0)) * 0.5d0
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = Math.sqrt((1.0 + x)) - Math.sqrt(x);
	double tmp;
	if (t_0 <= 4e-6) {
		tmp = Math.pow(x, -0.5) * 0.5;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = math.sqrt((1.0 + x)) - math.sqrt(x)
	tmp = 0
	if t_0 <= 4e-6:
		tmp = math.pow(x, -0.5) * 0.5
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(sqrt(Float64(1.0 + x)) - sqrt(x))
	tmp = 0.0
	if (t_0 <= 4e-6)
		tmp = Float64((x ^ -0.5) * 0.5);
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = sqrt((1.0 + x)) - sqrt(x);
	tmp = 0.0;
	if (t_0 <= 4e-6)
		tmp = (x ^ -0.5) * 0.5;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 4e-6], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{1 + x} - \sqrt{x}\\
\mathbf{if}\;t_0 \leq 4 \cdot 10^{-6}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\

\mathbf{else}:\\
\;\;\;\;t_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x)) < 3.99999999999999982e-6

    1. Initial program 5.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--4.9%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv4.9%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt5.7%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.2%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.2%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.2%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.2%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+66.7%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num66.8%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.0%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.2%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.2%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 99.0%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative99.0%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified99.0%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. associate-/r*99.0%

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{x}}}{2}} \]
      2. div-inv99.0%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} \cdot \frac{1}{2}} \]
      3. pow1/299.0%

        \[\leadsto \frac{1}{\color{blue}{{x}^{0.5}}} \cdot \frac{1}{2} \]
      4. pow-flip99.5%

        \[\leadsto \color{blue}{{x}^{\left(-0.5\right)}} \cdot \frac{1}{2} \]
      5. metadata-eval99.5%

        \[\leadsto {x}^{\color{blue}{-0.5}} \cdot \frac{1}{2} \]
      6. metadata-eval99.5%

        \[\leadsto {x}^{-0.5} \cdot \color{blue}{0.5} \]
    12. Applied egg-rr99.5%

      \[\leadsto \color{blue}{{x}^{-0.5} \cdot 0.5} \]

    if 3.99999999999999982e-6 < (-.f64 (sqrt.f64 (+.f64 x 1)) (sqrt.f64 x))

    1. Initial program 99.8%

      \[\sqrt{x + 1} - \sqrt{x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\sqrt{1 + x} - \sqrt{x} \leq 4 \cdot 10^{-6}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\sqrt{1 + x} - \sqrt{x}\\ \end{array} \]

Alternative 3: 98.8% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.25:\\ \;\;\;\;\left(1 + x \cdot \left(0.5 + x \cdot -0.125\right)\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.25)
   (- (+ 1.0 (* x (+ 0.5 (* x -0.125)))) (sqrt x))
   (* (pow x -0.5) 0.5)))
double code(double x) {
	double tmp;
	if (x <= 1.25) {
		tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - sqrt(x);
	} else {
		tmp = pow(x, -0.5) * 0.5;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.25d0) then
        tmp = (1.0d0 + (x * (0.5d0 + (x * (-0.125d0))))) - sqrt(x)
    else
        tmp = (x ** (-0.5d0)) * 0.5d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.25) {
		tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - Math.sqrt(x);
	} else {
		tmp = Math.pow(x, -0.5) * 0.5;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.25:
		tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - math.sqrt(x)
	else:
		tmp = math.pow(x, -0.5) * 0.5
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.25)
		tmp = Float64(Float64(1.0 + Float64(x * Float64(0.5 + Float64(x * -0.125)))) - sqrt(x));
	else
		tmp = Float64((x ^ -0.5) * 0.5);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.25)
		tmp = (1.0 + (x * (0.5 + (x * -0.125)))) - sqrt(x);
	else
		tmp = (x ^ -0.5) * 0.5;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.25], N[(N[(1.0 + N[(x * N[(0.5 + N[(x * -0.125), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.25:\\
\;\;\;\;\left(1 + x \cdot \left(0.5 + x \cdot -0.125\right)\right) - \sqrt{x}\\

\mathbf{else}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.25

    1. Initial program 100.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Taylor expanded in x around 0 99.6%

      \[\leadsto \color{blue}{\left(1 + \left(-0.125 \cdot {x}^{2} + 0.5 \cdot x\right)\right)} - \sqrt{x} \]
    3. Step-by-step derivation
      1. +-commutative99.6%

        \[\leadsto \left(1 + \color{blue}{\left(0.5 \cdot x + -0.125 \cdot {x}^{2}\right)}\right) - \sqrt{x} \]
      2. unpow299.6%

        \[\leadsto \left(1 + \left(0.5 \cdot x + -0.125 \cdot \color{blue}{\left(x \cdot x\right)}\right)\right) - \sqrt{x} \]
      3. associate-*r*99.6%

        \[\leadsto \left(1 + \left(0.5 \cdot x + \color{blue}{\left(-0.125 \cdot x\right) \cdot x}\right)\right) - \sqrt{x} \]
      4. distribute-rgt-out99.6%

        \[\leadsto \left(1 + \color{blue}{x \cdot \left(0.5 + -0.125 \cdot x\right)}\right) - \sqrt{x} \]
      5. *-commutative99.6%

        \[\leadsto \left(1 + x \cdot \left(0.5 + \color{blue}{x \cdot -0.125}\right)\right) - \sqrt{x} \]
    4. Simplified99.6%

      \[\leadsto \color{blue}{\left(1 + x \cdot \left(0.5 + x \cdot -0.125\right)\right)} - \sqrt{x} \]

    if 1.25 < x

    1. Initial program 5.5%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--5.6%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv5.6%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt6.3%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.8%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.8%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.8%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.8%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.7%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 98.7%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified98.7%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. associate-/r*98.7%

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{x}}}{2}} \]
      2. div-inv98.7%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} \cdot \frac{1}{2}} \]
      3. pow1/298.7%

        \[\leadsto \frac{1}{\color{blue}{{x}^{0.5}}} \cdot \frac{1}{2} \]
      4. pow-flip99.2%

        \[\leadsto \color{blue}{{x}^{\left(-0.5\right)}} \cdot \frac{1}{2} \]
      5. metadata-eval99.2%

        \[\leadsto {x}^{\color{blue}{-0.5}} \cdot \frac{1}{2} \]
      6. metadata-eval99.2%

        \[\leadsto {x}^{-0.5} \cdot \color{blue}{0.5} \]
    12. Applied egg-rr99.2%

      \[\leadsto \color{blue}{{x}^{-0.5} \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.25:\\ \;\;\;\;\left(1 + x \cdot \left(0.5 + x \cdot -0.125\right)\right) - \sqrt{x}\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \]

Alternative 4: 98.6% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;1 + \left(x \cdot 0.5 - \sqrt{x}\right)\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.0) (+ 1.0 (- (* x 0.5) (sqrt x))) (* (pow x -0.5) 0.5)))
double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 1.0 + ((x * 0.5) - sqrt(x));
	} else {
		tmp = pow(x, -0.5) * 0.5;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.0d0) then
        tmp = 1.0d0 + ((x * 0.5d0) - sqrt(x))
    else
        tmp = (x ** (-0.5d0)) * 0.5d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 1.0 + ((x * 0.5) - Math.sqrt(x));
	} else {
		tmp = Math.pow(x, -0.5) * 0.5;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.0:
		tmp = 1.0 + ((x * 0.5) - math.sqrt(x))
	else:
		tmp = math.pow(x, -0.5) * 0.5
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.0)
		tmp = Float64(1.0 + Float64(Float64(x * 0.5) - sqrt(x)));
	else
		tmp = Float64((x ^ -0.5) * 0.5);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.0)
		tmp = 1.0 + ((x * 0.5) - sqrt(x));
	else
		tmp = (x ^ -0.5) * 0.5;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.0], N[(1.0 + N[(N[(x * 0.5), $MachinePrecision] - N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;1 + \left(x \cdot 0.5 - \sqrt{x}\right)\\

\mathbf{else}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\


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

    1. Initial program 100.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Taylor expanded in x around 0 99.3%

      \[\leadsto \color{blue}{\left(1 + 0.5 \cdot x\right)} - \sqrt{x} \]
    3. Step-by-step derivation
      1. associate--l+99.4%

        \[\leadsto \color{blue}{1 + \left(0.5 \cdot x - \sqrt{x}\right)} \]
      2. +-commutative99.4%

        \[\leadsto \color{blue}{\left(0.5 \cdot x - \sqrt{x}\right) + 1} \]
      3. *-commutative99.4%

        \[\leadsto \left(\color{blue}{x \cdot 0.5} - \sqrt{x}\right) + 1 \]
    4. Applied egg-rr99.4%

      \[\leadsto \color{blue}{\left(x \cdot 0.5 - \sqrt{x}\right) + 1} \]

    if 1 < x

    1. Initial program 5.5%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--5.6%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv5.6%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt6.3%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.8%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.8%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.8%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.8%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.7%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 98.7%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified98.7%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. associate-/r*98.7%

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{x}}}{2}} \]
      2. div-inv98.7%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} \cdot \frac{1}{2}} \]
      3. pow1/298.7%

        \[\leadsto \frac{1}{\color{blue}{{x}^{0.5}}} \cdot \frac{1}{2} \]
      4. pow-flip99.2%

        \[\leadsto \color{blue}{{x}^{\left(-0.5\right)}} \cdot \frac{1}{2} \]
      5. metadata-eval99.2%

        \[\leadsto {x}^{\color{blue}{-0.5}} \cdot \frac{1}{2} \]
      6. metadata-eval99.2%

        \[\leadsto {x}^{-0.5} \cdot \color{blue}{0.5} \]
    12. Applied egg-rr99.2%

      \[\leadsto \color{blue}{{x}^{-0.5} \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;1 + \left(x \cdot 0.5 - \sqrt{x}\right)\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \]

Alternative 5: 98.0% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{1}{1 + \sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.0) (/ 1.0 (+ 1.0 (sqrt x))) (* (pow x -0.5) 0.5)))
double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 1.0 / (1.0 + sqrt(x));
	} else {
		tmp = pow(x, -0.5) * 0.5;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.0d0) then
        tmp = 1.0d0 / (1.0d0 + sqrt(x))
    else
        tmp = (x ** (-0.5d0)) * 0.5d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 1.0 / (1.0 + Math.sqrt(x));
	} else {
		tmp = Math.pow(x, -0.5) * 0.5;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.0:
		tmp = 1.0 / (1.0 + math.sqrt(x))
	else:
		tmp = math.pow(x, -0.5) * 0.5
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.0)
		tmp = Float64(1.0 / Float64(1.0 + sqrt(x)));
	else
		tmp = Float64((x ^ -0.5) * 0.5);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.0)
		tmp = 1.0 / (1.0 + sqrt(x));
	else
		tmp = (x ^ -0.5) * 0.5;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.0], N[(1.0 / N[(1.0 + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;\frac{1}{1 + \sqrt{x}}\\

\mathbf{else}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\


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

    1. Initial program 100.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--99.9%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv99.9%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt99.9%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt99.9%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+99.9%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr99.9%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative99.9%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.9%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.9%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.9%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.9%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.9%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.9%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.9%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. +-commutative99.9%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} + \sqrt{1 + x}}} \]
      2. add-sqr-sqrt99.9%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{\sqrt{x}} \cdot \sqrt{\sqrt{x}}} + \sqrt{1 + x}} \]
      3. fma-def99.9%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\sqrt{\sqrt{x}}, \sqrt{\sqrt{x}}, \sqrt{1 + x}\right)}} \]
      4. pow1/299.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left(\sqrt{\color{blue}{{x}^{0.5}}}, \sqrt{\sqrt{x}}, \sqrt{1 + x}\right)} \]
      5. sqrt-pow199.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{{x}^{\left(\frac{0.5}{2}\right)}}, \sqrt{\sqrt{x}}, \sqrt{1 + x}\right)} \]
      6. metadata-eval99.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left({x}^{\color{blue}{0.25}}, \sqrt{\sqrt{x}}, \sqrt{1 + x}\right)} \]
      7. pow1/299.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left({x}^{0.25}, \sqrt{\color{blue}{{x}^{0.5}}}, \sqrt{1 + x}\right)} \]
      8. sqrt-pow199.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left({x}^{0.25}, \color{blue}{{x}^{\left(\frac{0.5}{2}\right)}}, \sqrt{1 + x}\right)} \]
      9. metadata-eval99.9%

        \[\leadsto \frac{1}{\mathsf{fma}\left({x}^{0.25}, {x}^{\color{blue}{0.25}}, \sqrt{1 + x}\right)} \]
    7. Applied egg-rr99.9%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left({x}^{0.25}, {x}^{0.25}, \sqrt{1 + x}\right)}} \]
    8. Taylor expanded in x around 0 97.9%

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

    if 1 < x

    1. Initial program 5.5%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--5.6%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv5.6%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt6.3%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.8%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.8%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.8%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.8%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.7%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 98.7%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified98.7%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. associate-/r*98.7%

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{x}}}{2}} \]
      2. div-inv98.7%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} \cdot \frac{1}{2}} \]
      3. pow1/298.7%

        \[\leadsto \frac{1}{\color{blue}{{x}^{0.5}}} \cdot \frac{1}{2} \]
      4. pow-flip99.2%

        \[\leadsto \color{blue}{{x}^{\left(-0.5\right)}} \cdot \frac{1}{2} \]
      5. metadata-eval99.2%

        \[\leadsto {x}^{\color{blue}{-0.5}} \cdot \frac{1}{2} \]
      6. metadata-eval99.2%

        \[\leadsto {x}^{-0.5} \cdot \color{blue}{0.5} \]
    12. Applied egg-rr99.2%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;\frac{1}{1 + \sqrt{x}}\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \]

Alternative 6: 96.8% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.25:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 0.25) 1.0 (* (pow x -0.5) 0.5)))
double code(double x) {
	double tmp;
	if (x <= 0.25) {
		tmp = 1.0;
	} else {
		tmp = pow(x, -0.5) * 0.5;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 0.25d0) then
        tmp = 1.0d0
    else
        tmp = (x ** (-0.5d0)) * 0.5d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 0.25) {
		tmp = 1.0;
	} else {
		tmp = Math.pow(x, -0.5) * 0.5;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 0.25:
		tmp = 1.0
	else:
		tmp = math.pow(x, -0.5) * 0.5
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 0.25)
		tmp = 1.0;
	else
		tmp = Float64((x ^ -0.5) * 0.5);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 0.25)
		tmp = 1.0;
	else
		tmp = (x ^ -0.5) * 0.5;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 0.25], 1.0, N[(N[Power[x, -0.5], $MachinePrecision] * 0.5), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.25:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;{x}^{-0.5} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.25

    1. Initial program 100.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Taylor expanded in x around 0 95.6%

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

    if 0.25 < x

    1. Initial program 5.5%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--5.6%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv5.6%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt6.3%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.8%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.8%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.8%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.8%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.7%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 98.7%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified98.7%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. associate-/r*98.7%

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{x}}}{2}} \]
      2. div-inv98.7%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} \cdot \frac{1}{2}} \]
      3. pow1/298.7%

        \[\leadsto \frac{1}{\color{blue}{{x}^{0.5}}} \cdot \frac{1}{2} \]
      4. pow-flip99.2%

        \[\leadsto \color{blue}{{x}^{\left(-0.5\right)}} \cdot \frac{1}{2} \]
      5. metadata-eval99.2%

        \[\leadsto {x}^{\color{blue}{-0.5}} \cdot \frac{1}{2} \]
      6. metadata-eval99.2%

        \[\leadsto {x}^{-0.5} \cdot \color{blue}{0.5} \]
    12. Applied egg-rr99.2%

      \[\leadsto \color{blue}{{x}^{-0.5} \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.25:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;{x}^{-0.5} \cdot 0.5\\ \end{array} \]

Alternative 7: 96.7% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.25:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{0.25}{x}}\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 0.25) 1.0 (sqrt (/ 0.25 x))))
double code(double x) {
	double tmp;
	if (x <= 0.25) {
		tmp = 1.0;
	} else {
		tmp = sqrt((0.25 / x));
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 0.25d0) then
        tmp = 1.0d0
    else
        tmp = sqrt((0.25d0 / x))
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 0.25) {
		tmp = 1.0;
	} else {
		tmp = Math.sqrt((0.25 / x));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 0.25:
		tmp = 1.0
	else:
		tmp = math.sqrt((0.25 / x))
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 0.25)
		tmp = 1.0;
	else
		tmp = sqrt(Float64(0.25 / x));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 0.25)
		tmp = 1.0;
	else
		tmp = sqrt((0.25 / x));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 0.25], 1.0, N[Sqrt[N[(0.25 / x), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.25:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{0.25}{x}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.25

    1. Initial program 100.0%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Taylor expanded in x around 0 95.6%

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

    if 0.25 < x

    1. Initial program 5.5%

      \[\sqrt{x + 1} - \sqrt{x} \]
    2. Step-by-step derivation
      1. flip--5.6%

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}}{\sqrt{x + 1} + \sqrt{x}}} \]
      2. div-inv5.6%

        \[\leadsto \color{blue}{\left(\sqrt{x + 1} \cdot \sqrt{x + 1} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
      3. add-sqr-sqrt6.3%

        \[\leadsto \left(\color{blue}{\left(x + 1\right)} - \sqrt{x} \cdot \sqrt{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. add-sqr-sqrt7.8%

        \[\leadsto \left(\left(x + 1\right) - \color{blue}{x}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate--l+7.8%

        \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
    3. Applied egg-rr7.8%

      \[\leadsto \color{blue}{\left(x + \left(1 - x\right)\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}}} \]
    4. Step-by-step derivation
      1. +-commutative7.8%

        \[\leadsto \color{blue}{\left(\left(1 - x\right) + x\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      2. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(1 - \left(x - x\right)\right)} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      3. +-inverses99.5%

        \[\leadsto \left(1 - \color{blue}{0}\right) \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      4. metadata-eval99.5%

        \[\leadsto \color{blue}{1} \cdot \frac{1}{\sqrt{x + 1} + \sqrt{x}} \]
      5. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot 1}{\sqrt{x + 1} + \sqrt{x}}} \]
      6. metadata-eval99.5%

        \[\leadsto \frac{\color{blue}{1}}{\sqrt{x + 1} + \sqrt{x}} \]
      7. +-commutative99.5%

        \[\leadsto \frac{1}{\sqrt{\color{blue}{1 + x}} + \sqrt{x}} \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{1 + x} + \sqrt{x}}} \]
    6. Step-by-step derivation
      1. flip3-+67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}}} \]
      2. clear-num67.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\sqrt{1 + x} \cdot \sqrt{1 + x} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}}} \]
      3. add-sqr-sqrt66.7%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(1 + x\right)} + \left(\sqrt{x} \cdot \sqrt{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      4. add-sqr-sqrt66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(1 + x\right) + \left(\color{blue}{x} - \sqrt{1 + x} \cdot \sqrt{x}\right)}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      5. associate-+r-66.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\color{blue}{\left(\left(1 + x\right) + x\right) - \sqrt{1 + x} \cdot \sqrt{x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      6. sqrt-unprod52.3%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \color{blue}{\sqrt{\left(1 + x\right) \cdot x}}}{{\left(\sqrt{1 + x}\right)}^{3} + {\left(\sqrt{x}\right)}^{3}}}} \]
      7. sqrt-pow252.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{\color{blue}{{\left(1 + x\right)}^{\left(\frac{3}{2}\right)}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      8. metadata-eval52.5%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{\color{blue}{1.5}} + {\left(\sqrt{x}\right)}^{3}}}} \]
      9. sqrt-pow252.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + \color{blue}{{x}^{\left(\frac{3}{2}\right)}}}}} \]
      10. metadata-eval52.6%

        \[\leadsto \frac{1}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{\color{blue}{1.5}}}}} \]
    7. Applied egg-rr52.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(1 + x\right) + x\right) - \sqrt{\left(1 + x\right) \cdot x}}{{\left(1 + x\right)}^{1.5} + {x}^{1.5}}}}} \]
    8. Taylor expanded in x around inf 98.7%

      \[\leadsto \frac{1}{\color{blue}{2 \cdot \sqrt{x}}} \]
    9. Step-by-step derivation
      1. *-commutative98.7%

        \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    10. Simplified98.7%

      \[\leadsto \frac{1}{\color{blue}{\sqrt{x} \cdot 2}} \]
    11. Step-by-step derivation
      1. add-sqr-sqrt98.3%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\sqrt{x} \cdot 2}} \cdot \sqrt{\frac{1}{\sqrt{x} \cdot 2}}} \]
      2. sqrt-unprod98.7%

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\sqrt{x} \cdot 2} \cdot \frac{1}{\sqrt{x} \cdot 2}}} \]
      3. frac-times97.9%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot 1}{\left(\sqrt{x} \cdot 2\right) \cdot \left(\sqrt{x} \cdot 2\right)}}} \]
      4. metadata-eval97.9%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\left(\sqrt{x} \cdot 2\right) \cdot \left(\sqrt{x} \cdot 2\right)}} \]
      5. swap-sqr97.9%

        \[\leadsto \sqrt{\frac{1}{\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right) \cdot \left(2 \cdot 2\right)}}} \]
      6. add-sqr-sqrt98.3%

        \[\leadsto \sqrt{\frac{1}{\color{blue}{x} \cdot \left(2 \cdot 2\right)}} \]
      7. metadata-eval98.3%

        \[\leadsto \sqrt{\frac{1}{x \cdot \color{blue}{4}}} \]
    12. Applied egg-rr98.3%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{x \cdot 4}}} \]
    13. Step-by-step derivation
      1. *-commutative98.3%

        \[\leadsto \sqrt{\frac{1}{\color{blue}{4 \cdot x}}} \]
      2. associate-/r*98.9%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{1}{4}}{x}}} \]
      3. metadata-eval98.9%

        \[\leadsto \sqrt{\frac{\color{blue}{0.25}}{x}} \]
    14. Simplified98.9%

      \[\leadsto \color{blue}{\sqrt{\frac{0.25}{x}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.25:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{0.25}{x}}\\ \end{array} \]

Alternative 8: 51.8% accurate, 205.0× speedup?

\[\begin{array}{l} \\ 1 \end{array} \]
(FPCore (x) :precision binary64 1.0)
double code(double x) {
	return 1.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0
end function
public static double code(double x) {
	return 1.0;
}
def code(x):
	return 1.0
function code(x)
	return 1.0
end
function tmp = code(x)
	tmp = 1.0;
end
code[x_] := 1.0
\begin{array}{l}

\\
1
\end{array}
Derivation
  1. Initial program 46.8%

    \[\sqrt{x + 1} - \sqrt{x} \]
  2. Taylor expanded in x around 0 45.7%

    \[\leadsto \color{blue}{1} \]
  3. Final simplification45.7%

    \[\leadsto 1 \]

Developer target: 99.7% accurate, 1.0× speedup?

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

\\
\frac{1}{\sqrt{x + 1} + \sqrt{x}}
\end{array}

Reproduce

?
herbie shell --seed 2023315 
(FPCore (x)
  :name "Main:bigenough3 from C"
  :precision binary64

  :herbie-target
  (/ 1.0 (+ (sqrt (+ x 1.0)) (sqrt x)))

  (- (sqrt (+ x 1.0)) (sqrt x)))