NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.6% → 99.7%
Time: 8.3s
Alternatives: 8
Speedup: 1.1×

Specification

?
\[\begin{array}{l} \\ \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \end{array} \]
(FPCore (a b)
 :precision binary64
 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
	return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
	return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b):
	return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b)
	return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b)))
end
function tmp = code(a, b)
	tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 8 alternatives:

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

Initial Program: 78.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \end{array} \]
(FPCore (a b)
 :precision binary64
 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
	return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
	return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b):
	return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b)
	return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b)))
end
function tmp = code(a, b)
	tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}

Alternative 1: 99.7% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{\frac{\frac{0.5 \cdot \pi}{a}}{b}}{a + b} \end{array} \]
(FPCore (a b) :precision binary64 (/ (/ (/ (* 0.5 PI) a) b) (+ a b)))
double code(double a, double b) {
	return (((0.5 * ((double) M_PI)) / a) / b) / (a + b);
}
public static double code(double a, double b) {
	return (((0.5 * Math.PI) / a) / b) / (a + b);
}
def code(a, b):
	return (((0.5 * math.pi) / a) / b) / (a + b)
function code(a, b)
	return Float64(Float64(Float64(Float64(0.5 * pi) / a) / b) / Float64(a + b))
end
function tmp = code(a, b)
	tmp = (((0.5 * pi) / a) / b) / (a + b);
end
code[a_, b_] := N[(N[(N[(N[(0.5 * Pi), $MachinePrecision] / a), $MachinePrecision] / b), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\frac{0.5 \cdot \pi}{a}}{b}}{a + b}
\end{array}
Derivation
  1. Initial program 82.3%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. div-inv82.3%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. clear-num82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. frac-sub82.3%

      \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
    4. frac-times77.1%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
    5. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    6. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    7. div-inv77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
    8. metadata-eval77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
  3. Applied egg-rr77.1%

    \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
  4. Step-by-step derivation
    1. *-rgt-identity77.1%

      \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
    2. *-commutative77.1%

      \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
    3. associate-*r/77.0%

      \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
    4. associate-/l*76.7%

      \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
    5. *-commutative76.7%

      \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    6. associate-*l*76.7%

      \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    7. *-commutative76.7%

      \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  5. Simplified76.7%

    \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  6. Step-by-step derivation
    1. *-un-lft-identity76.7%

      \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    2. times-frac82.3%

      \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
    3. *-commutative82.3%

      \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
  7. Applied egg-rr82.3%

    \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
  8. Step-by-step derivation
    1. *-lft-identity82.3%

      \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
    2. associate-*l/82.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
    3. difference-of-squares89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    4. +-commutative89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
    5. times-frac99.6%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
    6. *-commutative99.6%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
    7. times-frac89.3%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
  9. Simplified89.3%

    \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
  10. Step-by-step derivation
    1. frac-times82.5%

      \[\leadsto \color{blue}{\frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\left(a + b\right) \cdot \left(b - a\right)}} \]
    2. *-commutative82.5%

      \[\leadsto \frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\color{blue}{\left(b - a\right) \cdot \left(a + b\right)}} \]
  11. Applied egg-rr82.5%

    \[\leadsto \color{blue}{\frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\left(b - a\right) \cdot \left(a + b\right)}} \]
  12. Step-by-step derivation
    1. *-commutative82.5%

      \[\leadsto \frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\color{blue}{\left(a + b\right) \cdot \left(b - a\right)}} \]
    2. times-frac89.3%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
    3. associate-*l/88.5%

      \[\leadsto \frac{\pi}{a + b} \cdot \color{blue}{\left(\frac{\frac{0.5}{a}}{b - a} \cdot \frac{b - a}{b}\right)} \]
    4. associate-/r/89.3%

      \[\leadsto \frac{\pi}{a + b} \cdot \color{blue}{\frac{\frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}} \]
    5. associate-*l/89.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b}} \]
    6. associate-*r/89.3%

      \[\leadsto \frac{\color{blue}{\frac{\pi \cdot \frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}}}{a + b} \]
    7. *-commutative89.3%

      \[\leadsto \frac{\frac{\color{blue}{\frac{0.5}{a} \cdot \pi}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b} \]
    8. associate-*l/89.4%

      \[\leadsto \frac{\frac{\color{blue}{\frac{0.5 \cdot \pi}{a}}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b} \]
    9. associate-/r/99.7%

      \[\leadsto \frac{\frac{\frac{0.5 \cdot \pi}{a}}{\color{blue}{\frac{b - a}{b - a} \cdot b}}}{a + b} \]
    10. *-inverses99.7%

      \[\leadsto \frac{\frac{\frac{0.5 \cdot \pi}{a}}{\color{blue}{1} \cdot b}}{a + b} \]
  13. Simplified99.7%

    \[\leadsto \color{blue}{\frac{\frac{\frac{0.5 \cdot \pi}{a}}{1 \cdot b}}{a + b}} \]
  14. Final simplification99.7%

    \[\leadsto \frac{\frac{\frac{0.5 \cdot \pi}{a}}{b}}{a + b} \]

Alternative 2: 66.7% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -3.3 \cdot 10^{-119}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -3.3e-119)
   (* (/ 0.5 a) (/ PI (* a b)))
   (* (/ 0.5 a) (/ PI (* b b)))))
double code(double a, double b) {
	double tmp;
	if (a <= -3.3e-119) {
		tmp = (0.5 / a) * (((double) M_PI) / (a * b));
	} else {
		tmp = (0.5 / a) * (((double) M_PI) / (b * b));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -3.3e-119) {
		tmp = (0.5 / a) * (Math.PI / (a * b));
	} else {
		tmp = (0.5 / a) * (Math.PI / (b * b));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -3.3e-119:
		tmp = (0.5 / a) * (math.pi / (a * b))
	else:
		tmp = (0.5 / a) * (math.pi / (b * b))
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -3.3e-119)
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)));
	else
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(b * b)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -3.3e-119)
		tmp = (0.5 / a) * (pi / (a * b));
	else
		tmp = (0.5 / a) * (pi / (b * b));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -3.3e-119], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -3.3 \cdot 10^{-119}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\

\mathbf{else}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -3.30000000000000008e-119

    1. Initial program 84.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Taylor expanded in b around 0 74.7%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    3. Step-by-step derivation
      1. associate-*r/74.7%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. unpow274.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot a\right)} \cdot b} \]
    4. Simplified74.7%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot a\right) \cdot b}} \]
    5. Step-by-step derivation
      1. associate-*l*80.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
      2. times-frac80.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
    6. Applied egg-rr80.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]

    if -3.30000000000000008e-119 < a

    1. Initial program 81.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Taylor expanded in b around inf 61.2%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    3. Step-by-step derivation
      1. associate-*r/61.2%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. unpow261.2%

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
    4. Simplified61.2%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot b\right)}} \]
    5. Step-by-step derivation
      1. times-frac60.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}} \]
    6. Applied egg-rr60.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification68.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -3.3 \cdot 10^{-119}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}\\ \end{array} \]

Alternative 3: 72.5% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2.5 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -2.5e-116)
   (* (/ 0.5 a) (/ PI (* a b)))
   (* (/ 0.5 (* a b)) (/ PI b))))
double code(double a, double b) {
	double tmp;
	if (a <= -2.5e-116) {
		tmp = (0.5 / a) * (((double) M_PI) / (a * b));
	} else {
		tmp = (0.5 / (a * b)) * (((double) M_PI) / b);
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -2.5e-116) {
		tmp = (0.5 / a) * (Math.PI / (a * b));
	} else {
		tmp = (0.5 / (a * b)) * (Math.PI / b);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -2.5e-116:
		tmp = (0.5 / a) * (math.pi / (a * b))
	else:
		tmp = (0.5 / (a * b)) * (math.pi / b)
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -2.5e-116)
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)));
	else
		tmp = Float64(Float64(0.5 / Float64(a * b)) * Float64(pi / b));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -2.5e-116)
		tmp = (0.5 / a) * (pi / (a * b));
	else
		tmp = (0.5 / (a * b)) * (pi / b);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -2.5e-116], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 / N[(a * b), $MachinePrecision]), $MachinePrecision] * N[(Pi / b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2.5 \cdot 10^{-116}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\

\mathbf{else}:\\
\;\;\;\;\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2.5000000000000001e-116

    1. Initial program 84.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Taylor expanded in b around 0 74.7%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    3. Step-by-step derivation
      1. associate-*r/74.7%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. unpow274.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot a\right)} \cdot b} \]
    4. Simplified74.7%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot a\right) \cdot b}} \]
    5. Step-by-step derivation
      1. associate-*l*80.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
      2. times-frac80.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
    6. Applied egg-rr80.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]

    if -2.5000000000000001e-116 < a

    1. Initial program 81.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. div-inv81.3%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. clear-num81.3%

        \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. frac-sub81.3%

        \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
      4. frac-times75.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
      5. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      6. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      7. div-inv75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
      8. metadata-eval75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
    3. Applied egg-rr75.9%

      \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
    4. Step-by-step derivation
      1. *-rgt-identity75.9%

        \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
      2. *-commutative75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
      3. associate-*r/75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
      4. associate-/l*76.0%

        \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
      5. *-commutative76.0%

        \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      6. associate-*l*76.0%

        \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      7. *-commutative76.0%

        \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    5. Simplified76.0%

      \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    6. Step-by-step derivation
      1. *-un-lft-identity76.0%

        \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
      2. times-frac81.3%

        \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
      3. *-commutative81.3%

        \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
    7. Applied egg-rr81.3%

      \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
    8. Step-by-step derivation
      1. *-lft-identity81.3%

        \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
      2. associate-*l/81.3%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
      3. difference-of-squares87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      4. +-commutative87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
      5. times-frac99.5%

        \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
      6. *-commutative99.5%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
      7. times-frac92.4%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
    9. Simplified92.4%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
    10. Taylor expanded in a around 0 61.2%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/61.2%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. unpow261.2%

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
      3. associate-*r*70.4%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot b\right) \cdot b}} \]
      4. times-frac70.1%

        \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
    12. Simplified70.1%

      \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2.5 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}\\ \end{array} \]

Alternative 4: 72.4% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2.55 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{\left(a \cdot b\right) \cdot \frac{b}{\pi}}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -2.55e-116)
   (* (/ 0.5 a) (/ PI (* a b)))
   (/ 0.5 (* (* a b) (/ b PI)))))
double code(double a, double b) {
	double tmp;
	if (a <= -2.55e-116) {
		tmp = (0.5 / a) * (((double) M_PI) / (a * b));
	} else {
		tmp = 0.5 / ((a * b) * (b / ((double) M_PI)));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -2.55e-116) {
		tmp = (0.5 / a) * (Math.PI / (a * b));
	} else {
		tmp = 0.5 / ((a * b) * (b / Math.PI));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -2.55e-116:
		tmp = (0.5 / a) * (math.pi / (a * b))
	else:
		tmp = 0.5 / ((a * b) * (b / math.pi))
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -2.55e-116)
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)));
	else
		tmp = Float64(0.5 / Float64(Float64(a * b) * Float64(b / pi)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -2.55e-116)
		tmp = (0.5 / a) * (pi / (a * b));
	else
		tmp = 0.5 / ((a * b) * (b / pi));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -2.55e-116], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 / N[(N[(a * b), $MachinePrecision] * N[(b / Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2.55 \cdot 10^{-116}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\

\mathbf{else}:\\
\;\;\;\;\frac{0.5}{\left(a \cdot b\right) \cdot \frac{b}{\pi}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2.5500000000000001e-116

    1. Initial program 84.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Taylor expanded in b around 0 74.7%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    3. Step-by-step derivation
      1. associate-*r/74.7%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. unpow274.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot a\right)} \cdot b} \]
    4. Simplified74.7%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot a\right) \cdot b}} \]
    5. Step-by-step derivation
      1. associate-*l*80.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
      2. times-frac80.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
    6. Applied egg-rr80.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]

    if -2.5500000000000001e-116 < a

    1. Initial program 81.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. div-inv81.3%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. clear-num81.3%

        \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. frac-sub81.3%

        \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
      4. frac-times75.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
      5. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      6. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      7. div-inv75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
      8. metadata-eval75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
    3. Applied egg-rr75.9%

      \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
    4. Step-by-step derivation
      1. *-rgt-identity75.9%

        \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
      2. *-commutative75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
      3. associate-*r/75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
      4. associate-/l*76.0%

        \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
      5. *-commutative76.0%

        \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      6. associate-*l*76.0%

        \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      7. *-commutative76.0%

        \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    5. Simplified76.0%

      \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    6. Step-by-step derivation
      1. *-un-lft-identity76.0%

        \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
      2. times-frac81.3%

        \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
      3. *-commutative81.3%

        \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
    7. Applied egg-rr81.3%

      \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
    8. Step-by-step derivation
      1. *-lft-identity81.3%

        \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
      2. associate-*l/81.3%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
      3. difference-of-squares87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      4. +-commutative87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
      5. times-frac99.5%

        \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
      6. *-commutative99.5%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
      7. times-frac92.4%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
    9. Simplified92.4%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
    10. Taylor expanded in a around 0 61.2%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/61.2%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. unpow261.2%

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
      3. associate-*r*70.4%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot b\right) \cdot b}} \]
      4. times-frac70.1%

        \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
    12. Simplified70.1%

      \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
    13. Step-by-step derivation
      1. *-commutative70.1%

        \[\leadsto \color{blue}{\frac{\pi}{b} \cdot \frac{0.5}{a \cdot b}} \]
      2. clear-num70.1%

        \[\leadsto \color{blue}{\frac{1}{\frac{b}{\pi}}} \cdot \frac{0.5}{a \cdot b} \]
      3. frac-times70.4%

        \[\leadsto \color{blue}{\frac{1 \cdot 0.5}{\frac{b}{\pi} \cdot \left(a \cdot b\right)}} \]
      4. metadata-eval70.4%

        \[\leadsto \frac{\color{blue}{0.5}}{\frac{b}{\pi} \cdot \left(a \cdot b\right)} \]
    14. Applied egg-rr70.4%

      \[\leadsto \color{blue}{\frac{0.5}{\frac{b}{\pi} \cdot \left(a \cdot b\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2.55 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{\left(a \cdot b\right) \cdot \frac{b}{\pi}}\\ \end{array} \]

Alternative 5: 72.4% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2.2 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -2.2e-116)
   (* (/ 0.5 a) (/ PI (* a b)))
   (/ (* 0.5 PI) (* b (* a b)))))
double code(double a, double b) {
	double tmp;
	if (a <= -2.2e-116) {
		tmp = (0.5 / a) * (((double) M_PI) / (a * b));
	} else {
		tmp = (0.5 * ((double) M_PI)) / (b * (a * b));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -2.2e-116) {
		tmp = (0.5 / a) * (Math.PI / (a * b));
	} else {
		tmp = (0.5 * Math.PI) / (b * (a * b));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -2.2e-116:
		tmp = (0.5 / a) * (math.pi / (a * b))
	else:
		tmp = (0.5 * math.pi) / (b * (a * b))
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -2.2e-116)
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)));
	else
		tmp = Float64(Float64(0.5 * pi) / Float64(b * Float64(a * b)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -2.2e-116)
		tmp = (0.5 / a) * (pi / (a * b));
	else
		tmp = (0.5 * pi) / (b * (a * b));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -2.2e-116], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * Pi), $MachinePrecision] / N[(b * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2.2 \cdot 10^{-116}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\

\mathbf{else}:\\
\;\;\;\;\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2.2000000000000001e-116

    1. Initial program 84.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Taylor expanded in b around 0 74.7%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    3. Step-by-step derivation
      1. associate-*r/74.7%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. unpow274.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot a\right)} \cdot b} \]
    4. Simplified74.7%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot a\right) \cdot b}} \]
    5. Step-by-step derivation
      1. associate-*l*80.7%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
      2. times-frac80.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
    6. Applied egg-rr80.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]

    if -2.2000000000000001e-116 < a

    1. Initial program 81.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. div-inv81.3%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. clear-num81.3%

        \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. frac-sub81.3%

        \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
      4. frac-times75.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
      5. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      6. *-un-lft-identity75.9%

        \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
      7. div-inv75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
      8. metadata-eval75.9%

        \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
    3. Applied egg-rr75.9%

      \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
    4. Step-by-step derivation
      1. *-rgt-identity75.9%

        \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
      2. *-commutative75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
      3. associate-*r/75.9%

        \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
      4. associate-/l*76.0%

        \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
      5. *-commutative76.0%

        \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      6. associate-*l*76.0%

        \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
      7. *-commutative76.0%

        \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    5. Simplified76.0%

      \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    6. Step-by-step derivation
      1. *-un-lft-identity76.0%

        \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
      2. times-frac81.3%

        \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
      3. *-commutative81.3%

        \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
    7. Applied egg-rr81.3%

      \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
    8. Step-by-step derivation
      1. *-lft-identity81.3%

        \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
      2. associate-*l/81.3%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
      3. difference-of-squares87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      4. +-commutative87.5%

        \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
      5. times-frac99.5%

        \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
      6. *-commutative99.5%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
      7. times-frac92.4%

        \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
    9. Simplified92.4%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
    10. Taylor expanded in a around 0 61.2%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/61.2%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. unpow261.2%

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
      3. associate-*r*70.4%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot b\right) \cdot b}} \]
      4. times-frac70.1%

        \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
    12. Simplified70.1%

      \[\leadsto \color{blue}{\frac{0.5}{a \cdot b} \cdot \frac{\pi}{b}} \]
    13. Step-by-step derivation
      1. frac-times70.4%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot b}} \]
    14. Applied egg-rr70.4%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2.2 \cdot 10^{-116}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}\\ \end{array} \]

Alternative 6: 99.6% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{\pi}{a + b} \cdot \frac{0.5}{a \cdot b} \end{array} \]
(FPCore (a b) :precision binary64 (* (/ PI (+ a b)) (/ 0.5 (* a b))))
double code(double a, double b) {
	return (((double) M_PI) / (a + b)) * (0.5 / (a * b));
}
public static double code(double a, double b) {
	return (Math.PI / (a + b)) * (0.5 / (a * b));
}
def code(a, b):
	return (math.pi / (a + b)) * (0.5 / (a * b))
function code(a, b)
	return Float64(Float64(pi / Float64(a + b)) * Float64(0.5 / Float64(a * b)))
end
function tmp = code(a, b)
	tmp = (pi / (a + b)) * (0.5 / (a * b));
end
code[a_, b_] := N[(N[(Pi / N[(a + b), $MachinePrecision]), $MachinePrecision] * N[(0.5 / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\pi}{a + b} \cdot \frac{0.5}{a \cdot b}
\end{array}
Derivation
  1. Initial program 82.3%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. div-inv82.3%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. clear-num82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. frac-sub82.3%

      \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
    4. frac-times77.1%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
    5. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    6. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    7. div-inv77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
    8. metadata-eval77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
  3. Applied egg-rr77.1%

    \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
  4. Step-by-step derivation
    1. *-rgt-identity77.1%

      \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
    2. *-commutative77.1%

      \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
    3. associate-*r/77.0%

      \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
    4. associate-/l*76.7%

      \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
    5. *-commutative76.7%

      \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    6. associate-*l*76.7%

      \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    7. *-commutative76.7%

      \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  5. Simplified76.7%

    \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  6. Step-by-step derivation
    1. *-un-lft-identity76.7%

      \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    2. times-frac82.3%

      \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
    3. *-commutative82.3%

      \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
  7. Applied egg-rr82.3%

    \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
  8. Step-by-step derivation
    1. *-lft-identity82.3%

      \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
    2. associate-*l/82.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
    3. difference-of-squares89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    4. +-commutative89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
    5. times-frac99.6%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
    6. *-commutative99.6%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
    7. times-frac89.3%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
  9. Simplified89.3%

    \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
  10. Taylor expanded in a around 0 99.6%

    \[\leadsto \frac{\pi}{a + b} \cdot \color{blue}{\frac{0.5}{a \cdot b}} \]
  11. Final simplification99.6%

    \[\leadsto \frac{\pi}{a + b} \cdot \frac{0.5}{a \cdot b} \]

Alternative 7: 99.6% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{\frac{\frac{0.5}{\frac{a}{\pi}}}{b}}{a + b} \end{array} \]
(FPCore (a b) :precision binary64 (/ (/ (/ 0.5 (/ a PI)) b) (+ a b)))
double code(double a, double b) {
	return ((0.5 / (a / ((double) M_PI))) / b) / (a + b);
}
public static double code(double a, double b) {
	return ((0.5 / (a / Math.PI)) / b) / (a + b);
}
def code(a, b):
	return ((0.5 / (a / math.pi)) / b) / (a + b)
function code(a, b)
	return Float64(Float64(Float64(0.5 / Float64(a / pi)) / b) / Float64(a + b))
end
function tmp = code(a, b)
	tmp = ((0.5 / (a / pi)) / b) / (a + b);
end
code[a_, b_] := N[(N[(N[(0.5 / N[(a / Pi), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\frac{0.5}{\frac{a}{\pi}}}{b}}{a + b}
\end{array}
Derivation
  1. Initial program 82.3%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. div-inv82.3%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. clear-num82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. frac-sub82.3%

      \[\leadsto \frac{1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}} \cdot \color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \]
    4. frac-times77.1%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(1 \cdot b - a \cdot 1\right)}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)}} \]
    5. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{1 \cdot b - a \cdot 1}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    6. *-un-lft-identity77.1%

      \[\leadsto \frac{\color{blue}{b} - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}} \cdot \left(a \cdot b\right)} \]
    7. div-inv77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\color{blue}{\pi \cdot \frac{1}{2}}} \cdot \left(a \cdot b\right)} \]
    8. metadata-eval77.1%

      \[\leadsto \frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot \color{blue}{0.5}} \cdot \left(a \cdot b\right)} \]
  3. Applied egg-rr77.1%

    \[\leadsto \color{blue}{\frac{b - a \cdot 1}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)}} \]
  4. Step-by-step derivation
    1. *-rgt-identity77.1%

      \[\leadsto \frac{b - \color{blue}{a}}{\frac{b \cdot b - a \cdot a}{\pi \cdot 0.5} \cdot \left(a \cdot b\right)} \]
    2. *-commutative77.1%

      \[\leadsto \frac{b - a}{\color{blue}{\left(a \cdot b\right) \cdot \frac{b \cdot b - a \cdot a}{\pi \cdot 0.5}}} \]
    3. associate-*r/77.0%

      \[\leadsto \frac{b - a}{\color{blue}{\frac{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}{\pi \cdot 0.5}}} \]
    4. associate-/l*76.7%

      \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)}} \]
    5. *-commutative76.7%

      \[\leadsto \frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(b - a\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    6. associate-*l*76.7%

      \[\leadsto \frac{\color{blue}{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}}{\left(a \cdot b\right) \cdot \left(b \cdot b - a \cdot a\right)} \]
    7. *-commutative76.7%

      \[\leadsto \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\color{blue}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  5. Simplified76.7%

    \[\leadsto \color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
  6. Step-by-step derivation
    1. *-un-lft-identity76.7%

      \[\leadsto \color{blue}{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(b - a\right)\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(a \cdot b\right)}} \]
    2. times-frac82.3%

      \[\leadsto 1 \cdot \color{blue}{\left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{0.5 \cdot \left(b - a\right)}{a \cdot b}\right)} \]
    3. *-commutative82.3%

      \[\leadsto 1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\color{blue}{\left(b - a\right) \cdot 0.5}}{a \cdot b}\right) \]
  7. Applied egg-rr82.3%

    \[\leadsto \color{blue}{1 \cdot \left(\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}\right)} \]
  8. Step-by-step derivation
    1. *-lft-identity82.3%

      \[\leadsto \color{blue}{\frac{\pi}{b \cdot b - a \cdot a} \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}} \]
    2. associate-*l/82.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b \cdot b - a \cdot a}} \]
    3. difference-of-squares89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    4. +-commutative89.7%

      \[\leadsto \frac{\pi \cdot \frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{\color{blue}{\left(a + b\right)} \cdot \left(b - a\right)} \]
    5. times-frac99.6%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{\left(b - a\right) \cdot 0.5}{a \cdot b}}{b - a}} \]
    6. *-commutative99.6%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\frac{\color{blue}{0.5 \cdot \left(b - a\right)}}{a \cdot b}}{b - a} \]
    7. times-frac89.3%

      \[\leadsto \frac{\pi}{a + b} \cdot \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{b - a}{b}}}{b - a} \]
  9. Simplified89.3%

    \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
  10. Step-by-step derivation
    1. frac-times82.5%

      \[\leadsto \color{blue}{\frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\left(a + b\right) \cdot \left(b - a\right)}} \]
    2. *-commutative82.5%

      \[\leadsto \frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\color{blue}{\left(b - a\right) \cdot \left(a + b\right)}} \]
  11. Applied egg-rr82.5%

    \[\leadsto \color{blue}{\frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\left(b - a\right) \cdot \left(a + b\right)}} \]
  12. Step-by-step derivation
    1. *-commutative82.5%

      \[\leadsto \frac{\pi \cdot \left(\frac{0.5}{a} \cdot \frac{b - a}{b}\right)}{\color{blue}{\left(a + b\right) \cdot \left(b - a\right)}} \]
    2. times-frac89.3%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{\frac{0.5}{a} \cdot \frac{b - a}{b}}{b - a}} \]
    3. associate-*l/88.5%

      \[\leadsto \frac{\pi}{a + b} \cdot \color{blue}{\left(\frac{\frac{0.5}{a}}{b - a} \cdot \frac{b - a}{b}\right)} \]
    4. associate-/r/89.3%

      \[\leadsto \frac{\pi}{a + b} \cdot \color{blue}{\frac{\frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}} \]
    5. associate-*l/89.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{\frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b}} \]
    6. associate-*r/89.3%

      \[\leadsto \frac{\color{blue}{\frac{\pi \cdot \frac{0.5}{a}}{\frac{b - a}{\frac{b - a}{b}}}}}{a + b} \]
    7. *-commutative89.3%

      \[\leadsto \frac{\frac{\color{blue}{\frac{0.5}{a} \cdot \pi}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b} \]
    8. associate-*l/89.4%

      \[\leadsto \frac{\frac{\color{blue}{\frac{0.5 \cdot \pi}{a}}}{\frac{b - a}{\frac{b - a}{b}}}}{a + b} \]
    9. associate-/r/99.7%

      \[\leadsto \frac{\frac{\frac{0.5 \cdot \pi}{a}}{\color{blue}{\frac{b - a}{b - a} \cdot b}}}{a + b} \]
    10. *-inverses99.7%

      \[\leadsto \frac{\frac{\frac{0.5 \cdot \pi}{a}}{\color{blue}{1} \cdot b}}{a + b} \]
  13. Simplified99.7%

    \[\leadsto \color{blue}{\frac{\frac{\frac{0.5 \cdot \pi}{a}}{1 \cdot b}}{a + b}} \]
  14. Step-by-step derivation
    1. clear-num99.7%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{\frac{a}{0.5 \cdot \pi}}}}{1 \cdot b}}{a + b} \]
    2. inv-pow99.7%

      \[\leadsto \frac{\frac{\color{blue}{{\left(\frac{a}{0.5 \cdot \pi}\right)}^{-1}}}{1 \cdot b}}{a + b} \]
    3. *-un-lft-identity99.7%

      \[\leadsto \frac{\frac{{\left(\frac{\color{blue}{1 \cdot a}}{0.5 \cdot \pi}\right)}^{-1}}{1 \cdot b}}{a + b} \]
    4. times-frac99.7%

      \[\leadsto \frac{\frac{{\color{blue}{\left(\frac{1}{0.5} \cdot \frac{a}{\pi}\right)}}^{-1}}{1 \cdot b}}{a + b} \]
    5. metadata-eval99.7%

      \[\leadsto \frac{\frac{{\left(\color{blue}{2} \cdot \frac{a}{\pi}\right)}^{-1}}{1 \cdot b}}{a + b} \]
  15. Applied egg-rr99.7%

    \[\leadsto \frac{\frac{\color{blue}{{\left(2 \cdot \frac{a}{\pi}\right)}^{-1}}}{1 \cdot b}}{a + b} \]
  16. Step-by-step derivation
    1. unpow-199.7%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{2 \cdot \frac{a}{\pi}}}}{1 \cdot b}}{a + b} \]
    2. associate-/r*99.7%

      \[\leadsto \frac{\frac{\color{blue}{\frac{\frac{1}{2}}{\frac{a}{\pi}}}}{1 \cdot b}}{a + b} \]
    3. metadata-eval99.7%

      \[\leadsto \frac{\frac{\frac{\color{blue}{0.5}}{\frac{a}{\pi}}}{1 \cdot b}}{a + b} \]
  17. Simplified99.7%

    \[\leadsto \frac{\frac{\color{blue}{\frac{0.5}{\frac{a}{\pi}}}}{1 \cdot b}}{a + b} \]
  18. Final simplification99.7%

    \[\leadsto \frac{\frac{\frac{0.5}{\frac{a}{\pi}}}{b}}{a + b} \]

Alternative 8: 62.3% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{0.5}{a} \cdot \frac{\pi}{a \cdot b} \end{array} \]
(FPCore (a b) :precision binary64 (* (/ 0.5 a) (/ PI (* a b))))
double code(double a, double b) {
	return (0.5 / a) * (((double) M_PI) / (a * b));
}
public static double code(double a, double b) {
	return (0.5 / a) * (Math.PI / (a * b));
}
def code(a, b):
	return (0.5 / a) * (math.pi / (a * b))
function code(a, b)
	return Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)))
end
function tmp = code(a, b)
	tmp = (0.5 / a) * (pi / (a * b));
end
code[a_, b_] := N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}
\end{array}
Derivation
  1. Initial program 82.3%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Taylor expanded in b around 0 58.8%

    \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
  3. Step-by-step derivation
    1. associate-*r/58.8%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
    2. unpow258.8%

      \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{\left(a \cdot a\right)} \cdot b} \]
  4. Simplified58.8%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot a\right) \cdot b}} \]
  5. Step-by-step derivation
    1. associate-*l*62.8%

      \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
    2. times-frac62.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
  6. Applied egg-rr62.8%

    \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}} \]
  7. Final simplification62.8%

    \[\leadsto \frac{0.5}{a} \cdot \frac{\pi}{a \cdot b} \]

Reproduce

?
herbie shell --seed 2023272 
(FPCore (a b)
  :name "NMSE Section 6.1 mentioned, B"
  :precision binary64
  (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))