NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.7% → 99.7%
Time: 10.3s
Alternatives: 7
Speedup: 1.9×

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 7 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: 78.7% 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, 1.9× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5 \cdot \frac{\frac{\pi}{a}}{b}}{a + b} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (* 0.5 (/ (/ PI a) b)) (+ a b)))
assert(a < b);
double code(double a, double b) {
	return (0.5 * ((((double) M_PI) / a) / b)) / (a + b);
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 * ((Math.PI / a) / b)) / (a + b);
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 * ((math.pi / a) / b)) / (a + b)
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 * Float64(Float64(pi / a) / b)) / Float64(a + b))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 * ((pi / a) / b)) / (a + b);
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 * N[(N[(Pi / a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5 \cdot \frac{\frac{\pi}{a}}{b}}{a + b}
\end{array}
Derivation
  1. Initial program 80.9%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*80.9%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/80.9%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity80.9%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified80.9%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity80.9%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares88.3%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    3. times-frac99.5%

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
  6. Applied egg-rr61.5%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/61.6%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}}{b + a}} \]
    2. *-lft-identity61.6%

      \[\leadsto \frac{\color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}}}{b + a} \]
    3. associate-*r*61.6%

      \[\leadsto \frac{\frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(\frac{1}{a} + \frac{1}{b}\right)}}{b - a}}{b + a} \]
    4. distribute-rgt-out61.6%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{a} \cdot \left(\pi \cdot 0.5\right) + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}}{b - a}}{b + a} \]
    5. associate-*l/61.6%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{a}} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    6. *-lft-identity61.6%

      \[\leadsto \frac{\frac{\frac{\color{blue}{\pi \cdot 0.5}}{a} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    7. *-commutative61.6%

      \[\leadsto \frac{\frac{\frac{\color{blue}{0.5 \cdot \pi}}{a} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    8. associate-*r/61.6%

      \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \frac{\pi}{a}} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    9. associate-*l/61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{b}}}{b - a}}{b + a} \]
    10. *-lft-identity61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \frac{\color{blue}{\pi \cdot 0.5}}{b}}{b - a}}{b + a} \]
    11. *-commutative61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \frac{\color{blue}{0.5 \cdot \pi}}{b}}{b - a}}{b + a} \]
    12. associate-*r/61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \color{blue}{0.5 \cdot \frac{\pi}{b}}}{b - a}}{b + a} \]
    13. fma-define61.6%

      \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(0.5, \frac{\pi}{a}, 0.5 \cdot \frac{\pi}{b}\right)}}{b - a}}{b + a} \]
    14. associate-*r/61.6%

      \[\leadsto \frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \color{blue}{\frac{0.5 \cdot \pi}{b}}\right)}{b - a}}{b + a} \]
    15. +-commutative61.6%

      \[\leadsto \frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \frac{0.5 \cdot \pi}{b}\right)}{b - a}}{\color{blue}{a + b}} \]
  8. Simplified61.6%

    \[\leadsto \color{blue}{\frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \frac{0.5 \cdot \pi}{b}\right)}{b - a}}{a + b}} \]
  9. Taylor expanded in a around 0 99.6%

    \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\pi}{a \cdot b}}}{a + b} \]
  10. Step-by-step derivation
    1. associate-*r/99.6%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  11. Applied egg-rr99.6%

    \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  12. Step-by-step derivation
    1. associate-/r*99.6%

      \[\leadsto \frac{\color{blue}{\frac{\frac{0.5 \cdot \pi}{a}}{b}}}{a + b} \]
    2. associate-*r/99.6%

      \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \frac{\pi}{a}}}{b}}{a + b} \]
    3. associate-*r/99.6%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\frac{\pi}{a}}{b}}}{a + b} \]
  13. Simplified99.6%

    \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\frac{\pi}{a}}{b}}}{a + b} \]
  14. Add Preprocessing

Alternative 2: 99.3% accurate, 1.3× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;b \leq 2.85 \cdot 10^{+147}:\\ \;\;\;\;\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot \left(a + b\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{b}}{a \cdot b}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= b 2.85e+147)
   (/ (* 0.5 PI) (* a (* b (+ a b))))
   (/ (* 0.5 (/ PI b)) (* a b))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (b <= 2.85e+147) {
		tmp = (0.5 * ((double) M_PI)) / (a * (b * (a + b)));
	} else {
		tmp = (0.5 * (((double) M_PI) / b)) / (a * b);
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (b <= 2.85e+147) {
		tmp = (0.5 * Math.PI) / (a * (b * (a + b)));
	} else {
		tmp = (0.5 * (Math.PI / b)) / (a * b);
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if b <= 2.85e+147:
		tmp = (0.5 * math.pi) / (a * (b * (a + b)))
	else:
		tmp = (0.5 * (math.pi / b)) / (a * b)
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (b <= 2.85e+147)
		tmp = Float64(Float64(0.5 * pi) / Float64(a * Float64(b * Float64(a + b))));
	else
		tmp = Float64(Float64(0.5 * Float64(pi / b)) / Float64(a * b));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 2.85e+147)
		tmp = (0.5 * pi) / (a * (b * (a + b)));
	else
		tmp = (0.5 * (pi / b)) / (a * b);
	end
	tmp_2 = tmp;
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := If[LessEqual[b, 2.85e+147], N[(N[(0.5 * Pi), $MachinePrecision] / N[(a * N[(b * N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[(Pi / b), $MachinePrecision]), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.85 \cdot 10^{+147}:\\
\;\;\;\;\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot \left(a + b\right)\right)}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 2.84999999999999996e147

    1. Initial program 82.6%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative82.6%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*82.6%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/82.6%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*82.6%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity82.6%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg82.6%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac82.6%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval82.6%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified82.6%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative82.6%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares89.4%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.6%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt55.9%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod69.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times69.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval69.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval69.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times69.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod23.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt58.5%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr58.5%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative58.5%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative58.5%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*58.5%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative58.5%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified58.5%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.6%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Step-by-step derivation
      1. *-un-lft-identity99.6%

        \[\leadsto \color{blue}{\left(1 \cdot \frac{1}{a \cdot b}\right)} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
      2. associate-/r*99.5%

        \[\leadsto \left(1 \cdot \color{blue}{\frac{\frac{1}{a}}{b}}\right) \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    11. Applied egg-rr99.5%

      \[\leadsto \color{blue}{\left(1 \cdot \frac{\frac{1}{a}}{b}\right)} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    12. Step-by-step derivation
      1. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{1}{a}}{b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
      2. associate-*l/99.4%

        \[\leadsto \color{blue}{\left(\frac{1}{b} \cdot \frac{1}{a}\right)} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
      3. associate-*r/99.5%

        \[\leadsto \color{blue}{\frac{\frac{1}{b} \cdot 1}{a}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
      4. *-rgt-identity99.5%

        \[\leadsto \frac{\color{blue}{\frac{1}{b}}}{a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    13. Simplified99.5%

      \[\leadsto \color{blue}{\frac{\frac{1}{b}}{a}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    14. Step-by-step derivation
      1. associate-/l/99.6%

        \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
      2. associate-*r/99.6%

        \[\leadsto \frac{1}{a \cdot b} \cdot \color{blue}{\frac{\pi \cdot 0.5}{a + b}} \]
      3. *-commutative99.6%

        \[\leadsto \frac{1}{a \cdot b} \cdot \frac{\color{blue}{0.5 \cdot \pi}}{a + b} \]
      4. frac-times99.1%

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

        \[\leadsto \frac{\color{blue}{0.5 \cdot \pi}}{\left(a \cdot b\right) \cdot \left(a + b\right)} \]
      6. associate-*l*94.4%

        \[\leadsto \frac{0.5 \cdot \pi}{\color{blue}{a \cdot \left(b \cdot \left(a + b\right)\right)}} \]
    15. Applied egg-rr94.4%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot \left(a + b\right)\right)}} \]

    if 2.84999999999999996e147 < b

    1. Initial program 59.4%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative59.4%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*59.4%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/59.4%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*59.4%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity59.4%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg59.4%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac59.4%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval59.4%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified59.4%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative59.4%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares75.2%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.8%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.8%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.8%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt0.0%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt99.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr99.8%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative99.8%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*99.7%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative99.7%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified99.7%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.5%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Taylor expanded in a around 0 99.5%

      \[\leadsto \frac{1}{a \cdot b} \cdot \left(\pi \cdot \color{blue}{\frac{0.5}{b}}\right) \]
    11. Step-by-step derivation
      1. *-commutative99.5%

        \[\leadsto \color{blue}{\left(\pi \cdot \frac{0.5}{b}\right) \cdot \frac{1}{a \cdot b}} \]
      2. div-inv99.8%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot b}} \]
      3. associate-*r/99.8%

        \[\leadsto \frac{\color{blue}{\frac{\pi \cdot 0.5}{b}}}{a \cdot b} \]
      4. *-commutative99.8%

        \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \pi}}{b}}{a \cdot b} \]
      5. *-un-lft-identity99.8%

        \[\leadsto \frac{\frac{0.5 \cdot \pi}{\color{blue}{1 \cdot b}}}{a \cdot b} \]
      6. times-frac99.8%

        \[\leadsto \frac{\color{blue}{\frac{0.5}{1} \cdot \frac{\pi}{b}}}{a \cdot b} \]
      7. metadata-eval99.8%

        \[\leadsto \frac{\color{blue}{0.5} \cdot \frac{\pi}{b}}{a \cdot b} \]
    12. Applied egg-rr99.8%

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

Alternative 3: 89.5% accurate, 1.5× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -7.5 \cdot 10^{-94}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{a}}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{b}}{a \cdot b}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= a -7.5e-94)
   (/ (* 0.5 (/ PI a)) (* a b))
   (/ (* 0.5 (/ PI b)) (* a b))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (a <= -7.5e-94) {
		tmp = (0.5 * (((double) M_PI) / a)) / (a * b);
	} else {
		tmp = (0.5 * (((double) M_PI) / b)) / (a * b);
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (a <= -7.5e-94) {
		tmp = (0.5 * (Math.PI / a)) / (a * b);
	} else {
		tmp = (0.5 * (Math.PI / b)) / (a * b);
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if a <= -7.5e-94:
		tmp = (0.5 * (math.pi / a)) / (a * b)
	else:
		tmp = (0.5 * (math.pi / b)) / (a * b)
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (a <= -7.5e-94)
		tmp = Float64(Float64(0.5 * Float64(pi / a)) / Float64(a * b));
	else
		tmp = Float64(Float64(0.5 * Float64(pi / b)) / Float64(a * b));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -7.5e-94)
		tmp = (0.5 * (pi / a)) / (a * b);
	else
		tmp = (0.5 * (pi / b)) / (a * b);
	end
	tmp_2 = tmp;
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := If[LessEqual[a, -7.5e-94], N[(N[(0.5 * N[(Pi / a), $MachinePrecision]), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[(Pi / b), $MachinePrecision]), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;a \leq -7.5 \cdot 10^{-94}:\\
\;\;\;\;\frac{0.5 \cdot \frac{\pi}{a}}{a \cdot b}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -7.5000000000000003e-94

    1. Initial program 86.9%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative86.9%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*86.9%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/86.9%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*86.9%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity86.9%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg86.9%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac86.9%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval86.9%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified86.9%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative86.9%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares96.0%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.6%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt47.9%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod19.1%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt46.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr46.8%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative46.8%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative46.8%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*46.8%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative46.8%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified46.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.6%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Step-by-step derivation
      1. associate-*l/99.6%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)}{a \cdot b}} \]
      2. *-un-lft-identity99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{0.5}{a + b}}}{a \cdot b} \]
      3. associate-*r/99.6%

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

        \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \pi}}{a + b}}{a \cdot b} \]
    11. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\frac{0.5 \cdot \pi}{a + b}}{a \cdot b}} \]
    12. Taylor expanded in a around inf 83.9%

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

    if -7.5000000000000003e-94 < a

    1. Initial program 78.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative78.3%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*78.3%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/78.3%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*78.3%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity78.3%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg78.3%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac78.3%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval78.3%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified78.3%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative78.3%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares85.0%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.6%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt53.4%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod33.1%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt67.9%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr67.9%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative67.9%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative67.9%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*67.9%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative67.9%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified67.9%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.5%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Taylor expanded in a around 0 67.9%

      \[\leadsto \frac{1}{a \cdot b} \cdot \left(\pi \cdot \color{blue}{\frac{0.5}{b}}\right) \]
    11. Step-by-step derivation
      1. *-commutative67.9%

        \[\leadsto \color{blue}{\left(\pi \cdot \frac{0.5}{b}\right) \cdot \frac{1}{a \cdot b}} \]
      2. div-inv67.9%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot b}} \]
      3. associate-*r/68.0%

        \[\leadsto \frac{\color{blue}{\frac{\pi \cdot 0.5}{b}}}{a \cdot b} \]
      4. *-commutative68.0%

        \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \pi}}{b}}{a \cdot b} \]
      5. *-un-lft-identity68.0%

        \[\leadsto \frac{\frac{0.5 \cdot \pi}{\color{blue}{1 \cdot b}}}{a \cdot b} \]
      6. times-frac68.0%

        \[\leadsto \frac{\color{blue}{\frac{0.5}{1} \cdot \frac{\pi}{b}}}{a \cdot b} \]
      7. metadata-eval68.0%

        \[\leadsto \frac{\color{blue}{0.5} \cdot \frac{\pi}{b}}{a \cdot b} \]
    12. Applied egg-rr68.0%

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

Alternative 4: 89.3% accurate, 1.5× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -1.35 \cdot 10^{-94}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{a}}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= a -1.35e-94)
   (/ (* 0.5 (/ PI a)) (* a b))
   (/ (* 0.5 PI) (* b (* a b)))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (a <= -1.35e-94) {
		tmp = (0.5 * (((double) M_PI) / a)) / (a * b);
	} else {
		tmp = (0.5 * ((double) M_PI)) / (b * (a * b));
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (a <= -1.35e-94) {
		tmp = (0.5 * (Math.PI / a)) / (a * b);
	} else {
		tmp = (0.5 * Math.PI) / (b * (a * b));
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if a <= -1.35e-94:
		tmp = (0.5 * (math.pi / a)) / (a * b)
	else:
		tmp = (0.5 * math.pi) / (b * (a * b))
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (a <= -1.35e-94)
		tmp = Float64(Float64(0.5 * Float64(pi / a)) / Float64(a * b));
	else
		tmp = Float64(Float64(0.5 * pi) / Float64(b * Float64(a * b)));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -1.35e-94)
		tmp = (0.5 * (pi / a)) / (a * b);
	else
		tmp = (0.5 * pi) / (b * (a * b));
	end
	tmp_2 = tmp;
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := If[LessEqual[a, -1.35e-94], N[(N[(0.5 * N[(Pi / a), $MachinePrecision]), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * Pi), $MachinePrecision] / N[(b * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;a \leq -1.35 \cdot 10^{-94}:\\
\;\;\;\;\frac{0.5 \cdot \frac{\pi}{a}}{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 < -1.3500000000000001e-94

    1. Initial program 86.9%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative86.9%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*86.9%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/86.9%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*86.9%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity86.9%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg86.9%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac86.9%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval86.9%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified86.9%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative86.9%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares96.0%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.6%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt47.9%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times58.3%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod19.1%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt46.8%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr46.8%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative46.8%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative46.8%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*46.8%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative46.8%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified46.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.6%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Step-by-step derivation
      1. associate-*l/99.6%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)}{a \cdot b}} \]
      2. *-un-lft-identity99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{0.5}{a + b}}}{a \cdot b} \]
      3. associate-*r/99.6%

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

        \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \pi}}{a + b}}{a \cdot b} \]
    11. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\frac{\frac{0.5 \cdot \pi}{a + b}}{a \cdot b}} \]
    12. Taylor expanded in a around inf 83.9%

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

    if -1.3500000000000001e-94 < a

    1. Initial program 78.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative78.3%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*78.3%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/78.3%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*78.3%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity78.3%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg78.3%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac78.3%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval78.3%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified78.3%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-commutative78.3%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares85.0%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
      4. div-inv99.6%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      5. metadata-eval99.6%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
      6. add-sqr-sqrt53.4%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
      7. sqrt-unprod77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
      8. frac-times77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
      9. metadata-eval77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
      10. metadata-eval77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
      11. frac-times77.2%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
      12. sqrt-unprod33.1%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
      13. add-sqr-sqrt67.9%

        \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
    6. Applied egg-rr67.9%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
    7. Step-by-step derivation
      1. *-commutative67.9%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      2. +-commutative67.9%

        \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
      3. associate-/l*67.9%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
      4. +-commutative67.9%

        \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
    8. Simplified67.9%

      \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
    9. Taylor expanded in b around inf 99.5%

      \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
    10. Taylor expanded in a around 0 67.9%

      \[\leadsto \frac{1}{a \cdot b} \cdot \left(\pi \cdot \color{blue}{\frac{0.5}{b}}\right) \]
    11. Step-by-step derivation
      1. associate-*r/68.0%

        \[\leadsto \frac{1}{a \cdot b} \cdot \color{blue}{\frac{\pi \cdot 0.5}{b}} \]
      2. *-commutative68.0%

        \[\leadsto \frac{1}{a \cdot b} \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b} \]
      3. frac-times68.0%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(0.5 \cdot \pi\right)}{\left(a \cdot b\right) \cdot b}} \]
      4. *-un-lft-identity68.0%

        \[\leadsto \frac{\color{blue}{0.5 \cdot \pi}}{\left(a \cdot b\right) \cdot b} \]
    12. Applied egg-rr68.0%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.35 \cdot 10^{-94}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{a}}{a \cdot b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 99.7% accurate, 1.9× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5 \cdot \frac{\pi}{a \cdot b}}{a + b} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (* 0.5 (/ PI (* a b))) (+ a b)))
assert(a < b);
double code(double a, double b) {
	return (0.5 * (((double) M_PI) / (a * b))) / (a + b);
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 * (Math.PI / (a * b))) / (a + b);
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 * (math.pi / (a * b))) / (a + b)
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 * Float64(pi / Float64(a * b))) / Float64(a + b))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 * (pi / (a * b))) / (a + b);
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5 \cdot \frac{\pi}{a \cdot b}}{a + b}
\end{array}
Derivation
  1. Initial program 80.9%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*80.9%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/80.9%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity80.9%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified80.9%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity80.9%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares88.3%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    3. times-frac99.5%

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
  6. Applied egg-rr61.5%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/61.6%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}}{b + a}} \]
    2. *-lft-identity61.6%

      \[\leadsto \frac{\color{blue}{\frac{\pi \cdot \left(0.5 \cdot \left(\frac{1}{a} + \frac{1}{b}\right)\right)}{b - a}}}{b + a} \]
    3. associate-*r*61.6%

      \[\leadsto \frac{\frac{\color{blue}{\left(\pi \cdot 0.5\right) \cdot \left(\frac{1}{a} + \frac{1}{b}\right)}}{b - a}}{b + a} \]
    4. distribute-rgt-out61.6%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1}{a} \cdot \left(\pi \cdot 0.5\right) + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}}{b - a}}{b + a} \]
    5. associate-*l/61.6%

      \[\leadsto \frac{\frac{\color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{a}} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    6. *-lft-identity61.6%

      \[\leadsto \frac{\frac{\frac{\color{blue}{\pi \cdot 0.5}}{a} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    7. *-commutative61.6%

      \[\leadsto \frac{\frac{\frac{\color{blue}{0.5 \cdot \pi}}{a} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    8. associate-*r/61.6%

      \[\leadsto \frac{\frac{\color{blue}{0.5 \cdot \frac{\pi}{a}} + \frac{1}{b} \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a} \]
    9. associate-*l/61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{b}}}{b - a}}{b + a} \]
    10. *-lft-identity61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \frac{\color{blue}{\pi \cdot 0.5}}{b}}{b - a}}{b + a} \]
    11. *-commutative61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \frac{\color{blue}{0.5 \cdot \pi}}{b}}{b - a}}{b + a} \]
    12. associate-*r/61.6%

      \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{a} + \color{blue}{0.5 \cdot \frac{\pi}{b}}}{b - a}}{b + a} \]
    13. fma-define61.6%

      \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(0.5, \frac{\pi}{a}, 0.5 \cdot \frac{\pi}{b}\right)}}{b - a}}{b + a} \]
    14. associate-*r/61.6%

      \[\leadsto \frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \color{blue}{\frac{0.5 \cdot \pi}{b}}\right)}{b - a}}{b + a} \]
    15. +-commutative61.6%

      \[\leadsto \frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \frac{0.5 \cdot \pi}{b}\right)}{b - a}}{\color{blue}{a + b}} \]
  8. Simplified61.6%

    \[\leadsto \color{blue}{\frac{\frac{\mathsf{fma}\left(0.5, \frac{\pi}{a}, \frac{0.5 \cdot \pi}{b}\right)}{b - a}}{a + b}} \]
  9. Taylor expanded in a around 0 99.6%

    \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\pi}{a \cdot b}}}{a + b} \]
  10. Add Preprocessing

Alternative 6: 99.1% accurate, 1.9× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5 \cdot \pi}{\left(a + b\right) \cdot \left(a \cdot b\right)} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (* 0.5 PI) (* (+ a b) (* a b))))
assert(a < b);
double code(double a, double b) {
	return (0.5 * ((double) M_PI)) / ((a + b) * (a * b));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 * Math.PI) / ((a + b) * (a * b));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 * math.pi) / ((a + b) * (a * b))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 * pi) / Float64(Float64(a + b) * Float64(a * b)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 * pi) / ((a + b) * (a * b));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 * Pi), $MachinePrecision] / N[(N[(a + b), $MachinePrecision] * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5 \cdot \pi}{\left(a + b\right) \cdot \left(a \cdot b\right)}
\end{array}
Derivation
  1. Initial program 80.9%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*80.9%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/80.9%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity80.9%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified80.9%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares88.3%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    3. times-frac99.6%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
    4. div-inv99.6%

      \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
    5. metadata-eval99.6%

      \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
    6. add-sqr-sqrt51.7%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
    7. sqrt-unprod71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
    8. frac-times71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
    9. metadata-eval71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
    10. metadata-eval71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
    11. frac-times71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
    12. sqrt-unprod28.9%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
    13. add-sqr-sqrt61.6%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
  6. Applied egg-rr61.6%

    \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
  7. Step-by-step derivation
    1. *-commutative61.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
    2. +-commutative61.6%

      \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
    3. associate-/l*61.5%

      \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
    4. +-commutative61.5%

      \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
  8. Simplified61.5%

    \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
  9. Taylor expanded in b around inf 99.6%

    \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
  10. Step-by-step derivation
    1. associate-*r/99.6%

      \[\leadsto \frac{1}{a \cdot b} \cdot \color{blue}{\frac{\pi \cdot 0.5}{a + b}} \]
    2. +-commutative99.6%

      \[\leadsto \frac{1}{a \cdot b} \cdot \frac{\pi \cdot 0.5}{\color{blue}{b + a}} \]
    3. frac-times99.2%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{\left(a \cdot b\right) \cdot \left(b + a\right)}} \]
    4. *-un-lft-identity99.2%

      \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{\left(a \cdot b\right) \cdot \left(b + a\right)} \]
    5. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \pi}}{\left(a \cdot b\right) \cdot \left(b + a\right)} \]
    6. +-commutative99.2%

      \[\leadsto \frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot \color{blue}{\left(a + b\right)}} \]
  11. Applied egg-rr99.2%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot \left(a + b\right)}} \]
  12. Final simplification99.2%

    \[\leadsto \frac{0.5 \cdot \pi}{\left(a + b\right) \cdot \left(a \cdot b\right)} \]
  13. Add Preprocessing

Alternative 7: 62.2% accurate, 2.3× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (* 0.5 PI) (* b (* a b))))
assert(a < b);
double code(double a, double b) {
	return (0.5 * ((double) M_PI)) / (b * (a * b));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 * Math.PI) / (b * (a * b));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 * math.pi) / (b * (a * b))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 * pi) / Float64(b * Float64(a * b)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 * pi) / (b * (a * b));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 * Pi), $MachinePrecision] / N[(b * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)}
\end{array}
Derivation
  1. Initial program 80.9%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*80.9%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/80.9%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity80.9%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg80.9%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval80.9%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified80.9%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-commutative80.9%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares88.3%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} + \frac{-1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    3. times-frac99.6%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a}} \]
    4. div-inv99.6%

      \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
    5. metadata-eval99.6%

      \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{b + a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b - a} \]
    6. add-sqr-sqrt51.7%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}}{b - a} \]
    7. sqrt-unprod71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}}{b - a} \]
    8. frac-times71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}}{b - a} \]
    9. metadata-eval71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}}{b - a} \]
    10. metadata-eval71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}}{b - a} \]
    11. frac-times71.5%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}}{b - a} \]
    12. sqrt-unprod28.9%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}}{b - a} \]
    13. add-sqr-sqrt61.6%

      \[\leadsto \frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \color{blue}{\frac{1}{b}}}{b - a} \]
  6. Applied egg-rr61.6%

    \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{b + a} \cdot \frac{\frac{1}{a} + \frac{1}{b}}{b - a}} \]
  7. Step-by-step derivation
    1. *-commutative61.6%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} + \frac{1}{b}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
    2. +-commutative61.6%

      \[\leadsto \frac{\color{blue}{\frac{1}{b} + \frac{1}{a}}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a} \]
    3. associate-/l*61.5%

      \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \color{blue}{\left(\pi \cdot \frac{0.5}{b + a}\right)} \]
    4. +-commutative61.5%

      \[\leadsto \frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{\color{blue}{a + b}}\right) \]
  8. Simplified61.5%

    \[\leadsto \color{blue}{\frac{\frac{1}{b} + \frac{1}{a}}{b - a} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right)} \]
  9. Taylor expanded in b around inf 99.6%

    \[\leadsto \color{blue}{\frac{1}{a \cdot b}} \cdot \left(\pi \cdot \frac{0.5}{a + b}\right) \]
  10. Taylor expanded in a around 0 59.5%

    \[\leadsto \frac{1}{a \cdot b} \cdot \left(\pi \cdot \color{blue}{\frac{0.5}{b}}\right) \]
  11. Step-by-step derivation
    1. associate-*r/59.6%

      \[\leadsto \frac{1}{a \cdot b} \cdot \color{blue}{\frac{\pi \cdot 0.5}{b}} \]
    2. *-commutative59.6%

      \[\leadsto \frac{1}{a \cdot b} \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b} \]
    3. frac-times59.3%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(0.5 \cdot \pi\right)}{\left(a \cdot b\right) \cdot b}} \]
    4. *-un-lft-identity59.3%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \pi}}{\left(a \cdot b\right) \cdot b} \]
  12. Applied egg-rr59.3%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a \cdot b\right) \cdot b}} \]
  13. Final simplification59.3%

    \[\leadsto \frac{0.5 \cdot \pi}{b \cdot \left(a \cdot b\right)} \]
  14. Add Preprocessing

Reproduce

?
herbie shell --seed 2024129 
(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))))