NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.4% → 99.6%
Time: 11.7s
Alternatives: 10
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 10 alternatives:

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

Initial Program: 78.4% 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: 99.6% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;b \leq 5 \cdot 10^{+89}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot \left(a + b\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b} \cdot \frac{0.5}{a \cdot \left(b - a\right)}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= b 5e+89)
   (* (/ 0.5 a) (/ PI (* b (+ a b))))
   (* (/ PI b) (/ 0.5 (* a (- b a))))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (b <= 5e+89) {
		tmp = (0.5 / a) * (((double) M_PI) / (b * (a + b)));
	} else {
		tmp = (((double) M_PI) / b) * (0.5 / (a * (b - a)));
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (b <= 5e+89) {
		tmp = (0.5 / a) * (Math.PI / (b * (a + b)));
	} else {
		tmp = (Math.PI / b) * (0.5 / (a * (b - a)));
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if b <= 5e+89:
		tmp = (0.5 / a) * (math.pi / (b * (a + b)))
	else:
		tmp = (math.pi / b) * (0.5 / (a * (b - a)))
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (b <= 5e+89)
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(b * Float64(a + b))));
	else
		tmp = Float64(Float64(pi / b) * Float64(0.5 / Float64(a * Float64(b - a))));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 5e+89)
		tmp = (0.5 / a) * (pi / (b * (a + b)));
	else
		tmp = (pi / b) * (0.5 / (a * (b - a)));
	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, 5e+89], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(b * N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(Pi / b), $MachinePrecision] * N[(0.5 / N[(a * N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 5 \cdot 10^{+89}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot \left(a + b\right)}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 4.99999999999999983e89

    1. Initial program 81.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative81.8%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*81.8%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/81.8%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-/l*81.8%

        \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\frac{b \cdot b - a \cdot a}{1}}} \]
      5. /-rgt-identity81.8%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\color{blue}{b \cdot b - a \cdot a}} \]
      6. associate-/l*81.8%

        \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \]
      7. difference-of-squares89.6%

        \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\frac{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}}{\frac{\pi}{2}}} \]
      8. associate-/l*89.6%

        \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\color{blue}{\frac{b + a}{\frac{\frac{\pi}{2}}{b - a}}}} \]
      9. associate-/l*99.5%

        \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
      10. associate-*r/91.0%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
      11. sub-neg91.0%

        \[\leadsto \color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
      12. distribute-neg-frac91.0%

        \[\leadsto \left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
      13. metadata-eval91.0%

        \[\leadsto \left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    3. Simplified91.0%

      \[\leadsto \color{blue}{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    4. Taylor expanded in a around 0 61.4%

      \[\leadsto \color{blue}{\frac{1}{a}} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    5. Taylor expanded in b around inf 96.5%

      \[\leadsto \frac{1}{a} \cdot \frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{b + a} \]
    6. Step-by-step derivation
      1. expm1-log1p-u72.6%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)\right)} \]
      2. expm1-udef51.1%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)} - 1} \]
      3. frac-times51.1%

        \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{1 \cdot \left(0.5 \cdot \frac{\pi}{b}\right)}{a \cdot \left(b + a\right)}}\right)} - 1 \]
      4. *-un-lft-identity51.1%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{a \cdot \left(b + a\right)}\right)} - 1 \]
      5. times-frac51.1%

        \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{b + a}}\right)} - 1 \]
      6. +-commutative51.1%

        \[\leadsto e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{a + b}}\right)} - 1 \]
    7. Applied egg-rr51.1%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)} - 1} \]
    8. Step-by-step derivation
      1. expm1-def72.7%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)\right)} \]
      2. expm1-log1p96.5%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}} \]
      3. associate-/l/95.9%

        \[\leadsto \frac{0.5}{a} \cdot \color{blue}{\frac{\pi}{\left(a + b\right) \cdot b}} \]
    9. Simplified95.9%

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

    if 4.99999999999999983e89 < b

    1. Initial program 51.6%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. associate-*r/51.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity51.6%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. associate-*l/51.6%

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

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      5. *-commutative75.1%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
      7. sub-neg99.8%

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

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

        \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
    4. Step-by-step derivation
      1. associate-*l/99.8%

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

        \[\leadsto \frac{\color{blue}{\left(\pi \cdot \frac{1}{2}\right)} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a} \]
      3. metadata-eval99.8%

        \[\leadsto \frac{\left(\pi \cdot \color{blue}{0.5}\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a} \]
    5. Applied egg-rr99.8%

      \[\leadsto \color{blue}{\frac{\left(\pi \cdot 0.5\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a}} \]
    6. Taylor expanded in a around 0 99.8%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\pi}{a \cdot b}}}{b - a} \]
    7. Step-by-step derivation
      1. associate-/r*99.9%

        \[\leadsto \frac{0.5 \cdot \color{blue}{\frac{\frac{\pi}{a}}{b}}}{b - a} \]
    8. Simplified99.9%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\frac{\pi}{a}}{b}}}{b - a} \]
    9. Step-by-step derivation
      1. *-commutative99.9%

        \[\leadsto \frac{\color{blue}{\frac{\frac{\pi}{a}}{b} \cdot 0.5}}{b - a} \]
      2. add-sqr-sqrt99.9%

        \[\leadsto \frac{\frac{\frac{\pi}{a}}{\color{blue}{\sqrt{b} \cdot \sqrt{b}}} \cdot 0.5}{b - a} \]
      3. sqrt-unprod75.2%

        \[\leadsto \frac{\frac{\frac{\pi}{a}}{\color{blue}{\sqrt{b \cdot b}}} \cdot 0.5}{b - a} \]
      4. sqr-neg75.2%

        \[\leadsto \frac{\frac{\frac{\pi}{a}}{\sqrt{\color{blue}{\left(-b\right) \cdot \left(-b\right)}}} \cdot 0.5}{b - a} \]
      5. sqrt-unprod0.0%

        \[\leadsto \frac{\frac{\frac{\pi}{a}}{\color{blue}{\sqrt{-b} \cdot \sqrt{-b}}} \cdot 0.5}{b - a} \]
      6. add-sqr-sqrt63.4%

        \[\leadsto \frac{\frac{\frac{\pi}{a}}{\color{blue}{-b}} \cdot 0.5}{b - a} \]
      7. associate-/r*63.4%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{a \cdot \left(-b\right)}} \cdot 0.5}{b - a} \]
      8. associate-*r/63.4%

        \[\leadsto \color{blue}{\frac{\pi}{a \cdot \left(-b\right)} \cdot \frac{0.5}{b - a}} \]
      9. associate-*l/63.4%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b - a}}{a \cdot \left(-b\right)}} \]
      10. *-commutative63.4%

        \[\leadsto \frac{\pi \cdot \frac{0.5}{b - a}}{\color{blue}{\left(-b\right) \cdot a}} \]
      11. times-frac63.4%

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

        \[\leadsto \frac{\pi}{\color{blue}{\sqrt{-b} \cdot \sqrt{-b}}} \cdot \frac{\frac{0.5}{b - a}}{a} \]
      13. sqrt-unprod75.2%

        \[\leadsto \frac{\pi}{\color{blue}{\sqrt{\left(-b\right) \cdot \left(-b\right)}}} \cdot \frac{\frac{0.5}{b - a}}{a} \]
      14. sqr-neg75.2%

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

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

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

      \[\leadsto \color{blue}{\frac{\pi}{b} \cdot \frac{\frac{0.5}{b - a}}{a}} \]
    11. Step-by-step derivation
      1. associate-/l/99.8%

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

      \[\leadsto \color{blue}{\frac{\pi}{b} \cdot \frac{0.5}{a \cdot \left(b - a\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification96.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 5 \cdot 10^{+89}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot \left(a + b\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b} \cdot \frac{0.5}{a \cdot \left(b - a\right)}\\ \end{array} \]

Alternative 2: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\left(\pi \cdot 0.5\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{a + b}}{b - a} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (/ (* (* PI 0.5) (/ (+ (/ 1.0 a) (/ -1.0 b)) (+ a b))) (- b a)))
assert(a < b);
double code(double a, double b) {
	return ((((double) M_PI) * 0.5) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a);
}
assert a < b;
public static double code(double a, double b) {
	return ((Math.PI * 0.5) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a);
}
[a, b] = sort([a, b])
def code(a, b):
	return ((math.pi * 0.5) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a)
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(Float64(pi * 0.5) * Float64(Float64(Float64(1.0 / a) + Float64(-1.0 / b)) / Float64(a + b))) / Float64(b - a))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = ((pi * 0.5) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a);
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(N[(Pi * 0.5), $MachinePrecision] * N[(N[(N[(1.0 / a), $MachinePrecision] + N[(-1.0 / b), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{\left(\pi \cdot 0.5\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{a + b}}{b - a}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity75.8%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. associate-*l/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
    4. difference-of-squares86.7%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    5. *-commutative86.7%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
    7. sub-neg99.5%

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

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

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
  4. Step-by-step derivation
    1. associate-*l/99.6%

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

      \[\leadsto \frac{\color{blue}{\left(\pi \cdot \frac{1}{2}\right)} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a} \]
    3. metadata-eval99.6%

      \[\leadsto \frac{\left(\pi \cdot \color{blue}{0.5}\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a} \]
  5. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\frac{\left(\pi \cdot 0.5\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}}{b - a}} \]
  6. Final simplification99.6%

    \[\leadsto \frac{\left(\pi \cdot 0.5\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{a + b}}{b - a} \]

Alternative 3: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\frac{1}{a} + \frac{-1}{b}}{a + b} \cdot \frac{\frac{\pi}{2}}{b - a} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (* (/ (+ (/ 1.0 a) (/ -1.0 b)) (+ a b)) (/ (/ PI 2.0) (- b a))))
assert(a < b);
double code(double a, double b) {
	return (((1.0 / a) + (-1.0 / b)) / (a + b)) * ((((double) M_PI) / 2.0) / (b - a));
}
assert a < b;
public static double code(double a, double b) {
	return (((1.0 / a) + (-1.0 / b)) / (a + b)) * ((Math.PI / 2.0) / (b - a));
}
[a, b] = sort([a, b])
def code(a, b):
	return (((1.0 / a) + (-1.0 / b)) / (a + b)) * ((math.pi / 2.0) / (b - a))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(Float64(Float64(1.0 / a) + Float64(-1.0 / b)) / Float64(a + b)) * Float64(Float64(pi / 2.0) / Float64(b - a)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (((1.0 / a) + (-1.0 / b)) / (a + b)) * ((pi / 2.0) / (b - a));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(N[(N[(1.0 / a), $MachinePrecision] + N[(-1.0 / b), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision] * N[(N[(Pi / 2.0), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{\frac{1}{a} + \frac{-1}{b}}{a + b} \cdot \frac{\frac{\pi}{2}}{b - a}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity75.8%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. associate-*l/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
    4. difference-of-squares86.7%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    5. *-commutative86.7%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
    7. sub-neg99.5%

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

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

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
  4. Final simplification99.5%

    \[\leadsto \frac{\frac{1}{a} + \frac{-1}{b}}{a + b} \cdot \frac{\frac{\pi}{2}}{b - a} \]

Alternative 4: 71.9% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;b \leq 5 \cdot 10^{+102}:\\ \;\;\;\;\frac{\frac{0.5}{a}}{\frac{a \cdot b}{\pi}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{a \cdot \left(-b\right)} \cdot \frac{0.5}{b}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= b 5e+102)
   (/ (/ 0.5 a) (/ (* a b) PI))
   (* (/ PI (* a (- b))) (/ 0.5 b))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (b <= 5e+102) {
		tmp = (0.5 / a) / ((a * b) / ((double) M_PI));
	} else {
		tmp = (((double) M_PI) / (a * -b)) * (0.5 / b);
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (b <= 5e+102) {
		tmp = (0.5 / a) / ((a * b) / Math.PI);
	} else {
		tmp = (Math.PI / (a * -b)) * (0.5 / b);
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if b <= 5e+102:
		tmp = (0.5 / a) / ((a * b) / math.pi)
	else:
		tmp = (math.pi / (a * -b)) * (0.5 / b)
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (b <= 5e+102)
		tmp = Float64(Float64(0.5 / a) / Float64(Float64(a * b) / pi));
	else
		tmp = Float64(Float64(pi / Float64(a * Float64(-b))) * Float64(0.5 / b));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 5e+102)
		tmp = (0.5 / a) / ((a * b) / pi);
	else
		tmp = (pi / (a * -b)) * (0.5 / 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, 5e+102], N[(N[(0.5 / a), $MachinePrecision] / N[(N[(a * b), $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(Pi / N[(a * (-b)), $MachinePrecision]), $MachinePrecision] * N[(0.5 / b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;b \leq 5 \cdot 10^{+102}:\\
\;\;\;\;\frac{\frac{0.5}{a}}{\frac{a \cdot b}{\pi}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 5e102

    1. Initial program 81.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. associate-*r/81.8%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity81.8%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. associate-*l/81.8%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
      4. difference-of-squares89.6%

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      5. *-commutative89.6%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
      7. sub-neg99.5%

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

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

        \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
    4. Taylor expanded in a around inf 67.0%

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \color{blue}{\frac{-1}{a \cdot b}} \]
    5. Taylor expanded in b around 0 65.1%

      \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{\pi}{a}\right)} \cdot \frac{-1}{a \cdot b} \]
    6. Step-by-step derivation
      1. associate-*r/65.1%

        \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
    7. Simplified65.1%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
    8. Step-by-step derivation
      1. associate-/l*65.1%

        \[\leadsto \color{blue}{\frac{-0.5}{\frac{a}{\pi}}} \cdot \frac{-1}{a \cdot b} \]
      2. associate-/r*65.1%

        \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \color{blue}{\frac{\frac{-1}{a}}{b}} \]
      3. frac-times65.1%

        \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
    9. Applied egg-rr65.1%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
    10. Step-by-step derivation
      1. associate-*r/65.1%

        \[\leadsto \frac{\color{blue}{\frac{-0.5 \cdot -1}{a}}}{\frac{a}{\pi} \cdot b} \]
      2. metadata-eval65.1%

        \[\leadsto \frac{\frac{\color{blue}{0.5}}{a}}{\frac{a}{\pi} \cdot b} \]
      3. associate-*l/65.1%

        \[\leadsto \frac{\frac{0.5}{a}}{\color{blue}{\frac{a \cdot b}{\pi}}} \]
      4. associate-/l*65.1%

        \[\leadsto \frac{\frac{0.5}{a}}{\color{blue}{\frac{a}{\frac{\pi}{b}}}} \]
    11. Simplified65.1%

      \[\leadsto \color{blue}{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}} \]
    12. Taylor expanded in a around 0 65.1%

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

    if 5e102 < b

    1. Initial program 51.6%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. associate-*r/51.6%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity51.6%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. associate-*l/51.6%

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

        \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      5. *-commutative75.1%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
      7. sub-neg99.8%

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

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

        \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
    4. Taylor expanded in a around inf 63.4%

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \color{blue}{\frac{-1}{a \cdot b}} \]
    5. Step-by-step derivation
      1. *-commutative63.4%

        \[\leadsto \color{blue}{\frac{-1}{a \cdot b} \cdot \frac{\frac{\pi}{2}}{b - a}} \]
      2. frac-2neg63.4%

        \[\leadsto \color{blue}{\frac{--1}{-a \cdot b}} \cdot \frac{\frac{\pi}{2}}{b - a} \]
      3. metadata-eval63.4%

        \[\leadsto \frac{\color{blue}{1}}{-a \cdot b} \cdot \frac{\frac{\pi}{2}}{b - a} \]
      4. frac-times63.4%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{\pi}{2}}{\left(-a \cdot b\right) \cdot \left(b - a\right)}} \]
      5. *-un-lft-identity63.4%

        \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{\left(-a \cdot b\right) \cdot \left(b - a\right)} \]
      6. div-inv63.4%

        \[\leadsto \frac{\color{blue}{\pi \cdot \frac{1}{2}}}{\left(-a \cdot b\right) \cdot \left(b - a\right)} \]
      7. metadata-eval63.4%

        \[\leadsto \frac{\pi \cdot \color{blue}{0.5}}{\left(-a \cdot b\right) \cdot \left(b - a\right)} \]
    6. Applied egg-rr63.4%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{\left(-a \cdot b\right) \cdot \left(b - a\right)}} \]
    7. Step-by-step derivation
      1. times-frac63.4%

        \[\leadsto \color{blue}{\frac{\pi}{-a \cdot b} \cdot \frac{0.5}{b - a}} \]
      2. distribute-rgt-neg-in63.4%

        \[\leadsto \frac{\pi}{\color{blue}{a \cdot \left(-b\right)}} \cdot \frac{0.5}{b - a} \]
    8. Simplified63.4%

      \[\leadsto \color{blue}{\frac{\pi}{a \cdot \left(-b\right)} \cdot \frac{0.5}{b - a}} \]
    9. Taylor expanded in b around inf 63.4%

      \[\leadsto \frac{\pi}{a \cdot \left(-b\right)} \cdot \color{blue}{\frac{0.5}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 5 \cdot 10^{+102}:\\ \;\;\;\;\frac{\frac{0.5}{a}}{\frac{a \cdot b}{\pi}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{a \cdot \left(-b\right)} \cdot \frac{0.5}{b}\\ \end{array} \]

Alternative 5: 93.8% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5}{a} \cdot \frac{\pi}{b \cdot \left(a + b\right)} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (* (/ 0.5 a) (/ PI (* b (+ a b)))))
assert(a < b);
double code(double a, double b) {
	return (0.5 / a) * (((double) M_PI) / (b * (a + b)));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 / a) * (Math.PI / (b * (a + b)));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 / a) * (math.pi / (b * (a + b)))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 / a) * Float64(pi / Float64(b * Float64(a + b))))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 / a) * (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 / a), $MachinePrecision] * N[(Pi / N[(b * N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5}{a} \cdot \frac{\pi}{b \cdot \left(a + b\right)}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative75.8%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*75.8%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\frac{b \cdot b - a \cdot a}{1}}} \]
    5. /-rgt-identity75.8%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\color{blue}{b \cdot b - a \cdot a}} \]
    6. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \]
    7. difference-of-squares86.7%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\frac{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}}{\frac{\pi}{2}}} \]
    8. associate-/l*86.8%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\color{blue}{\frac{b + a}{\frac{\frac{\pi}{2}}{b - a}}}} \]
    9. associate-/l*99.5%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    10. associate-*r/88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    11. sub-neg88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    12. distribute-neg-frac88.2%

      \[\leadsto \left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    13. metadata-eval88.2%

      \[\leadsto \left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  3. Simplified88.2%

    \[\leadsto \color{blue}{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
  4. Taylor expanded in a around 0 64.5%

    \[\leadsto \color{blue}{\frac{1}{a}} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  5. Taylor expanded in b around inf 92.6%

    \[\leadsto \frac{1}{a} \cdot \frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{b + a} \]
  6. Step-by-step derivation
    1. expm1-log1p-u72.7%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)\right)} \]
    2. expm1-udef53.6%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)} - 1} \]
    3. frac-times53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{1 \cdot \left(0.5 \cdot \frac{\pi}{b}\right)}{a \cdot \left(b + a\right)}}\right)} - 1 \]
    4. *-un-lft-identity53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{a \cdot \left(b + a\right)}\right)} - 1 \]
    5. times-frac53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{b + a}}\right)} - 1 \]
    6. +-commutative53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{a + b}}\right)} - 1 \]
  7. Applied egg-rr53.6%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)} - 1} \]
  8. Step-by-step derivation
    1. expm1-def72.7%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)\right)} \]
    2. expm1-log1p92.6%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}} \]
    3. associate-/l/91.8%

      \[\leadsto \frac{0.5}{a} \cdot \color{blue}{\frac{\pi}{\left(a + b\right) \cdot b}} \]
  9. Simplified91.8%

    \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{\left(a + b\right) \cdot b}} \]
  10. Final simplification91.8%

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

Alternative 6: 99.0% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\pi}{\left(a + b\right) \cdot \left(2 \cdot \left(a \cdot b\right)\right)} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ PI (* (+ a b) (* 2.0 (* a b)))))
assert(a < b);
double code(double a, double b) {
	return ((double) M_PI) / ((a + b) * (2.0 * (a * b)));
}
assert a < b;
public static double code(double a, double b) {
	return Math.PI / ((a + b) * (2.0 * (a * b)));
}
[a, b] = sort([a, b])
def code(a, b):
	return math.pi / ((a + b) * (2.0 * (a * b)))
a, b = sort([a, b])
function code(a, b)
	return Float64(pi / Float64(Float64(a + b) * Float64(2.0 * Float64(a * b))))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = pi / ((a + b) * (2.0 * (a * b)));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(Pi / N[(N[(a + b), $MachinePrecision] * N[(2.0 * N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{\pi}{\left(a + b\right) \cdot \left(2 \cdot \left(a \cdot b\right)\right)}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative75.8%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*75.8%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\frac{b \cdot b - a \cdot a}{1}}} \]
    5. /-rgt-identity75.8%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\color{blue}{b \cdot b - a \cdot a}} \]
    6. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \]
    7. difference-of-squares86.7%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\frac{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}}{\frac{\pi}{2}}} \]
    8. associate-/l*86.8%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\color{blue}{\frac{b + a}{\frac{\frac{\pi}{2}}{b - a}}}} \]
    9. associate-/l*99.5%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    10. associate-*r/88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    11. sub-neg88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    12. distribute-neg-frac88.2%

      \[\leadsto \left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    13. metadata-eval88.2%

      \[\leadsto \left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  3. Simplified88.2%

    \[\leadsto \color{blue}{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
  4. Taylor expanded in a around 0 64.5%

    \[\leadsto \color{blue}{\frac{1}{a}} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  5. Step-by-step derivation
    1. associate-*r/71.4%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} \cdot \frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    2. associate-/l/71.4%

      \[\leadsto \frac{\frac{1}{a} \cdot \color{blue}{\frac{\pi}{\left(b - a\right) \cdot 2}}}{b + a} \]
    3. frac-times71.5%

      \[\leadsto \frac{\color{blue}{\frac{1 \cdot \pi}{a \cdot \left(\left(b - a\right) \cdot 2\right)}}}{b + a} \]
    4. *-un-lft-identity71.5%

      \[\leadsto \frac{\frac{\color{blue}{\pi}}{a \cdot \left(\left(b - a\right) \cdot 2\right)}}{b + a} \]
    5. +-commutative71.5%

      \[\leadsto \frac{\frac{\pi}{a \cdot \left(\left(b - a\right) \cdot 2\right)}}{\color{blue}{a + b}} \]
  6. Applied egg-rr71.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{a \cdot \left(\left(b - a\right) \cdot 2\right)}}{a + b}} \]
  7. Step-by-step derivation
    1. associate-/l/71.3%

      \[\leadsto \color{blue}{\frac{\pi}{\left(a + b\right) \cdot \left(a \cdot \left(\left(b - a\right) \cdot 2\right)\right)}} \]
    2. *-commutative71.3%

      \[\leadsto \frac{\pi}{\left(a + b\right) \cdot \left(a \cdot \color{blue}{\left(2 \cdot \left(b - a\right)\right)}\right)} \]
  8. Simplified71.3%

    \[\leadsto \color{blue}{\frac{\pi}{\left(a + b\right) \cdot \left(a \cdot \left(2 \cdot \left(b - a\right)\right)\right)}} \]
  9. Taylor expanded in a around 0 99.2%

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

    \[\leadsto \frac{\pi}{\left(a + b\right) \cdot \left(2 \cdot \left(a \cdot b\right)\right)} \]

Alternative 7: 31.0% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{-0.5}{a} \cdot \frac{\frac{\pi}{b}}{a} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (* (/ -0.5 a) (/ (/ PI b) a)))
assert(a < b);
double code(double a, double b) {
	return (-0.5 / a) * ((((double) M_PI) / b) / a);
}
assert a < b;
public static double code(double a, double b) {
	return (-0.5 / a) * ((Math.PI / b) / a);
}
[a, b] = sort([a, b])
def code(a, b):
	return (-0.5 / a) * ((math.pi / b) / a)
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(-0.5 / a) * Float64(Float64(pi / b) / a))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (-0.5 / a) * ((pi / b) / a);
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(-0.5 / a), $MachinePrecision] * N[(N[(Pi / b), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{-0.5}{a} \cdot \frac{\frac{\pi}{b}}{a}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity75.8%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. associate-*l/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
    4. difference-of-squares86.7%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    5. *-commutative86.7%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
    7. sub-neg99.5%

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

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

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
  4. Taylor expanded in a around inf 66.3%

    \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \color{blue}{\frac{-1}{a \cdot b}} \]
  5. Taylor expanded in b around 0 61.5%

    \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{\pi}{a}\right)} \cdot \frac{-1}{a \cdot b} \]
  6. Step-by-step derivation
    1. associate-*r/61.5%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  7. Simplified61.5%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  8. Step-by-step derivation
    1. associate-/l*61.5%

      \[\leadsto \color{blue}{\frac{-0.5}{\frac{a}{\pi}}} \cdot \frac{-1}{a \cdot b} \]
    2. frac-2neg61.5%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \color{blue}{\frac{--1}{-a \cdot b}} \]
    3. metadata-eval61.5%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \frac{\color{blue}{1}}{-a \cdot b} \]
    4. distribute-rgt-neg-out61.5%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \frac{1}{\color{blue}{a \cdot \left(-b\right)}} \]
    5. frac-times61.2%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot 1}{\frac{a}{\pi} \cdot \left(a \cdot \left(-b\right)\right)}} \]
    6. metadata-eval61.2%

      \[\leadsto \frac{\color{blue}{-0.5}}{\frac{a}{\pi} \cdot \left(a \cdot \left(-b\right)\right)} \]
    7. add-sqr-sqrt29.9%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot \color{blue}{\left(\sqrt{-b} \cdot \sqrt{-b}\right)}\right)} \]
    8. sqrt-unprod49.3%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot \color{blue}{\sqrt{\left(-b\right) \cdot \left(-b\right)}}\right)} \]
    9. sqr-neg49.3%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot \sqrt{\color{blue}{b \cdot b}}\right)} \]
    10. sqrt-unprod18.9%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot \color{blue}{\left(\sqrt{b} \cdot \sqrt{b}\right)}\right)} \]
    11. add-sqr-sqrt35.3%

      \[\leadsto \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot \color{blue}{b}\right)} \]
  9. Applied egg-rr35.3%

    \[\leadsto \color{blue}{\frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot b\right)}} \]
  10. Step-by-step derivation
    1. add-sqr-sqrt32.0%

      \[\leadsto \color{blue}{\sqrt{\frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot b\right)}} \cdot \sqrt{\frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot b\right)}}} \]
    2. sqrt-unprod45.5%

      \[\leadsto \color{blue}{\sqrt{\frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot b\right)} \cdot \frac{-0.5}{\frac{a}{\pi} \cdot \left(a \cdot b\right)}}} \]
    3. frac-times45.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-0.5 \cdot -0.5}{\left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right) \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}}} \]
    4. metadata-eval45.5%

      \[\leadsto \sqrt{\frac{\color{blue}{0.25}}{\left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right) \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}} \]
    5. metadata-eval45.5%

      \[\leadsto \sqrt{\frac{\color{blue}{0.5 \cdot 0.5}}{\left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right) \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}} \]
    6. *-commutative45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\left(\frac{a}{\pi} \cdot \color{blue}{\left(b \cdot a\right)}\right) \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}} \]
    7. associate-*r*45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\color{blue}{\left(\left(\frac{a}{\pi} \cdot b\right) \cdot a\right)} \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}} \]
    8. associate-/r/45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\left(\color{blue}{\frac{a}{\frac{\pi}{b}}} \cdot a\right) \cdot \left(\frac{a}{\pi} \cdot \left(a \cdot b\right)\right)}} \]
    9. *-commutative45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\left(\frac{a}{\frac{\pi}{b}} \cdot a\right) \cdot \left(\frac{a}{\pi} \cdot \color{blue}{\left(b \cdot a\right)}\right)}} \]
    10. associate-*r*45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\left(\frac{a}{\frac{\pi}{b}} \cdot a\right) \cdot \color{blue}{\left(\left(\frac{a}{\pi} \cdot b\right) \cdot a\right)}}} \]
    11. associate-/r/45.5%

      \[\leadsto \sqrt{\frac{0.5 \cdot 0.5}{\left(\frac{a}{\frac{\pi}{b}} \cdot a\right) \cdot \left(\color{blue}{\frac{a}{\frac{\pi}{b}}} \cdot a\right)}} \]
    12. frac-times45.5%

      \[\leadsto \sqrt{\color{blue}{\frac{0.5}{\frac{a}{\frac{\pi}{b}} \cdot a} \cdot \frac{0.5}{\frac{a}{\frac{\pi}{b}} \cdot a}}} \]
    13. associate-/l/45.5%

      \[\leadsto \sqrt{\color{blue}{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}} \cdot \frac{0.5}{\frac{a}{\frac{\pi}{b}} \cdot a}} \]
    14. associate-/l/45.5%

      \[\leadsto \sqrt{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}} \cdot \color{blue}{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}}} \]
  11. Applied egg-rr35.3%

    \[\leadsto \color{blue}{\frac{-0.5}{a} \cdot \frac{\frac{\pi}{b}}{a}} \]
  12. Final simplification35.3%

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

Alternative 8: 64.2% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5}{a} \cdot \frac{\pi}{a \cdot b} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (* (/ 0.5 a) (/ PI (* a b))))
assert(a < b);
double code(double a, double b) {
	return (0.5 / a) * (((double) M_PI) / (a * b));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 / a) * (Math.PI / (a * b));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 / a) * (math.pi / (a * b))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 / a) * Float64(pi / Float64(a * b)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 / a) * (pi / (a * b));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5}{a} \cdot \frac{\pi}{a \cdot b}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative75.8%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*75.8%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\frac{b \cdot b - a \cdot a}{1}}} \]
    5. /-rgt-identity75.8%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}}{\color{blue}{b \cdot b - a \cdot a}} \]
    6. associate-/l*75.8%

      \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{\frac{b \cdot b - a \cdot a}{\frac{\pi}{2}}}} \]
    7. difference-of-squares86.7%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\frac{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}}{\frac{\pi}{2}}} \]
    8. associate-/l*86.8%

      \[\leadsto \frac{\frac{1}{a} - \frac{1}{b}}{\color{blue}{\frac{b + a}{\frac{\frac{\pi}{2}}{b - a}}}} \]
    9. associate-/l*99.5%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    10. associate-*r/88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
    11. sub-neg88.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    12. distribute-neg-frac88.2%

      \[\leadsto \left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
    13. metadata-eval88.2%

      \[\leadsto \left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  3. Simplified88.2%

    \[\leadsto \color{blue}{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a}} \]
  4. Taylor expanded in a around 0 64.5%

    \[\leadsto \color{blue}{\frac{1}{a}} \cdot \frac{\frac{\frac{\pi}{2}}{b - a}}{b + a} \]
  5. Taylor expanded in b around inf 92.6%

    \[\leadsto \frac{1}{a} \cdot \frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{b + a} \]
  6. Step-by-step derivation
    1. expm1-log1p-u72.7%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)\right)} \]
    2. expm1-udef53.6%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{1}{a} \cdot \frac{0.5 \cdot \frac{\pi}{b}}{b + a}\right)} - 1} \]
    3. frac-times53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{1 \cdot \left(0.5 \cdot \frac{\pi}{b}\right)}{a \cdot \left(b + a\right)}}\right)} - 1 \]
    4. *-un-lft-identity53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\frac{\color{blue}{0.5 \cdot \frac{\pi}{b}}}{a \cdot \left(b + a\right)}\right)} - 1 \]
    5. times-frac53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{b + a}}\right)} - 1 \]
    6. +-commutative53.6%

      \[\leadsto e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{a + b}}\right)} - 1 \]
  7. Applied egg-rr53.6%

    \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)} - 1} \]
  8. Step-by-step derivation
    1. expm1-def72.7%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\right)\right)} \]
    2. expm1-log1p92.6%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}} \]
    3. associate-/l/91.8%

      \[\leadsto \frac{0.5}{a} \cdot \color{blue}{\frac{\pi}{\left(a + b\right) \cdot b}} \]
  9. Simplified91.8%

    \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{\left(a + b\right) \cdot b}} \]
  10. Taylor expanded in a around inf 61.5%

    \[\leadsto \frac{0.5}{a} \cdot \color{blue}{\frac{\pi}{a \cdot b}} \]
  11. Final simplification61.5%

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

Alternative 9: 64.2% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (/ 0.5 a) (/ a (/ PI b))))
assert(a < b);
double code(double a, double b) {
	return (0.5 / a) / (a / (((double) M_PI) / b));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 / a) / (a / (Math.PI / b));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 / a) / (a / (math.pi / b))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 / a) / Float64(a / Float64(pi / b)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 / a) / (a / (pi / b));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 / a), $MachinePrecision] / N[(a / N[(Pi / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity75.8%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. associate-*l/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
    4. difference-of-squares86.7%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    5. *-commutative86.7%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
    7. sub-neg99.5%

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

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

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
  4. Taylor expanded in a around inf 66.3%

    \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \color{blue}{\frac{-1}{a \cdot b}} \]
  5. Taylor expanded in b around 0 61.5%

    \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{\pi}{a}\right)} \cdot \frac{-1}{a \cdot b} \]
  6. Step-by-step derivation
    1. associate-*r/61.5%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  7. Simplified61.5%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  8. Step-by-step derivation
    1. associate-/l*61.5%

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

      \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \color{blue}{\frac{\frac{-1}{a}}{b}} \]
    3. frac-times61.5%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
  9. Applied egg-rr61.5%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
  10. Step-by-step derivation
    1. associate-*r/61.5%

      \[\leadsto \frac{\color{blue}{\frac{-0.5 \cdot -1}{a}}}{\frac{a}{\pi} \cdot b} \]
    2. metadata-eval61.5%

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

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

      \[\leadsto \frac{\frac{0.5}{a}}{\color{blue}{\frac{a}{\frac{\pi}{b}}}} \]
  11. Simplified61.5%

    \[\leadsto \color{blue}{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}} \]
  12. Final simplification61.5%

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

Alternative 10: 64.2% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\frac{0.5}{a}}{\frac{a \cdot b}{\pi}} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b) :precision binary64 (/ (/ 0.5 a) (/ (* a b) PI)))
assert(a < b);
double code(double a, double b) {
	return (0.5 / a) / ((a * b) / ((double) M_PI));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 / a) / ((a * b) / Math.PI);
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 / a) / ((a * b) / math.pi)
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 / a) / Float64(Float64(a * b) / pi))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 / a) / ((a * b) / pi);
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 / a), $MachinePrecision] / N[(N[(a * b), $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{\frac{0.5}{a}}{\frac{a \cdot b}{\pi}}
\end{array}
Derivation
  1. Initial program 75.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. associate-*r/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot 1}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity75.8%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. associate-*l/75.8%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{b \cdot b - a \cdot a}} \]
    4. difference-of-squares86.7%

      \[\leadsto \frac{\frac{\pi}{2} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    5. *-commutative86.7%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b + a}} \]
    7. sub-neg99.5%

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

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

      \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{\color{blue}{-1}}{b}}{b + a} \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b - a} \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{b + a}} \]
  4. Taylor expanded in a around inf 66.3%

    \[\leadsto \frac{\frac{\pi}{2}}{b - a} \cdot \color{blue}{\frac{-1}{a \cdot b}} \]
  5. Taylor expanded in b around 0 61.5%

    \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{\pi}{a}\right)} \cdot \frac{-1}{a \cdot b} \]
  6. Step-by-step derivation
    1. associate-*r/61.5%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  7. Simplified61.5%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot \pi}{a}} \cdot \frac{-1}{a \cdot b} \]
  8. Step-by-step derivation
    1. associate-/l*61.5%

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

      \[\leadsto \frac{-0.5}{\frac{a}{\pi}} \cdot \color{blue}{\frac{\frac{-1}{a}}{b}} \]
    3. frac-times61.5%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
  9. Applied egg-rr61.5%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot \frac{-1}{a}}{\frac{a}{\pi} \cdot b}} \]
  10. Step-by-step derivation
    1. associate-*r/61.5%

      \[\leadsto \frac{\color{blue}{\frac{-0.5 \cdot -1}{a}}}{\frac{a}{\pi} \cdot b} \]
    2. metadata-eval61.5%

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

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

      \[\leadsto \frac{\frac{0.5}{a}}{\color{blue}{\frac{a}{\frac{\pi}{b}}}} \]
  11. Simplified61.5%

    \[\leadsto \color{blue}{\frac{\frac{0.5}{a}}{\frac{a}{\frac{\pi}{b}}}} \]
  12. Taylor expanded in a around 0 61.5%

    \[\leadsto \frac{\frac{0.5}{a}}{\color{blue}{\frac{a \cdot b}{\pi}}} \]
  13. Final simplification61.5%

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

Reproduce

?
herbie shell --seed 2023333 
(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))))