NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.8% → 99.6%
Time: 4.5s
Alternatives: 10
Speedup: 1.8×

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}

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: 78.8% 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, 1.3× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -9 \cdot 10^{+157}:\\ \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{\left(a + b\right) \cdot \left(-a\right)} \cdot \frac{-1}{b}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= a -9e+157)
   (/ (/ (* (/ PI b) 0.5) a) a)
   (* (/ (* PI 0.5) (* (+ a b) (- a))) (/ -1.0 b))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (a <= -9e+157) {
		tmp = (((((double) M_PI) / b) * 0.5) / a) / a;
	} else {
		tmp = ((((double) M_PI) * 0.5) / ((a + b) * -a)) * (-1.0 / b);
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (a <= -9e+157) {
		tmp = (((Math.PI / b) * 0.5) / a) / a;
	} else {
		tmp = ((Math.PI * 0.5) / ((a + b) * -a)) * (-1.0 / b);
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if a <= -9e+157:
		tmp = (((math.pi / b) * 0.5) / a) / a
	else:
		tmp = ((math.pi * 0.5) / ((a + b) * -a)) * (-1.0 / b)
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (a <= -9e+157)
		tmp = Float64(Float64(Float64(Float64(pi / b) * 0.5) / a) / a);
	else
		tmp = Float64(Float64(Float64(pi * 0.5) / Float64(Float64(a + b) * Float64(-a))) * Float64(-1.0 / b));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -9e+157)
		tmp = (((pi / b) * 0.5) / a) / a;
	else
		tmp = ((pi * 0.5) / ((a + b) * -a)) * (-1.0 / 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, -9e+157], N[(N[(N[(N[(Pi / b), $MachinePrecision] * 0.5), $MachinePrecision] / a), $MachinePrecision] / a), $MachinePrecision], N[(N[(N[(Pi * 0.5), $MachinePrecision] / N[(N[(a + b), $MachinePrecision] * (-a)), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;a \leq -9 \cdot 10^{+157}:\\
\;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{\pi \cdot 0.5}{\left(a + b\right) \cdot \left(-a\right)} \cdot \frac{-1}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -8.9999999999999997e157

    1. Initial program 78.8%

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

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
    3. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
      4. lower-fma.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
      5. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
      6. lift-PI.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
      7. *-commutativeN/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      8. lower-*.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      9. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      10. lift-PI.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      11. pow2N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
      12. lift-*.f6449.4

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
    4. Applied rewrites49.4%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
    5. Taylor expanded in a around inf

      \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
    6. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
      2. lift-/.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
      3. lift-PI.f6456.6

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
    7. Applied rewrites56.6%

      \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{\color{blue}{a} \cdot a} \]
    8. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a \cdot \color{blue}{a}} \]
      2. lift-/.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{\color{blue}{a \cdot a}} \]
      3. associate-/r*N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
      4. lower-/.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
      5. lower-/.f6462.7

        \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{b}}{a}}{a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{a} \]
      7. lift-PI.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
      8. lift-/.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
      9. *-commutativeN/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      10. lower-*.f64N/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      11. lift-/.f64N/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      12. lift-PI.f6462.7

        \[\leadsto \frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a} \]
    9. Applied rewrites62.7%

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

    if -8.9999999999999997e157 < a

    1. Initial program 78.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. lift-/.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{1}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - \color{blue}{a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. lift--.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b} - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      6. mult-flip-revN/A

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{2}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      8. lift-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      9. mult-flipN/A

        \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      10. metadata-evalN/A

        \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      11. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      12. difference-of-squaresN/A

        \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      13. times-fracN/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      14. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      15. lower-/.f64N/A

        \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      16. lower-+.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      17. lower-/.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      18. lift-PI.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\pi}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      19. lower--.f6488.4

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied rewrites88.4%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \color{blue}{\frac{-1}{b}} \]
    5. Step-by-step derivation
      1. lower-/.f6464.5

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{\color{blue}{b}} \]
    6. Applied rewrites64.5%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{\color{blue}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
    8. Step-by-step derivation
      1. lower-*.f6493.8

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{-1 \cdot \color{blue}{a}}\right) \cdot \frac{-1}{b} \]
    9. Applied rewrites93.8%

      \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
    10. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{-1 \cdot a}\right)} \cdot \frac{-1}{b} \]
      2. lift-+.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b} \]
      3. lift-/.f64N/A

        \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b} \]
      4. lift-PI.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\mathsf{PI}\left(\right)}}{-1 \cdot a}\right) \cdot \frac{-1}{b} \]
      5. lift-/.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
      6. frac-timesN/A

        \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\left(b + a\right) \cdot \left(-1 \cdot a\right)}} \cdot \frac{-1}{b} \]
      7. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\left(b + a\right) \cdot \left(-1 \cdot a\right)}} \cdot \frac{-1}{b} \]
      8. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{\left(b + a\right) \cdot \left(-1 \cdot a\right)} \cdot \frac{-1}{b} \]
      9. lower-*.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{\left(b + a\right) \cdot \left(-1 \cdot a\right)} \cdot \frac{-1}{b} \]
      10. lift-PI.f64N/A

        \[\leadsto \frac{\color{blue}{\pi} \cdot \frac{1}{2}}{\left(b + a\right) \cdot \left(-1 \cdot a\right)} \cdot \frac{-1}{b} \]
      11. lower-*.f64N/A

        \[\leadsto \frac{\pi \cdot \frac{1}{2}}{\color{blue}{\left(b + a\right) \cdot \left(-1 \cdot a\right)}} \cdot \frac{-1}{b} \]
      12. +-commutativeN/A

        \[\leadsto \frac{\pi \cdot \frac{1}{2}}{\color{blue}{\left(a + b\right)} \cdot \left(-1 \cdot a\right)} \cdot \frac{-1}{b} \]
      13. lower-+.f6493.6

        \[\leadsto \frac{\pi \cdot 0.5}{\color{blue}{\left(a + b\right)} \cdot \left(-1 \cdot a\right)} \cdot \frac{-1}{b} \]
      14. lift-*.f64N/A

        \[\leadsto \frac{\pi \cdot \frac{1}{2}}{\left(a + b\right) \cdot \left(-1 \cdot \color{blue}{a}\right)} \cdot \frac{-1}{b} \]
      15. mul-1-negN/A

        \[\leadsto \frac{\pi \cdot \frac{1}{2}}{\left(a + b\right) \cdot \left(\mathsf{neg}\left(a\right)\right)} \cdot \frac{-1}{b} \]
      16. lower-neg.f6493.6

        \[\leadsto \frac{\pi \cdot 0.5}{\left(a + b\right) \cdot \left(-a\right)} \cdot \frac{-1}{b} \]
    11. Applied rewrites93.6%

      \[\leadsto \color{blue}{\frac{\pi \cdot 0.5}{\left(a + b\right) \cdot \left(-a\right)} \cdot \frac{-1}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 99.4% accurate, 1.5× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{0.5}{a + b} \cdot \left(\frac{\pi}{-a} \cdot \frac{-1}{b}\right) \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (* (/ 0.5 (+ a b)) (* (/ PI (- a)) (/ -1.0 b))))
assert(a < b);
double code(double a, double b) {
	return (0.5 / (a + b)) * ((((double) M_PI) / -a) * (-1.0 / b));
}
assert a < b;
public static double code(double a, double b) {
	return (0.5 / (a + b)) * ((Math.PI / -a) * (-1.0 / b));
}
[a, b] = sort([a, b])
def code(a, b):
	return (0.5 / (a + b)) * ((math.pi / -a) * (-1.0 / b))
a, b = sort([a, b])
function code(a, b)
	return Float64(Float64(0.5 / Float64(a + b)) * Float64(Float64(pi / Float64(-a)) * Float64(-1.0 / b)))
end
a, b = num2cell(sort([a, b])){:}
function tmp = code(a, b)
	tmp = (0.5 / (a + b)) * ((pi / -a) * (-1.0 / b));
end
NOTE: a and b should be sorted in increasing order before calling this function.
code[a_, b_] := N[(N[(0.5 / N[(a + b), $MachinePrecision]), $MachinePrecision] * N[(N[(Pi / (-a)), $MachinePrecision] * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\frac{0.5}{a + b} \cdot \left(\frac{\pi}{-a} \cdot \frac{-1}{b}\right)
\end{array}
Derivation
  1. Initial program 78.8%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. lift-/.f64N/A

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{1}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. lift-*.f64N/A

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - \color{blue}{a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. lift--.f64N/A

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. lift-*.f64N/A

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b} - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. mult-flip-revN/A

      \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    7. lift-PI.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{2}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    8. lift-/.f64N/A

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    9. mult-flipN/A

      \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    10. metadata-evalN/A

      \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    11. *-commutativeN/A

      \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    12. difference-of-squaresN/A

      \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    13. times-fracN/A

      \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    14. lower-*.f64N/A

      \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    15. lower-/.f64N/A

      \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    16. lower-+.f64N/A

      \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    17. lower-/.f64N/A

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    18. lift-PI.f64N/A

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\pi}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    19. lower--.f6488.4

      \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  3. Applied rewrites88.4%

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

    \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \color{blue}{\frac{-1}{b}} \]
  5. Step-by-step derivation
    1. lower-/.f6464.5

      \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{\color{blue}{b}} \]
  6. Applied rewrites64.5%

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

    \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{\color{blue}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
  8. Step-by-step derivation
    1. lower-*.f6493.8

      \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{-1 \cdot \color{blue}{a}}\right) \cdot \frac{-1}{b} \]
  9. Applied rewrites93.8%

    \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
  10. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b}} \]
    2. lift-*.f64N/A

      \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{-1 \cdot a}\right)} \cdot \frac{-1}{b} \]
    3. lift-+.f64N/A

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

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

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{b + a} \cdot \left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right)} \]
    6. lower-*.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{b + a} \cdot \left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right)} \]
    7. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right) \]
    8. +-commutativeN/A

      \[\leadsto \frac{\frac{1}{2}}{\color{blue}{a + b}} \cdot \left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right) \]
    9. lower-+.f64N/A

      \[\leadsto \frac{\frac{1}{2}}{\color{blue}{a + b}} \cdot \left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right) \]
    10. lower-*.f6499.6

      \[\leadsto \frac{0.5}{a + b} \cdot \color{blue}{\left(\frac{\pi}{-1 \cdot a} \cdot \frac{-1}{b}\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \frac{\frac{1}{2}}{a + b} \cdot \left(\frac{\pi}{-1 \cdot \color{blue}{a}} \cdot \frac{-1}{b}\right) \]
    12. mul-1-negN/A

      \[\leadsto \frac{\frac{1}{2}}{a + b} \cdot \left(\frac{\pi}{\mathsf{neg}\left(a\right)} \cdot \frac{-1}{b}\right) \]
    13. lower-neg.f6499.6

      \[\leadsto \frac{0.5}{a + b} \cdot \left(\frac{\pi}{-a} \cdot \frac{-1}{b}\right) \]
  11. Applied rewrites99.6%

    \[\leadsto \color{blue}{\frac{0.5}{a + b} \cdot \left(\frac{\pi}{-a} \cdot \frac{-1}{b}\right)} \]
  12. Add Preprocessing

Alternative 3: 92.3% accurate, 1.1× speedup?

\[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -2.05 \cdot 10^{+68}:\\ \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\ \mathbf{elif}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\left(\frac{0.5}{a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b}\\ \mathbf{else}:\\ \;\;\;\;\left(\frac{0.5}{b} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b}\\ \end{array} \end{array} \]
NOTE: a and b should be sorted in increasing order before calling this function.
(FPCore (a b)
 :precision binary64
 (if (<= a -2.05e+68)
   (/ (/ (* (/ PI b) 0.5) a) a)
   (if (<= a -4.5e-72)
     (* (* (/ 0.5 a) (/ PI (- b a))) (/ -1.0 b))
     (* (* (/ 0.5 b) (/ PI (* -1.0 a))) (/ -1.0 b)))))
assert(a < b);
double code(double a, double b) {
	double tmp;
	if (a <= -2.05e+68) {
		tmp = (((((double) M_PI) / b) * 0.5) / a) / a;
	} else if (a <= -4.5e-72) {
		tmp = ((0.5 / a) * (((double) M_PI) / (b - a))) * (-1.0 / b);
	} else {
		tmp = ((0.5 / b) * (((double) M_PI) / (-1.0 * a))) * (-1.0 / b);
	}
	return tmp;
}
assert a < b;
public static double code(double a, double b) {
	double tmp;
	if (a <= -2.05e+68) {
		tmp = (((Math.PI / b) * 0.5) / a) / a;
	} else if (a <= -4.5e-72) {
		tmp = ((0.5 / a) * (Math.PI / (b - a))) * (-1.0 / b);
	} else {
		tmp = ((0.5 / b) * (Math.PI / (-1.0 * a))) * (-1.0 / b);
	}
	return tmp;
}
[a, b] = sort([a, b])
def code(a, b):
	tmp = 0
	if a <= -2.05e+68:
		tmp = (((math.pi / b) * 0.5) / a) / a
	elif a <= -4.5e-72:
		tmp = ((0.5 / a) * (math.pi / (b - a))) * (-1.0 / b)
	else:
		tmp = ((0.5 / b) * (math.pi / (-1.0 * a))) * (-1.0 / b)
	return tmp
a, b = sort([a, b])
function code(a, b)
	tmp = 0.0
	if (a <= -2.05e+68)
		tmp = Float64(Float64(Float64(Float64(pi / b) * 0.5) / a) / a);
	elseif (a <= -4.5e-72)
		tmp = Float64(Float64(Float64(0.5 / a) * Float64(pi / Float64(b - a))) * Float64(-1.0 / b));
	else
		tmp = Float64(Float64(Float64(0.5 / b) * Float64(pi / Float64(-1.0 * a))) * Float64(-1.0 / b));
	end
	return tmp
end
a, b = num2cell(sort([a, b])){:}
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -2.05e+68)
		tmp = (((pi / b) * 0.5) / a) / a;
	elseif (a <= -4.5e-72)
		tmp = ((0.5 / a) * (pi / (b - a))) * (-1.0 / b);
	else
		tmp = ((0.5 / b) * (pi / (-1.0 * a))) * (-1.0 / 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, -2.05e+68], N[(N[(N[(N[(Pi / b), $MachinePrecision] * 0.5), $MachinePrecision] / a), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[a, -4.5e-72], N[(N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision], N[(N[(N[(0.5 / b), $MachinePrecision] * N[(Pi / N[(-1.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
[a, b] = \mathsf{sort}([a, b])\\
\\
\begin{array}{l}
\mathbf{if}\;a \leq -2.05 \cdot 10^{+68}:\\
\;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\

\mathbf{elif}\;a \leq -4.5 \cdot 10^{-72}:\\
\;\;\;\;\left(\frac{0.5}{a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b}\\

\mathbf{else}:\\
\;\;\;\;\left(\frac{0.5}{b} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -2.05e68

    1. Initial program 78.8%

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

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
    3. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
      4. lower-fma.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
      5. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
      6. lift-PI.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
      7. *-commutativeN/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      8. lower-*.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      9. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      10. lift-PI.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
      11. pow2N/A

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
      12. lift-*.f6449.4

        \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
    4. Applied rewrites49.4%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
    5. Taylor expanded in a around inf

      \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
    6. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
      2. lift-/.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
      3. lift-PI.f6456.6

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
    7. Applied rewrites56.6%

      \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{\color{blue}{a} \cdot a} \]
    8. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a \cdot \color{blue}{a}} \]
      2. lift-/.f64N/A

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{\color{blue}{a \cdot a}} \]
      3. associate-/r*N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
      4. lower-/.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
      5. lower-/.f6462.7

        \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{b}}{a}}{a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{a} \]
      7. lift-PI.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
      8. lift-/.f64N/A

        \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
      9. *-commutativeN/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      10. lower-*.f64N/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      11. lift-/.f64N/A

        \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
      12. lift-PI.f6462.7

        \[\leadsto \frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a} \]
    9. Applied rewrites62.7%

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

    if -2.05e68 < a < -4.5e-72

    1. Initial program 78.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. lift-/.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{1}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - \color{blue}{a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. lift--.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b} - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      6. mult-flip-revN/A

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{2}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      8. lift-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      9. mult-flipN/A

        \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      10. metadata-evalN/A

        \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      11. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      12. difference-of-squaresN/A

        \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      13. times-fracN/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      14. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      15. lower-/.f64N/A

        \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      16. lower-+.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      17. lower-/.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      18. lift-PI.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\pi}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      19. lower--.f6488.4

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied rewrites88.4%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \color{blue}{\frac{-1}{b}} \]
    5. Step-by-step derivation
      1. lower-/.f6464.5

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{\color{blue}{b}} \]
    6. Applied rewrites64.5%

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

      \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{a}} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b} \]
    8. Step-by-step derivation
      1. lower-/.f6461.4

        \[\leadsto \left(\frac{0.5}{\color{blue}{a}} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b} \]
    9. Applied rewrites61.4%

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

    if -4.5e-72 < a

    1. Initial program 78.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. lift-/.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{1}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - \color{blue}{a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. lift--.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. lift-*.f64N/A

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b} - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      6. mult-flip-revN/A

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{2}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      8. lift-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      9. mult-flipN/A

        \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      10. metadata-evalN/A

        \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      11. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      12. difference-of-squaresN/A

        \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      13. times-fracN/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      14. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      15. lower-/.f64N/A

        \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      16. lower-+.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      17. lower-/.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      18. lift-PI.f64N/A

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\pi}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      19. lower--.f6488.4

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied rewrites88.4%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \color{blue}{\frac{-1}{b}} \]
    5. Step-by-step derivation
      1. lower-/.f6464.5

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{\color{blue}{b}} \]
    6. Applied rewrites64.5%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{\color{blue}{-1 \cdot a}}\right) \cdot \frac{-1}{b} \]
    8. Step-by-step derivation
      1. lower-*.f6493.8

        \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{-1 \cdot \color{blue}{a}}\right) \cdot \frac{-1}{b} \]
    9. Applied rewrites93.8%

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

      \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b}} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b} \]
    11. Step-by-step derivation
      1. Applied rewrites63.1%

        \[\leadsto \left(\frac{0.5}{\color{blue}{b}} \cdot \frac{\pi}{-1 \cdot a}\right) \cdot \frac{-1}{b} \]
    12. Recombined 3 regimes into one program.
    13. Add Preprocessing

    Alternative 4: 92.1% accurate, 1.2× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -2.05 \cdot 10^{+68}:\\ \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\ \mathbf{elif}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\left(\frac{0.5}{a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -2.05e+68)
       (/ (/ (* (/ PI b) 0.5) a) a)
       (if (<= a -4.5e-72)
         (* (* (/ 0.5 a) (/ PI (- b a))) (/ -1.0 b))
         (* (/ 1.0 (/ (* b (* b a)) PI)) 0.5))))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -2.05e+68) {
    		tmp = (((((double) M_PI) / b) * 0.5) / a) / a;
    	} else if (a <= -4.5e-72) {
    		tmp = ((0.5 / a) * (((double) M_PI) / (b - a))) * (-1.0 / b);
    	} else {
    		tmp = (1.0 / ((b * (b * a)) / ((double) M_PI))) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -2.05e+68) {
    		tmp = (((Math.PI / b) * 0.5) / a) / a;
    	} else if (a <= -4.5e-72) {
    		tmp = ((0.5 / a) * (Math.PI / (b - a))) * (-1.0 / b);
    	} else {
    		tmp = (1.0 / ((b * (b * a)) / Math.PI)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -2.05e+68:
    		tmp = (((math.pi / b) * 0.5) / a) / a
    	elif a <= -4.5e-72:
    		tmp = ((0.5 / a) * (math.pi / (b - a))) * (-1.0 / b)
    	else:
    		tmp = (1.0 / ((b * (b * a)) / math.pi)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -2.05e+68)
    		tmp = Float64(Float64(Float64(Float64(pi / b) * 0.5) / a) / a);
    	elseif (a <= -4.5e-72)
    		tmp = Float64(Float64(Float64(0.5 / a) * Float64(pi / Float64(b - a))) * Float64(-1.0 / b));
    	else
    		tmp = Float64(Float64(1.0 / Float64(Float64(b * Float64(b * a)) / pi)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -2.05e+68)
    		tmp = (((pi / b) * 0.5) / a) / a;
    	elseif (a <= -4.5e-72)
    		tmp = ((0.5 / a) * (pi / (b - a))) * (-1.0 / b);
    	else
    		tmp = (1.0 / ((b * (b * a)) / pi)) * 0.5;
    	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, -2.05e+68], N[(N[(N[(N[(Pi / b), $MachinePrecision] * 0.5), $MachinePrecision] / a), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[a, -4.5e-72], N[(N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-1.0 / b), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 / N[(N[(b * N[(b * a), $MachinePrecision]), $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -2.05 \cdot 10^{+68}:\\
    \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\
    
    \mathbf{elif}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\left(\frac{0.5}{a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if a < -2.05e68

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
      3. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
        3. *-commutativeN/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
        4. lower-fma.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        6. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        7. *-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        8. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        9. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        10. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        11. pow2N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
        12. lift-*.f6449.4

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
      4. Applied rewrites49.4%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
      5. Taylor expanded in a around inf

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
      6. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        3. lift-PI.f6456.6

          \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
      7. Applied rewrites56.6%

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{\color{blue}{a} \cdot a} \]
      8. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a \cdot \color{blue}{a}} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{\color{blue}{a \cdot a}} \]
        3. associate-/r*N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        4. lower-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        5. lower-/.f6462.7

          \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{b}}{a}}{a} \]
        6. lift-*.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{a} \]
        7. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        8. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        9. *-commutativeN/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        10. lower-*.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        11. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        12. lift-PI.f6462.7

          \[\leadsto \frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a} \]
      9. Applied rewrites62.7%

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

      if -2.05e68 < a < -4.5e-72

      1. Initial program 78.8%

        \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \color{blue}{\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        2. lift-/.f64N/A

          \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{1}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        3. lift-*.f64N/A

          \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - \color{blue}{a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        4. lift--.f64N/A

          \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b - a \cdot a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        5. lift-*.f64N/A

          \[\leadsto \left(\frac{\pi}{2} \cdot \frac{1}{\color{blue}{b \cdot b} - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        6. mult-flip-revN/A

          \[\leadsto \color{blue}{\frac{\frac{\pi}{2}}{b \cdot b - a \cdot a}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        7. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{2}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        8. lift-/.f64N/A

          \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        9. mult-flipN/A

          \[\leadsto \frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        10. metadata-evalN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\frac{1}{2}}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        11. *-commutativeN/A

          \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}}{b \cdot b - a \cdot a} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        12. difference-of-squaresN/A

          \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        13. times-fracN/A

          \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        14. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        15. lower-/.f64N/A

          \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        16. lower-+.f64N/A

          \[\leadsto \left(\frac{\frac{1}{2}}{\color{blue}{b + a}} \cdot \frac{\mathsf{PI}\left(\right)}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        17. lower-/.f64N/A

          \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \color{blue}{\frac{\mathsf{PI}\left(\right)}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        18. lift-PI.f64N/A

          \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\color{blue}{\pi}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
        19. lower--.f6488.4

          \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{\color{blue}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. Applied rewrites88.4%

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

        \[\leadsto \left(\frac{\frac{1}{2}}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \color{blue}{\frac{-1}{b}} \]
      5. Step-by-step derivation
        1. lower-/.f6464.5

          \[\leadsto \left(\frac{0.5}{b + a} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{\color{blue}{b}} \]
      6. Applied rewrites64.5%

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

        \[\leadsto \left(\color{blue}{\frac{\frac{1}{2}}{a}} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b} \]
      8. Step-by-step derivation
        1. lower-/.f6461.4

          \[\leadsto \left(\frac{0.5}{\color{blue}{a}} \cdot \frac{\pi}{b - a}\right) \cdot \frac{-1}{b} \]
      9. Applied rewrites61.4%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

        \[\leadsto \color{blue}{\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5} \]
      5. Step-by-step derivation
        1. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        3. division-flipN/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. lift-PI.f6457.3

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      6. Applied rewrites57.3%

        \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      7. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot \frac{1}{2} \]
        2. lift-*.f64N/A

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

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot \frac{1}{2} \]
        4. lower-*.f64N/A

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot \frac{1}{2} \]
        5. lower-*.f6463.0

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5 \]
      8. Applied rewrites63.0%

        \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5 \]
    3. Recombined 3 regimes into one program.
    4. Add Preprocessing

    Alternative 5: 89.6% accurate, 1.5× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -4.5e-72)
       (/ (/ (* (/ PI b) 0.5) a) a)
       (* (/ 1.0 (/ (* b (* b a)) PI)) 0.5)))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((((double) M_PI) / b) * 0.5) / a) / a;
    	} else {
    		tmp = (1.0 / ((b * (b * a)) / ((double) M_PI))) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((Math.PI / b) * 0.5) / a) / a;
    	} else {
    		tmp = (1.0 / ((b * (b * a)) / Math.PI)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -4.5e-72:
    		tmp = (((math.pi / b) * 0.5) / a) / a
    	else:
    		tmp = (1.0 / ((b * (b * a)) / math.pi)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -4.5e-72)
    		tmp = Float64(Float64(Float64(Float64(pi / b) * 0.5) / a) / a);
    	else
    		tmp = Float64(Float64(1.0 / Float64(Float64(b * Float64(b * a)) / pi)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -4.5e-72)
    		tmp = (((pi / b) * 0.5) / a) / a;
    	else
    		tmp = (1.0 / ((b * (b * a)) / pi)) * 0.5;
    	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, -4.5e-72], N[(N[(N[(N[(Pi / b), $MachinePrecision] * 0.5), $MachinePrecision] / a), $MachinePrecision] / a), $MachinePrecision], N[(N[(1.0 / N[(N[(b * N[(b * a), $MachinePrecision]), $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.5e-72

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
      3. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
        3. *-commutativeN/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
        4. lower-fma.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        6. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        7. *-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        8. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        9. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        10. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        11. pow2N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
        12. lift-*.f6449.4

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
      4. Applied rewrites49.4%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
      5. Taylor expanded in a around inf

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
      6. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        3. lift-PI.f6456.6

          \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
      7. Applied rewrites56.6%

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{\color{blue}{a} \cdot a} \]
      8. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a \cdot \color{blue}{a}} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{\color{blue}{a \cdot a}} \]
        3. associate-/r*N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        4. lower-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        5. lower-/.f6462.7

          \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{b}}{a}}{a} \]
        6. lift-*.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{a} \]
        7. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        8. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        9. *-commutativeN/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        10. lower-*.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        11. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        12. lift-PI.f6462.7

          \[\leadsto \frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a} \]
      9. Applied rewrites62.7%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

        \[\leadsto \color{blue}{\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5} \]
      5. Step-by-step derivation
        1. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        3. division-flipN/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. lift-PI.f6457.3

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      6. Applied rewrites57.3%

        \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      7. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot \frac{1}{2} \]
        2. lift-*.f64N/A

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

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot \frac{1}{2} \]
        4. lower-*.f64N/A

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot \frac{1}{2} \]
        5. lower-*.f6463.0

          \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5 \]
      8. Applied rewrites63.0%

        \[\leadsto \frac{1}{\frac{b \cdot \left(b \cdot a\right)}{\pi}} \cdot 0.5 \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 6: 84.2% accurate, 1.8× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -4.5e-72)
       (/ (/ (* (/ PI b) 0.5) a) a)
       (* (/ (/ PI a) (* b b)) 0.5)))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((((double) M_PI) / b) * 0.5) / a) / a;
    	} else {
    		tmp = ((((double) M_PI) / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((Math.PI / b) * 0.5) / a) / a;
    	} else {
    		tmp = ((Math.PI / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -4.5e-72:
    		tmp = (((math.pi / b) * 0.5) / a) / a
    	else:
    		tmp = ((math.pi / a) / (b * b)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -4.5e-72)
    		tmp = Float64(Float64(Float64(Float64(pi / b) * 0.5) / a) / a);
    	else
    		tmp = Float64(Float64(Float64(pi / a) / Float64(b * b)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -4.5e-72)
    		tmp = (((pi / b) * 0.5) / a) / a;
    	else
    		tmp = ((pi / a) / (b * b)) * 0.5;
    	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, -4.5e-72], N[(N[(N[(N[(Pi / b), $MachinePrecision] * 0.5), $MachinePrecision] / a), $MachinePrecision] / a), $MachinePrecision], N[(N[(N[(Pi / a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.5e-72

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
      3. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
        3. *-commutativeN/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
        4. lower-fma.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        6. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        7. *-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        8. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        9. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        10. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        11. pow2N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
        12. lift-*.f6449.4

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
      4. Applied rewrites49.4%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
      5. Taylor expanded in a around inf

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
      6. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        3. lift-PI.f6456.6

          \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
      7. Applied rewrites56.6%

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{\color{blue}{a} \cdot a} \]
      8. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a \cdot \color{blue}{a}} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\pi}{b}}{\color{blue}{a \cdot a}} \]
        3. associate-/r*N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        4. lower-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{\color{blue}{a}} \]
        5. lower-/.f6462.7

          \[\leadsto \frac{\frac{0.5 \cdot \frac{\pi}{b}}{a}}{a} \]
        6. lift-*.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\pi}{b}}{a}}{a} \]
        7. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        8. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a}}{a} \]
        9. *-commutativeN/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        10. lower-*.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        11. lift-/.f64N/A

          \[\leadsto \frac{\frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2}}{a}}{a} \]
        12. lift-PI.f6462.7

          \[\leadsto \frac{\frac{\frac{\pi}{b} \cdot 0.5}{a}}{a} \]
      9. Applied rewrites62.7%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

        \[\leadsto \color{blue}{\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5} \]
      5. Step-by-step derivation
        1. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        3. division-flipN/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. lift-PI.f6457.3

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      6. Applied rewrites57.3%

        \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      7. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot \frac{1}{2} \]
        2. lift-PI.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        3. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{1}{\frac{{b}^{2} \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. *-commutativeN/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        9. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        10. division-flipN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        11. associate-/r*N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        12. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        13. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        14. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\pi}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        15. pow2N/A

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot \frac{1}{2} \]
        16. lift-*.f6457.2

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5 \]
      8. Applied rewrites57.2%

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

    Alternative 7: 78.2% accurate, 1.8× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -4.5e-72)
       (/ (* 0.5 (/ PI b)) (* a a))
       (* (/ (/ PI a) (* b b)) 0.5)))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (0.5 * (((double) M_PI) / b)) / (a * a);
    	} else {
    		tmp = ((((double) M_PI) / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (0.5 * (Math.PI / b)) / (a * a);
    	} else {
    		tmp = ((Math.PI / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -4.5e-72:
    		tmp = (0.5 * (math.pi / b)) / (a * a)
    	else:
    		tmp = ((math.pi / a) / (b * b)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -4.5e-72)
    		tmp = Float64(Float64(0.5 * Float64(pi / b)) / Float64(a * a));
    	else
    		tmp = Float64(Float64(Float64(pi / a) / Float64(b * b)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -4.5e-72)
    		tmp = (0.5 * (pi / b)) / (a * a);
    	else
    		tmp = ((pi / a) / (b * b)) * 0.5;
    	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, -4.5e-72], N[(N[(0.5 * N[(Pi / b), $MachinePrecision]), $MachinePrecision] / N[(a * a), $MachinePrecision]), $MachinePrecision], N[(N[(N[(Pi / a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.5e-72

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{{a}^{2}}} \]
      3. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \frac{\frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a} + \frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{{a}^{2}}} \]
        2. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{\color{blue}{a}}^{2}} \]
        3. *-commutativeN/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{b} \cdot \frac{1}{2} + \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}}{{a}^{2}} \]
        4. lower-fma.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{\color{blue}{a}}^{2}} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\mathsf{PI}\left(\right)}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        6. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a}\right)}{{a}^{2}} \]
        7. *-commutativeN/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        8. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        9. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\mathsf{PI}\left(\right)}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        10. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{{a}^{2}} \]
        11. pow2N/A

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, \frac{1}{2}, \frac{\pi}{a} \cdot \frac{-1}{2}\right)}{a \cdot \color{blue}{a}} \]
        12. lift-*.f6449.4

          \[\leadsto \frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot \color{blue}{a}} \]
      4. Applied rewrites49.4%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\pi}{b}, 0.5, \frac{\pi}{a} \cdot -0.5\right)}{a \cdot a}} \]
      5. Taylor expanded in a around inf

        \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{\color{blue}{a} \cdot a} \]
      6. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{b}}{a \cdot a} \]
        3. lift-PI.f6456.6

          \[\leadsto \frac{0.5 \cdot \frac{\pi}{b}}{a \cdot a} \]
      7. Applied rewrites56.6%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

        \[\leadsto \color{blue}{\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5} \]
      5. Step-by-step derivation
        1. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        3. division-flipN/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. lift-PI.f6457.3

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      6. Applied rewrites57.3%

        \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      7. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot \frac{1}{2} \]
        2. lift-PI.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        3. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{1}{\frac{{b}^{2} \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. *-commutativeN/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        9. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        10. division-flipN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        11. associate-/r*N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        12. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        13. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        14. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\pi}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        15. pow2N/A

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot \frac{1}{2} \]
        16. lift-*.f6457.2

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5 \]
      8. Applied rewrites57.2%

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

    Alternative 8: 78.2% accurate, 1.8× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -4.5e-72)
       (* (/ PI (* (* a a) b)) 0.5)
       (* (/ (/ PI a) (* b b)) 0.5)))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((double) M_PI) / ((a * a) * b)) * 0.5;
    	} else {
    		tmp = ((((double) M_PI) / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (Math.PI / ((a * a) * b)) * 0.5;
    	} else {
    		tmp = ((Math.PI / a) / (b * b)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -4.5e-72:
    		tmp = (math.pi / ((a * a) * b)) * 0.5
    	else:
    		tmp = ((math.pi / a) / (b * b)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -4.5e-72)
    		tmp = Float64(Float64(pi / Float64(Float64(a * a) * b)) * 0.5);
    	else
    		tmp = Float64(Float64(Float64(pi / a) / Float64(b * b)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -4.5e-72)
    		tmp = (pi / ((a * a) * b)) * 0.5;
    	else
    		tmp = ((pi / a) / (b * b)) * 0.5;
    	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, -4.5e-72], N[(N[(Pi / N[(N[(a * a), $MachinePrecision] * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision], N[(N[(N[(Pi / a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.5e-72

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        5. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        6. pow2N/A

          \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot \frac{1}{2} \]
        7. lift-*.f6456.7

          \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5 \]
      4. Applied rewrites56.7%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

        \[\leadsto \color{blue}{\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5} \]
      5. Step-by-step derivation
        1. lift-PI.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        3. division-flipN/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. lower-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. lift-PI.f6457.3

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      6. Applied rewrites57.3%

        \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot 0.5 \]
      7. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\pi}} \cdot \frac{1}{2} \]
        2. lift-PI.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        3. lift-/.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        4. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        5. lift-*.f64N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        6. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{\left(b \cdot b\right) \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{1}{\frac{{b}^{2} \cdot a}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        8. *-commutativeN/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        9. lower-special-/N/A

          \[\leadsto \frac{1}{\frac{a \cdot {b}^{2}}{\mathsf{PI}\left(\right)}} \cdot \frac{1}{2} \]
        10. division-flipN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        11. associate-/r*N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        12. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        13. lower-/.f64N/A

          \[\leadsto \frac{\frac{\mathsf{PI}\left(\right)}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        14. lift-PI.f64N/A

          \[\leadsto \frac{\frac{\pi}{a}}{{b}^{2}} \cdot \frac{1}{2} \]
        15. pow2N/A

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot \frac{1}{2} \]
        16. lift-*.f6457.2

          \[\leadsto \frac{\frac{\pi}{a}}{b \cdot b} \cdot 0.5 \]
      8. Applied rewrites57.2%

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

    Alternative 9: 78.1% accurate, 1.9× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \begin{array}{l} \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\ \;\;\;\;\frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5\\ \end{array} \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b)
     :precision binary64
     (if (<= a -4.5e-72)
       (* (/ PI (* (* a a) b)) 0.5)
       (* (/ PI (* (* b b) a)) 0.5)))
    assert(a < b);
    double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (((double) M_PI) / ((a * a) * b)) * 0.5;
    	} else {
    		tmp = (((double) M_PI) / ((b * b) * a)) * 0.5;
    	}
    	return tmp;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -4.5e-72) {
    		tmp = (Math.PI / ((a * a) * b)) * 0.5;
    	} else {
    		tmp = (Math.PI / ((b * b) * a)) * 0.5;
    	}
    	return tmp;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	tmp = 0
    	if a <= -4.5e-72:
    		tmp = (math.pi / ((a * a) * b)) * 0.5
    	else:
    		tmp = (math.pi / ((b * b) * a)) * 0.5
    	return tmp
    
    a, b = sort([a, b])
    function code(a, b)
    	tmp = 0.0
    	if (a <= -4.5e-72)
    		tmp = Float64(Float64(pi / Float64(Float64(a * a) * b)) * 0.5);
    	else
    		tmp = Float64(Float64(pi / Float64(Float64(b * b) * a)) * 0.5);
    	end
    	return tmp
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -4.5e-72)
    		tmp = (pi / ((a * a) * b)) * 0.5;
    	else
    		tmp = (pi / ((b * b) * a)) * 0.5;
    	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, -4.5e-72], N[(N[(Pi / N[(N[(a * a), $MachinePrecision] * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision], N[(N[(Pi / N[(N[(b * b), $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -4.5 \cdot 10^{-72}:\\
    \;\;\;\;\frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -4.5e-72

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        5. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
        6. pow2N/A

          \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot \frac{1}{2} \]
        7. lift-*.f6456.7

          \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5 \]
      4. Applied rewrites56.7%

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

      if -4.5e-72 < a

      1. Initial program 78.8%

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

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \color{blue}{\frac{1}{2}} \]
        3. lower-/.f64N/A

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        4. lift-PI.f64N/A

          \[\leadsto \frac{\pi}{a \cdot {b}^{2}} \cdot \frac{1}{2} \]
        5. *-commutativeN/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        6. lower-*.f64N/A

          \[\leadsto \frac{\pi}{{b}^{2} \cdot a} \cdot \frac{1}{2} \]
        7. pow2N/A

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot \frac{1}{2} \]
        8. lift-*.f6457.3

          \[\leadsto \frac{\pi}{\left(b \cdot b\right) \cdot a} \cdot 0.5 \]
      4. Applied rewrites57.3%

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

    Alternative 10: 56.7% accurate, 2.4× speedup?

    \[\begin{array}{l} [a, b] = \mathsf{sort}([a, b])\\ \\ \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5 \end{array} \]
    NOTE: a and b should be sorted in increasing order before calling this function.
    (FPCore (a b) :precision binary64 (* (/ PI (* (* a a) b)) 0.5))
    assert(a < b);
    double code(double a, double b) {
    	return (((double) M_PI) / ((a * a) * b)) * 0.5;
    }
    
    assert a < b;
    public static double code(double a, double b) {
    	return (Math.PI / ((a * a) * b)) * 0.5;
    }
    
    [a, b] = sort([a, b])
    def code(a, b):
    	return (math.pi / ((a * a) * b)) * 0.5
    
    a, b = sort([a, b])
    function code(a, b)
    	return Float64(Float64(pi / Float64(Float64(a * a) * b)) * 0.5)
    end
    
    a, b = num2cell(sort([a, b])){:}
    function tmp = code(a, b)
    	tmp = (pi / ((a * a) * b)) * 0.5;
    end
    
    NOTE: a and b should be sorted in increasing order before calling this function.
    code[a_, b_] := N[(N[(Pi / N[(N[(a * a), $MachinePrecision] * b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]
    
    \begin{array}{l}
    [a, b] = \mathsf{sort}([a, b])\\
    \\
    \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5
    \end{array}
    
    Derivation
    1. Initial program 78.8%

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

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b}} \]
    3. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \color{blue}{\frac{1}{2}} \]
      3. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{PI}\left(\right)}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
      4. lift-PI.f64N/A

        \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
      5. lower-*.f64N/A

        \[\leadsto \frac{\pi}{{a}^{2} \cdot b} \cdot \frac{1}{2} \]
      6. pow2N/A

        \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot \frac{1}{2} \]
      7. lift-*.f6456.7

        \[\leadsto \frac{\pi}{\left(a \cdot a\right) \cdot b} \cdot 0.5 \]
    4. Applied rewrites56.7%

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

    Reproduce

    ?
    herbie shell --seed 2025132 
    (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))))