NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.4% → 99.7%
Time: 11.2s
Alternatives: 9
Speedup: 2.0×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 9 alternatives:

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

Initial Program: 78.4% accurate, 1.0× speedup?

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

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

Alternative 1: 99.7% accurate, 2.0× speedup?

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

\\
\frac{\frac{\pi}{2 \cdot \left(b + a\right)}}{b \cdot a}
\end{array}
Derivation
  1. Initial program 80.5%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
  4. Applied rewrites99.6%

    \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
  5. Applied rewrites99.7%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{2 \cdot \left(b + a\right)}}{b \cdot a}} \]
  6. Add Preprocessing

Alternative 2: 96.4% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -2 \cdot 10^{+151}:\\ \;\;\;\;\frac{\frac{\pi}{a}}{2 \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -2e+151)
   (/ (/ PI a) (* 2.0 (* b a)))
   (/ PI (* b (* a (* 2.0 (+ b a)))))))
double code(double a, double b) {
	double tmp;
	if (a <= -2e+151) {
		tmp = (((double) M_PI) / a) / (2.0 * (b * a));
	} else {
		tmp = ((double) M_PI) / (b * (a * (2.0 * (b + a))));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -2e+151) {
		tmp = (Math.PI / a) / (2.0 * (b * a));
	} else {
		tmp = Math.PI / (b * (a * (2.0 * (b + a))));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -2e+151:
		tmp = (math.pi / a) / (2.0 * (b * a))
	else:
		tmp = math.pi / (b * (a * (2.0 * (b + a))))
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -2e+151)
		tmp = Float64(Float64(pi / a) / Float64(2.0 * Float64(b * a)));
	else
		tmp = Float64(pi / Float64(b * Float64(a * Float64(2.0 * Float64(b + a)))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -2e+151)
		tmp = (pi / a) / (2.0 * (b * a));
	else
		tmp = pi / (b * (a * (2.0 * (b + a))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -2e+151], N[(N[(Pi / a), $MachinePrecision] / N[(2.0 * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(Pi / N[(b * N[(a * N[(2.0 * N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -2 \cdot 10^{+151}:\\
\;\;\;\;\frac{\frac{\pi}{a}}{2 \cdot \left(b \cdot a\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -2.00000000000000003e151

    1. Initial program 54.6%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\frac{\left(\mathsf{PI}\left(\right) \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(1 \cdot b - a \cdot 1\right)}{2 \cdot \left(a \cdot b\right)}} \]
    4. Applied rewrites78.8%

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

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

        \[\leadsto \frac{\color{blue}{\frac{\mathsf{PI}\left(\right)}{a}}}{2 \cdot \left(b \cdot a\right)} \]
      2. lower-PI.f6499.9

        \[\leadsto \frac{\frac{\color{blue}{\pi}}{a}}{2 \cdot \left(b \cdot a\right)} \]
    7. Applied rewrites99.9%

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

    if -2.00000000000000003e151 < a

    1. Initial program 84.3%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
    4. Applied rewrites99.6%

      \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
    5. Applied rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{\mathsf{PI}\left(\right)}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
      12. lower-*.f6496.8

        \[\leadsto \frac{\pi}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)} \cdot b} \]
    7. Applied rewrites96.8%

      \[\leadsto \color{blue}{\frac{\pi}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -2 \cdot 10^{+151}:\\ \;\;\;\;\frac{\frac{\pi}{a}}{2 \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 96.4% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -5.6 \cdot 10^{+151}:\\ \;\;\;\;\frac{\pi \cdot \frac{0.5}{a}}{b \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -5.6e+151)
   (/ (* PI (/ 0.5 a)) (* b a))
   (/ PI (* b (* a (* 2.0 (+ b a)))))))
double code(double a, double b) {
	double tmp;
	if (a <= -5.6e+151) {
		tmp = (((double) M_PI) * (0.5 / a)) / (b * a);
	} else {
		tmp = ((double) M_PI) / (b * (a * (2.0 * (b + a))));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (a <= -5.6e+151) {
		tmp = (Math.PI * (0.5 / a)) / (b * a);
	} else {
		tmp = Math.PI / (b * (a * (2.0 * (b + a))));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -5.6e+151:
		tmp = (math.pi * (0.5 / a)) / (b * a)
	else:
		tmp = math.pi / (b * (a * (2.0 * (b + a))))
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -5.6e+151)
		tmp = Float64(Float64(pi * Float64(0.5 / a)) / Float64(b * a));
	else
		tmp = Float64(pi / Float64(b * Float64(a * Float64(2.0 * Float64(b + a)))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -5.6e+151)
		tmp = (pi * (0.5 / a)) / (b * a);
	else
		tmp = pi / (b * (a * (2.0 * (b + a))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -5.6e+151], N[(N[(Pi * N[(0.5 / a), $MachinePrecision]), $MachinePrecision] / N[(b * a), $MachinePrecision]), $MachinePrecision], N[(Pi / N[(b * N[(a * N[(2.0 * N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -5.6 \cdot 10^{+151}:\\
\;\;\;\;\frac{\pi \cdot \frac{0.5}{a}}{b \cdot a}\\

\mathbf{else}:\\
\;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -5.59999999999999975e151

    1. Initial program 54.6%

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

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

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

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
      5. unpow2N/A

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

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

        \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
      8. lower-*.f6498.5

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
    5. Applied rewrites98.5%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
    6. Step-by-step derivation
      1. Applied rewrites99.8%

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

      if -5.59999999999999975e151 < a

      1. Initial program 84.3%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
      4. Applied rewrites99.6%

        \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      5. Applied rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \frac{\mathsf{PI}\left(\right)}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
        12. lower-*.f6496.8

          \[\leadsto \frac{\pi}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)} \cdot b} \]
      7. Applied rewrites96.8%

        \[\leadsto \color{blue}{\frac{\pi}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
    7. Recombined 2 regimes into one program.
    8. Final simplification97.2%

      \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -5.6 \cdot 10^{+151}:\\ \;\;\;\;\frac{\pi \cdot \frac{0.5}{a}}{b \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \]
    9. Add Preprocessing

    Alternative 4: 96.2% accurate, 2.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1.45 \cdot 10^{+152}:\\ \;\;\;\;\pi \cdot \frac{0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \end{array} \]
    (FPCore (a b)
     :precision binary64
     (if (<= a -1.45e+152)
       (* PI (/ 0.5 (* a (* b a))))
       (/ PI (* b (* a (* 2.0 (+ b a)))))))
    double code(double a, double b) {
    	double tmp;
    	if (a <= -1.45e+152) {
    		tmp = ((double) M_PI) * (0.5 / (a * (b * a)));
    	} else {
    		tmp = ((double) M_PI) / (b * (a * (2.0 * (b + a))));
    	}
    	return tmp;
    }
    
    public static double code(double a, double b) {
    	double tmp;
    	if (a <= -1.45e+152) {
    		tmp = Math.PI * (0.5 / (a * (b * a)));
    	} else {
    		tmp = Math.PI / (b * (a * (2.0 * (b + a))));
    	}
    	return tmp;
    }
    
    def code(a, b):
    	tmp = 0
    	if a <= -1.45e+152:
    		tmp = math.pi * (0.5 / (a * (b * a)))
    	else:
    		tmp = math.pi / (b * (a * (2.0 * (b + a))))
    	return tmp
    
    function code(a, b)
    	tmp = 0.0
    	if (a <= -1.45e+152)
    		tmp = Float64(pi * Float64(0.5 / Float64(a * Float64(b * a))));
    	else
    		tmp = Float64(pi / Float64(b * Float64(a * Float64(2.0 * Float64(b + a)))));
    	end
    	return tmp
    end
    
    function tmp_2 = code(a, b)
    	tmp = 0.0;
    	if (a <= -1.45e+152)
    		tmp = pi * (0.5 / (a * (b * a)));
    	else
    		tmp = pi / (b * (a * (2.0 * (b + a))));
    	end
    	tmp_2 = tmp;
    end
    
    code[a_, b_] := If[LessEqual[a, -1.45e+152], N[(Pi * N[(0.5 / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(Pi / N[(b * N[(a * N[(2.0 * N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;a \leq -1.45 \cdot 10^{+152}:\\
    \;\;\;\;\pi \cdot \frac{0.5}{a \cdot \left(b \cdot a\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if a < -1.4499999999999999e152

      1. Initial program 54.6%

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

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

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

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
        5. unpow2N/A

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
        8. lower-*.f6498.5

          \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
      5. Applied rewrites98.5%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
      6. Step-by-step derivation
        1. Applied rewrites98.5%

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

        if -1.4499999999999999e152 < a

        1. Initial program 84.3%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
        4. Applied rewrites99.6%

          \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
        5. Applied rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \frac{\mathsf{PI}\left(\right)}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
          12. lower-*.f6496.8

            \[\leadsto \frac{\pi}{\color{blue}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)} \cdot b} \]
        7. Applied rewrites96.8%

          \[\leadsto \color{blue}{\frac{\pi}{\left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right) \cdot b}} \]
      7. Recombined 2 regimes into one program.
      8. Final simplification97.0%

        \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.45 \cdot 10^{+152}:\\ \;\;\;\;\pi \cdot \frac{0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi}{b \cdot \left(a \cdot \left(2 \cdot \left(b + a\right)\right)\right)}\\ \end{array} \]
      9. Add Preprocessing

      Alternative 5: 96.2% accurate, 2.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -5 \cdot 10^{+113}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\pi \cdot \frac{0.5}{b \cdot \left(a \cdot \left(b + a\right)\right)}\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (if (<= a -5e+113)
         (/ (* PI 0.5) (* a (* b a)))
         (* PI (/ 0.5 (* b (* a (+ b a)))))))
      double code(double a, double b) {
      	double tmp;
      	if (a <= -5e+113) {
      		tmp = (((double) M_PI) * 0.5) / (a * (b * a));
      	} else {
      		tmp = ((double) M_PI) * (0.5 / (b * (a * (b + a))));
      	}
      	return tmp;
      }
      
      public static double code(double a, double b) {
      	double tmp;
      	if (a <= -5e+113) {
      		tmp = (Math.PI * 0.5) / (a * (b * a));
      	} else {
      		tmp = Math.PI * (0.5 / (b * (a * (b + a))));
      	}
      	return tmp;
      }
      
      def code(a, b):
      	tmp = 0
      	if a <= -5e+113:
      		tmp = (math.pi * 0.5) / (a * (b * a))
      	else:
      		tmp = math.pi * (0.5 / (b * (a * (b + a))))
      	return tmp
      
      function code(a, b)
      	tmp = 0.0
      	if (a <= -5e+113)
      		tmp = Float64(Float64(pi * 0.5) / Float64(a * Float64(b * a)));
      	else
      		tmp = Float64(pi * Float64(0.5 / Float64(b * Float64(a * Float64(b + a)))));
      	end
      	return tmp
      end
      
      function tmp_2 = code(a, b)
      	tmp = 0.0;
      	if (a <= -5e+113)
      		tmp = (pi * 0.5) / (a * (b * a));
      	else
      		tmp = pi * (0.5 / (b * (a * (b + a))));
      	end
      	tmp_2 = tmp;
      end
      
      code[a_, b_] := If[LessEqual[a, -5e+113], N[(N[(Pi * 0.5), $MachinePrecision] / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(Pi * N[(0.5 / N[(b * N[(a * N[(b + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;a \leq -5 \cdot 10^{+113}:\\
      \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\
      
      \mathbf{else}:\\
      \;\;\;\;\pi \cdot \frac{0.5}{b \cdot \left(a \cdot \left(b + a\right)\right)}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if a < -5e113

        1. Initial program 62.5%

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

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

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

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
          5. unpow2N/A

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
          8. lower-*.f6498.7

            \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
        5. Applied rewrites98.7%

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

        if -5e113 < a

        1. Initial program 83.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
        4. Applied rewrites99.6%

          \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
        5. Applied rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \left(\pi \cdot 0.5\right) \cdot \frac{1}{\color{blue}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \]
        7. Applied rewrites99.2%

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \cdot \mathsf{PI}\left(\right) \]
          8. lower-/.f6499.2

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \frac{\frac{1}{2}}{b \cdot \color{blue}{\left(a \cdot \left(b + a\right)\right)}} \cdot \mathsf{PI}\left(\right) \]
          20. lift-+.f6496.6

            \[\leadsto \frac{0.5}{b \cdot \left(a \cdot \color{blue}{\left(b + a\right)}\right)} \cdot \pi \]
        9. Applied rewrites96.6%

          \[\leadsto \color{blue}{\frac{0.5}{b \cdot \left(a \cdot \left(b + a\right)\right)} \cdot \pi} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification96.9%

        \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -5 \cdot 10^{+113}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\pi \cdot \frac{0.5}{b \cdot \left(a \cdot \left(b + a\right)\right)}\\ \end{array} \]
      5. Add Preprocessing

      Alternative 6: 99.0% accurate, 2.0× speedup?

      \[\begin{array}{l} \\ \frac{1}{\left(b + a\right) \cdot \left(b \cdot a\right)} \cdot \left(\pi \cdot 0.5\right) \end{array} \]
      (FPCore (a b) :precision binary64 (* (/ 1.0 (* (+ b a) (* b a))) (* PI 0.5)))
      double code(double a, double b) {
      	return (1.0 / ((b + a) * (b * a))) * (((double) M_PI) * 0.5);
      }
      
      public static double code(double a, double b) {
      	return (1.0 / ((b + a) * (b * a))) * (Math.PI * 0.5);
      }
      
      def code(a, b):
      	return (1.0 / ((b + a) * (b * a))) * (math.pi * 0.5)
      
      function code(a, b)
      	return Float64(Float64(1.0 / Float64(Float64(b + a) * Float64(b * a))) * Float64(pi * 0.5))
      end
      
      function tmp = code(a, b)
      	tmp = (1.0 / ((b + a) * (b * a))) * (pi * 0.5);
      end
      
      code[a_, b_] := N[(N[(1.0 / N[(N[(b + a), $MachinePrecision] * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(Pi * 0.5), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{1}{\left(b + a\right) \cdot \left(b \cdot a\right)} \cdot \left(\pi \cdot 0.5\right)
      \end{array}
      
      Derivation
      1. Initial program 80.5%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \color{blue}{\frac{\frac{1}{a} - \frac{1}{b}}{1 \cdot b - a \cdot 1} \cdot \frac{\frac{\mathsf{PI}\left(\right)}{2}}{b + a}} \]
      4. Applied rewrites99.6%

        \[\leadsto \color{blue}{\frac{\frac{b - a}{b \cdot a}}{b - a} \cdot \frac{\pi \cdot 0.5}{b + a}} \]
      5. Applied rewrites99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \left(\pi \cdot 0.5\right) \cdot \frac{1}{\color{blue}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \]
      7. Applied rewrites99.1%

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

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

      Alternative 7: 71.2% accurate, 2.2× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.1 \cdot 10^{-95}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (if (<= b 1.1e-95) (/ (* PI 0.5) (* a (* b a))) (/ (* PI 0.5) (* a (* b b)))))
      double code(double a, double b) {
      	double tmp;
      	if (b <= 1.1e-95) {
      		tmp = (((double) M_PI) * 0.5) / (a * (b * a));
      	} else {
      		tmp = (((double) M_PI) * 0.5) / (a * (b * b));
      	}
      	return tmp;
      }
      
      public static double code(double a, double b) {
      	double tmp;
      	if (b <= 1.1e-95) {
      		tmp = (Math.PI * 0.5) / (a * (b * a));
      	} else {
      		tmp = (Math.PI * 0.5) / (a * (b * b));
      	}
      	return tmp;
      }
      
      def code(a, b):
      	tmp = 0
      	if b <= 1.1e-95:
      		tmp = (math.pi * 0.5) / (a * (b * a))
      	else:
      		tmp = (math.pi * 0.5) / (a * (b * b))
      	return tmp
      
      function code(a, b)
      	tmp = 0.0
      	if (b <= 1.1e-95)
      		tmp = Float64(Float64(pi * 0.5) / Float64(a * Float64(b * a)));
      	else
      		tmp = Float64(Float64(pi * 0.5) / Float64(a * Float64(b * b)));
      	end
      	return tmp
      end
      
      function tmp_2 = code(a, b)
      	tmp = 0.0;
      	if (b <= 1.1e-95)
      		tmp = (pi * 0.5) / (a * (b * a));
      	else
      		tmp = (pi * 0.5) / (a * (b * b));
      	end
      	tmp_2 = tmp;
      end
      
      code[a_, b_] := If[LessEqual[b, 1.1e-95], N[(N[(Pi * 0.5), $MachinePrecision] / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(Pi * 0.5), $MachinePrecision] / N[(a * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;b \leq 1.1 \cdot 10^{-95}:\\
      \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\
      
      \mathbf{else}:\\
      \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot b\right)}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if b < 1.0999999999999999e-95

        1. Initial program 78.3%

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

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

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

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
          5. unpow2N/A

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
          8. lower-*.f6467.8

            \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
        5. Applied rewrites67.8%

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

        if 1.0999999999999999e-95 < b

        1. Initial program 85.9%

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

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

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

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

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

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

            \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot {b}^{2}}} \]
          6. unpow2N/A

            \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
          7. lower-*.f6472.7

            \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
        5. Applied rewrites72.7%

          \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot b\right)}} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification69.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.1 \cdot 10^{-95}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \]
      5. Add Preprocessing

      Alternative 8: 63.3% accurate, 2.6× speedup?

      \[\begin{array}{l} \\ \frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)} \end{array} \]
      (FPCore (a b) :precision binary64 (/ (* PI 0.5) (* a (* b a))))
      double code(double a, double b) {
      	return (((double) M_PI) * 0.5) / (a * (b * a));
      }
      
      public static double code(double a, double b) {
      	return (Math.PI * 0.5) / (a * (b * a));
      }
      
      def code(a, b):
      	return (math.pi * 0.5) / (a * (b * a))
      
      function code(a, b)
      	return Float64(Float64(pi * 0.5) / Float64(a * Float64(b * a)))
      end
      
      function tmp = code(a, b)
      	tmp = (pi * 0.5) / (a * (b * a));
      end
      
      code[a_, b_] := N[(N[(Pi * 0.5), $MachinePrecision] / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}
      \end{array}
      
      Derivation
      1. Initial program 80.5%

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

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

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

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
        5. unpow2N/A

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
        8. lower-*.f6464.0

          \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
      5. Applied rewrites64.0%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
      6. Final simplification64.0%

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

      Alternative 9: 63.3% accurate, 2.6× speedup?

      \[\begin{array}{l} \\ \pi \cdot \frac{0.5}{a \cdot \left(b \cdot a\right)} \end{array} \]
      (FPCore (a b) :precision binary64 (* PI (/ 0.5 (* a (* b a)))))
      double code(double a, double b) {
      	return ((double) M_PI) * (0.5 / (a * (b * a)));
      }
      
      public static double code(double a, double b) {
      	return Math.PI * (0.5 / (a * (b * a)));
      }
      
      def code(a, b):
      	return math.pi * (0.5 / (a * (b * a)))
      
      function code(a, b)
      	return Float64(pi * Float64(0.5 / Float64(a * Float64(b * a))))
      end
      
      function tmp = code(a, b)
      	tmp = pi * (0.5 / (a * (b * a)));
      end
      
      code[a_, b_] := N[(Pi * N[(0.5 / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \pi \cdot \frac{0.5}{a \cdot \left(b \cdot a\right)}
      \end{array}
      
      Derivation
      1. Initial program 80.5%

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

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

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

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \color{blue}{\mathsf{PI}\left(\right)}}{{a}^{2} \cdot b} \]
        5. unpow2N/A

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

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

          \[\leadsto \frac{\frac{1}{2} \cdot \mathsf{PI}\left(\right)}{\color{blue}{a \cdot \left(a \cdot b\right)}} \]
        8. lower-*.f6464.0

          \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
      5. Applied rewrites64.0%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
      6. Step-by-step derivation
        1. Applied rewrites63.9%

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

        Reproduce

        ?
        herbie shell --seed 2024216 
        (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))))