NMSE Section 6.1 mentioned, B

Percentage Accurate: 77.6% → 99.6%
Time: 10.0s
Alternatives: 10
Speedup: 2.4×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 10 alternatives:

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

Initial Program: 77.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 1.7× speedup?

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

\\
\frac{\pi}{b + a} \cdot \frac{\frac{0.5}{b}}{a}
\end{array}
Derivation
  1. Initial program 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\mathsf{PI}\left(\right)}{b + a} \cdot \frac{\frac{\frac{1}{2} \cdot {\left(b - a\right)}^{\color{blue}{0}}}{b}}{a} \]
    12. metadata-evalN/A

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

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

      \[\leadsto \frac{\mathsf{PI}\left(\right)}{b + a} \cdot \frac{\color{blue}{\frac{\frac{1}{2}}{b}}}{a} \]
    15. lower-/.f6499.7

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

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

Alternative 2: 99.7% accurate, 2.0× speedup?

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

\\
\frac{\frac{\pi}{b + a}}{2 \cdot \left(b \cdot a\right)}
\end{array}
Derivation
  1. Initial program 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\frac{\left(b - a\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \frac{1}{2}\right)}{\left(b \cdot b - a \cdot a\right) \cdot \left(b \cdot a\right)}} \]
  6. Applied rewrites99.7%

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

Alternative 3: 99.6% accurate, 2.0× speedup?

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

\\
\pi \cdot \frac{\frac{0.5}{b \cdot a}}{b + a}
\end{array}
Derivation
  1. Initial program 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{PI}\left(\right) \cdot \frac{\frac{\frac{1}{2}}{b - a} \cdot \frac{b - a}{b \cdot a}}{b + a}} \]
    6. lower-/.f6499.5

      \[\leadsto \pi \cdot \color{blue}{\frac{\frac{0.5}{b - a} \cdot \frac{b - a}{b \cdot a}}{b + a}} \]
  6. Applied rewrites99.6%

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

Alternative 4: 67.3% accurate, 2.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -6.5 \cdot 10^{-115}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\pi \cdot \frac{0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -6.5e-115)
   (/ (* PI 0.5) (* a (* b a)))
   (* PI (/ 0.5 (* a (* b b))))))
double code(double a, double b) {
	double tmp;
	if (a <= -6.5e-115) {
		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 (a <= -6.5e-115) {
		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 a <= -6.5e-115:
		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 (a <= -6.5e-115)
		tmp = Float64(Float64(pi * 0.5) / Float64(a * Float64(b * a)));
	else
		tmp = Float64(pi * Float64(0.5 / Float64(a * Float64(b * b))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -6.5e-115)
		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[a, -6.5e-115], N[(N[(Pi * 0.5), $MachinePrecision] / N[(a * N[(b * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(Pi * N[(0.5 / N[(a * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -6.5 \cdot 10^{-115}:\\
\;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -6.50000000000000033e-115

    1. Initial program 86.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    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-*.f6475.6

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
    5. Applied rewrites75.6%

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

    if -6.50000000000000033e-115 < a

    1. Initial program 78.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. 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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\mathsf{PI}\left(\right) \cdot \frac{\frac{\frac{1}{2}}{b - a} \cdot \frac{b - a}{b \cdot a}}{b + a}} \]
      6. lower-/.f6499.5

        \[\leadsto \pi \cdot \color{blue}{\frac{\frac{0.5}{b - a} \cdot \frac{b - a}{b \cdot a}}{b + a}} \]
    6. Applied rewrites99.6%

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

      \[\leadsto \mathsf{PI}\left(\right) \cdot \color{blue}{\frac{\frac{1}{2}}{a \cdot {b}^{2}}} \]
    8. Step-by-step derivation
      1. unpow2N/A

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{PI}\left(\right) \cdot \frac{\frac{1}{2}}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
      10. lower-*.f6463.3

        \[\leadsto \pi \cdot \frac{0.5}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
    9. Applied rewrites63.3%

      \[\leadsto \pi \cdot \color{blue}{\frac{0.5}{a \cdot \left(b \cdot b\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification67.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -6.5 \cdot 10^{-115}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\pi \cdot \frac{0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 67.3% accurate, 2.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -6.5 \cdot 10^{-115}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -6.5e-115)
   (/ (* PI 0.5) (* a (* b a)))
   (/ (* PI 0.5) (* a (* b b)))))
double code(double a, double b) {
	double tmp;
	if (a <= -6.5e-115) {
		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 (a <= -6.5e-115) {
		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 a <= -6.5e-115:
		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 (a <= -6.5e-115)
		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 (a <= -6.5e-115)
		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[a, -6.5e-115], 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}\;a \leq -6.5 \cdot 10^{-115}:\\
\;\;\;\;\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 a < -6.50000000000000033e-115

    1. Initial program 86.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    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-*.f6475.6

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
    5. Applied rewrites75.6%

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

    if -6.50000000000000033e-115 < a

    1. Initial program 78.3%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. 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-*.f6463.3

        \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
    5. Applied rewrites63.3%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(b \cdot b\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification67.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -6.5 \cdot 10^{-115}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\pi \cdot 0.5}{a \cdot \left(b \cdot b\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 99.0% accurate, 2.4× speedup?

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

\\
\frac{\pi \cdot 0.5}{\left(b + a\right) \cdot \left(b \cdot a\right)}
\end{array}
Derivation
  1. Initial program 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\mathsf{PI}\left(\right) \cdot \left(\frac{1}{2} \cdot {\left(b - a\right)}^{\color{blue}{0}}\right)}{\left(b + a\right) \cdot \left(b \cdot a\right)} \]
    13. metadata-evalN/A

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

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

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

      \[\leadsto \color{blue}{\frac{\mathsf{PI}\left(\right) \cdot \frac{1}{2}}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \]
  6. Applied rewrites98.9%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \]
  7. Final simplification98.9%

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

Alternative 7: 98.9% accurate, 2.4× speedup?

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

\\
\pi \cdot \frac{0.5}{\left(b + a\right) \cdot \left(b \cdot a\right)}
\end{array}
Derivation
  1. Initial program 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\mathsf{PI}\left(\right)}{b + a} \cdot \frac{\frac{\frac{1}{2} \cdot {\left(b - a\right)}^{\color{blue}{0}}}{b}}{a} \]
    12. metadata-evalN/A

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

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

      \[\leadsto \frac{\mathsf{PI}\left(\right)}{b + a} \cdot \frac{\color{blue}{\frac{\frac{1}{2}}{b}}}{a} \]
    15. lower-/.f6499.7

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

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\frac{\frac{0.5}{b \cdot a}}{b + a} \cdot \pi} \]
    13. lift-/.f64N/A

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

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

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

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

      \[\leadsto \frac{0.5}{\color{blue}{\left(b + a\right) \cdot \left(b \cdot a\right)}} \cdot \pi \]
  8. Applied rewrites98.8%

    \[\leadsto \color{blue}{\frac{0.5}{\left(b + a\right) \cdot \left(b \cdot a\right)} \cdot \pi} \]
  9. Final simplification98.8%

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

Alternative 8: 62.2% 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 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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-*.f6461.8

      \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
  5. Applied rewrites61.8%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
  6. Final simplification61.8%

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

Alternative 9: 62.2% 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 80.7%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  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-*.f6461.8

      \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
  5. Applied rewrites61.8%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
  6. Step-by-step derivation
    1. Applied rewrites58.8%

      \[\leadsto \pi \cdot \color{blue}{\frac{0.5}{b \cdot \left(a \cdot a\right)}} \]
    2. Step-by-step derivation
      1. Applied rewrites61.8%

        \[\leadsto \pi \cdot \frac{0.5}{\left(b \cdot a\right) \cdot \color{blue}{a}} \]
      2. Final simplification61.8%

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

      Alternative 10: 56.2% accurate, 2.6× speedup?

      \[\begin{array}{l} \\ \pi \cdot \frac{0.5}{b \cdot \left(a \cdot a\right)} \end{array} \]
      (FPCore (a b) :precision binary64 (* PI (/ 0.5 (* b (* a a)))))
      double code(double a, double b) {
      	return ((double) M_PI) * (0.5 / (b * (a * a)));
      }
      
      public static double code(double a, double b) {
      	return Math.PI * (0.5 / (b * (a * a)));
      }
      
      def code(a, b):
      	return math.pi * (0.5 / (b * (a * a)))
      
      function code(a, b)
      	return Float64(pi * Float64(0.5 / Float64(b * Float64(a * a))))
      end
      
      function tmp = code(a, b)
      	tmp = pi * (0.5 / (b * (a * a)));
      end
      
      code[a_, b_] := N[(Pi * N[(0.5 / N[(b * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \pi \cdot \frac{0.5}{b \cdot \left(a \cdot a\right)}
      \end{array}
      
      Derivation
      1. Initial program 80.7%

        \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      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-*.f6461.8

          \[\leadsto \frac{0.5 \cdot \pi}{a \cdot \color{blue}{\left(a \cdot b\right)}} \]
      5. Applied rewrites61.8%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot \left(a \cdot b\right)}} \]
      6. Step-by-step derivation
        1. Applied rewrites58.8%

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

        Reproduce

        ?
        herbie shell --seed 2024223 
        (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))))