NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.4% → 99.6%
Time: 11.2s
Alternatives: 5
Speedup: 1.1×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 5 alternatives:

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

Initial Program: 78.4% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 1.1× speedup?

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

\\
\frac{\frac{\pi}{a + b}}{2} \cdot \frac{1}{a \cdot b}
\end{array}
Derivation
  1. Initial program 78.4%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. inv-pow78.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. difference-of-squares87.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. unpow-prod-down88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. inv-pow88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. inv-pow88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  3. Applied egg-rr88.1%

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

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity88.2%

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. +-commutative88.2%

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

    \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  6. Step-by-step derivation
    1. pow188.2%

      \[\leadsto \color{blue}{{\left(\left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1}} \]
    2. frac-times88.2%

      \[\leadsto {\left(\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
    3. +-commutative88.2%

      \[\leadsto {\left(\frac{\pi \cdot \frac{1}{\color{blue}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
    4. div-inv88.3%

      \[\leadsto {\left(\frac{\color{blue}{\frac{\pi}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
    5. +-commutative88.3%

      \[\leadsto {\left(\frac{\frac{\pi}{\color{blue}{a + b}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
    6. inv-pow88.3%

      \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left(\color{blue}{{a}^{-1}} - \frac{1}{b}\right)\right)}^{1} \]
    7. inv-pow88.3%

      \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - \color{blue}{{b}^{-1}}\right)\right)}^{1} \]
  7. Applied egg-rr88.3%

    \[\leadsto \color{blue}{{\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - {b}^{-1}\right)\right)}^{1}} \]
  8. Step-by-step derivation
    1. unpow188.3%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left({a}^{-1} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)}} \]
    3. unpow-199.6%

      \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\color{blue}{\frac{1}{a}} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)} \]
    4. unpow-199.6%

      \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \color{blue}{\frac{1}{b}}\right)}{2 \cdot \left(b - a\right)} \]
  9. Simplified99.6%

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

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b}}{2} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b - a}} \]
  11. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b}}{2} \cdot \frac{\frac{1}{a} - \frac{1}{b}}{b - a}} \]
  12. Taylor expanded in a around 0 99.6%

    \[\leadsto \frac{\frac{\pi}{a + b}}{2} \cdot \color{blue}{\frac{1}{a \cdot b}} \]
  13. Final simplification99.6%

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

Alternative 2: 76.6% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 2.25 \cdot 10^{-67}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\pi}{b}}{a \cdot \left(2 \cdot \left(b - a\right)\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 2.25e-67)
   (* (/ PI a) (/ (/ 0.5 b) a))
   (/ (/ PI b) (* a (* 2.0 (- b a))))))
double code(double a, double b) {
	double tmp;
	if (b <= 2.25e-67) {
		tmp = (((double) M_PI) / a) * ((0.5 / 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 (b <= 2.25e-67) {
		tmp = (Math.PI / a) * ((0.5 / b) / a);
	} else {
		tmp = (Math.PI / b) / (a * (2.0 * (b - a)));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 2.25e-67:
		tmp = (math.pi / a) * ((0.5 / b) / a)
	else:
		tmp = (math.pi / b) / (a * (2.0 * (b - a)))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 2.25e-67)
		tmp = Float64(Float64(pi / a) * Float64(Float64(0.5 / b) / a));
	else
		tmp = Float64(Float64(pi / b) / Float64(a * Float64(2.0 * Float64(b - a))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 2.25e-67)
		tmp = (pi / a) * ((0.5 / b) / a);
	else
		tmp = (pi / b) / (a * (2.0 * (b - a)));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 2.25e-67], N[(N[(Pi / a), $MachinePrecision] * N[(N[(0.5 / b), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision], N[(N[(Pi / b), $MachinePrecision] / N[(a * N[(2.0 * N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.25 \cdot 10^{-67}:\\
\;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 2.25000000000000008e-67

    1. Initial program 79.6%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow79.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. difference-of-squares87.0%

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr88.1%

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

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity88.2%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative88.2%

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

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Step-by-step derivation
      1. pow188.2%

        \[\leadsto \color{blue}{{\left(\left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1}} \]
      2. frac-times88.2%

        \[\leadsto {\left(\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      3. +-commutative88.2%

        \[\leadsto {\left(\frac{\pi \cdot \frac{1}{\color{blue}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      4. div-inv88.2%

        \[\leadsto {\left(\frac{\color{blue}{\frac{\pi}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      5. +-commutative88.2%

        \[\leadsto {\left(\frac{\frac{\pi}{\color{blue}{a + b}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      6. inv-pow88.2%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left(\color{blue}{{a}^{-1}} - \frac{1}{b}\right)\right)}^{1} \]
      7. inv-pow88.2%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - \color{blue}{{b}^{-1}}\right)\right)}^{1} \]
    7. Applied egg-rr88.2%

      \[\leadsto \color{blue}{{\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - {b}^{-1}\right)\right)}^{1}} \]
    8. Step-by-step derivation
      1. unpow188.2%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left({a}^{-1} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)}} \]
      3. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\color{blue}{\frac{1}{a}} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)} \]
      4. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \color{blue}{\frac{1}{b}}\right)}{2 \cdot \left(b - a\right)} \]
    9. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{2 \cdot \left(b - a\right)}} \]
    10. Taylor expanded in a around inf 59.4%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    11. Step-by-step derivation
      1. associate-*r/59.4%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. *-commutative59.4%

        \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{{a}^{2} \cdot b} \]
      3. times-frac59.2%

        \[\leadsto \color{blue}{\frac{\pi}{{a}^{2}} \cdot \frac{0.5}{b}} \]
      4. unpow259.2%

        \[\leadsto \frac{\pi}{\color{blue}{a \cdot a}} \cdot \frac{0.5}{b} \]
    12. Simplified59.2%

      \[\leadsto \color{blue}{\frac{\pi}{a \cdot a} \cdot \frac{0.5}{b}} \]
    13. Step-by-step derivation
      1. associate-*l/59.2%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    14. Applied egg-rr59.2%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    15. Step-by-step derivation
      1. times-frac69.1%

        \[\leadsto \color{blue}{\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}} \]
    16. Simplified69.1%

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

    if 2.25000000000000008e-67 < b

    1. Initial program 75.1%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow75.1%

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

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow88.1%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr88.1%

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

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity88.2%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative88.2%

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

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Taylor expanded in a around 0 82.7%

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \color{blue}{\frac{1}{a}} \]
    7. Step-by-step derivation
      1. un-div-inv82.7%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}}{a}} \]
      2. frac-times82.8%

        \[\leadsto \frac{\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}}}{a} \]
      3. div-inv82.8%

        \[\leadsto \frac{\frac{\color{blue}{\frac{\pi}{a + b}}}{2 \cdot \left(b - a\right)}}{a} \]
    8. Applied egg-rr82.8%

      \[\leadsto \color{blue}{\frac{\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)}}{a}} \]
    9. Step-by-step derivation
      1. associate-/l/94.2%

        \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b}}{a \cdot \left(2 \cdot \left(b - a\right)\right)}} \]
    10. Simplified94.2%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b}}{a \cdot \left(2 \cdot \left(b - a\right)\right)}} \]
    11. Taylor expanded in a around 0 93.9%

      \[\leadsto \frac{\color{blue}{\frac{\pi}{b}}}{a \cdot \left(2 \cdot \left(b - a\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 2.25 \cdot 10^{-67}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\pi}{b}}{a \cdot \left(2 \cdot \left(b - a\right)\right)}\\ \end{array} \]

Alternative 3: 72.2% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 2.9 \cdot 10^{-24}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 2.9e-24) (* (/ PI a) (/ (/ 0.5 b) a)) (* (/ 0.5 a) (/ PI (* b b)))))
double code(double a, double b) {
	double tmp;
	if (b <= 2.9e-24) {
		tmp = (((double) M_PI) / a) * ((0.5 / b) / a);
	} else {
		tmp = (0.5 / a) * (((double) M_PI) / (b * b));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (b <= 2.9e-24) {
		tmp = (Math.PI / a) * ((0.5 / b) / a);
	} else {
		tmp = (0.5 / a) * (Math.PI / (b * b));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 2.9e-24:
		tmp = (math.pi / a) * ((0.5 / b) / a)
	else:
		tmp = (0.5 / a) * (math.pi / (b * b))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 2.9e-24)
		tmp = Float64(Float64(pi / a) * Float64(Float64(0.5 / b) / a));
	else
		tmp = Float64(Float64(0.5 / a) * Float64(pi / Float64(b * b)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 2.9e-24)
		tmp = (pi / a) * ((0.5 / b) / a);
	else
		tmp = (0.5 / a) * (pi / (b * b));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 2.9e-24], N[(N[(Pi / a), $MachinePrecision] * N[(N[(0.5 / b), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 / a), $MachinePrecision] * N[(Pi / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 2.9 \cdot 10^{-24}:\\
\;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 2.8999999999999999e-24

    1. Initial program 79.9%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow79.9%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. difference-of-squares87.2%

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr88.3%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left(\frac{1}{b + a} \cdot \frac{1}{b - a}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. Step-by-step derivation
      1. associate-*r/88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\frac{1}{\color{blue}{a + b}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. Simplified88.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Step-by-step derivation
      1. pow188.4%

        \[\leadsto \color{blue}{{\left(\left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1}} \]
      2. frac-times88.4%

        \[\leadsto {\left(\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      3. +-commutative88.4%

        \[\leadsto {\left(\frac{\pi \cdot \frac{1}{\color{blue}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      4. div-inv88.4%

        \[\leadsto {\left(\frac{\color{blue}{\frac{\pi}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      5. +-commutative88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{\color{blue}{a + b}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      6. inv-pow88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left(\color{blue}{{a}^{-1}} - \frac{1}{b}\right)\right)}^{1} \]
      7. inv-pow88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - \color{blue}{{b}^{-1}}\right)\right)}^{1} \]
    7. Applied egg-rr88.4%

      \[\leadsto \color{blue}{{\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - {b}^{-1}\right)\right)}^{1}} \]
    8. Step-by-step derivation
      1. unpow188.4%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left({a}^{-1} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)}} \]
      3. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\color{blue}{\frac{1}{a}} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)} \]
      4. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \color{blue}{\frac{1}{b}}\right)}{2 \cdot \left(b - a\right)} \]
    9. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{2 \cdot \left(b - a\right)}} \]
    10. Taylor expanded in a around inf 59.5%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    11. Step-by-step derivation
      1. associate-*r/59.5%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. *-commutative59.5%

        \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{{a}^{2} \cdot b} \]
      3. times-frac59.3%

        \[\leadsto \color{blue}{\frac{\pi}{{a}^{2}} \cdot \frac{0.5}{b}} \]
      4. unpow259.3%

        \[\leadsto \frac{\pi}{\color{blue}{a \cdot a}} \cdot \frac{0.5}{b} \]
    12. Simplified59.3%

      \[\leadsto \color{blue}{\frac{\pi}{a \cdot a} \cdot \frac{0.5}{b}} \]
    13. Step-by-step derivation
      1. associate-*l/59.3%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    14. Applied egg-rr59.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    15. Step-by-step derivation
      1. times-frac69.1%

        \[\leadsto \color{blue}{\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}} \]
    16. Simplified69.1%

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

    if 2.8999999999999999e-24 < b

    1. Initial program 74.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow74.0%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. difference-of-squares87.8%

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr87.6%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left(\frac{1}{b + a} \cdot \frac{1}{b - a}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. Step-by-step derivation
      1. associate-*r/87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\frac{1}{\color{blue}{a + b}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. Simplified87.7%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Taylor expanded in a around 0 80.8%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    7. Step-by-step derivation
      1. associate-*r/80.8%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. times-frac80.8%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{{b}^{2}}} \]
      3. unpow280.8%

        \[\leadsto \frac{0.5}{a} \cdot \frac{\pi}{\color{blue}{b \cdot b}} \]
    8. Simplified80.8%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 2.9 \cdot 10^{-24}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}\\ \end{array} \]

Alternative 4: 75.4% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 3.5 \cdot 10^{-24}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{b} \cdot \frac{\pi}{a \cdot b}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 3.5e-24) (* (/ PI a) (/ (/ 0.5 b) a)) (* (/ 0.5 b) (/ PI (* a b)))))
double code(double a, double b) {
	double tmp;
	if (b <= 3.5e-24) {
		tmp = (((double) M_PI) / a) * ((0.5 / b) / a);
	} else {
		tmp = (0.5 / b) * (((double) M_PI) / (a * b));
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (b <= 3.5e-24) {
		tmp = (Math.PI / a) * ((0.5 / b) / a);
	} else {
		tmp = (0.5 / b) * (Math.PI / (a * b));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 3.5e-24:
		tmp = (math.pi / a) * ((0.5 / b) / a)
	else:
		tmp = (0.5 / b) * (math.pi / (a * b))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 3.5e-24)
		tmp = Float64(Float64(pi / a) * Float64(Float64(0.5 / b) / a));
	else
		tmp = Float64(Float64(0.5 / b) * Float64(pi / Float64(a * b)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 3.5e-24)
		tmp = (pi / a) * ((0.5 / b) / a);
	else
		tmp = (0.5 / b) * (pi / (a * b));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 3.5e-24], N[(N[(Pi / a), $MachinePrecision] * N[(N[(0.5 / b), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 / b), $MachinePrecision] * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 3.5 \cdot 10^{-24}:\\
\;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 3.4999999999999996e-24

    1. Initial program 79.9%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow79.9%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. difference-of-squares87.2%

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow88.3%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr88.3%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left(\frac{1}{b + a} \cdot \frac{1}{b - a}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. Step-by-step derivation
      1. associate-*r/88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative88.4%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\frac{1}{\color{blue}{a + b}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. Simplified88.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Step-by-step derivation
      1. pow188.4%

        \[\leadsto \color{blue}{{\left(\left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1}} \]
      2. frac-times88.4%

        \[\leadsto {\left(\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      3. +-commutative88.4%

        \[\leadsto {\left(\frac{\pi \cdot \frac{1}{\color{blue}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      4. div-inv88.4%

        \[\leadsto {\left(\frac{\color{blue}{\frac{\pi}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      5. +-commutative88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{\color{blue}{a + b}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      6. inv-pow88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left(\color{blue}{{a}^{-1}} - \frac{1}{b}\right)\right)}^{1} \]
      7. inv-pow88.4%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - \color{blue}{{b}^{-1}}\right)\right)}^{1} \]
    7. Applied egg-rr88.4%

      \[\leadsto \color{blue}{{\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - {b}^{-1}\right)\right)}^{1}} \]
    8. Step-by-step derivation
      1. unpow188.4%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left({a}^{-1} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)}} \]
      3. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\color{blue}{\frac{1}{a}} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)} \]
      4. unpow-199.6%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \color{blue}{\frac{1}{b}}\right)}{2 \cdot \left(b - a\right)} \]
    9. Simplified99.6%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{2 \cdot \left(b - a\right)}} \]
    10. Taylor expanded in a around inf 59.5%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{{a}^{2} \cdot b}} \]
    11. Step-by-step derivation
      1. associate-*r/59.5%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{{a}^{2} \cdot b}} \]
      2. *-commutative59.5%

        \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{{a}^{2} \cdot b} \]
      3. times-frac59.3%

        \[\leadsto \color{blue}{\frac{\pi}{{a}^{2}} \cdot \frac{0.5}{b}} \]
      4. unpow259.3%

        \[\leadsto \frac{\pi}{\color{blue}{a \cdot a}} \cdot \frac{0.5}{b} \]
    12. Simplified59.3%

      \[\leadsto \color{blue}{\frac{\pi}{a \cdot a} \cdot \frac{0.5}{b}} \]
    13. Step-by-step derivation
      1. associate-*l/59.3%

        \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    14. Applied egg-rr59.3%

      \[\leadsto \color{blue}{\frac{\pi \cdot \frac{0.5}{b}}{a \cdot a}} \]
    15. Step-by-step derivation
      1. times-frac69.1%

        \[\leadsto \color{blue}{\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}} \]
    16. Simplified69.1%

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

    if 3.4999999999999996e-24 < b

    1. Initial program 74.0%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. inv-pow74.0%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. difference-of-squares87.8%

        \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. unpow-prod-down87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      4. inv-pow87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      5. inv-pow87.6%

        \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. Applied egg-rr87.6%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left(\frac{1}{b + a} \cdot \frac{1}{b - a}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. Step-by-step derivation
      1. associate-*r/87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      2. *-rgt-identity87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
      3. +-commutative87.7%

        \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\frac{1}{\color{blue}{a + b}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. Simplified87.7%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    6. Step-by-step derivation
      1. pow187.7%

        \[\leadsto \color{blue}{{\left(\left(\frac{\pi}{2} \cdot \frac{\frac{1}{a + b}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1}} \]
      2. frac-times87.9%

        \[\leadsto {\left(\color{blue}{\frac{\pi \cdot \frac{1}{a + b}}{2 \cdot \left(b - a\right)}} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      3. +-commutative87.9%

        \[\leadsto {\left(\frac{\pi \cdot \frac{1}{\color{blue}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      4. div-inv87.9%

        \[\leadsto {\left(\frac{\color{blue}{\frac{\pi}{b + a}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      5. +-commutative87.9%

        \[\leadsto {\left(\frac{\frac{\pi}{\color{blue}{a + b}}}{2 \cdot \left(b - a\right)} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)\right)}^{1} \]
      6. inv-pow87.9%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left(\color{blue}{{a}^{-1}} - \frac{1}{b}\right)\right)}^{1} \]
      7. inv-pow87.9%

        \[\leadsto {\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - \color{blue}{{b}^{-1}}\right)\right)}^{1} \]
    7. Applied egg-rr87.9%

      \[\leadsto \color{blue}{{\left(\frac{\frac{\pi}{a + b}}{2 \cdot \left(b - a\right)} \cdot \left({a}^{-1} - {b}^{-1}\right)\right)}^{1}} \]
    8. Step-by-step derivation
      1. unpow187.9%

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

        \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left({a}^{-1} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)}} \]
      3. unpow-199.5%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\color{blue}{\frac{1}{a}} - {b}^{-1}\right)}{2 \cdot \left(b - a\right)} \]
      4. unpow-199.5%

        \[\leadsto \frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \color{blue}{\frac{1}{b}}\right)}{2 \cdot \left(b - a\right)} \]
    9. Simplified99.5%

      \[\leadsto \color{blue}{\frac{\frac{\pi}{a + b} \cdot \left(\frac{1}{a} - \frac{1}{b}\right)}{2 \cdot \left(b - a\right)}} \]
    10. Taylor expanded in a around 0 80.8%

      \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
    11. Step-by-step derivation
      1. associate-*r/80.8%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
      2. *-commutative80.8%

        \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{a \cdot {b}^{2}} \]
      3. unpow280.8%

        \[\leadsto \frac{\pi \cdot 0.5}{a \cdot \color{blue}{\left(b \cdot b\right)}} \]
      4. associate-*r*92.0%

        \[\leadsto \frac{\pi \cdot 0.5}{\color{blue}{\left(a \cdot b\right) \cdot b}} \]
      5. times-frac92.6%

        \[\leadsto \color{blue}{\frac{\pi}{a \cdot b} \cdot \frac{0.5}{b}} \]
    12. Simplified92.6%

      \[\leadsto \color{blue}{\frac{\pi}{a \cdot b} \cdot \frac{0.5}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 3.5 \cdot 10^{-24}:\\ \;\;\;\;\frac{\pi}{a} \cdot \frac{\frac{0.5}{b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{b} \cdot \frac{\pi}{a \cdot b}\\ \end{array} \]

Alternative 5: 56.6% accurate, 1.1× speedup?

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

\\
\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}
\end{array}
Derivation
  1. Initial program 78.4%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. inv-pow78.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{{\left(b \cdot b - a \cdot a\right)}^{-1}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. difference-of-squares87.4%

      \[\leadsto \left(\frac{\pi}{2} \cdot {\color{blue}{\left(\left(b + a\right) \cdot \left(b - a\right)\right)}}^{-1}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. unpow-prod-down88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\left({\left(b + a\right)}^{-1} \cdot {\left(b - a\right)}^{-1}\right)}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    4. inv-pow88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \left(\color{blue}{\frac{1}{b + a}} \cdot {\left(b - a\right)}^{-1}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    5. inv-pow88.1%

      \[\leadsto \left(\frac{\pi}{2} \cdot \left(\frac{1}{b + a} \cdot \color{blue}{\frac{1}{b - a}}\right)\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  3. Applied egg-rr88.1%

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

      \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{b + a} \cdot 1}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. *-rgt-identity88.2%

      \[\leadsto \left(\frac{\pi}{2} \cdot \frac{\color{blue}{\frac{1}{b + a}}}{b - a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    3. +-commutative88.2%

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

    \[\leadsto \left(\frac{\pi}{2} \cdot \color{blue}{\frac{\frac{1}{a + b}}{b - a}}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  6. Taylor expanded in a around 0 59.3%

    \[\leadsto \color{blue}{0.5 \cdot \frac{\pi}{a \cdot {b}^{2}}} \]
  7. Step-by-step derivation
    1. associate-*r/59.3%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{a \cdot {b}^{2}}} \]
    2. times-frac59.3%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{{b}^{2}}} \]
    3. unpow259.3%

      \[\leadsto \frac{0.5}{a} \cdot \frac{\pi}{\color{blue}{b \cdot b}} \]
  8. Simplified59.3%

    \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b \cdot b}} \]
  9. Final simplification59.3%

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

Reproduce

?
herbie shell --seed 2023279 
(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))))