NMSE Section 6.1 mentioned, B

Percentage Accurate: 78.2% → 99.7%
Time: 10.7s
Alternatives: 5
Speedup: 1.9×

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: 78.2% accurate, 1.0× speedup?

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

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

Alternative 1: 99.7% accurate, 1.9× speedup?

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

\\
\frac{\frac{0.5 \cdot \pi}{a \cdot b}}{a + b}
\end{array}
Derivation
  1. Initial program 74.2%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative74.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*74.2%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/74.2%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity74.2%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified74.2%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity74.2%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares82.0%

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

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
    4. add-sqr-sqrt51.3%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    5. sqrt-unprod73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    6. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    7. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    8. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    9. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    10. sqrt-unprod34.2%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    11. add-sqr-sqrt63.4%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    12. div-inv63.4%

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

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
  6. Applied egg-rr63.4%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/63.5%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
    2. associate-/l*63.5%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
    3. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
    4. *-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
    5. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
  8. Simplified63.5%

    \[\leadsto \color{blue}{\frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{a + b}} \]
  9. Taylor expanded in b around inf 99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
  10. Step-by-step derivation
    1. associate-*r/99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  11. Simplified99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  12. Step-by-step derivation
    1. *-un-lft-identity99.7%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  13. Applied egg-rr99.7%

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

Alternative 2: 96.6% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 6 \cdot 10^{+39}:\\ \;\;\;\;\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.5}{b} \cdot \frac{\frac{\pi}{a + b}}{a}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 6e+39)
   (* (/ 0.5 a) (/ (/ PI b) (+ a b)))
   (* (/ 0.5 b) (/ (/ PI (+ a b)) a))))
double code(double a, double b) {
	double tmp;
	if (b <= 6e+39) {
		tmp = (0.5 / a) * ((((double) M_PI) / b) / (a + b));
	} else {
		tmp = (0.5 / b) * ((((double) M_PI) / (a + b)) / a);
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (b <= 6e+39) {
		tmp = (0.5 / a) * ((Math.PI / b) / (a + b));
	} else {
		tmp = (0.5 / b) * ((Math.PI / (a + b)) / a);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 6e+39:
		tmp = (0.5 / a) * ((math.pi / b) / (a + b))
	else:
		tmp = (0.5 / b) * ((math.pi / (a + b)) / a)
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 6e+39)
		tmp = Float64(Float64(0.5 / a) * Float64(Float64(pi / b) / Float64(a + b)));
	else
		tmp = Float64(Float64(0.5 / b) * Float64(Float64(pi / Float64(a + b)) / a));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 6e+39)
		tmp = (0.5 / a) * ((pi / b) / (a + b));
	else
		tmp = (0.5 / b) * ((pi / (a + b)) / a);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 6e+39], N[(N[(0.5 / a), $MachinePrecision] * N[(N[(Pi / b), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 / b), $MachinePrecision] * N[(N[(Pi / N[(a + b), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 6 \cdot 10^{+39}:\\
\;\;\;\;\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 5.9999999999999999e39

    1. Initial program 79.7%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative79.7%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*79.7%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/79.7%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*79.7%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity79.7%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg79.7%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac79.7%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval79.7%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified79.7%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-un-lft-identity79.7%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares84.7%

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

        \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
      4. add-sqr-sqrt66.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      5. sqrt-unprod65.5%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      6. frac-times65.5%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      7. metadata-eval65.5%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      8. metadata-eval65.5%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      9. frac-times65.5%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      10. sqrt-unprod15.6%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      11. add-sqr-sqrt53.3%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      12. div-inv53.3%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \color{blue}{\left(\pi \cdot \frac{1}{2}\right)}}{b - a} \]
      13. metadata-eval53.3%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
    6. Applied egg-rr53.3%

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
    7. Step-by-step derivation
      1. associate-*l/53.3%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
      2. associate-/l*53.3%

        \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
      3. +-commutative53.3%

        \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
      4. *-commutative53.3%

        \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
      5. +-commutative53.3%

        \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
    8. Simplified53.3%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{a + b}} \]
    9. Taylor expanded in b around inf 99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
    10. Step-by-step derivation
      1. associate-*r/99.7%

        \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    11. Simplified99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    12. Step-by-step derivation
      1. *-un-lft-identity99.7%

        \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    13. Applied egg-rr99.7%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    14. Step-by-step derivation
      1. times-frac99.6%

        \[\leadsto \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b}}}{a + b} \]
      2. associate-/l*95.3%

        \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}} \]
    15. Applied egg-rr95.3%

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

    if 5.9999999999999999e39 < b

    1. Initial program 55.2%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative55.2%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*55.2%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/55.2%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*55.2%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity55.2%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg55.2%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac55.2%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval55.2%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified55.2%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. *-un-lft-identity55.2%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
      2. difference-of-squares72.7%

        \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      3. times-frac99.7%

        \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
      4. add-sqr-sqrt0.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      5. sqrt-unprod99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      6. frac-times99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      7. metadata-eval99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      8. metadata-eval99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      9. frac-times99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      10. sqrt-unprod99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      11. add-sqr-sqrt99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
      12. div-inv99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \color{blue}{\left(\pi \cdot \frac{1}{2}\right)}}{b - a} \]
      13. metadata-eval99.0%

        \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
    6. Applied egg-rr99.0%

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
    7. Step-by-step derivation
      1. associate-*l/99.0%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
      2. associate-/l*98.9%

        \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
      3. +-commutative98.9%

        \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
      4. *-commutative98.9%

        \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
      5. +-commutative98.9%

        \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
    8. Simplified98.9%

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

      \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
    10. Step-by-step derivation
      1. associate-*r/99.8%

        \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    11. Simplified99.8%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    12. Step-by-step derivation
      1. *-un-lft-identity99.8%

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

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    14. Step-by-step derivation
      1. associate-/l/98.9%

        \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a + b\right) \cdot \left(a \cdot b\right)}} \]
      2. associate-/r*99.7%

        \[\leadsto \color{blue}{\frac{\frac{0.5 \cdot \pi}{a + b}}{a \cdot b}} \]
      3. associate-/l*99.7%

        \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\pi}{a + b}}}{a \cdot b} \]
      4. *-commutative99.7%

        \[\leadsto \frac{0.5 \cdot \frac{\pi}{a + b}}{\color{blue}{b \cdot a}} \]
      5. times-frac99.6%

        \[\leadsto \color{blue}{\frac{0.5}{b} \cdot \frac{\frac{\pi}{a + b}}{a}} \]
    15. Applied egg-rr99.6%

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

Alternative 3: 99.6% accurate, 1.9× speedup?

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

\\
\frac{\pi}{a + b} \cdot \frac{0.5}{a \cdot b}
\end{array}
Derivation
  1. Initial program 74.2%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative74.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*74.2%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/74.2%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity74.2%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified74.2%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity74.2%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares82.0%

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

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
    4. add-sqr-sqrt51.3%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    5. sqrt-unprod73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    6. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    7. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    8. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    9. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    10. sqrt-unprod34.2%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    11. add-sqr-sqrt63.4%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    12. div-inv63.4%

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

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
  6. Applied egg-rr63.4%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/63.5%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
    2. associate-/l*63.5%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
    3. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
    4. *-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
    5. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
  8. Simplified63.5%

    \[\leadsto \color{blue}{\frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{a + b}} \]
  9. Taylor expanded in b around inf 99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
  10. Step-by-step derivation
    1. associate-*r/99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  11. Simplified99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  12. Step-by-step derivation
    1. *-un-lft-identity99.7%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  13. Applied egg-rr99.7%

    \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  14. Step-by-step derivation
    1. associate-/l/99.2%

      \[\leadsto \color{blue}{\frac{0.5 \cdot \pi}{\left(a + b\right) \cdot \left(a \cdot b\right)}} \]
    2. *-commutative99.2%

      \[\leadsto \frac{\color{blue}{\pi \cdot 0.5}}{\left(a + b\right) \cdot \left(a \cdot b\right)} \]
    3. times-frac99.7%

      \[\leadsto \color{blue}{\frac{\pi}{a + b} \cdot \frac{0.5}{a \cdot b}} \]
  15. Applied egg-rr99.7%

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

Alternative 4: 93.7% accurate, 1.9× speedup?

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

\\
\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}
\end{array}
Derivation
  1. Initial program 74.2%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative74.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*74.2%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/74.2%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity74.2%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified74.2%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity74.2%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares82.0%

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

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
    4. add-sqr-sqrt51.3%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    5. sqrt-unprod73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    6. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    7. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    8. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    9. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    10. sqrt-unprod34.2%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    11. add-sqr-sqrt63.4%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    12. div-inv63.4%

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

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
  6. Applied egg-rr63.4%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/63.5%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
    2. associate-/l*63.5%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
    3. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
    4. *-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
    5. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
  8. Simplified63.5%

    \[\leadsto \color{blue}{\frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{a + b}} \]
  9. Taylor expanded in b around inf 99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
  10. Step-by-step derivation
    1. associate-*r/99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  11. Simplified99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  12. Step-by-step derivation
    1. *-un-lft-identity99.7%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  13. Applied egg-rr99.7%

    \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  14. Step-by-step derivation
    1. times-frac99.6%

      \[\leadsto \frac{\color{blue}{\frac{0.5}{a} \cdot \frac{\pi}{b}}}{a + b} \]
    2. associate-/l*90.9%

      \[\leadsto \color{blue}{\frac{0.5}{a} \cdot \frac{\frac{\pi}{b}}{a + b}} \]
  15. Applied egg-rr90.9%

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

Alternative 5: 62.1% accurate, 2.3× speedup?

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

\\
\frac{0.5 \cdot \frac{\pi}{a}}{a \cdot b}
\end{array}
Derivation
  1. Initial program 74.2%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative74.2%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*74.2%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/74.2%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
    5. *-rgt-identity74.2%

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg74.2%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval74.2%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified74.2%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. *-un-lft-identity74.2%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares82.0%

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

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b - a}} \]
    4. add-sqr-sqrt51.3%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b}} \cdot \sqrt{\frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    5. sqrt-unprod73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{-1}{b} \cdot \frac{-1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    6. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{-1 \cdot -1}{b \cdot b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    7. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    8. metadata-eval73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\frac{\color{blue}{1 \cdot 1}}{b \cdot b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    9. frac-times73.0%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \sqrt{\color{blue}{\frac{1}{b} \cdot \frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    10. sqrt-unprod34.2%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\sqrt{\frac{1}{b}} \cdot \sqrt{\frac{1}{b}}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    11. add-sqr-sqrt63.4%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \color{blue}{\frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b - a} \]
    12. div-inv63.4%

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

      \[\leadsto \frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
  6. Applied egg-rr63.4%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
  7. Step-by-step derivation
    1. associate-*l/63.5%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \left(\pi \cdot 0.5\right)}{b - a}}{b + a}} \]
    2. associate-/l*63.5%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(\left(\frac{1}{a} + \frac{1}{b}\right) \cdot \frac{\pi \cdot 0.5}{b - a}\right)}}{b + a} \]
    3. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\color{blue}{\left(\frac{1}{b} + \frac{1}{a}\right)} \cdot \frac{\pi \cdot 0.5}{b - a}\right)}{b + a} \]
    4. *-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{\color{blue}{0.5 \cdot \pi}}{b - a}\right)}{b + a} \]
    5. +-commutative63.5%

      \[\leadsto \frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{\color{blue}{a + b}} \]
  8. Simplified63.5%

    \[\leadsto \color{blue}{\frac{1 \cdot \left(\left(\frac{1}{b} + \frac{1}{a}\right) \cdot \frac{0.5 \cdot \pi}{b - a}\right)}{a + b}} \]
  9. Taylor expanded in b around inf 99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\left(0.5 \cdot \frac{\pi}{a \cdot b}\right)}}{a + b} \]
  10. Step-by-step derivation
    1. associate-*r/99.7%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  11. Simplified99.7%

    \[\leadsto \frac{1 \cdot \color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
  12. Step-by-step derivation
    1. *-un-lft-identity99.7%

      \[\leadsto \color{blue}{1 \cdot \frac{1 \cdot \frac{0.5 \cdot \pi}{a \cdot b}}{a + b}} \]
    2. *-un-lft-identity99.7%

      \[\leadsto 1 \cdot \frac{\color{blue}{\frac{0.5 \cdot \pi}{a \cdot b}}}{a + b} \]
    3. associate-/r*99.7%

      \[\leadsto 1 \cdot \frac{\color{blue}{\frac{\frac{0.5 \cdot \pi}{a}}{b}}}{a + b} \]
  13. Applied egg-rr99.7%

    \[\leadsto \color{blue}{1 \cdot \frac{\frac{\frac{0.5 \cdot \pi}{a}}{b}}{a + b}} \]
  14. Step-by-step derivation
    1. *-lft-identity99.7%

      \[\leadsto \color{blue}{\frac{\frac{\frac{0.5 \cdot \pi}{a}}{b}}{a + b}} \]
    2. associate-/l/90.1%

      \[\leadsto \color{blue}{\frac{\frac{0.5 \cdot \pi}{a}}{\left(a + b\right) \cdot b}} \]
    3. associate-*r/90.1%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\pi}{a}}}{\left(a + b\right) \cdot b} \]
  15. Simplified90.1%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \frac{\pi}{a}}{\left(a + b\right) \cdot b}} \]
  16. Taylor expanded in a around inf 64.8%

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

Reproduce

?
herbie shell --seed 2024137 
(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))))