NMSE Section 6.1 mentioned, B

Percentage Accurate: 79.1% → 99.7%
Time: 10.8s
Alternatives: 6
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 6 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: 79.1% 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?

\[\begin{array}{l} \\ \frac{0.5 \cdot \frac{\pi}{a \cdot b}}{a + b} \end{array} \]
(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(0.5 * Float64(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[(0.5 * N[(Pi / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{0.5 \cdot \frac{\pi}{a \cdot b}}{a + b}
\end{array}
Derivation
  1. Initial program 79.5%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative79.5%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*79.5%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/79.5%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*79.5%

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

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg79.5%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified79.5%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Taylor expanded in a around 0 56.3%

    \[\leadsto \frac{\color{blue}{\frac{1}{a}} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  6. Step-by-step derivation
    1. *-un-lft-identity56.3%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\frac{1}{a} \cdot \frac{\pi}{2}\right)}}{b \cdot b - a \cdot a} \]
    2. difference-of-squares60.2%

      \[\leadsto \frac{1 \cdot \left(\frac{1}{a} \cdot \frac{\pi}{2}\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    3. times-frac65.7%

      \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{\frac{1}{a} \cdot \frac{\pi}{2}}{b - a}} \]
    4. div-inv65.7%

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

      \[\leadsto \frac{1}{b + a} \cdot \frac{\frac{1}{a} \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b - a} \]
    6. associate-*l/65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\color{blue}{\frac{1 \cdot \left(\pi \cdot 0.5\right)}{a}}}{b - a} \]
    7. *-un-lft-identity65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\frac{\color{blue}{\pi \cdot 0.5}}{a}}{b - a} \]
    8. *-commutative65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\frac{\color{blue}{0.5 \cdot \pi}}{a}}{b - a} \]
    9. *-un-lft-identity65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\frac{0.5 \cdot \pi}{\color{blue}{1 \cdot a}}}{b - a} \]
    10. times-frac65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\color{blue}{\frac{0.5}{1} \cdot \frac{\pi}{a}}}{b - a} \]
    11. metadata-eval65.7%

      \[\leadsto \frac{1}{b + a} \cdot \frac{\color{blue}{0.5} \cdot \frac{\pi}{a}}{b - a} \]
  7. Applied egg-rr65.7%

    \[\leadsto \color{blue}{\frac{1}{b + a} \cdot \frac{0.5 \cdot \frac{\pi}{a}}{b - a}} \]
  8. Step-by-step derivation
    1. associate-*l/65.7%

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{0.5 \cdot \frac{\pi}{a}}{b - a}}{b + a}} \]
    2. *-lft-identity65.7%

      \[\leadsto \frac{\color{blue}{\frac{0.5 \cdot \frac{\pi}{a}}{b - a}}}{b + a} \]
    3. associate-/l*65.7%

      \[\leadsto \frac{\color{blue}{0.5 \cdot \frac{\frac{\pi}{a}}{b - a}}}{b + a} \]
    4. +-commutative65.7%

      \[\leadsto \frac{0.5 \cdot \frac{\frac{\pi}{a}}{b - a}}{\color{blue}{a + b}} \]
  9. Simplified65.7%

    \[\leadsto \color{blue}{\frac{0.5 \cdot \frac{\frac{\pi}{a}}{b - a}}{a + b}} \]
  10. Taylor expanded in a around 0 99.7%

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

Alternative 2: 96.4% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 6.5 \cdot 10^{+67}:\\ \;\;\;\;0.5 \cdot \frac{\frac{\frac{\pi}{b}}{a + b}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-0.5}{b} \cdot \frac{\frac{\pi}{b}}{-a}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 6.5e+67)
   (* 0.5 (/ (/ (/ PI b) (+ a b)) a))
   (* (/ -0.5 b) (/ (/ PI b) (- a)))))
double code(double a, double b) {
	double tmp;
	if (b <= 6.5e+67) {
		tmp = 0.5 * (((((double) M_PI) / b) / (a + b)) / a);
	} else {
		tmp = (-0.5 / b) * ((((double) M_PI) / b) / -a);
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (b <= 6.5e+67) {
		tmp = 0.5 * (((Math.PI / b) / (a + b)) / a);
	} else {
		tmp = (-0.5 / b) * ((Math.PI / b) / -a);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 6.5e+67:
		tmp = 0.5 * (((math.pi / b) / (a + b)) / a)
	else:
		tmp = (-0.5 / b) * ((math.pi / b) / -a)
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 6.5e+67)
		tmp = Float64(0.5 * Float64(Float64(Float64(pi / b) / Float64(a + b)) / a));
	else
		tmp = Float64(Float64(-0.5 / b) * Float64(Float64(pi / b) / Float64(-a)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 6.5e+67)
		tmp = 0.5 * (((pi / b) / (a + b)) / a);
	else
		tmp = (-0.5 / b) * ((pi / b) / -a);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 6.5e+67], N[(0.5 * N[(N[(N[(Pi / b), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision], N[(N[(-0.5 / b), $MachinePrecision] * N[(N[(Pi / b), $MachinePrecision] / (-a)), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.5 \cdot 10^{+67}:\\
\;\;\;\;0.5 \cdot \frac{\frac{\frac{\pi}{b}}{a + b}}{a}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 6.4999999999999995e67

    1. Initial program 80.5%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative80.5%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*80.5%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/80.5%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*80.5%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity80.5%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg80.5%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac80.5%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval80.5%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified80.5%

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

      \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
    6. Step-by-step derivation
      1. difference-of-squares65.9%

        \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      2. times-frac75.9%

        \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    7. Applied egg-rr75.9%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    8. Taylor expanded in b around 0 99.6%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-1 \cdot a}} \]
    9. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    10. Simplified99.6%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    11. Step-by-step derivation
      1. frac-2neg99.6%

        \[\leadsto \frac{-0.5}{b + a} \cdot \color{blue}{\frac{-\frac{\pi}{b}}{-\left(-a\right)}} \]
      2. frac-times89.6%

        \[\leadsto \color{blue}{\frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\left(-a\right)\right)}} \]
      3. add-sqr-sqrt44.3%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\color{blue}{\sqrt{-a} \cdot \sqrt{-a}}\right)} \]
      4. sqrt-unprod54.3%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\color{blue}{\sqrt{\left(-a\right) \cdot \left(-a\right)}}\right)} \]
      5. sqr-neg54.3%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\sqrt{\color{blue}{a \cdot a}}\right)} \]
      6. sqrt-unprod16.1%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\color{blue}{\sqrt{a} \cdot \sqrt{a}}\right)} \]
      7. add-sqr-sqrt27.9%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \left(-\color{blue}{a}\right)} \]
      8. add-sqr-sqrt11.8%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \color{blue}{\left(\sqrt{-a} \cdot \sqrt{-a}\right)}} \]
      9. sqrt-unprod51.7%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \color{blue}{\sqrt{\left(-a\right) \cdot \left(-a\right)}}} \]
      10. sqr-neg51.7%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \sqrt{\color{blue}{a \cdot a}}} \]
      11. sqrt-unprod45.3%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \color{blue}{\left(\sqrt{a} \cdot \sqrt{a}\right)}} \]
      12. add-sqr-sqrt89.6%

        \[\leadsto \frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot \color{blue}{a}} \]
    12. Applied egg-rr89.6%

      \[\leadsto \color{blue}{\frac{-0.5 \cdot \left(-\frac{\pi}{b}\right)}{\left(b + a\right) \cdot a}} \]
    13. Step-by-step derivation
      1. distribute-rgt-neg-in89.6%

        \[\leadsto \frac{\color{blue}{--0.5 \cdot \frac{\pi}{b}}}{\left(b + a\right) \cdot a} \]
      2. distribute-frac-neg89.6%

        \[\leadsto \color{blue}{-\frac{-0.5 \cdot \frac{\pi}{b}}{\left(b + a\right) \cdot a}} \]
      3. *-commutative89.6%

        \[\leadsto -\frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{a \cdot \left(b + a\right)}} \]
      4. times-frac97.4%

        \[\leadsto -\color{blue}{\frac{-0.5}{a} \cdot \frac{\frac{\pi}{b}}{b + a}} \]
      5. associate-*l/97.4%

        \[\leadsto -\color{blue}{\frac{-0.5 \cdot \frac{\frac{\pi}{b}}{b + a}}{a}} \]
      6. associate-/l*97.5%

        \[\leadsto -\color{blue}{-0.5 \cdot \frac{\frac{\frac{\pi}{b}}{b + a}}{a}} \]
      7. distribute-lft-neg-in97.5%

        \[\leadsto \color{blue}{\left(--0.5\right) \cdot \frac{\frac{\frac{\pi}{b}}{b + a}}{a}} \]
      8. metadata-eval97.5%

        \[\leadsto \color{blue}{0.5} \cdot \frac{\frac{\frac{\pi}{b}}{b + a}}{a} \]
      9. +-commutative97.5%

        \[\leadsto 0.5 \cdot \frac{\frac{\frac{\pi}{b}}{\color{blue}{a + b}}}{a} \]
    14. Simplified97.5%

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

    if 6.4999999999999995e67 < b

    1. Initial program 74.5%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative74.5%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*74.5%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/74.4%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*74.4%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity74.4%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg74.4%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac74.4%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval74.4%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified74.4%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around inf 42.0%

      \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
    6. Step-by-step derivation
      1. difference-of-squares46.9%

        \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      2. times-frac46.9%

        \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    7. Applied egg-rr46.9%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    8. Taylor expanded in b around 0 99.7%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-1 \cdot a}} \]
    9. Step-by-step derivation
      1. neg-mul-199.7%

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

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    11. Taylor expanded in b around inf 99.7%

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

Alternative 3: 73.3% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 6.8 \cdot 10^{-77}:\\ \;\;\;\;\frac{\frac{\pi}{b}}{a} \cdot \frac{--0.5}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-0.5}{b} \cdot \frac{\frac{\pi}{b}}{-a}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 6.8e-77)
   (* (/ (/ PI b) a) (/ (- -0.5) a))
   (* (/ -0.5 b) (/ (/ PI b) (- a)))))
double code(double a, double b) {
	double tmp;
	if (b <= 6.8e-77) {
		tmp = ((((double) M_PI) / b) / a) * (-(-0.5) / a);
	} else {
		tmp = (-0.5 / b) * ((((double) M_PI) / b) / -a);
	}
	return tmp;
}
public static double code(double a, double b) {
	double tmp;
	if (b <= 6.8e-77) {
		tmp = ((Math.PI / b) / a) * (-(-0.5) / a);
	} else {
		tmp = (-0.5 / b) * ((Math.PI / b) / -a);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 6.8e-77:
		tmp = ((math.pi / b) / a) * (-(-0.5) / a)
	else:
		tmp = (-0.5 / b) * ((math.pi / b) / -a)
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 6.8e-77)
		tmp = Float64(Float64(Float64(pi / b) / a) * Float64(Float64(-(-0.5)) / a));
	else
		tmp = Float64(Float64(-0.5 / b) * Float64(Float64(pi / b) / Float64(-a)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 6.8e-77)
		tmp = ((pi / b) / a) * (-(-0.5) / a);
	else
		tmp = (-0.5 / b) * ((pi / b) / -a);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 6.8e-77], N[(N[(N[(Pi / b), $MachinePrecision] / a), $MachinePrecision] * N[((--0.5) / a), $MachinePrecision]), $MachinePrecision], N[(N[(-0.5 / b), $MachinePrecision] * N[(N[(Pi / b), $MachinePrecision] / (-a)), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.8 \cdot 10^{-77}:\\
\;\;\;\;\frac{\frac{\pi}{b}}{a} \cdot \frac{--0.5}{a}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 6.79999999999999966e-77

    1. Initial program 77.5%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative77.5%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*77.5%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/77.5%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*77.5%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity77.5%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg77.5%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac77.5%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval77.5%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified77.5%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around inf 60.5%

      \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
    6. Step-by-step derivation
      1. difference-of-squares68.0%

        \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      2. times-frac79.5%

        \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    7. Applied egg-rr79.5%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    8. Taylor expanded in b around 0 99.6%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-1 \cdot a}} \]
    9. Step-by-step derivation
      1. neg-mul-199.6%

        \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    10. Simplified99.6%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    11. Taylor expanded in b around 0 75.7%

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

    if 6.79999999999999966e-77 < b

    1. Initial program 84.8%

      \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
    2. Step-by-step derivation
      1. *-commutative84.8%

        \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
      2. associate-*r*84.8%

        \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
      3. associate-*r/84.7%

        \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
      4. associate-*r*84.7%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot 1\right)}}{b \cdot b - a \cdot a} \]
      5. *-rgt-identity84.7%

        \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
      6. sub-neg84.7%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      7. distribute-neg-frac84.7%

        \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
      8. metadata-eval84.7%

        \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. Simplified84.7%

      \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around inf 46.5%

      \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
    6. Step-by-step derivation
      1. difference-of-squares49.3%

        \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
      2. times-frac49.4%

        \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    7. Applied egg-rr49.4%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
    8. Taylor expanded in b around 0 99.7%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-1 \cdot a}} \]
    9. Step-by-step derivation
      1. neg-mul-199.7%

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

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
    11. Taylor expanded in b around inf 79.7%

      \[\leadsto \color{blue}{\frac{-0.5}{b}} \cdot \frac{\frac{\pi}{b}}{-a} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 6.8 \cdot 10^{-77}:\\ \;\;\;\;\frac{\frac{\pi}{b}}{a} \cdot \frac{--0.5}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-0.5}{b} \cdot \frac{\frac{\pi}{b}}{-a}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 99.0% accurate, 1.9× speedup?

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

\\
\frac{\pi}{\left(a + b\right) \cdot \left(a \cdot \left(b \cdot 2\right)\right)}
\end{array}
Derivation
  1. Initial program 79.5%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative79.5%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*79.5%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/79.5%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*79.5%

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

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg79.5%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified79.5%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. div-inv79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{-1 \cdot \frac{1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    2. neg-mul-179.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\left(-\frac{1}{b}\right)}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    3. sub-neg79.5%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    4. frac-sub79.5%

      \[\leadsto \frac{\color{blue}{\frac{1 \cdot b - a \cdot 1}{a \cdot b}} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    5. *-un-lft-identity79.5%

      \[\leadsto \frac{\frac{\color{blue}{b} - a \cdot 1}{a \cdot b} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    6. *-rgt-identity79.5%

      \[\leadsto \frac{\frac{b - \color{blue}{a}}{a \cdot b} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  6. Applied egg-rr79.5%

    \[\leadsto \frac{\color{blue}{\frac{b - a}{a \cdot b}} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  7. Step-by-step derivation
    1. div-inv79.5%

      \[\leadsto \frac{\color{blue}{\left(\left(b - a\right) \cdot \frac{1}{a \cdot b}\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    2. div-inv79.5%

      \[\leadsto \frac{\left(\left(b - a\right) \cdot \frac{1}{a \cdot b}\right) \cdot \color{blue}{\left(\pi \cdot \frac{1}{2}\right)}}{b \cdot b - a \cdot a} \]
    3. metadata-eval79.5%

      \[\leadsto \frac{\left(\left(b - a\right) \cdot \frac{1}{a \cdot b}\right) \cdot \left(\pi \cdot \color{blue}{0.5}\right)}{b \cdot b - a \cdot a} \]
    4. associate-*l*79.5%

      \[\leadsto \frac{\color{blue}{\left(b - a\right) \cdot \left(\frac{1}{a \cdot b} \cdot \left(\pi \cdot 0.5\right)\right)}}{b \cdot b - a \cdot a} \]
    5. difference-of-squares85.7%

      \[\leadsto \frac{\left(b - a\right) \cdot \left(\frac{1}{a \cdot b} \cdot \left(\pi \cdot 0.5\right)\right)}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    6. times-frac99.6%

      \[\leadsto \color{blue}{\frac{b - a}{b + a} \cdot \frac{\frac{1}{a \cdot b} \cdot \left(\pi \cdot 0.5\right)}{b - a}} \]
    7. metadata-eval99.6%

      \[\leadsto \frac{b - a}{b + a} \cdot \frac{\frac{1}{a \cdot b} \cdot \left(\pi \cdot \color{blue}{\frac{1}{2}}\right)}{b - a} \]
    8. div-inv99.6%

      \[\leadsto \frac{b - a}{b + a} \cdot \frac{\frac{1}{a \cdot b} \cdot \color{blue}{\frac{\pi}{2}}}{b - a} \]
    9. frac-times99.7%

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

      \[\leadsto \frac{b - a}{b + a} \cdot \frac{\frac{\color{blue}{\pi}}{\left(a \cdot b\right) \cdot 2}}{b - a} \]
    11. *-commutative99.7%

      \[\leadsto \frac{b - a}{b + a} \cdot \frac{\frac{\pi}{\color{blue}{\left(b \cdot a\right)} \cdot 2}}{b - a} \]
  8. Applied egg-rr99.7%

    \[\leadsto \color{blue}{\frac{b - a}{b + a} \cdot \frac{\frac{\pi}{\left(b \cdot a\right) \cdot 2}}{b - a}} \]
  9. Step-by-step derivation
    1. +-commutative99.7%

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

      \[\leadsto \frac{b - a}{a + b} \cdot \color{blue}{\frac{\pi}{\left(b - a\right) \cdot \left(\left(b \cdot a\right) \cdot 2\right)}} \]
    3. *-commutative99.7%

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

      \[\leadsto \frac{b - a}{a + b} \cdot \frac{\pi}{\left(b - a\right) \cdot \color{blue}{\left(\left(2 \cdot b\right) \cdot a\right)}} \]
  10. Simplified99.7%

    \[\leadsto \color{blue}{\frac{b - a}{a + b} \cdot \frac{\pi}{\left(b - a\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)}} \]
  11. Taylor expanded in b around inf 61.5%

    \[\leadsto \color{blue}{1} \cdot \frac{\pi}{\left(b - a\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
  12. Step-by-step derivation
    1. *-un-lft-identity61.5%

      \[\leadsto \color{blue}{\frac{\pi}{\left(b - a\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)}} \]
    2. sub-neg61.5%

      \[\leadsto \frac{\pi}{\color{blue}{\left(b + \left(-a\right)\right)} \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    3. add-sqr-sqrt30.0%

      \[\leadsto \frac{\pi}{\left(b + \color{blue}{\sqrt{-a} \cdot \sqrt{-a}}\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    4. sqrt-unprod76.2%

      \[\leadsto \frac{\pi}{\left(b + \color{blue}{\sqrt{\left(-a\right) \cdot \left(-a\right)}}\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    5. sqr-neg76.2%

      \[\leadsto \frac{\pi}{\left(b + \sqrt{\color{blue}{a \cdot a}}\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    6. sqrt-unprod50.9%

      \[\leadsto \frac{\pi}{\left(b + \color{blue}{\sqrt{a} \cdot \sqrt{a}}\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    7. add-sqr-sqrt99.6%

      \[\leadsto \frac{\pi}{\left(b + \color{blue}{a}\right) \cdot \left(\left(2 \cdot b\right) \cdot a\right)} \]
    8. *-commutative99.6%

      \[\leadsto \frac{\pi}{\left(b + a\right) \cdot \color{blue}{\left(a \cdot \left(2 \cdot b\right)\right)}} \]
    9. *-commutative99.6%

      \[\leadsto \frac{\pi}{\left(b + a\right) \cdot \left(a \cdot \color{blue}{\left(b \cdot 2\right)}\right)} \]
  13. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\frac{\pi}{\left(b + a\right) \cdot \left(a \cdot \left(b \cdot 2\right)\right)}} \]
  14. Final simplification99.6%

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

Alternative 5: 62.2% accurate, 2.1× speedup?

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

\\
\frac{\frac{\pi}{b}}{a} \cdot \frac{--0.5}{a}
\end{array}
Derivation
  1. Initial program 79.5%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative79.5%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*79.5%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/79.5%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*79.5%

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

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg79.5%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified79.5%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Taylor expanded in a around inf 56.6%

    \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
  6. Step-by-step derivation
    1. difference-of-squares62.9%

      \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    2. times-frac71.3%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
  7. Applied egg-rr71.3%

    \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
  8. Taylor expanded in b around 0 99.6%

    \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-1 \cdot a}} \]
  9. Step-by-step derivation
    1. neg-mul-199.6%

      \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
  10. Simplified99.6%

    \[\leadsto \frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{\color{blue}{-a}} \]
  11. Taylor expanded in b around 0 65.4%

    \[\leadsto \color{blue}{\frac{-0.5}{a}} \cdot \frac{\frac{\pi}{b}}{-a} \]
  12. Final simplification65.4%

    \[\leadsto \frac{\frac{\pi}{b}}{a} \cdot \frac{--0.5}{a} \]
  13. Add Preprocessing

Alternative 6: 62.3% accurate, 2.1× speedup?

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

\\
\frac{\pi}{a \cdot b} \cdot \frac{--0.5}{a}
\end{array}
Derivation
  1. Initial program 79.5%

    \[\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right) \]
  2. Step-by-step derivation
    1. *-commutative79.5%

      \[\leadsto \color{blue}{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right)} \]
    2. associate-*r*79.5%

      \[\leadsto \color{blue}{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot \frac{1}{b \cdot b - a \cdot a}} \]
    3. associate-*r/79.5%

      \[\leadsto \color{blue}{\frac{\left(\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \frac{\pi}{2}\right) \cdot 1}{b \cdot b - a \cdot a}} \]
    4. associate-*r*79.5%

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

      \[\leadsto \frac{\left(\frac{1}{a} - \frac{1}{b}\right) \cdot \color{blue}{\frac{\pi}{2}}}{b \cdot b - a \cdot a} \]
    6. sub-neg79.5%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{a} + \left(-\frac{1}{b}\right)\right)} \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    7. distribute-neg-frac79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \color{blue}{\frac{-1}{b}}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
    8. metadata-eval79.5%

      \[\leadsto \frac{\left(\frac{1}{a} + \frac{\color{blue}{-1}}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a} \]
  3. Simplified79.5%

    \[\leadsto \color{blue}{\frac{\left(\frac{1}{a} + \frac{-1}{b}\right) \cdot \frac{\pi}{2}}{b \cdot b - a \cdot a}} \]
  4. Add Preprocessing
  5. Taylor expanded in a around inf 56.6%

    \[\leadsto \frac{\color{blue}{-0.5 \cdot \frac{\pi}{b}}}{b \cdot b - a \cdot a} \]
  6. Step-by-step derivation
    1. difference-of-squares62.9%

      \[\leadsto \frac{-0.5 \cdot \frac{\pi}{b}}{\color{blue}{\left(b + a\right) \cdot \left(b - a\right)}} \]
    2. times-frac71.3%

      \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
  7. Applied egg-rr71.3%

    \[\leadsto \color{blue}{\frac{-0.5}{b + a} \cdot \frac{\frac{\pi}{b}}{b - a}} \]
  8. Taylor expanded in b around 0 68.1%

    \[\leadsto \color{blue}{\frac{-0.5}{a}} \cdot \frac{\frac{\pi}{b}}{b - a} \]
  9. Taylor expanded in b around 0 65.4%

    \[\leadsto \frac{-0.5}{a} \cdot \color{blue}{\left(-1 \cdot \frac{\pi}{a \cdot b}\right)} \]
  10. Step-by-step derivation
    1. associate-*r/65.4%

      \[\leadsto \frac{-0.5}{a} \cdot \color{blue}{\frac{-1 \cdot \pi}{a \cdot b}} \]
    2. mul-1-neg65.4%

      \[\leadsto \frac{-0.5}{a} \cdot \frac{\color{blue}{-\pi}}{a \cdot b} \]
  11. Simplified65.4%

    \[\leadsto \frac{-0.5}{a} \cdot \color{blue}{\frac{-\pi}{a \cdot b}} \]
  12. Final simplification65.4%

    \[\leadsto \frac{\pi}{a \cdot b} \cdot \frac{--0.5}{a} \]
  13. Add Preprocessing

Reproduce

?
herbie shell --seed 2024135 
(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))))