Quotient of sum of exps

Percentage Accurate: 99.1% → 100.0%
Time: 7.5s
Alternatives: 11
Speedup: 2.9×

Specification

?
\[\begin{array}{l} \\ \frac{e^{a}}{e^{a} + e^{b}} \end{array} \]
(FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))
double code(double a, double b) {
	return exp(a) / (exp(a) + exp(b));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = exp(a) / (exp(a) + exp(b))
end function
public static double code(double a, double b) {
	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
}
def code(a, b):
	return math.exp(a) / (math.exp(a) + math.exp(b))
function code(a, b)
	return Float64(exp(a) / Float64(exp(a) + exp(b)))
end
function tmp = code(a, b)
	tmp = exp(a) / (exp(a) + exp(b));
end
code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{e^{a}}{e^{a} + e^{b}}
\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 11 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: 99.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{e^{a}}{e^{a} + e^{b}} \end{array} \]
(FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))
double code(double a, double b) {
	return exp(a) / (exp(a) + exp(b));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = exp(a) / (exp(a) + exp(b))
end function
public static double code(double a, double b) {
	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
}
def code(a, b):
	return math.exp(a) / (math.exp(a) + math.exp(b))
function code(a, b)
	return Float64(exp(a) / Float64(exp(a) + exp(b)))
end
function tmp = code(a, b)
	tmp = exp(a) / (exp(a) + exp(b));
end
code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{e^{a}}{e^{a} + e^{b}}
\end{array}

Alternative 1: 100.0% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + e^{b - a}} \end{array} \]
(FPCore (a b) :precision binary64 (/ 1.0 (+ 1.0 (exp (- b a)))))
double code(double a, double b) {
	return 1.0 / (1.0 + exp((b - a)));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 1.0d0 / (1.0d0 + exp((b - a)))
end function
public static double code(double a, double b) {
	return 1.0 / (1.0 + Math.exp((b - a)));
}
def code(a, b):
	return 1.0 / (1.0 + math.exp((b - a)))
function code(a, b)
	return Float64(1.0 / Float64(1.0 + exp(Float64(b - a))))
end
function tmp = code(a, b)
	tmp = 1.0 / (1.0 + exp((b - a)));
end
code[a_, b_] := N[(1.0 / N[(1.0 + N[Exp[N[(b - a), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{1 + e^{b - a}}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{e^{a}}{e^{a} + e^{b}} \]
  2. Step-by-step derivation
    1. *-lft-identity99.6%

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

      \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
    3. associate-/r/99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
    4. remove-double-neg99.6%

      \[\leadsto \frac{1}{\frac{e^{a} + \color{blue}{\left(-\left(-e^{b}\right)\right)}}{e^{a}}} \]
    5. unsub-neg99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{a} - \left(-e^{b}\right)}}{e^{a}}} \]
    6. div-sub72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{a}}{e^{a}} - \frac{-e^{b}}{e^{a}}}} \]
    7. *-lft-identity72.3%

      \[\leadsto \frac{1}{\frac{\color{blue}{1 \cdot e^{a}}}{e^{a}} - \frac{-e^{b}}{e^{a}}} \]
    8. associate-*l/72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}} \cdot e^{a}} - \frac{-e^{b}}{e^{a}}} \]
    9. lft-mult-inverse100.0%

      \[\leadsto \frac{1}{\color{blue}{1} - \frac{-e^{b}}{e^{a}}} \]
    10. sub-neg100.0%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-\frac{-e^{b}}{e^{a}}\right)}} \]
    11. distribute-frac-neg100.0%

      \[\leadsto \frac{1}{1 + \color{blue}{\frac{-\left(-e^{b}\right)}{e^{a}}}} \]
    12. remove-double-neg100.0%

      \[\leadsto \frac{1}{1 + \frac{\color{blue}{e^{b}}}{e^{a}}} \]
    13. div-exp100.0%

      \[\leadsto \frac{1}{1 + \color{blue}{e^{b - a}}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1}{1 + e^{b - a}}} \]
  4. Add Preprocessing
  5. Final simplification100.0%

    \[\leadsto \frac{1}{1 + e^{b - a}} \]
  6. Add Preprocessing

Alternative 2: 98.6% accurate, 2.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -0.0065:\\ \;\;\;\;\frac{1}{e^{-a} - -1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} - -1}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -0.0065) (/ 1.0 (- (exp (- a)) -1.0)) (/ 1.0 (- (exp b) -1.0))))
double code(double a, double b) {
	double tmp;
	if (a <= -0.0065) {
		tmp = 1.0 / (exp(-a) - -1.0);
	} else {
		tmp = 1.0 / (exp(b) - -1.0);
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (a <= (-0.0065d0)) then
        tmp = 1.0d0 / (exp(-a) - (-1.0d0))
    else
        tmp = 1.0d0 / (exp(b) - (-1.0d0))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (a <= -0.0065) {
		tmp = 1.0 / (Math.exp(-a) - -1.0);
	} else {
		tmp = 1.0 / (Math.exp(b) - -1.0);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -0.0065:
		tmp = 1.0 / (math.exp(-a) - -1.0)
	else:
		tmp = 1.0 / (math.exp(b) - -1.0)
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -0.0065)
		tmp = Float64(1.0 / Float64(exp(Float64(-a)) - -1.0));
	else
		tmp = Float64(1.0 / Float64(exp(b) - -1.0));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -0.0065)
		tmp = 1.0 / (exp(-a) - -1.0);
	else
		tmp = 1.0 / (exp(b) - -1.0);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -0.0065], N[(1.0 / N[(N[Exp[(-a)], $MachinePrecision] - -1.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[Exp[b], $MachinePrecision] - -1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -0.0065:\\
\;\;\;\;\frac{1}{e^{-a} - -1}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{e^{b} - -1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -0.0064999999999999997

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub2.8%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-12.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg2.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp100.0%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]

    if -0.0064999999999999997 < a

    1. Initial program 99.4%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.4%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/99.4%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.4%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.4%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.4%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.4%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub99.4%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-199.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg99.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 98.9%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -0.0065:\\ \;\;\;\;\frac{1}{e^{-a} - -1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} - -1}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 93.3% accurate, 2.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -3.5 \cdot 10^{+102}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} - -1}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= a -3.5e+102)
   (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a (+ 0.5 (* a -0.16666666666666666)))))))
   (/ 1.0 (- (exp b) -1.0))))
double code(double a, double b) {
	double tmp;
	if (a <= -3.5e+102) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (exp(b) - -1.0);
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (a <= (-3.5d+102)) then
        tmp = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * (0.5d0 + (a * (-0.16666666666666666d0)))))))
    else
        tmp = 1.0d0 / (exp(b) - (-1.0d0))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (a <= -3.5e+102) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (Math.exp(b) - -1.0);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if a <= -3.5e+102:
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))))
	else:
		tmp = 1.0 / (math.exp(b) - -1.0)
	return tmp
function code(a, b)
	tmp = 0.0
	if (a <= -3.5e+102)
		tmp = Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * Float64(0.5 + Float64(a * -0.16666666666666666)))))));
	else
		tmp = Float64(1.0 / Float64(exp(b) - -1.0));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (a <= -3.5e+102)
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	else
		tmp = 1.0 / (exp(b) - -1.0);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[a, -3.5e+102], N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * N[(0.5 + N[(a * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[Exp[b], $MachinePrecision] - -1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a \leq -3.5 \cdot 10^{+102}:\\
\;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{e^{b} - -1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if a < -3.50000000000000011e102

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub0.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-10.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg0.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp100.0%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    8. Taylor expanded in a around 0 98.1%

      \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(a \cdot \left(0.5 + -0.16666666666666666 \cdot a\right) - 1\right)}} \]

    if -3.50000000000000011e102 < a

    1. Initial program 99.5%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.5%

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

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.5%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.5%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub87.7%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-187.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg87.7%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 91.3%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification92.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -3.5 \cdot 10^{+102}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} - -1}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 72.3% accurate, 6.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := b \cdot \left(b \cdot 0.16666666666666666\right)\\ \mathbf{if}\;b \leq 2.8 \cdot 10^{+77}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{elif}\;b \leq 5 \cdot 10^{+99}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + \frac{\left(b \cdot 0.5\right) \cdot \left(b \cdot 0.5\right) - t\_0 \cdot t\_0}{b \cdot 0.5 - t\_0}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (let* ((t_0 (* b (* b 0.16666666666666666))))
   (if (<= b 2.8e+77)
     (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a (+ 0.5 (* a -0.16666666666666666)))))))
     (if (<= b 5e+99)
       (/
        1.0
        (+
         2.0
         (*
          b
          (+
           1.0
           (/ (- (* (* b 0.5) (* b 0.5)) (* t_0 t_0)) (- (* b 0.5) t_0))))))
       (/
        1.0
        (+ 2.0 (* b (+ 1.0 (* b (+ 0.5 (* b 0.16666666666666666)))))))))))
double code(double a, double b) {
	double t_0 = b * (b * 0.16666666666666666);
	double tmp;
	if (b <= 2.8e+77) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else if (b <= 5e+99) {
		tmp = 1.0 / (2.0 + (b * (1.0 + ((((b * 0.5) * (b * 0.5)) - (t_0 * t_0)) / ((b * 0.5) - t_0)))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: t_0
    real(8) :: tmp
    t_0 = b * (b * 0.16666666666666666d0)
    if (b <= 2.8d+77) then
        tmp = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * (0.5d0 + (a * (-0.16666666666666666d0)))))))
    else if (b <= 5d+99) then
        tmp = 1.0d0 / (2.0d0 + (b * (1.0d0 + ((((b * 0.5d0) * (b * 0.5d0)) - (t_0 * t_0)) / ((b * 0.5d0) - t_0)))))
    else
        tmp = 1.0d0 / (2.0d0 + (b * (1.0d0 + (b * (0.5d0 + (b * 0.16666666666666666d0))))))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double t_0 = b * (b * 0.16666666666666666);
	double tmp;
	if (b <= 2.8e+77) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else if (b <= 5e+99) {
		tmp = 1.0 / (2.0 + (b * (1.0 + ((((b * 0.5) * (b * 0.5)) - (t_0 * t_0)) / ((b * 0.5) - t_0)))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	}
	return tmp;
}
def code(a, b):
	t_0 = b * (b * 0.16666666666666666)
	tmp = 0
	if b <= 2.8e+77:
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))))
	elif b <= 5e+99:
		tmp = 1.0 / (2.0 + (b * (1.0 + ((((b * 0.5) * (b * 0.5)) - (t_0 * t_0)) / ((b * 0.5) - t_0)))))
	else:
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))))
	return tmp
function code(a, b)
	t_0 = Float64(b * Float64(b * 0.16666666666666666))
	tmp = 0.0
	if (b <= 2.8e+77)
		tmp = Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * Float64(0.5 + Float64(a * -0.16666666666666666)))))));
	elseif (b <= 5e+99)
		tmp = Float64(1.0 / Float64(2.0 + Float64(b * Float64(1.0 + Float64(Float64(Float64(Float64(b * 0.5) * Float64(b * 0.5)) - Float64(t_0 * t_0)) / Float64(Float64(b * 0.5) - t_0))))));
	else
		tmp = Float64(1.0 / Float64(2.0 + Float64(b * Float64(1.0 + Float64(b * Float64(0.5 + Float64(b * 0.16666666666666666)))))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	t_0 = b * (b * 0.16666666666666666);
	tmp = 0.0;
	if (b <= 2.8e+77)
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	elseif (b <= 5e+99)
		tmp = 1.0 / (2.0 + (b * (1.0 + ((((b * 0.5) * (b * 0.5)) - (t_0 * t_0)) / ((b * 0.5) - t_0)))));
	else
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := Block[{t$95$0 = N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[b, 2.8e+77], N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * N[(0.5 + N[(a * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 5e+99], N[(1.0 / N[(2.0 + N[(b * N[(1.0 + N[(N[(N[(N[(b * 0.5), $MachinePrecision] * N[(b * 0.5), $MachinePrecision]), $MachinePrecision] - N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision] / N[(N[(b * 0.5), $MachinePrecision] - t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(2.0 + N[(b * N[(1.0 + N[(b * N[(0.5 + N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := b \cdot \left(b \cdot 0.16666666666666666\right)\\
\mathbf{if}\;b \leq 2.8 \cdot 10^{+77}:\\
\;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\

\mathbf{elif}\;b \leq 5 \cdot 10^{+99}:\\
\;\;\;\;\frac{1}{2 + b \cdot \left(1 + \frac{\left(b \cdot 0.5\right) \cdot \left(b \cdot 0.5\right) - t\_0 \cdot t\_0}{b \cdot 0.5 - t\_0}\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < 2.8e77

    1. Initial program 99.5%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.5%

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

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.5%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.5%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub73.4%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-173.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg73.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 76.7%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp76.7%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified76.7%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    8. Taylor expanded in a around 0 65.8%

      \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(a \cdot \left(0.5 + -0.16666666666666666 \cdot a\right) - 1\right)}} \]

    if 2.8e77 < b < 5.00000000000000008e99

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub37.5%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-137.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg37.5%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
    6. Taylor expanded in b around 0 8.6%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + 0.16666666666666666 \cdot b\right)\right)}} \]
    7. Step-by-step derivation
      1. *-commutative8.6%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + \color{blue}{b \cdot 0.16666666666666666}\right)\right)} \]
    8. Simplified8.6%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}} \]
    9. Step-by-step derivation
      1. distribute-lft-in8.6%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + \color{blue}{\left(b \cdot 0.5 + b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\right)} \]
      2. flip-+100.0%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + \color{blue}{\frac{\left(b \cdot 0.5\right) \cdot \left(b \cdot 0.5\right) - \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right) \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}{b \cdot 0.5 - b \cdot \left(b \cdot 0.16666666666666666\right)}}\right)} \]
    10. Applied egg-rr100.0%

      \[\leadsto \frac{1}{2 + b \cdot \left(1 + \color{blue}{\frac{\left(b \cdot 0.5\right) \cdot \left(b \cdot 0.5\right) - \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right) \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}{b \cdot 0.5 - b \cdot \left(b \cdot 0.16666666666666666\right)}}\right)} \]

    if 5.00000000000000008e99 < b

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub73.2%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-173.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
    6. Taylor expanded in b around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + 0.16666666666666666 \cdot b\right)\right)}} \]
    7. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + \color{blue}{b \cdot 0.16666666666666666}\right)\right)} \]
    8. Simplified100.0%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification74.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 2.8 \cdot 10^{+77}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{elif}\;b \leq 5 \cdot 10^{+99}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + \frac{\left(b \cdot 0.5\right) \cdot \left(b \cdot 0.5\right) - \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right) \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}{b \cdot 0.5 - b \cdot \left(b \cdot 0.16666666666666666\right)}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 67.1% accurate, 15.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 6.5 \cdot 10^{+124}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 6.5e+124)
   (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a (+ 0.5 (* a -0.16666666666666666)))))))
   (/ 1.0 (+ 2.0 (* b (+ 1.0 (* b 0.5)))))))
double code(double a, double b) {
	double tmp;
	if (b <= 6.5e+124) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (b <= 6.5d+124) then
        tmp = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * (0.5d0 + (a * (-0.16666666666666666d0)))))))
    else
        tmp = 1.0d0 / (2.0d0 + (b * (1.0d0 + (b * 0.5d0))))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (b <= 6.5e+124) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 6.5e+124:
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))))
	else:
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 6.5e+124)
		tmp = Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * Float64(0.5 + Float64(a * -0.16666666666666666)))))));
	else
		tmp = Float64(1.0 / Float64(2.0 + Float64(b * Float64(1.0 + Float64(b * 0.5)))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 6.5e+124)
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	else
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 6.5e+124], N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * N[(0.5 + N[(a * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(2.0 + N[(b * N[(1.0 + N[(b * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.5 \cdot 10^{+124}:\\
\;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 6.50000000000000008e124

    1. Initial program 99.5%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.5%

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

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.5%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.5%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub70.6%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-170.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg70.6%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 76.7%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp76.7%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified76.7%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    8. Taylor expanded in a around 0 64.5%

      \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(a \cdot \left(0.5 + -0.16666666666666666 \cdot a\right) - 1\right)}} \]

    if 6.50000000000000008e124 < b

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub78.8%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-178.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg78.8%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
    6. Taylor expanded in b around 0 84.3%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + 0.5 \cdot b\right)}} \]
    7. Step-by-step derivation
      1. *-commutative84.3%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + \color{blue}{b \cdot 0.5}\right)} \]
    8. Simplified84.3%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot 0.5\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification68.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 6.5 \cdot 10^{+124}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 71.0% accurate, 15.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 6.2 \cdot 10^{+101}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 6.2e+101)
   (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a (+ 0.5 (* a -0.16666666666666666)))))))
   (/ 1.0 (+ 2.0 (* b (+ 1.0 (* b (+ 0.5 (* b 0.16666666666666666)))))))))
double code(double a, double b) {
	double tmp;
	if (b <= 6.2e+101) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (b <= 6.2d+101) then
        tmp = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * (0.5d0 + (a * (-0.16666666666666666d0)))))))
    else
        tmp = 1.0d0 / (2.0d0 + (b * (1.0d0 + (b * (0.5d0 + (b * 0.16666666666666666d0))))))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (b <= 6.2e+101) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 6.2e+101:
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))))
	else:
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 6.2e+101)
		tmp = Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * Float64(0.5 + Float64(a * -0.16666666666666666)))))));
	else
		tmp = Float64(1.0 / Float64(2.0 + Float64(b * Float64(1.0 + Float64(b * Float64(0.5 + Float64(b * 0.16666666666666666)))))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 6.2e+101)
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * (0.5 + (a * -0.16666666666666666))))));
	else
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * (0.5 + (b * 0.16666666666666666))))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 6.2e+101], N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * N[(0.5 + N[(a * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(2.0 + N[(b * N[(1.0 + N[(b * N[(0.5 + N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 6.2 \cdot 10^{+101}:\\
\;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 6.19999999999999998e101

    1. Initial program 99.5%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.5%

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

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.5%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.5%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub72.0%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-172.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg72.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 76.2%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp76.2%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified76.2%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    8. Taylor expanded in a around 0 64.7%

      \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(a \cdot \left(0.5 + -0.16666666666666666 \cdot a\right) - 1\right)}} \]

    if 6.19999999999999998e101 < b

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub73.2%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-173.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg73.2%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
    6. Taylor expanded in b around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + 0.16666666666666666 \cdot b\right)\right)}} \]
    7. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + \color{blue}{b \cdot 0.16666666666666666}\right)\right)} \]
    8. Simplified100.0%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 6.2 \cdot 10^{+101}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot \left(0.5 + a \cdot -0.16666666666666666\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot \left(0.5 + b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 63.3% accurate, 19.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.15 \cdot 10^{+116}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= b 1.15e+116)
   (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a 0.5)))))
   (/ 1.0 (+ 2.0 (* b (+ 1.0 (* b 0.5)))))))
double code(double a, double b) {
	double tmp;
	if (b <= 1.15e+116) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (b <= 1.15d+116) then
        tmp = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * 0.5d0))))
    else
        tmp = 1.0d0 / (2.0d0 + (b * (1.0d0 + (b * 0.5d0))))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (b <= 1.15e+116) {
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
	} else {
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if b <= 1.15e+116:
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))))
	else:
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))))
	return tmp
function code(a, b)
	tmp = 0.0
	if (b <= 1.15e+116)
		tmp = Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * 0.5)))));
	else
		tmp = Float64(1.0 / Float64(2.0 + Float64(b * Float64(1.0 + Float64(b * 0.5)))));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (b <= 1.15e+116)
		tmp = 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
	else
		tmp = 1.0 / (2.0 + (b * (1.0 + (b * 0.5))));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[b, 1.15e+116], N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(2.0 + N[(b * N[(1.0 + N[(b * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq 1.15 \cdot 10^{+116}:\\
\;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < 1.14999999999999997e116

    1. Initial program 99.5%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity99.5%

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

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/99.5%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg99.5%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg99.5%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub70.9%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-170.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg70.9%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in b around 0 76.6%

      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
    6. Step-by-step derivation
      1. rec-exp76.6%

        \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    7. Simplified76.6%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
    8. Taylor expanded in a around 0 59.2%

      \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(0.5 \cdot a - 1\right)}} \]

    if 1.14999999999999997e116 < b

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Step-by-step derivation
      1. *-lft-identity100.0%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{a}}}{e^{a} + e^{b}} \]
      2. associate-*l/100.0%

        \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
      3. associate-/r/100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
      6. sub-neg100.0%

        \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
      7. div-sub77.4%

        \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
      8. neg-mul-177.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
      9. *-commutative77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
      10. associate-*r/77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
      11. metadata-eval77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
      12. distribute-neg-frac77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
      13. exp-neg77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
      14. distribute-rgt-neg-out77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
      15. exp-neg77.4%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
      16. rgt-mult-inverse100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
    4. Add Preprocessing
    5. Taylor expanded in a around 0 100.0%

      \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
    6. Taylor expanded in b around 0 82.8%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + 0.5 \cdot b\right)}} \]
    7. Step-by-step derivation
      1. *-commutative82.8%

        \[\leadsto \frac{1}{2 + b \cdot \left(1 + \color{blue}{b \cdot 0.5}\right)} \]
    8. Simplified82.8%

      \[\leadsto \frac{1}{\color{blue}{2 + b \cdot \left(1 + b \cdot 0.5\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.15 \cdot 10^{+116}:\\ \;\;\;\;\frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{2 + b \cdot \left(1 + b \cdot 0.5\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 52.8% accurate, 27.7× speedup?

\[\begin{array}{l} \\ \frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)} \end{array} \]
(FPCore (a b) :precision binary64 (/ 1.0 (+ 2.0 (* a (+ -1.0 (* a 0.5))))))
double code(double a, double b) {
	return 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 1.0d0 / (2.0d0 + (a * ((-1.0d0) + (a * 0.5d0))))
end function
public static double code(double a, double b) {
	return 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
}
def code(a, b):
	return 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))))
function code(a, b)
	return Float64(1.0 / Float64(2.0 + Float64(a * Float64(-1.0 + Float64(a * 0.5)))))
end
function tmp = code(a, b)
	tmp = 1.0 / (2.0 + (a * (-1.0 + (a * 0.5))));
end
code[a_, b_] := N[(1.0 / N[(2.0 + N[(a * N[(-1.0 + N[(a * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{e^{a}}{e^{a} + e^{b}} \]
  2. Step-by-step derivation
    1. *-lft-identity99.6%

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

      \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
    3. associate-/r/99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
    4. +-commutative99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
    5. remove-double-neg99.6%

      \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
    6. sub-neg99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
    7. div-sub72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
    8. neg-mul-172.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
    9. *-commutative72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
    10. associate-*r/72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
    11. metadata-eval72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
    12. distribute-neg-frac72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
    13. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
    14. distribute-rgt-neg-out72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
    15. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
    16. rgt-mult-inverse100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
    17. metadata-eval100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
  4. Add Preprocessing
  5. Taylor expanded in b around 0 65.9%

    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
  6. Step-by-step derivation
    1. rec-exp65.9%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  7. Simplified65.9%

    \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  8. Taylor expanded in a around 0 50.3%

    \[\leadsto \frac{1}{\color{blue}{2 + a \cdot \left(0.5 \cdot a - 1\right)}} \]
  9. Final simplification50.3%

    \[\leadsto \frac{1}{2 + a \cdot \left(-1 + a \cdot 0.5\right)} \]
  10. Add Preprocessing

Alternative 9: 39.2% accurate, 61.0× speedup?

\[\begin{array}{l} \\ 0.5 + a \cdot 0.25 \end{array} \]
(FPCore (a b) :precision binary64 (+ 0.5 (* a 0.25)))
double code(double a, double b) {
	return 0.5 + (a * 0.25);
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 0.5d0 + (a * 0.25d0)
end function
public static double code(double a, double b) {
	return 0.5 + (a * 0.25);
}
def code(a, b):
	return 0.5 + (a * 0.25)
function code(a, b)
	return Float64(0.5 + Float64(a * 0.25))
end
function tmp = code(a, b)
	tmp = 0.5 + (a * 0.25);
end
code[a_, b_] := N[(0.5 + N[(a * 0.25), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 + a \cdot 0.25
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{e^{a}}{e^{a} + e^{b}} \]
  2. Step-by-step derivation
    1. *-lft-identity99.6%

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

      \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
    3. associate-/r/99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
    4. +-commutative99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
    5. remove-double-neg99.6%

      \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
    6. sub-neg99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
    7. div-sub72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
    8. neg-mul-172.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
    9. *-commutative72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
    10. associate-*r/72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
    11. metadata-eval72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
    12. distribute-neg-frac72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
    13. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
    14. distribute-rgt-neg-out72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
    15. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
    16. rgt-mult-inverse100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
    17. metadata-eval100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
  4. Add Preprocessing
  5. Taylor expanded in b around 0 65.9%

    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
  6. Step-by-step derivation
    1. rec-exp65.9%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  7. Simplified65.9%

    \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  8. Taylor expanded in a around 0 38.0%

    \[\leadsto \color{blue}{0.5 + 0.25 \cdot a} \]
  9. Step-by-step derivation
    1. *-commutative38.0%

      \[\leadsto 0.5 + \color{blue}{a \cdot 0.25} \]
  10. Simplified38.0%

    \[\leadsto \color{blue}{0.5 + a \cdot 0.25} \]
  11. Final simplification38.0%

    \[\leadsto 0.5 + a \cdot 0.25 \]
  12. Add Preprocessing

Alternative 10: 39.8% accurate, 61.0× speedup?

\[\begin{array}{l} \\ \frac{1}{2 - a} \end{array} \]
(FPCore (a b) :precision binary64 (/ 1.0 (- 2.0 a)))
double code(double a, double b) {
	return 1.0 / (2.0 - a);
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 1.0d0 / (2.0d0 - a)
end function
public static double code(double a, double b) {
	return 1.0 / (2.0 - a);
}
def code(a, b):
	return 1.0 / (2.0 - a)
function code(a, b)
	return Float64(1.0 / Float64(2.0 - a))
end
function tmp = code(a, b)
	tmp = 1.0 / (2.0 - a);
end
code[a_, b_] := N[(1.0 / N[(2.0 - a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{2 - a}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{e^{a}}{e^{a} + e^{b}} \]
  2. Step-by-step derivation
    1. *-lft-identity99.6%

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

      \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
    3. associate-/r/99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
    4. +-commutative99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
    5. remove-double-neg99.6%

      \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
    6. sub-neg99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
    7. div-sub72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
    8. neg-mul-172.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
    9. *-commutative72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
    10. associate-*r/72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
    11. metadata-eval72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
    12. distribute-neg-frac72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
    13. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
    14. distribute-rgt-neg-out72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
    15. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
    16. rgt-mult-inverse100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
    17. metadata-eval100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
  4. Add Preprocessing
  5. Taylor expanded in b around 0 65.9%

    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} - -1} \]
  6. Step-by-step derivation
    1. rec-exp65.9%

      \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  7. Simplified65.9%

    \[\leadsto \frac{1}{\color{blue}{e^{-a}} - -1} \]
  8. Taylor expanded in a around 0 38.7%

    \[\leadsto \frac{1}{\color{blue}{2 + -1 \cdot a}} \]
  9. Step-by-step derivation
    1. neg-mul-138.7%

      \[\leadsto \frac{1}{2 + \color{blue}{\left(-a\right)}} \]
    2. unsub-neg38.7%

      \[\leadsto \frac{1}{\color{blue}{2 - a}} \]
  10. Simplified38.7%

    \[\leadsto \frac{1}{\color{blue}{2 - a}} \]
  11. Final simplification38.7%

    \[\leadsto \frac{1}{2 - a} \]
  12. Add Preprocessing

Alternative 11: 39.0% accurate, 305.0× speedup?

\[\begin{array}{l} \\ 0.5 \end{array} \]
(FPCore (a b) :precision binary64 0.5)
double code(double a, double b) {
	return 0.5;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 0.5d0
end function
public static double code(double a, double b) {
	return 0.5;
}
def code(a, b):
	return 0.5
function code(a, b)
	return 0.5
end
function tmp = code(a, b)
	tmp = 0.5;
end
code[a_, b_] := 0.5
\begin{array}{l}

\\
0.5
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{e^{a}}{e^{a} + e^{b}} \]
  2. Step-by-step derivation
    1. *-lft-identity99.6%

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

      \[\leadsto \color{blue}{\frac{1}{e^{a} + e^{b}} \cdot e^{a}} \]
    3. associate-/r/99.6%

      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
    4. +-commutative99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} + e^{a}}}{e^{a}}} \]
    5. remove-double-neg99.6%

      \[\leadsto \frac{1}{\frac{e^{b} + \color{blue}{\left(-\left(-e^{a}\right)\right)}}{e^{a}}} \]
    6. sub-neg99.6%

      \[\leadsto \frac{1}{\frac{\color{blue}{e^{b} - \left(-e^{a}\right)}}{e^{a}}} \]
    7. div-sub72.3%

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{b}}{e^{a}} - \frac{-e^{a}}{e^{a}}}} \]
    8. neg-mul-172.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{-1 \cdot e^{a}}}{e^{a}}} \]
    9. *-commutative72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \frac{\color{blue}{e^{a} \cdot -1}}{e^{a}}} \]
    10. associate-*r/72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{e^{a} \cdot \frac{-1}{e^{a}}}} \]
    11. metadata-eval72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \frac{\color{blue}{-1}}{e^{a}}} \]
    12. distribute-neg-frac72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \color{blue}{\left(-\frac{1}{e^{a}}\right)}} \]
    13. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - e^{a} \cdot \left(-\color{blue}{e^{-a}}\right)} \]
    14. distribute-rgt-neg-out72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{\left(-e^{a} \cdot e^{-a}\right)}} \]
    15. exp-neg72.3%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-e^{a} \cdot \color{blue}{\frac{1}{e^{a}}}\right)} \]
    16. rgt-mult-inverse100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \left(-\color{blue}{1}\right)} \]
    17. metadata-eval100.0%

      \[\leadsto \frac{1}{\frac{e^{b}}{e^{a}} - \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{1}{\frac{e^{b}}{e^{a}} - -1}} \]
  4. Add Preprocessing
  5. Taylor expanded in a around 0 81.8%

    \[\leadsto \frac{1}{\color{blue}{e^{b}} - -1} \]
  6. Taylor expanded in b around 0 37.9%

    \[\leadsto \color{blue}{0.5} \]
  7. Final simplification37.9%

    \[\leadsto 0.5 \]
  8. Add Preprocessing

Developer target: 100.0% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \frac{1}{1 + e^{b - a}} \end{array} \]
(FPCore (a b) :precision binary64 (/ 1.0 (+ 1.0 (exp (- b a)))))
double code(double a, double b) {
	return 1.0 / (1.0 + exp((b - a)));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = 1.0d0 / (1.0d0 + exp((b - a)))
end function
public static double code(double a, double b) {
	return 1.0 / (1.0 + Math.exp((b - a)));
}
def code(a, b):
	return 1.0 / (1.0 + math.exp((b - a)))
function code(a, b)
	return Float64(1.0 / Float64(1.0 + exp(Float64(b - a))))
end
function tmp = code(a, b)
	tmp = 1.0 / (1.0 + exp((b - a)));
end
code[a_, b_] := N[(1.0 / N[(1.0 + N[Exp[N[(b - a), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{1 + e^{b - a}}
\end{array}

Reproduce

?
herbie shell --seed 2024071 
(FPCore (a b)
  :name "Quotient of sum of exps"
  :precision binary64

  :alt
  (/ 1.0 (+ 1.0 (exp (- b a))))

  (/ (exp a) (+ (exp a) (exp b))))