Complex division, real part

Percentage Accurate: 61.5% → 85.6%
Time: 8.5s
Alternatives: 8
Speedup: 1.1×

Specification

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

\\
\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}
\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 8 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: 61.5% accurate, 1.0× speedup?

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

\\
\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}
\end{array}

Alternative 1: 85.6% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \leq \infty:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (<= (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))) INFINITY)
   (* (/ 1.0 (hypot c d)) (/ (fma a c (* b d)) (hypot c d)))
   (/ (+ b (* a (/ c d))) d)))
double code(double a, double b, double c, double d) {
	double tmp;
	if ((((a * c) + (b * d)) / ((c * c) + (d * d))) <= ((double) INFINITY)) {
		tmp = (1.0 / hypot(c, d)) * (fma(a, c, (b * d)) / hypot(c, d));
	} else {
		tmp = (b + (a * (c / d))) / d;
	}
	return tmp;
}
function code(a, b, c, d)
	tmp = 0.0
	if (Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d))) <= Inf)
		tmp = Float64(Float64(1.0 / hypot(c, d)) * Float64(fma(a, c, Float64(b * d)) / hypot(c, d)));
	else
		tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / d);
	end
	return tmp
end
code[a_, b_, c_, d_] := If[LessEqual[N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], Infinity], N[(N[(1.0 / N[Sqrt[c ^ 2 + d ^ 2], $MachinePrecision]), $MachinePrecision] * N[(N[(a * c + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[Sqrt[c ^ 2 + d ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \leq \infty:\\
\;\;\;\;\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (*.f64 a c) (*.f64 b d)) (+.f64 (*.f64 c c) (*.f64 d d))) < +inf.0

    1. Initial program 81.2%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity81.2%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt81.2%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac81.2%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define81.2%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define81.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define95.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr95.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]

    if +inf.0 < (/.f64 (+.f64 (*.f64 a c) (*.f64 b d)) (+.f64 (*.f64 c c) (*.f64 d d)))

    1. Initial program 0.0%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 50.6%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*56.4%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified56.4%

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

Alternative 2: 80.5% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -1.3 \cdot 10^{+154}:\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\ \mathbf{elif}\;d \leq -2.3 \cdot 10^{-128}:\\ \;\;\;\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}\\ \mathbf{elif}\;d \leq 5.3 \cdot 10^{-9}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{b + \frac{a}{\frac{d}{c}}}{d}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (<= d -1.3e+154)
   (/ (+ b (* a (/ c d))) d)
   (if (<= d -2.3e-128)
     (/ (+ (* a c) (* b d)) (+ (* c c) (* d d)))
     (if (<= d 5.3e-9) (/ (+ a (* b (/ d c))) c) (/ (+ b (/ a (/ d c))) d)))))
double code(double a, double b, double c, double d) {
	double tmp;
	if (d <= -1.3e+154) {
		tmp = (b + (a * (c / d))) / d;
	} else if (d <= -2.3e-128) {
		tmp = ((a * c) + (b * d)) / ((c * c) + (d * d));
	} else if (d <= 5.3e-9) {
		tmp = (a + (b * (d / c))) / c;
	} else {
		tmp = (b + (a / (d / c))) / d;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if (d <= (-1.3d+154)) then
        tmp = (b + (a * (c / d))) / d
    else if (d <= (-2.3d-128)) then
        tmp = ((a * c) + (b * d)) / ((c * c) + (d * d))
    else if (d <= 5.3d-9) then
        tmp = (a + (b * (d / c))) / c
    else
        tmp = (b + (a / (d / c))) / d
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if (d <= -1.3e+154) {
		tmp = (b + (a * (c / d))) / d;
	} else if (d <= -2.3e-128) {
		tmp = ((a * c) + (b * d)) / ((c * c) + (d * d));
	} else if (d <= 5.3e-9) {
		tmp = (a + (b * (d / c))) / c;
	} else {
		tmp = (b + (a / (d / c))) / d;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if d <= -1.3e+154:
		tmp = (b + (a * (c / d))) / d
	elif d <= -2.3e-128:
		tmp = ((a * c) + (b * d)) / ((c * c) + (d * d))
	elif d <= 5.3e-9:
		tmp = (a + (b * (d / c))) / c
	else:
		tmp = (b + (a / (d / c))) / d
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if (d <= -1.3e+154)
		tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / d);
	elseif (d <= -2.3e-128)
		tmp = Float64(Float64(Float64(a * c) + Float64(b * d)) / Float64(Float64(c * c) + Float64(d * d)));
	elseif (d <= 5.3e-9)
		tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c);
	else
		tmp = Float64(Float64(b + Float64(a / Float64(d / c))) / d);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if (d <= -1.3e+154)
		tmp = (b + (a * (c / d))) / d;
	elseif (d <= -2.3e-128)
		tmp = ((a * c) + (b * d)) / ((c * c) + (d * d));
	elseif (d <= 5.3e-9)
		tmp = (a + (b * (d / c))) / c;
	else
		tmp = (b + (a / (d / c))) / d;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[LessEqual[d, -1.3e+154], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision], If[LessEqual[d, -2.3e-128], N[(N[(N[(a * c), $MachinePrecision] + N[(b * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[d, 5.3e-9], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], N[(N[(b + N[(a / N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -1.3 \cdot 10^{+154}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\

\mathbf{elif}\;d \leq -2.3 \cdot 10^{-128}:\\
\;\;\;\;\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d}\\

\mathbf{elif}\;d \leq 5.3 \cdot 10^{-9}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\

\mathbf{else}:\\
\;\;\;\;\frac{b + \frac{a}{\frac{d}{c}}}{d}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if d < -1.29999999999999994e154

    1. Initial program 32.9%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 89.5%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*89.9%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified89.9%

      \[\leadsto \color{blue}{\frac{b + a \cdot \frac{c}{d}}{d}} \]

    if -1.29999999999999994e154 < d < -2.3000000000000001e-128

    1. Initial program 83.1%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing

    if -2.3000000000000001e-128 < d < 5.30000000000000031e-9

    1. Initial program 69.0%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity69.0%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt69.0%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac68.9%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define68.9%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define68.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define82.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr82.8%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]
    5. Taylor expanded in c around inf 90.4%

      \[\leadsto \color{blue}{\frac{a + \frac{b \cdot d}{c}}{c}} \]
    6. Step-by-step derivation
      1. associate-/l*91.2%

        \[\leadsto \frac{a + \color{blue}{b \cdot \frac{d}{c}}}{c} \]
    7. Simplified91.2%

      \[\leadsto \color{blue}{\frac{a + b \cdot \frac{d}{c}}{c}} \]

    if 5.30000000000000031e-9 < d

    1. Initial program 58.2%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 81.1%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*84.4%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified84.4%

      \[\leadsto \color{blue}{\frac{b + a \cdot \frac{c}{d}}{d}} \]
    6. Step-by-step derivation
      1. clear-num84.4%

        \[\leadsto \frac{b + a \cdot \color{blue}{\frac{1}{\frac{d}{c}}}}{d} \]
      2. un-div-inv84.6%

        \[\leadsto \frac{b + \color{blue}{\frac{a}{\frac{d}{c}}}}{d} \]
    7. Applied egg-rr84.6%

      \[\leadsto \frac{b + \color{blue}{\frac{a}{\frac{d}{c}}}}{d} \]
  3. Recombined 4 regimes into one program.
  4. Add Preprocessing

Alternative 3: 78.1% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -5.7 \cdot 10^{+49} \lor \neg \left(d \leq 10^{-6}\right):\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (or (<= d -5.7e+49) (not (<= d 1e-6)))
   (/ (+ b (* a (/ c d))) d)
   (/ (+ a (* b (/ d c))) c)))
double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -5.7e+49) || !(d <= 1e-6)) {
		tmp = (b + (a * (c / d))) / d;
	} else {
		tmp = (a + (b * (d / c))) / c;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if ((d <= (-5.7d+49)) .or. (.not. (d <= 1d-6))) then
        tmp = (b + (a * (c / d))) / d
    else
        tmp = (a + (b * (d / c))) / c
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -5.7e+49) || !(d <= 1e-6)) {
		tmp = (b + (a * (c / d))) / d;
	} else {
		tmp = (a + (b * (d / c))) / c;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if (d <= -5.7e+49) or not (d <= 1e-6):
		tmp = (b + (a * (c / d))) / d
	else:
		tmp = (a + (b * (d / c))) / c
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if ((d <= -5.7e+49) || !(d <= 1e-6))
		tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / d);
	else
		tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if ((d <= -5.7e+49) || ~((d <= 1e-6)))
		tmp = (b + (a * (c / d))) / d;
	else
		tmp = (a + (b * (d / c))) / c;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[Or[LessEqual[d, -5.7e+49], N[Not[LessEqual[d, 1e-6]], $MachinePrecision]], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -5.7 \cdot 10^{+49} \lor \neg \left(d \leq 10^{-6}\right):\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\

\mathbf{else}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if d < -5.6999999999999998e49 or 9.99999999999999955e-7 < d

    1. Initial program 52.6%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 82.1%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*83.9%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified83.9%

      \[\leadsto \color{blue}{\frac{b + a \cdot \frac{c}{d}}{d}} \]

    if -5.6999999999999998e49 < d < 9.99999999999999955e-7

    1. Initial program 74.5%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity74.5%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt74.5%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac74.4%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define74.4%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define74.4%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define85.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr85.8%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]
    5. Taylor expanded in c around inf 79.9%

      \[\leadsto \color{blue}{\frac{a + \frac{b \cdot d}{c}}{c}} \]
    6. Step-by-step derivation
      1. associate-/l*80.5%

        \[\leadsto \frac{a + \color{blue}{b \cdot \frac{d}{c}}}{c} \]
    7. Simplified80.5%

      \[\leadsto \color{blue}{\frac{a + b \cdot \frac{d}{c}}{c}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification82.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -5.7 \cdot 10^{+49} \lor \neg \left(d \leq 10^{-6}\right):\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 73.1% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -1.8 \cdot 10^{+53} \lor \neg \left(d \leq 110000000\right):\\ \;\;\;\;\frac{b}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (or (<= d -1.8e+53) (not (<= d 110000000.0)))
   (/ b d)
   (/ (+ a (* b (/ d c))) c)))
double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.8e+53) || !(d <= 110000000.0)) {
		tmp = b / d;
	} else {
		tmp = (a + (b * (d / c))) / c;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if ((d <= (-1.8d+53)) .or. (.not. (d <= 110000000.0d0))) then
        tmp = b / d
    else
        tmp = (a + (b * (d / c))) / c
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.8e+53) || !(d <= 110000000.0)) {
		tmp = b / d;
	} else {
		tmp = (a + (b * (d / c))) / c;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if (d <= -1.8e+53) or not (d <= 110000000.0):
		tmp = b / d
	else:
		tmp = (a + (b * (d / c))) / c
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if ((d <= -1.8e+53) || !(d <= 110000000.0))
		tmp = Float64(b / d);
	else
		tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if ((d <= -1.8e+53) || ~((d <= 110000000.0)))
		tmp = b / d;
	else
		tmp = (a + (b * (d / c))) / c;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[Or[LessEqual[d, -1.8e+53], N[Not[LessEqual[d, 110000000.0]], $MachinePrecision]], N[(b / d), $MachinePrecision], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -1.8 \cdot 10^{+53} \lor \neg \left(d \leq 110000000\right):\\
\;\;\;\;\frac{b}{d}\\

\mathbf{else}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if d < -1.8e53 or 1.1e8 < d

    1. Initial program 52.1%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0 72.0%

      \[\leadsto \color{blue}{\frac{b}{d}} \]

    if -1.8e53 < d < 1.1e8

    1. Initial program 74.6%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity74.6%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt74.6%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac74.6%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define74.6%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define74.6%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define85.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr85.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]
    5. Taylor expanded in c around inf 79.4%

      \[\leadsto \color{blue}{\frac{a + \frac{b \cdot d}{c}}{c}} \]
    6. Step-by-step derivation
      1. associate-/l*79.9%

        \[\leadsto \frac{a + \color{blue}{b \cdot \frac{d}{c}}}{c} \]
    7. Simplified79.9%

      \[\leadsto \color{blue}{\frac{a + b \cdot \frac{d}{c}}{c}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -1.8 \cdot 10^{+53} \lor \neg \left(d \leq 110000000\right):\\ \;\;\;\;\frac{b}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 78.2% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -2.76 \cdot 10^{+48}:\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\ \mathbf{elif}\;d \leq 6.8 \cdot 10^{-8}:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{b + \frac{a}{\frac{d}{c}}}{d}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (<= d -2.76e+48)
   (/ (+ b (* a (/ c d))) d)
   (if (<= d 6.8e-8) (/ (+ a (* b (/ d c))) c) (/ (+ b (/ a (/ d c))) d))))
double code(double a, double b, double c, double d) {
	double tmp;
	if (d <= -2.76e+48) {
		tmp = (b + (a * (c / d))) / d;
	} else if (d <= 6.8e-8) {
		tmp = (a + (b * (d / c))) / c;
	} else {
		tmp = (b + (a / (d / c))) / d;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if (d <= (-2.76d+48)) then
        tmp = (b + (a * (c / d))) / d
    else if (d <= 6.8d-8) then
        tmp = (a + (b * (d / c))) / c
    else
        tmp = (b + (a / (d / c))) / d
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if (d <= -2.76e+48) {
		tmp = (b + (a * (c / d))) / d;
	} else if (d <= 6.8e-8) {
		tmp = (a + (b * (d / c))) / c;
	} else {
		tmp = (b + (a / (d / c))) / d;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if d <= -2.76e+48:
		tmp = (b + (a * (c / d))) / d
	elif d <= 6.8e-8:
		tmp = (a + (b * (d / c))) / c
	else:
		tmp = (b + (a / (d / c))) / d
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if (d <= -2.76e+48)
		tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / d);
	elseif (d <= 6.8e-8)
		tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / c);
	else
		tmp = Float64(Float64(b + Float64(a / Float64(d / c))) / d);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if (d <= -2.76e+48)
		tmp = (b + (a * (c / d))) / d;
	elseif (d <= 6.8e-8)
		tmp = (a + (b * (d / c))) / c;
	else
		tmp = (b + (a / (d / c))) / d;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[LessEqual[d, -2.76e+48], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision], If[LessEqual[d, 6.8e-8], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], N[(N[(b + N[(a / N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / d), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -2.76 \cdot 10^{+48}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d}\\

\mathbf{elif}\;d \leq 6.8 \cdot 10^{-8}:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c}\\

\mathbf{else}:\\
\;\;\;\;\frac{b + \frac{a}{\frac{d}{c}}}{d}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if d < -2.7600000000000002e48

    1. Initial program 46.8%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 83.2%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*83.4%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified83.4%

      \[\leadsto \color{blue}{\frac{b + a \cdot \frac{c}{d}}{d}} \]

    if -2.7600000000000002e48 < d < 6.8e-8

    1. Initial program 74.5%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity74.5%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt74.5%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac74.4%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define74.4%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define74.4%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define85.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr85.8%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]
    5. Taylor expanded in c around inf 79.9%

      \[\leadsto \color{blue}{\frac{a + \frac{b \cdot d}{c}}{c}} \]
    6. Step-by-step derivation
      1. associate-/l*80.5%

        \[\leadsto \frac{a + \color{blue}{b \cdot \frac{d}{c}}}{c} \]
    7. Simplified80.5%

      \[\leadsto \color{blue}{\frac{a + b \cdot \frac{d}{c}}{c}} \]

    if 6.8e-8 < d

    1. Initial program 58.2%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in d around inf 81.1%

      \[\leadsto \color{blue}{\frac{b + \frac{a \cdot c}{d}}{d}} \]
    4. Step-by-step derivation
      1. associate-/l*84.4%

        \[\leadsto \frac{b + \color{blue}{a \cdot \frac{c}{d}}}{d} \]
    5. Simplified84.4%

      \[\leadsto \color{blue}{\frac{b + a \cdot \frac{c}{d}}{d}} \]
    6. Step-by-step derivation
      1. clear-num84.4%

        \[\leadsto \frac{b + a \cdot \color{blue}{\frac{1}{\frac{d}{c}}}}{d} \]
      2. un-div-inv84.6%

        \[\leadsto \frac{b + \color{blue}{\frac{a}{\frac{d}{c}}}}{d} \]
    7. Applied egg-rr84.6%

      \[\leadsto \frac{b + \color{blue}{\frac{a}{\frac{d}{c}}}}{d} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 6: 63.6% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -1.25 \cdot 10^{+38} \lor \neg \left(d \leq 0.0072\right):\\ \;\;\;\;\frac{b}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{c}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (or (<= d -1.25e+38) (not (<= d 0.0072))) (/ b d) (/ a c)))
double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.25e+38) || !(d <= 0.0072)) {
		tmp = b / d;
	} else {
		tmp = a / c;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if ((d <= (-1.25d+38)) .or. (.not. (d <= 0.0072d0))) then
        tmp = b / d
    else
        tmp = a / c
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.25e+38) || !(d <= 0.0072)) {
		tmp = b / d;
	} else {
		tmp = a / c;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if (d <= -1.25e+38) or not (d <= 0.0072):
		tmp = b / d
	else:
		tmp = a / c
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if ((d <= -1.25e+38) || !(d <= 0.0072))
		tmp = Float64(b / d);
	else
		tmp = Float64(a / c);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if ((d <= -1.25e+38) || ~((d <= 0.0072)))
		tmp = b / d;
	else
		tmp = a / c;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[Or[LessEqual[d, -1.25e+38], N[Not[LessEqual[d, 0.0072]], $MachinePrecision]], N[(b / d), $MachinePrecision], N[(a / c), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -1.25 \cdot 10^{+38} \lor \neg \left(d \leq 0.0072\right):\\
\;\;\;\;\frac{b}{d}\\

\mathbf{else}:\\
\;\;\;\;\frac{a}{c}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if d < -1.24999999999999992e38 or 0.0071999999999999998 < d

    1. Initial program 52.5%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0 71.1%

      \[\leadsto \color{blue}{\frac{b}{d}} \]

    if -1.24999999999999992e38 < d < 0.0071999999999999998

    1. Initial program 74.8%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in c around inf 61.5%

      \[\leadsto \color{blue}{\frac{a}{c}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification65.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -1.25 \cdot 10^{+38} \lor \neg \left(d \leq 0.0072\right):\\ \;\;\;\;\frac{b}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{c}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 43.5% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -1.35 \cdot 10^{+196} \lor \neg \left(d \leq 3.5 \cdot 10^{+174}\right):\\ \;\;\;\;\frac{a}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{c}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (or (<= d -1.35e+196) (not (<= d 3.5e+174))) (/ a d) (/ a c)))
double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.35e+196) || !(d <= 3.5e+174)) {
		tmp = a / d;
	} else {
		tmp = a / c;
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if ((d <= (-1.35d+196)) .or. (.not. (d <= 3.5d+174))) then
        tmp = a / d
    else
        tmp = a / c
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if ((d <= -1.35e+196) || !(d <= 3.5e+174)) {
		tmp = a / d;
	} else {
		tmp = a / c;
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if (d <= -1.35e+196) or not (d <= 3.5e+174):
		tmp = a / d
	else:
		tmp = a / c
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if ((d <= -1.35e+196) || !(d <= 3.5e+174))
		tmp = Float64(a / d);
	else
		tmp = Float64(a / c);
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if ((d <= -1.35e+196) || ~((d <= 3.5e+174)))
		tmp = a / d;
	else
		tmp = a / c;
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[Or[LessEqual[d, -1.35e+196], N[Not[LessEqual[d, 3.5e+174]], $MachinePrecision]], N[(a / d), $MachinePrecision], N[(a / c), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;d \leq -1.35 \cdot 10^{+196} \lor \neg \left(d \leq 3.5 \cdot 10^{+174}\right):\\
\;\;\;\;\frac{a}{d}\\

\mathbf{else}:\\
\;\;\;\;\frac{a}{c}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if d < -1.34999999999999998e196 or 3.5000000000000001e174 < d

    1. Initial program 35.9%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. *-un-lft-identity35.9%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(a \cdot c + b \cdot d\right)}}{c \cdot c + d \cdot d} \]
      2. add-sqr-sqrt35.9%

        \[\leadsto \frac{1 \cdot \left(a \cdot c + b \cdot d\right)}{\color{blue}{\sqrt{c \cdot c + d \cdot d} \cdot \sqrt{c \cdot c + d \cdot d}}} \]
      3. times-frac35.9%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{c \cdot c + d \cdot d}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}}} \]
      4. hypot-define35.9%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \cdot \frac{a \cdot c + b \cdot d}{\sqrt{c \cdot c + d \cdot d}} \]
      5. fma-define35.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\color{blue}{\mathsf{fma}\left(a, c, b \cdot d\right)}}{\sqrt{c \cdot c + d \cdot d}} \]
      6. hypot-define51.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\color{blue}{\mathsf{hypot}\left(c, d\right)}} \]
    4. Applied egg-rr51.2%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \frac{\mathsf{fma}\left(a, c, b \cdot d\right)}{\mathsf{hypot}\left(c, d\right)}} \]
    5. Taylor expanded in c around inf 27.4%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(c, d\right)} \cdot \color{blue}{a} \]
    6. Taylor expanded in c around 0 26.7%

      \[\leadsto \color{blue}{\frac{a}{d}} \]

    if -1.34999999999999998e196 < d < 3.5000000000000001e174

    1. Initial program 73.2%

      \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in c around inf 51.6%

      \[\leadsto \color{blue}{\frac{a}{c}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification46.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -1.35 \cdot 10^{+196} \lor \neg \left(d \leq 3.5 \cdot 10^{+174}\right):\\ \;\;\;\;\frac{a}{d}\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{c}\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 42.0% accurate, 5.0× speedup?

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

\\
\frac{a}{c}
\end{array}
Derivation
  1. Initial program 65.1%

    \[\frac{a \cdot c + b \cdot d}{c \cdot c + d \cdot d} \]
  2. Add Preprocessing
  3. Taylor expanded in c around inf 42.0%

    \[\leadsto \color{blue}{\frac{a}{c}} \]
  4. Add Preprocessing

Developer Target 1: 99.5% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left|d\right| < \left|c\right|:\\ \;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c + d \cdot \frac{d}{c}}\\ \mathbf{else}:\\ \;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d + c \cdot \frac{c}{d}}\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (if (< (fabs d) (fabs c))
   (/ (+ a (* b (/ d c))) (+ c (* d (/ d c))))
   (/ (+ b (* a (/ c d))) (+ d (* c (/ c d))))))
double code(double a, double b, double c, double d) {
	double tmp;
	if (fabs(d) < fabs(c)) {
		tmp = (a + (b * (d / c))) / (c + (d * (d / c)));
	} else {
		tmp = (b + (a * (c / d))) / (d + (c * (c / d)));
	}
	return tmp;
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    real(8) :: tmp
    if (abs(d) < abs(c)) then
        tmp = (a + (b * (d / c))) / (c + (d * (d / c)))
    else
        tmp = (b + (a * (c / d))) / (d + (c * (c / d)))
    end if
    code = tmp
end function
public static double code(double a, double b, double c, double d) {
	double tmp;
	if (Math.abs(d) < Math.abs(c)) {
		tmp = (a + (b * (d / c))) / (c + (d * (d / c)));
	} else {
		tmp = (b + (a * (c / d))) / (d + (c * (c / d)));
	}
	return tmp;
}
def code(a, b, c, d):
	tmp = 0
	if math.fabs(d) < math.fabs(c):
		tmp = (a + (b * (d / c))) / (c + (d * (d / c)))
	else:
		tmp = (b + (a * (c / d))) / (d + (c * (c / d)))
	return tmp
function code(a, b, c, d)
	tmp = 0.0
	if (abs(d) < abs(c))
		tmp = Float64(Float64(a + Float64(b * Float64(d / c))) / Float64(c + Float64(d * Float64(d / c))));
	else
		tmp = Float64(Float64(b + Float64(a * Float64(c / d))) / Float64(d + Float64(c * Float64(c / d))));
	end
	return tmp
end
function tmp_2 = code(a, b, c, d)
	tmp = 0.0;
	if (abs(d) < abs(c))
		tmp = (a + (b * (d / c))) / (c + (d * (d / c)));
	else
		tmp = (b + (a * (c / d))) / (d + (c * (c / d)));
	end
	tmp_2 = tmp;
end
code[a_, b_, c_, d_] := If[Less[N[Abs[d], $MachinePrecision], N[Abs[c], $MachinePrecision]], N[(N[(a + N[(b * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(c + N[(d * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(b + N[(a * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(d + N[(c * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left|d\right| < \left|c\right|:\\
\;\;\;\;\frac{a + b \cdot \frac{d}{c}}{c + d \cdot \frac{d}{c}}\\

\mathbf{else}:\\
\;\;\;\;\frac{b + a \cdot \frac{c}{d}}{d + c \cdot \frac{c}{d}}\\


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024186 
(FPCore (a b c d)
  :name "Complex division, real part"
  :precision binary64

  :alt
  (! :herbie-platform default (if (< (fabs d) (fabs c)) (/ (+ a (* b (/ d c))) (+ c (* d (/ d c)))) (/ (+ b (* a (/ c d))) (+ d (* c (/ c d))))))

  (/ (+ (* a c) (* b d)) (+ (* c c) (* d d))))