The quadratic formula (r2)

Percentage Accurate: 51.9% → 85.4%
Time: 12.2s
Alternatives: 9
Speedup: 2.5×

Specification

?
\[\begin{array}{l} \\ \frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = (-b - sqrt(((b * b) - (4.0d0 * (a * c))))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b - Math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
def code(a, b, c):
	return (-b - math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) - sqrt(Float64(Float64(b * b) - Float64(4.0 * Float64(a * c))))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) - N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}
\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 9 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: 51.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = (-b - sqrt(((b * b) - (4.0d0 * (a * c))))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b - Math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
def code(a, b, c):
	return (-b - math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) - sqrt(Float64(Float64(b * b) - Float64(4.0 * Float64(a * c))))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) - N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}
\end{array}

Alternative 1: 85.4% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{elif}\;b \leq 2 \cdot 10^{+116}:\\ \;\;\;\;\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{a \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;-\frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1.9e-41)
   (/ c (- b))
   (if (<= b 2e+116)
     (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* a 2.0))
     (- (/ b a)))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 2e+116) {
		tmp = (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (a * 2.0);
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1.9d-41)) then
        tmp = c / -b
    else if (b <= 2d+116) then
        tmp = (-b - sqrt(((b * b) - (4.0d0 * (a * c))))) / (a * 2.0d0)
    else
        tmp = -(b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 2e+116) {
		tmp = (-b - Math.sqrt(((b * b) - (4.0 * (a * c))))) / (a * 2.0);
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1.9e-41:
		tmp = c / -b
	elif b <= 2e+116:
		tmp = (-b - math.sqrt(((b * b) - (4.0 * (a * c))))) / (a * 2.0)
	else:
		tmp = -(b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1.9e-41)
		tmp = Float64(c / Float64(-b));
	elseif (b <= 2e+116)
		tmp = Float64(Float64(Float64(-b) - sqrt(Float64(Float64(b * b) - Float64(4.0 * Float64(a * c))))) / Float64(a * 2.0));
	else
		tmp = Float64(-Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1.9e-41)
		tmp = c / -b;
	elseif (b <= 2e+116)
		tmp = (-b - sqrt(((b * b) - (4.0 * (a * c))))) / (a * 2.0);
	else
		tmp = -(b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1.9e-41], N[(c / (-b)), $MachinePrecision], If[LessEqual[b, 2e+116], N[(N[((-b) - N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], (-N[(b / a), $MachinePrecision])]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\
\;\;\;\;\frac{c}{-b}\\

\mathbf{elif}\;b \leq 2 \cdot 10^{+116}:\\
\;\;\;\;\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{a \cdot 2}\\

\mathbf{else}:\\
\;\;\;\;-\frac{b}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < -1.8999999999999999e-41

    1. Initial program 15.4%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6495.7

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites95.7%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.8999999999999999e-41 < b < 2.00000000000000003e116

    1. Initial program 86.7%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing

    if 2.00000000000000003e116 < b

    1. Initial program 51.2%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      2. lower-neg.f64N/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      3. lower-/.f64100.0

        \[\leadsto -\color{blue}{\frac{b}{a}} \]
    5. Applied rewrites100.0%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{elif}\;b \leq 2 \cdot 10^{+116}:\\ \;\;\;\;\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{a \cdot 2}\\ \mathbf{else}:\\ \;\;\;\;-\frac{b}{a}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 85.3% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{elif}\;b \leq 2.1 \cdot 10^{+117}:\\ \;\;\;\;\frac{-0.5}{a} \cdot \left(b + \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;-\frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1.9e-41)
   (/ c (- b))
   (if (<= b 2.1e+117)
     (* (/ -0.5 a) (+ b (sqrt (fma b b (* c (* a -4.0))))))
     (- (/ b a)))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 2.1e+117) {
		tmp = (-0.5 / a) * (b + sqrt(fma(b, b, (c * (a * -4.0)))));
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (b <= -1.9e-41)
		tmp = Float64(c / Float64(-b));
	elseif (b <= 2.1e+117)
		tmp = Float64(Float64(-0.5 / a) * Float64(b + sqrt(fma(b, b, Float64(c * Float64(a * -4.0))))));
	else
		tmp = Float64(-Float64(b / a));
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[b, -1.9e-41], N[(c / (-b)), $MachinePrecision], If[LessEqual[b, 2.1e+117], N[(N[(-0.5 / a), $MachinePrecision] * N[(b + N[Sqrt[N[(b * b + N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-N[(b / a), $MachinePrecision])]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\
\;\;\;\;\frac{c}{-b}\\

\mathbf{elif}\;b \leq 2.1 \cdot 10^{+117}:\\
\;\;\;\;\frac{-0.5}{a} \cdot \left(b + \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}\right)\\

\mathbf{else}:\\
\;\;\;\;-\frac{b}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < -1.8999999999999999e-41

    1. Initial program 15.4%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6495.7

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites95.7%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.8999999999999999e-41 < b < 2.1000000000000001e117

    1. Initial program 86.7%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Applied rewrites86.5%

      \[\leadsto \color{blue}{\frac{-0.5}{a} \cdot \left(b + \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}\right)} \]

    if 2.1000000000000001e117 < b

    1. Initial program 51.2%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      2. lower-neg.f64N/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      3. lower-/.f64100.0

        \[\leadsto -\color{blue}{\frac{b}{a}} \]
    5. Applied rewrites100.0%

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

Alternative 3: 80.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{elif}\;b \leq 9 \cdot 10^{-89}:\\ \;\;\;\;\frac{b + \sqrt{a \cdot \left(c \cdot -4\right)}}{a \cdot -2}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1.9e-41)
   (/ c (- b))
   (if (<= b 9e-89)
     (/ (+ b (sqrt (* a (* c -4.0)))) (* a -2.0))
     (- (/ c b) (/ b a)))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 9e-89) {
		tmp = (b + sqrt((a * (c * -4.0)))) / (a * -2.0);
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1.9d-41)) then
        tmp = c / -b
    else if (b <= 9d-89) then
        tmp = (b + sqrt((a * (c * (-4.0d0))))) / (a * (-2.0d0))
    else
        tmp = (c / b) - (b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 9e-89) {
		tmp = (b + Math.sqrt((a * (c * -4.0)))) / (a * -2.0);
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1.9e-41:
		tmp = c / -b
	elif b <= 9e-89:
		tmp = (b + math.sqrt((a * (c * -4.0)))) / (a * -2.0)
	else:
		tmp = (c / b) - (b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1.9e-41)
		tmp = Float64(c / Float64(-b));
	elseif (b <= 9e-89)
		tmp = Float64(Float64(b + sqrt(Float64(a * Float64(c * -4.0)))) / Float64(a * -2.0));
	else
		tmp = Float64(Float64(c / b) - Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1.9e-41)
		tmp = c / -b;
	elseif (b <= 9e-89)
		tmp = (b + sqrt((a * (c * -4.0)))) / (a * -2.0);
	else
		tmp = (c / b) - (b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1.9e-41], N[(c / (-b)), $MachinePrecision], If[LessEqual[b, 9e-89], N[(N[(b + N[Sqrt[N[(a * N[(c * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(a * -2.0), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\
\;\;\;\;\frac{c}{-b}\\

\mathbf{elif}\;b \leq 9 \cdot 10^{-89}:\\
\;\;\;\;\frac{b + \sqrt{a \cdot \left(c \cdot -4\right)}}{a \cdot -2}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < -1.8999999999999999e-41

    1. Initial program 15.4%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6495.7

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites95.7%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.8999999999999999e-41 < b < 8.9999999999999998e-89

    1. Initial program 79.6%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Applied rewrites79.4%

      \[\leadsto \color{blue}{\frac{-0.5}{a} \cdot \left(b + \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}\right)} \]
    4. Taylor expanded in b around 0

      \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{-4 \cdot \left(a \cdot c\right)}}\right) \]
    5. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]
      3. lower-*.f6472.1

        \[\leadsto \frac{-0.5}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right)} \cdot -4}\right) \]
    6. Applied rewrites72.1%

      \[\leadsto \frac{-0.5}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]
    7. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right)} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right) \cdot \frac{\frac{-1}{2}}{a}} \]
      3. lift-/.f64N/A

        \[\leadsto \left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right) \cdot \color{blue}{\frac{\frac{-1}{2}}{a}} \]
      4. clear-numN/A

        \[\leadsto \left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right) \cdot \color{blue}{\frac{1}{\frac{a}{\frac{-1}{2}}}} \]
      5. un-div-invN/A

        \[\leadsto \color{blue}{\frac{b + \sqrt{\left(a \cdot c\right) \cdot -4}}{\frac{a}{\frac{-1}{2}}}} \]
      6. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{b + \sqrt{\left(a \cdot c\right) \cdot -4}}{\frac{a}{\frac{-1}{2}}}} \]
      7. div-invN/A

        \[\leadsto \frac{b + \sqrt{\mathsf{Rewrite=>}\left(lower-*.f64, \left(a \cdot \left(c \cdot -4\right)\right)\right)}}{\color{blue}{a \cdot \frac{1}{\frac{-1}{2}}}} \]
      8. metadata-evalN/A

        \[\leadsto \frac{b + \sqrt{\mathsf{Rewrite=>}\left(lower-*.f64, \left(a \cdot \left(c \cdot -4\right)\right)\right)}}{a \cdot \color{blue}{-2}} \]
      9. metadata-evalN/A

        \[\leadsto \frac{b + \sqrt{\mathsf{Rewrite=>}\left(lower-*.f64, \left(a \cdot \left(c \cdot -4\right)\right)\right)}}{a \cdot \color{blue}{\left(\mathsf{neg}\left(2\right)\right)}} \]
      10. lower-*.f64N/A

        \[\leadsto \frac{b + \sqrt{\mathsf{Rewrite=>}\left(lower-*.f64, \left(a \cdot \left(c \cdot -4\right)\right)\right)}}{\color{blue}{a \cdot \left(\mathsf{neg}\left(2\right)\right)}} \]
      11. metadata-evalN/A

        \[\leadsto \frac{b + \sqrt{\mathsf{Rewrite=>}\left(lower-*.f64, \left(a \cdot \left(c \cdot -4\right)\right)\right)}}{a \cdot \color{blue}{-2}} \]
    8. Applied rewrites72.3%

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

    if 8.9999999999999998e-89 < b

    1. Initial program 75.6%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a} + \frac{c}{b}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{c}{b} + -1 \cdot \frac{b}{a}} \]
      2. mul-1-negN/A

        \[\leadsto \frac{c}{b} + \color{blue}{\left(\mathsf{neg}\left(\frac{b}{a}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      4. lower--.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      5. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b}} - \frac{b}{a} \]
      6. lower-/.f6487.5

        \[\leadsto \frac{c}{b} - \color{blue}{\frac{b}{a}} \]
    5. Applied rewrites87.5%

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

Alternative 4: 80.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{elif}\;b \leq 9 \cdot 10^{-89}:\\ \;\;\;\;\frac{-0.5}{a} \cdot \left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1.9e-41)
   (/ c (- b))
   (if (<= b 9e-89)
     (* (/ -0.5 a) (+ b (sqrt (* (* a c) -4.0))))
     (- (/ c b) (/ b a)))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 9e-89) {
		tmp = (-0.5 / a) * (b + sqrt(((a * c) * -4.0)));
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1.9d-41)) then
        tmp = c / -b
    else if (b <= 9d-89) then
        tmp = ((-0.5d0) / a) * (b + sqrt(((a * c) * (-4.0d0))))
    else
        tmp = (c / b) - (b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.9e-41) {
		tmp = c / -b;
	} else if (b <= 9e-89) {
		tmp = (-0.5 / a) * (b + Math.sqrt(((a * c) * -4.0)));
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1.9e-41:
		tmp = c / -b
	elif b <= 9e-89:
		tmp = (-0.5 / a) * (b + math.sqrt(((a * c) * -4.0)))
	else:
		tmp = (c / b) - (b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1.9e-41)
		tmp = Float64(c / Float64(-b));
	elseif (b <= 9e-89)
		tmp = Float64(Float64(-0.5 / a) * Float64(b + sqrt(Float64(Float64(a * c) * -4.0))));
	else
		tmp = Float64(Float64(c / b) - Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1.9e-41)
		tmp = c / -b;
	elseif (b <= 9e-89)
		tmp = (-0.5 / a) * (b + sqrt(((a * c) * -4.0)));
	else
		tmp = (c / b) - (b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1.9e-41], N[(c / (-b)), $MachinePrecision], If[LessEqual[b, 9e-89], N[(N[(-0.5 / a), $MachinePrecision] * N[(b + N[Sqrt[N[(N[(a * c), $MachinePrecision] * -4.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.9 \cdot 10^{-41}:\\
\;\;\;\;\frac{c}{-b}\\

\mathbf{elif}\;b \leq 9 \cdot 10^{-89}:\\
\;\;\;\;\frac{-0.5}{a} \cdot \left(b + \sqrt{\left(a \cdot c\right) \cdot -4}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b < -1.8999999999999999e-41

    1. Initial program 15.4%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6495.7

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites95.7%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.8999999999999999e-41 < b < 8.9999999999999998e-89

    1. Initial program 79.6%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Applied rewrites79.4%

      \[\leadsto \color{blue}{\frac{-0.5}{a} \cdot \left(b + \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}\right)} \]
    4. Taylor expanded in b around 0

      \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{-4 \cdot \left(a \cdot c\right)}}\right) \]
    5. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto \frac{\frac{-1}{2}}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]
      3. lower-*.f6472.1

        \[\leadsto \frac{-0.5}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right)} \cdot -4}\right) \]
    6. Applied rewrites72.1%

      \[\leadsto \frac{-0.5}{a} \cdot \left(b + \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right) \]

    if 8.9999999999999998e-89 < b

    1. Initial program 75.6%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a} + \frac{c}{b}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{c}{b} + -1 \cdot \frac{b}{a}} \]
      2. mul-1-negN/A

        \[\leadsto \frac{c}{b} + \color{blue}{\left(\mathsf{neg}\left(\frac{b}{a}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      4. lower--.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      5. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b}} - \frac{b}{a} \]
      6. lower-/.f6487.5

        \[\leadsto \frac{c}{b} - \color{blue}{\frac{b}{a}} \]
    5. Applied rewrites87.5%

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

Alternative 5: 68.3% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1 \cdot 10^{-309}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1e-309) (/ c (- b)) (- (/ c b) (/ b a))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1e-309) {
		tmp = c / -b;
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1d-309)) then
        tmp = c / -b
    else
        tmp = (c / b) - (b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1e-309) {
		tmp = c / -b;
	} else {
		tmp = (c / b) - (b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1e-309:
		tmp = c / -b
	else:
		tmp = (c / b) - (b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1e-309)
		tmp = Float64(c / Float64(-b));
	else
		tmp = Float64(Float64(c / b) - Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1e-309)
		tmp = c / -b;
	else
		tmp = (c / b) - (b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1e-309], N[(c / (-b)), $MachinePrecision], N[(N[(c / b), $MachinePrecision] - N[(b / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1 \cdot 10^{-309}:\\
\;\;\;\;\frac{c}{-b}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < -1.000000000000002e-309

    1. Initial program 35.2%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6470.8

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites70.8%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.000000000000002e-309 < b

    1. Initial program 77.8%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a} + \frac{c}{b}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{c}{b} + -1 \cdot \frac{b}{a}} \]
      2. mul-1-negN/A

        \[\leadsto \frac{c}{b} + \color{blue}{\left(\mathsf{neg}\left(\frac{b}{a}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      4. lower--.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b} - \frac{b}{a}} \]
      5. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{b}} - \frac{b}{a} \]
      6. lower-/.f6469.0

        \[\leadsto \frac{c}{b} - \color{blue}{\frac{b}{a}} \]
    5. Applied rewrites69.0%

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

Alternative 6: 68.1% accurate, 2.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1 \cdot 10^{-309}:\\ \;\;\;\;\frac{c}{-b}\\ \mathbf{else}:\\ \;\;\;\;-\frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= b -1e-309) (/ c (- b)) (- (/ b a))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1e-309) {
		tmp = c / -b;
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1d-309)) then
        tmp = c / -b
    else
        tmp = -(b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1e-309) {
		tmp = c / -b;
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1e-309:
		tmp = c / -b
	else:
		tmp = -(b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1e-309)
		tmp = Float64(c / Float64(-b));
	else
		tmp = Float64(-Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1e-309)
		tmp = c / -b;
	else
		tmp = -(b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1e-309], N[(c / (-b)), $MachinePrecision], (-N[(b / a), $MachinePrecision])]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1 \cdot 10^{-309}:\\
\;\;\;\;\frac{c}{-b}\\

\mathbf{else}:\\
\;\;\;\;-\frac{b}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < -1.000000000000002e-309

    1. Initial program 35.2%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{c}{b}\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto \color{blue}{\frac{c}{\mathsf{neg}\left(b\right)}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{-1 \cdot b}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{c}{-1 \cdot b}} \]
      5. mul-1-negN/A

        \[\leadsto \frac{c}{\color{blue}{\mathsf{neg}\left(b\right)}} \]
      6. lower-neg.f6470.8

        \[\leadsto \frac{c}{\color{blue}{-b}} \]
    5. Applied rewrites70.8%

      \[\leadsto \color{blue}{\frac{c}{-b}} \]

    if -1.000000000000002e-309 < b

    1. Initial program 77.8%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      2. lower-neg.f64N/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      3. lower-/.f6468.5

        \[\leadsto -\color{blue}{\frac{b}{a}} \]
    5. Applied rewrites68.5%

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

Alternative 7: 43.7% accurate, 2.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq -1.7 \cdot 10^{+23}:\\ \;\;\;\;\frac{c}{b}\\ \mathbf{else}:\\ \;\;\;\;-\frac{b}{a}\\ \end{array} \end{array} \]
(FPCore (a b c) :precision binary64 (if (<= b -1.7e+23) (/ c b) (- (/ b a))))
double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.7e+23) {
		tmp = c / b;
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b <= (-1.7d+23)) then
        tmp = c / b
    else
        tmp = -(b / a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -1.7e+23) {
		tmp = c / b;
	} else {
		tmp = -(b / a);
	}
	return tmp;
}
def code(a, b, c):
	tmp = 0
	if b <= -1.7e+23:
		tmp = c / b
	else:
		tmp = -(b / a)
	return tmp
function code(a, b, c)
	tmp = 0.0
	if (b <= -1.7e+23)
		tmp = Float64(c / b);
	else
		tmp = Float64(-Float64(b / a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -1.7e+23)
		tmp = c / b;
	else
		tmp = -(b / a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := If[LessEqual[b, -1.7e+23], N[(c / b), $MachinePrecision], (-N[(b / a), $MachinePrecision])]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b \leq -1.7 \cdot 10^{+23}:\\
\;\;\;\;\frac{c}{b}\\

\mathbf{else}:\\
\;\;\;\;-\frac{b}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b < -1.69999999999999996e23

    1. Initial program 13.1%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Applied rewrites3.0%

      \[\leadsto \color{blue}{\frac{0.5}{\frac{1}{b - \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}} \cdot a}} \]
    4. Taylor expanded in b around inf

      \[\leadsto \color{blue}{\frac{c}{b}} \]
    5. Step-by-step derivation
      1. lower-/.f6439.0

        \[\leadsto \color{blue}{\frac{c}{b}} \]
    6. Applied rewrites39.0%

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

    if -1.69999999999999996e23 < b

    1. Initial program 74.9%

      \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in b around inf

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a}} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      2. lower-neg.f64N/A

        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{b}{a}\right)} \]
      3. lower-/.f6450.0

        \[\leadsto -\color{blue}{\frac{b}{a}} \]
    5. Applied rewrites50.0%

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

Alternative 8: 10.9% accurate, 4.2× speedup?

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

\\
\frac{c}{b}
\end{array}
Derivation
  1. Initial program 56.8%

    \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
  2. Add Preprocessing
  3. Applied rewrites33.7%

    \[\leadsto \color{blue}{\frac{0.5}{\frac{1}{b - \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}} \cdot a}} \]
  4. Taylor expanded in b around inf

    \[\leadsto \color{blue}{\frac{c}{b}} \]
  5. Step-by-step derivation
    1. lower-/.f6413.6

      \[\leadsto \color{blue}{\frac{c}{b}} \]
  6. Applied rewrites13.6%

    \[\leadsto \color{blue}{\frac{c}{b}} \]
  7. Add Preprocessing

Alternative 9: 2.5% accurate, 4.2× speedup?

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

\\
\frac{b}{a}
\end{array}
Derivation
  1. Initial program 56.8%

    \[\frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
  2. Add Preprocessing
  3. Applied rewrites33.7%

    \[\leadsto \color{blue}{\frac{0.5}{\frac{1}{b - \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -4\right)\right)}} \cdot a}} \]
  4. Taylor expanded in b around -inf

    \[\leadsto \color{blue}{\frac{b}{a}} \]
  5. Step-by-step derivation
    1. lower-/.f642.3

      \[\leadsto \color{blue}{\frac{b}{a}} \]
  6. Applied rewrites2.3%

    \[\leadsto \color{blue}{\frac{b}{a}} \]
  7. Add Preprocessing

Developer Target 1: 70.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\\ \mathbf{if}\;b < 0:\\ \;\;\;\;\frac{c}{a \cdot \frac{\left(-b\right) + t\_0}{2 \cdot a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-b\right) - t\_0}{2 \cdot a}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (let* ((t_0 (sqrt (- (* b b) (* 4.0 (* a c))))))
   (if (< b 0.0)
     (/ c (* a (/ (+ (- b) t_0) (* 2.0 a))))
     (/ (- (- b) t_0) (* 2.0 a)))))
double code(double a, double b, double c) {
	double t_0 = sqrt(((b * b) - (4.0 * (a * c))));
	double tmp;
	if (b < 0.0) {
		tmp = c / (a * ((-b + t_0) / (2.0 * a)));
	} else {
		tmp = (-b - t_0) / (2.0 * a);
	}
	return tmp;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: t_0
    real(8) :: tmp
    t_0 = sqrt(((b * b) - (4.0d0 * (a * c))))
    if (b < 0.0d0) then
        tmp = c / (a * ((-b + t_0) / (2.0d0 * a)))
    else
        tmp = (-b - t_0) / (2.0d0 * a)
    end if
    code = tmp
end function
public static double code(double a, double b, double c) {
	double t_0 = Math.sqrt(((b * b) - (4.0 * (a * c))));
	double tmp;
	if (b < 0.0) {
		tmp = c / (a * ((-b + t_0) / (2.0 * a)));
	} else {
		tmp = (-b - t_0) / (2.0 * a);
	}
	return tmp;
}
def code(a, b, c):
	t_0 = math.sqrt(((b * b) - (4.0 * (a * c))))
	tmp = 0
	if b < 0.0:
		tmp = c / (a * ((-b + t_0) / (2.0 * a)))
	else:
		tmp = (-b - t_0) / (2.0 * a)
	return tmp
function code(a, b, c)
	t_0 = sqrt(Float64(Float64(b * b) - Float64(4.0 * Float64(a * c))))
	tmp = 0.0
	if (b < 0.0)
		tmp = Float64(c / Float64(a * Float64(Float64(Float64(-b) + t_0) / Float64(2.0 * a))));
	else
		tmp = Float64(Float64(Float64(-b) - t_0) / Float64(2.0 * a));
	end
	return tmp
end
function tmp_2 = code(a, b, c)
	t_0 = sqrt(((b * b) - (4.0 * (a * c))));
	tmp = 0.0;
	if (b < 0.0)
		tmp = c / (a * ((-b + t_0) / (2.0 * a)));
	else
		tmp = (-b - t_0) / (2.0 * a);
	end
	tmp_2 = tmp;
end
code[a_, b_, c_] := Block[{t$95$0 = N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(4.0 * N[(a * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[Less[b, 0.0], N[(c / N[(a * N[(N[((-b) + t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[((-b) - t$95$0), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\\
\mathbf{if}\;b < 0:\\
\;\;\;\;\frac{c}{a \cdot \frac{\left(-b\right) + t\_0}{2 \cdot a}}\\

\mathbf{else}:\\
\;\;\;\;\frac{\left(-b\right) - t\_0}{2 \cdot a}\\


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024232 
(FPCore (a b c)
  :name "The quadratic formula (r2)"
  :precision binary64

  :alt
  (! :herbie-platform default (let ((d (sqrt (- (* b b) (* 4 (* a c)))))) (let ((r1 (/ (+ (- b) d) (* 2 a)))) (let ((r2 (/ (- (- b) d) (* 2 a)))) (if (< b 0) (/ c (* a r1)) r2)))))

  (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))