quad2m (problem 3.2.1, negative)

Percentage Accurate: 51.9% → 84.2%
Time: 8.7s
Alternatives: 6
Speedup: 15.9×

Specification

?
\[\begin{array}{l} \\ \frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 - Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 - math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{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 6 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 51.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 - Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 - math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}
\end{array}

Alternative 1: 84.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := -0.5 \cdot \frac{c}{b_2}\\ \mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;b_2 \leq -8.5 \cdot 10^{-12}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{elif}\;b_2 \leq -2.4 \cdot 10^{-69}:\\ \;\;\;\;t_0 + -0.125 \cdot \frac{a \cdot {c}^{2}}{{b_2}^{3}}\\ \mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (* -0.5 (/ c b_2))))
   (if (<= b_2 -4.5e+18)
     t_0
     (if (<= b_2 -8.5e-12)
       (/ (- (- b_2) (sqrt (* c (- a)))) a)
       (if (<= b_2 -2.4e-69)
         (+ t_0 (* -0.125 (/ (* a (pow c 2.0)) (pow b_2 3.0))))
         (if (<= b_2 2.45e+33)
           (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* c a)))) a)
           (+ (* -2.0 (/ b_2 a)) (* (/ c b_2) 0.5))))))))
double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double tmp;
	if (b_2 <= -4.5e+18) {
		tmp = t_0;
	} else if (b_2 <= -8.5e-12) {
		tmp = (-b_2 - sqrt((c * -a))) / a;
	} else if (b_2 <= -2.4e-69) {
		tmp = t_0 + (-0.125 * ((a * pow(c, 2.0)) / pow(b_2, 3.0)));
	} else if (b_2 <= 2.45e+33) {
		tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (-0.5d0) * (c / b_2)
    if (b_2 <= (-4.5d+18)) then
        tmp = t_0
    else if (b_2 <= (-8.5d-12)) then
        tmp = (-b_2 - sqrt((c * -a))) / a
    else if (b_2 <= (-2.4d-69)) then
        tmp = t_0 + ((-0.125d0) * ((a * (c ** 2.0d0)) / (b_2 ** 3.0d0)))
    else if (b_2 <= 2.45d+33) then
        tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a
    else
        tmp = ((-2.0d0) * (b_2 / a)) + ((c / b_2) * 0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double tmp;
	if (b_2 <= -4.5e+18) {
		tmp = t_0;
	} else if (b_2 <= -8.5e-12) {
		tmp = (-b_2 - Math.sqrt((c * -a))) / a;
	} else if (b_2 <= -2.4e-69) {
		tmp = t_0 + (-0.125 * ((a * Math.pow(c, 2.0)) / Math.pow(b_2, 3.0)));
	} else if (b_2 <= 2.45e+33) {
		tmp = (-b_2 - Math.sqrt(((b_2 * b_2) - (c * a)))) / a;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
def code(a, b_2, c):
	t_0 = -0.5 * (c / b_2)
	tmp = 0
	if b_2 <= -4.5e+18:
		tmp = t_0
	elif b_2 <= -8.5e-12:
		tmp = (-b_2 - math.sqrt((c * -a))) / a
	elif b_2 <= -2.4e-69:
		tmp = t_0 + (-0.125 * ((a * math.pow(c, 2.0)) / math.pow(b_2, 3.0)))
	elif b_2 <= 2.45e+33:
		tmp = (-b_2 - math.sqrt(((b_2 * b_2) - (c * a)))) / a
	else:
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5)
	return tmp
function code(a, b_2, c)
	t_0 = Float64(-0.5 * Float64(c / b_2))
	tmp = 0.0
	if (b_2 <= -4.5e+18)
		tmp = t_0;
	elseif (b_2 <= -8.5e-12)
		tmp = Float64(Float64(Float64(-b_2) - sqrt(Float64(c * Float64(-a)))) / a);
	elseif (b_2 <= -2.4e-69)
		tmp = Float64(t_0 + Float64(-0.125 * Float64(Float64(a * (c ^ 2.0)) / (b_2 ^ 3.0))));
	elseif (b_2 <= 2.45e+33)
		tmp = Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(c * a)))) / a);
	else
		tmp = Float64(Float64(-2.0 * Float64(b_2 / a)) + Float64(Float64(c / b_2) * 0.5));
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	t_0 = -0.5 * (c / b_2);
	tmp = 0.0;
	if (b_2 <= -4.5e+18)
		tmp = t_0;
	elseif (b_2 <= -8.5e-12)
		tmp = (-b_2 - sqrt((c * -a))) / a;
	elseif (b_2 <= -2.4e-69)
		tmp = t_0 + (-0.125 * ((a * (c ^ 2.0)) / (b_2 ^ 3.0)));
	elseif (b_2 <= 2.45e+33)
		tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a;
	else
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[b$95$2, -4.5e+18], t$95$0, If[LessEqual[b$95$2, -8.5e-12], N[(N[((-b$95$2) - N[Sqrt[N[(c * (-a)), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, -2.4e-69], N[(t$95$0 + N[(-0.125 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b$95$2, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[b$95$2, 2.45e+33], N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(c * a), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], N[(N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c / b$95$2), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := -0.5 \cdot \frac{c}{b_2}\\
\mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;b_2 \leq -8.5 \cdot 10^{-12}:\\
\;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\

\mathbf{elif}\;b_2 \leq -2.4 \cdot 10^{-69}:\\
\;\;\;\;t_0 + -0.125 \cdot \frac{a \cdot {c}^{2}}{{b_2}^{3}}\\

\mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\
\;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 5 regimes
  2. if b_2 < -4.5e18

    1. Initial program 12.0%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 90.9%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2}} \]

    if -4.5e18 < b_2 < -8.4999999999999997e-12

    1. Initial program 99.4%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around 0 99.4%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{-1 \cdot \left(a \cdot c\right)}}}{a} \]
    4. Step-by-step derivation
      1. associate-*r*99.4%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-1 \cdot a\right) \cdot c}}}{a} \]
      2. neg-mul-199.4%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right)} \cdot c}}{a} \]
    5. Simplified99.4%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right) \cdot c}}}{a} \]

    if -8.4999999999999997e-12 < b_2 < -2.4000000000000001e-69

    1. Initial program 37.6%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 70.6%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2} + -0.125 \cdot \frac{a \cdot {c}^{2}}{{b_2}^{3}}} \]

    if -2.4000000000000001e-69 < b_2 < 2.45000000000000007e33

    1. Initial program 84.8%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing

    if 2.45000000000000007e33 < b_2

    1. Initial program 67.3%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around inf 88.2%

      \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a} + 0.5 \cdot \frac{c}{b_2}} \]
  3. Recombined 5 regimes into one program.
  4. Final simplification87.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{elif}\;b_2 \leq -8.5 \cdot 10^{-12}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{elif}\;b_2 \leq -2.4 \cdot 10^{-69}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2} + -0.125 \cdot \frac{a \cdot {c}^{2}}{{b_2}^{3}}\\ \mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 84.4% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := -0.5 \cdot \frac{c}{b_2}\\ \mathbf{if}\;b_2 \leq -4.8 \cdot 10^{+18}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{elif}\;b_2 \leq -3 \cdot 10^{-68}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (* -0.5 (/ c b_2))))
   (if (<= b_2 -4.8e+18)
     t_0
     (if (<= b_2 -1.06e-11)
       (/ (- (- b_2) (sqrt (* c (- a)))) a)
       (if (<= b_2 -3e-68)
         t_0
         (if (<= b_2 2.45e+33)
           (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* c a)))) a)
           (+ (* -2.0 (/ b_2 a)) (* (/ c b_2) 0.5))))))))
double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double tmp;
	if (b_2 <= -4.8e+18) {
		tmp = t_0;
	} else if (b_2 <= -1.06e-11) {
		tmp = (-b_2 - sqrt((c * -a))) / a;
	} else if (b_2 <= -3e-68) {
		tmp = t_0;
	} else if (b_2 <= 2.45e+33) {
		tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (-0.5d0) * (c / b_2)
    if (b_2 <= (-4.8d+18)) then
        tmp = t_0
    else if (b_2 <= (-1.06d-11)) then
        tmp = (-b_2 - sqrt((c * -a))) / a
    else if (b_2 <= (-3d-68)) then
        tmp = t_0
    else if (b_2 <= 2.45d+33) then
        tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a
    else
        tmp = ((-2.0d0) * (b_2 / a)) + ((c / b_2) * 0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double tmp;
	if (b_2 <= -4.8e+18) {
		tmp = t_0;
	} else if (b_2 <= -1.06e-11) {
		tmp = (-b_2 - Math.sqrt((c * -a))) / a;
	} else if (b_2 <= -3e-68) {
		tmp = t_0;
	} else if (b_2 <= 2.45e+33) {
		tmp = (-b_2 - Math.sqrt(((b_2 * b_2) - (c * a)))) / a;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
def code(a, b_2, c):
	t_0 = -0.5 * (c / b_2)
	tmp = 0
	if b_2 <= -4.8e+18:
		tmp = t_0
	elif b_2 <= -1.06e-11:
		tmp = (-b_2 - math.sqrt((c * -a))) / a
	elif b_2 <= -3e-68:
		tmp = t_0
	elif b_2 <= 2.45e+33:
		tmp = (-b_2 - math.sqrt(((b_2 * b_2) - (c * a)))) / a
	else:
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5)
	return tmp
function code(a, b_2, c)
	t_0 = Float64(-0.5 * Float64(c / b_2))
	tmp = 0.0
	if (b_2 <= -4.8e+18)
		tmp = t_0;
	elseif (b_2 <= -1.06e-11)
		tmp = Float64(Float64(Float64(-b_2) - sqrt(Float64(c * Float64(-a)))) / a);
	elseif (b_2 <= -3e-68)
		tmp = t_0;
	elseif (b_2 <= 2.45e+33)
		tmp = Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(c * a)))) / a);
	else
		tmp = Float64(Float64(-2.0 * Float64(b_2 / a)) + Float64(Float64(c / b_2) * 0.5));
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	t_0 = -0.5 * (c / b_2);
	tmp = 0.0;
	if (b_2 <= -4.8e+18)
		tmp = t_0;
	elseif (b_2 <= -1.06e-11)
		tmp = (-b_2 - sqrt((c * -a))) / a;
	elseif (b_2 <= -3e-68)
		tmp = t_0;
	elseif (b_2 <= 2.45e+33)
		tmp = (-b_2 - sqrt(((b_2 * b_2) - (c * a)))) / a;
	else
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[b$95$2, -4.8e+18], t$95$0, If[LessEqual[b$95$2, -1.06e-11], N[(N[((-b$95$2) - N[Sqrt[N[(c * (-a)), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, -3e-68], t$95$0, If[LessEqual[b$95$2, 2.45e+33], N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(c * a), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], N[(N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c / b$95$2), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := -0.5 \cdot \frac{c}{b_2}\\
\mathbf{if}\;b_2 \leq -4.8 \cdot 10^{+18}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\
\;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\

\mathbf{elif}\;b_2 \leq -3 \cdot 10^{-68}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\
\;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if b_2 < -4.8e18 or -1.05999999999999993e-11 < b_2 < -3e-68

    1. Initial program 15.4%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 88.1%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2}} \]

    if -4.8e18 < b_2 < -1.05999999999999993e-11

    1. Initial program 99.4%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around 0 99.4%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{-1 \cdot \left(a \cdot c\right)}}}{a} \]
    4. Step-by-step derivation
      1. associate-*r*99.4%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-1 \cdot a\right) \cdot c}}}{a} \]
      2. neg-mul-199.4%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right)} \cdot c}}{a} \]
    5. Simplified99.4%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right) \cdot c}}}{a} \]

    if -3e-68 < b_2 < 2.45000000000000007e33

    1. Initial program 84.8%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing

    if 2.45000000000000007e33 < b_2

    1. Initial program 67.3%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around inf 88.2%

      \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a} + 0.5 \cdot \frac{c}{b_2}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification87.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -4.8 \cdot 10^{+18}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{elif}\;b_2 \leq -3 \cdot 10^{-68}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{elif}\;b_2 \leq 2.45 \cdot 10^{+33}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - c \cdot a}}{a}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 80.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := -0.5 \cdot \frac{c}{b_2}\\ t_1 := \frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;b_2 \leq -6.5 \cdot 10^{-69}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;b_2 \leq 5.7 \cdot 10^{-89}:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (* -0.5 (/ c b_2))) (t_1 (/ (- (- b_2) (sqrt (* c (- a)))) a)))
   (if (<= b_2 -4.5e+18)
     t_0
     (if (<= b_2 -1.06e-11)
       t_1
       (if (<= b_2 -6.5e-69)
         t_0
         (if (<= b_2 5.7e-89)
           t_1
           (+ (* -2.0 (/ b_2 a)) (* (/ c b_2) 0.5))))))))
double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double t_1 = (-b_2 - sqrt((c * -a))) / a;
	double tmp;
	if (b_2 <= -4.5e+18) {
		tmp = t_0;
	} else if (b_2 <= -1.06e-11) {
		tmp = t_1;
	} else if (b_2 <= -6.5e-69) {
		tmp = t_0;
	} else if (b_2 <= 5.7e-89) {
		tmp = t_1;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = (-0.5d0) * (c / b_2)
    t_1 = (-b_2 - sqrt((c * -a))) / a
    if (b_2 <= (-4.5d+18)) then
        tmp = t_0
    else if (b_2 <= (-1.06d-11)) then
        tmp = t_1
    else if (b_2 <= (-6.5d-69)) then
        tmp = t_0
    else if (b_2 <= 5.7d-89) then
        tmp = t_1
    else
        tmp = ((-2.0d0) * (b_2 / a)) + ((c / b_2) * 0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double t_0 = -0.5 * (c / b_2);
	double t_1 = (-b_2 - Math.sqrt((c * -a))) / a;
	double tmp;
	if (b_2 <= -4.5e+18) {
		tmp = t_0;
	} else if (b_2 <= -1.06e-11) {
		tmp = t_1;
	} else if (b_2 <= -6.5e-69) {
		tmp = t_0;
	} else if (b_2 <= 5.7e-89) {
		tmp = t_1;
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
def code(a, b_2, c):
	t_0 = -0.5 * (c / b_2)
	t_1 = (-b_2 - math.sqrt((c * -a))) / a
	tmp = 0
	if b_2 <= -4.5e+18:
		tmp = t_0
	elif b_2 <= -1.06e-11:
		tmp = t_1
	elif b_2 <= -6.5e-69:
		tmp = t_0
	elif b_2 <= 5.7e-89:
		tmp = t_1
	else:
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5)
	return tmp
function code(a, b_2, c)
	t_0 = Float64(-0.5 * Float64(c / b_2))
	t_1 = Float64(Float64(Float64(-b_2) - sqrt(Float64(c * Float64(-a)))) / a)
	tmp = 0.0
	if (b_2 <= -4.5e+18)
		tmp = t_0;
	elseif (b_2 <= -1.06e-11)
		tmp = t_1;
	elseif (b_2 <= -6.5e-69)
		tmp = t_0;
	elseif (b_2 <= 5.7e-89)
		tmp = t_1;
	else
		tmp = Float64(Float64(-2.0 * Float64(b_2 / a)) + Float64(Float64(c / b_2) * 0.5));
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	t_0 = -0.5 * (c / b_2);
	t_1 = (-b_2 - sqrt((c * -a))) / a;
	tmp = 0.0;
	if (b_2 <= -4.5e+18)
		tmp = t_0;
	elseif (b_2 <= -1.06e-11)
		tmp = t_1;
	elseif (b_2 <= -6.5e-69)
		tmp = t_0;
	elseif (b_2 <= 5.7e-89)
		tmp = t_1;
	else
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[((-b$95$2) - N[Sqrt[N[(c * (-a)), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]}, If[LessEqual[b$95$2, -4.5e+18], t$95$0, If[LessEqual[b$95$2, -1.06e-11], t$95$1, If[LessEqual[b$95$2, -6.5e-69], t$95$0, If[LessEqual[b$95$2, 5.7e-89], t$95$1, N[(N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c / b$95$2), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := -0.5 \cdot \frac{c}{b_2}\\
t_1 := \frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\
\mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;b_2 \leq -6.5 \cdot 10^{-69}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;b_2 \leq 5.7 \cdot 10^{-89}:\\
\;\;\;\;t_1\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -4.5e18 or -1.05999999999999993e-11 < b_2 < -6.49999999999999951e-69

    1. Initial program 15.4%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 88.1%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2}} \]

    if -4.5e18 < b_2 < -1.05999999999999993e-11 or -6.49999999999999951e-69 < b_2 < 5.7000000000000002e-89

    1. Initial program 83.0%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around 0 81.8%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{-1 \cdot \left(a \cdot c\right)}}}{a} \]
    4. Step-by-step derivation
      1. associate-*r*81.8%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-1 \cdot a\right) \cdot c}}}{a} \]
      2. neg-mul-181.8%

        \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right)} \cdot c}}{a} \]
    5. Simplified81.8%

      \[\leadsto \frac{\left(-b_2\right) - \sqrt{\color{blue}{\left(-a\right) \cdot c}}}{a} \]

    if 5.7000000000000002e-89 < b_2

    1. Initial program 74.6%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around inf 80.3%

      \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a} + 0.5 \cdot \frac{c}{b_2}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification83.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -4.5 \cdot 10^{+18}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{elif}\;b_2 \leq -1.06 \cdot 10^{-11}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{elif}\;b_2 \leq -6.5 \cdot 10^{-69}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{elif}\;b_2 \leq 5.7 \cdot 10^{-89}:\\ \;\;\;\;\frac{\left(-b_2\right) - \sqrt{c \cdot \left(-a\right)}}{a}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 68.8% accurate, 8.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -1e-310)
   (* -0.5 (/ c b_2))
   (+ (* -2.0 (/ b_2 a)) (* (/ c b_2) 0.5))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e-310) {
		tmp = -0.5 * (c / b_2);
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-1d-310)) then
        tmp = (-0.5d0) * (c / b_2)
    else
        tmp = ((-2.0d0) * (b_2 / a)) + ((c / b_2) * 0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e-310) {
		tmp = -0.5 * (c / b_2);
	} else {
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -1e-310:
		tmp = -0.5 * (c / b_2)
	else:
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5)
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -1e-310)
		tmp = Float64(-0.5 * Float64(c / b_2));
	else
		tmp = Float64(Float64(-2.0 * Float64(b_2 / a)) + Float64(Float64(c / b_2) * 0.5));
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -1e-310)
		tmp = -0.5 * (c / b_2);
	else
		tmp = (-2.0 * (b_2 / a)) + ((c / b_2) * 0.5);
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1e-310], N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision] + N[(N[(c / b$95$2), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\
\;\;\;\;-0.5 \cdot \frac{c}{b_2}\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b_2 < -9.999999999999969e-311

    1. Initial program 36.3%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 66.2%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2}} \]

    if -9.999999999999969e-311 < b_2

    1. Initial program 75.7%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around inf 63.3%

      \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a} + 0.5 \cdot \frac{c}{b_2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a} + \frac{c}{b_2} \cdot 0.5\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 68.5% accurate, 15.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a}\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -1e-310) (* -0.5 (/ c b_2)) (* -2.0 (/ b_2 a))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e-310) {
		tmp = -0.5 * (c / b_2);
	} else {
		tmp = -2.0 * (b_2 / a);
	}
	return tmp;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-1d-310)) then
        tmp = (-0.5d0) * (c / b_2)
    else
        tmp = (-2.0d0) * (b_2 / a)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e-310) {
		tmp = -0.5 * (c / b_2);
	} else {
		tmp = -2.0 * (b_2 / a);
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -1e-310:
		tmp = -0.5 * (c / b_2)
	else:
		tmp = -2.0 * (b_2 / a)
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -1e-310)
		tmp = Float64(-0.5 * Float64(c / b_2));
	else
		tmp = Float64(-2.0 * Float64(b_2 / a));
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -1e-310)
		tmp = -0.5 * (c / b_2);
	else
		tmp = -2.0 * (b_2 / a);
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1e-310], N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision], N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\
\;\;\;\;-0.5 \cdot \frac{c}{b_2}\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot \frac{b_2}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b_2 < -9.999999999999969e-311

    1. Initial program 36.3%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf 66.2%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b_2}} \]

    if -9.999999999999969e-311 < b_2

    1. Initial program 75.7%

      \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around inf 62.7%

      \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification64.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \leq -1 \cdot 10^{-310}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b_2}\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot \frac{b_2}{a}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 35.3% accurate, 22.4× speedup?

\[\begin{array}{l} \\ -2 \cdot \frac{b_2}{a} \end{array} \]
(FPCore (a b_2 c) :precision binary64 (* -2.0 (/ b_2 a)))
double code(double a, double b_2, double c) {
	return -2.0 * (b_2 / a);
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-2.0d0) * (b_2 / a)
end function
public static double code(double a, double b_2, double c) {
	return -2.0 * (b_2 / a);
}
def code(a, b_2, c):
	return -2.0 * (b_2 / a)
function code(a, b_2, c)
	return Float64(-2.0 * Float64(b_2 / a))
end
function tmp = code(a, b_2, c)
	tmp = -2.0 * (b_2 / a);
end
code[a_, b$95$2_, c_] := N[(-2.0 * N[(b$95$2 / a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
-2 \cdot \frac{b_2}{a}
\end{array}
Derivation
  1. Initial program 54.4%

    \[\frac{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}{a} \]
  2. Add Preprocessing
  3. Taylor expanded in b_2 around inf 30.3%

    \[\leadsto \color{blue}{-2 \cdot \frac{b_2}{a}} \]
  4. Final simplification30.3%

    \[\leadsto -2 \cdot \frac{b_2}{a} \]
  5. Add Preprocessing

Developer target: 99.7% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\ t_1 := \begin{array}{l} \mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\ \;\;\;\;\sqrt{\left|b_2\right| - t_0} \cdot \sqrt{\left|b_2\right| + t_0}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{hypot}\left(b_2, t_0\right)\\ \end{array}\\ \mathbf{if}\;b_2 < 0:\\ \;\;\;\;\frac{c}{t_1 - b_2}\\ \mathbf{else}:\\ \;\;\;\;\frac{b_2 + t_1}{-a}\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (* (sqrt (fabs a)) (sqrt (fabs c))))
        (t_1
         (if (== (copysign a c) a)
           (* (sqrt (- (fabs b_2) t_0)) (sqrt (+ (fabs b_2) t_0)))
           (hypot b_2 t_0))))
   (if (< b_2 0.0) (/ c (- t_1 b_2)) (/ (+ b_2 t_1) (- a)))))
double code(double a, double b_2, double c) {
	double t_0 = sqrt(fabs(a)) * sqrt(fabs(c));
	double tmp;
	if (copysign(a, c) == a) {
		tmp = sqrt((fabs(b_2) - t_0)) * sqrt((fabs(b_2) + t_0));
	} else {
		tmp = hypot(b_2, t_0);
	}
	double t_1 = tmp;
	double tmp_1;
	if (b_2 < 0.0) {
		tmp_1 = c / (t_1 - b_2);
	} else {
		tmp_1 = (b_2 + t_1) / -a;
	}
	return tmp_1;
}
public static double code(double a, double b_2, double c) {
	double t_0 = Math.sqrt(Math.abs(a)) * Math.sqrt(Math.abs(c));
	double tmp;
	if (Math.copySign(a, c) == a) {
		tmp = Math.sqrt((Math.abs(b_2) - t_0)) * Math.sqrt((Math.abs(b_2) + t_0));
	} else {
		tmp = Math.hypot(b_2, t_0);
	}
	double t_1 = tmp;
	double tmp_1;
	if (b_2 < 0.0) {
		tmp_1 = c / (t_1 - b_2);
	} else {
		tmp_1 = (b_2 + t_1) / -a;
	}
	return tmp_1;
}
def code(a, b_2, c):
	t_0 = math.sqrt(math.fabs(a)) * math.sqrt(math.fabs(c))
	tmp = 0
	if math.copysign(a, c) == a:
		tmp = math.sqrt((math.fabs(b_2) - t_0)) * math.sqrt((math.fabs(b_2) + t_0))
	else:
		tmp = math.hypot(b_2, t_0)
	t_1 = tmp
	tmp_1 = 0
	if b_2 < 0.0:
		tmp_1 = c / (t_1 - b_2)
	else:
		tmp_1 = (b_2 + t_1) / -a
	return tmp_1
function code(a, b_2, c)
	t_0 = Float64(sqrt(abs(a)) * sqrt(abs(c)))
	tmp = 0.0
	if (copysign(a, c) == a)
		tmp = Float64(sqrt(Float64(abs(b_2) - t_0)) * sqrt(Float64(abs(b_2) + t_0)));
	else
		tmp = hypot(b_2, t_0);
	end
	t_1 = tmp
	tmp_1 = 0.0
	if (b_2 < 0.0)
		tmp_1 = Float64(c / Float64(t_1 - b_2));
	else
		tmp_1 = Float64(Float64(b_2 + t_1) / Float64(-a));
	end
	return tmp_1
end
function tmp_3 = code(a, b_2, c)
	t_0 = sqrt(abs(a)) * sqrt(abs(c));
	tmp = 0.0;
	if ((sign(c) * abs(a)) == a)
		tmp = sqrt((abs(b_2) - t_0)) * sqrt((abs(b_2) + t_0));
	else
		tmp = hypot(b_2, t_0);
	end
	t_1 = tmp;
	tmp_2 = 0.0;
	if (b_2 < 0.0)
		tmp_2 = c / (t_1 - b_2);
	else
		tmp_2 = (b_2 + t_1) / -a;
	end
	tmp_3 = tmp_2;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(N[Sqrt[N[Abs[a], $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[Abs[c], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = If[Equal[N[With[{TMP1 = Abs[a], TMP2 = Sign[c]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision], a], N[(N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[b$95$2 ^ 2 + t$95$0 ^ 2], $MachinePrecision]]}, If[Less[b$95$2, 0.0], N[(c / N[(t$95$1 - b$95$2), $MachinePrecision]), $MachinePrecision], N[(N[(b$95$2 + t$95$1), $MachinePrecision] / (-a)), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\
t_1 := \begin{array}{l}
\mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\
\;\;\;\;\sqrt{\left|b_2\right| - t_0} \cdot \sqrt{\left|b_2\right| + t_0}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{hypot}\left(b_2, t_0\right)\\


\end{array}\\
\mathbf{if}\;b_2 < 0:\\
\;\;\;\;\frac{c}{t_1 - b_2}\\

\mathbf{else}:\\
\;\;\;\;\frac{b_2 + t_1}{-a}\\


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024010 
(FPCore (a b_2 c)
  :name "quad2m (problem 3.2.1, negative)"
  :precision binary64
  :herbie-expected 10

  :herbie-target
  (if (< b_2 0.0) (/ c (- (if (== (copysign a c) a) (* (sqrt (- (fabs b_2) (* (sqrt (fabs a)) (sqrt (fabs c))))) (sqrt (+ (fabs b_2) (* (sqrt (fabs a)) (sqrt (fabs c)))))) (hypot b_2 (* (sqrt (fabs a)) (sqrt (fabs c))))) b_2)) (/ (+ b_2 (if (== (copysign a c) a) (* (sqrt (- (fabs b_2) (* (sqrt (fabs a)) (sqrt (fabs c))))) (sqrt (+ (fabs b_2) (* (sqrt (fabs a)) (sqrt (fabs c)))))) (hypot b_2 (* (sqrt (fabs a)) (sqrt (fabs c)))))) (- a)))

  (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))