quadp (p42, positive)

?

Percentage Accurate: 52.2% → 86.9%
Time: 18.7s
Precision: binary64
Cost: 14476

?

\[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
\[\begin{array}{l} \mathbf{if}\;b \leq -5 \cdot 10^{+129}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{elif}\;b \leq 10^{-300}:\\ \;\;\;\;\frac{\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot -0.5}{a}\\ \mathbf{elif}\;b \leq 200000:\\ \;\;\;\;\frac{0.5}{a \cdot \frac{-1}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))
(FPCore (a b c)
 :precision binary64
 (if (<= b -5e+129)
   (/ (- b) a)
   (if (<= b 1e-300)
     (/ (* (- b (sqrt (- (* b b) (* a (* c 4.0))))) -0.5) a)
     (if (<= b 200000.0)
       (/
        0.5
        (*
         a
         (/ -1.0 (* (/ c (+ b (hypot b (sqrt (* c (* a -4.0)))))) (* a 4.0)))))
       (/ (- c) b)))))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
double code(double a, double b, double c) {
	double tmp;
	if (b <= -5e+129) {
		tmp = -b / a;
	} else if (b <= 1e-300) {
		tmp = ((b - sqrt(((b * b) - (a * (c * 4.0))))) * -0.5) / a;
	} else if (b <= 200000.0) {
		tmp = 0.5 / (a * (-1.0 / ((c / (b + hypot(b, sqrt((c * (a * -4.0)))))) * (a * 4.0))));
	} else {
		tmp = -c / b;
	}
	return tmp;
}
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
}
public static double code(double a, double b, double c) {
	double tmp;
	if (b <= -5e+129) {
		tmp = -b / a;
	} else if (b <= 1e-300) {
		tmp = ((b - Math.sqrt(((b * b) - (a * (c * 4.0))))) * -0.5) / a;
	} else if (b <= 200000.0) {
		tmp = 0.5 / (a * (-1.0 / ((c / (b + Math.hypot(b, Math.sqrt((c * (a * -4.0)))))) * (a * 4.0))));
	} else {
		tmp = -c / b;
	}
	return tmp;
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a)
def code(a, b, c):
	tmp = 0
	if b <= -5e+129:
		tmp = -b / a
	elif b <= 1e-300:
		tmp = ((b - math.sqrt(((b * b) - (a * (c * 4.0))))) * -0.5) / a
	elif b <= 200000.0:
		tmp = 0.5 / (a * (-1.0 / ((c / (b + math.hypot(b, math.sqrt((c * (a * -4.0)))))) * (a * 4.0))))
	else:
		tmp = -c / b
	return tmp
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 code(a, b, c)
	tmp = 0.0
	if (b <= -5e+129)
		tmp = Float64(Float64(-b) / a);
	elseif (b <= 1e-300)
		tmp = Float64(Float64(Float64(b - sqrt(Float64(Float64(b * b) - Float64(a * Float64(c * 4.0))))) * -0.5) / a);
	elseif (b <= 200000.0)
		tmp = Float64(0.5 / Float64(a * Float64(-1.0 / Float64(Float64(c / Float64(b + hypot(b, sqrt(Float64(c * Float64(a * -4.0)))))) * Float64(a * 4.0)))));
	else
		tmp = Float64(Float64(-c) / b);
	end
	return tmp
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - (4.0 * (a * c))))) / (2.0 * a);
end
function tmp_2 = code(a, b, c)
	tmp = 0.0;
	if (b <= -5e+129)
		tmp = -b / a;
	elseif (b <= 1e-300)
		tmp = ((b - sqrt(((b * b) - (a * (c * 4.0))))) * -0.5) / a;
	elseif (b <= 200000.0)
		tmp = 0.5 / (a * (-1.0 / ((c / (b + hypot(b, sqrt((c * (a * -4.0)))))) * (a * 4.0))));
	else
		tmp = -c / b;
	end
	tmp_2 = tmp;
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]
code[a_, b_, c_] := If[LessEqual[b, -5e+129], N[((-b) / a), $MachinePrecision], If[LessEqual[b, 1e-300], N[(N[(N[(b - N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(a * N[(c * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -0.5), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b, 200000.0], N[(0.5 / N[(a * N[(-1.0 / N[(N[(c / N[(b + N[Sqrt[b ^ 2 + N[Sqrt[N[(c * N[(a * -4.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(a * 4.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[((-c) / b), $MachinePrecision]]]]
\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}
\begin{array}{l}
\mathbf{if}\;b \leq -5 \cdot 10^{+129}:\\
\;\;\;\;\frac{-b}{a}\\

\mathbf{elif}\;b \leq 10^{-300}:\\
\;\;\;\;\frac{\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot -0.5}{a}\\

\mathbf{elif}\;b \leq 200000:\\
\;\;\;\;\frac{0.5}{a \cdot \frac{-1}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}\\

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


\end{array}

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.

Herbie found 9 alternatives:

AlternativeAccuracySpeedup

Accuracy vs Speed

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.

Bogosity?

Bogosity

Try it out?

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original52.2%
Target70.5%
Herbie86.9%
\[\begin{array}{l} \mathbf{if}\;b < 0:\\ \;\;\;\;\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{a \cdot \frac{\left(-b\right) - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}}\\ \end{array} \]

Derivation?

  1. Split input into 4 regimes
  2. if b < -5.0000000000000003e129

    1. Initial program 55.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Simplified56.1%

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

      [Start]55.9%

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

      neg-sub0 [=>]55.9%

      \[ \frac{\color{blue}{\left(0 - b\right)} + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]

      associate-+l- [=>]55.9%

      \[ \frac{\color{blue}{0 - \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      sub0-neg [=>]55.9%

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

      neg-mul-1 [=>]55.9%

      \[ \frac{\color{blue}{-1 \cdot \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      *-commutative [=>]55.9%

      \[ \frac{\color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot -1}}{2 \cdot a} \]

      associate-*r/ [<=]55.9%

      \[ \color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot \frac{-1}{2 \cdot a}} \]
    3. Taylor expanded in b around -inf 98.1%

      \[\leadsto \color{blue}{-1 \cdot \frac{b}{a}} \]
    4. Simplified98.1%

      \[\leadsto \color{blue}{\frac{-b}{a}} \]
      Step-by-step derivation

      [Start]98.1%

      \[ -1 \cdot \frac{b}{a} \]

      associate-*r/ [=>]98.1%

      \[ \color{blue}{\frac{-1 \cdot b}{a}} \]

      mul-1-neg [=>]98.1%

      \[ \frac{\color{blue}{-b}}{a} \]

    if -5.0000000000000003e129 < b < 1.00000000000000003e-300

    1. Initial program 84.8%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Simplified84.6%

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

      [Start]84.8%

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

      neg-sub0 [=>]84.8%

      \[ \frac{\color{blue}{\left(0 - b\right)} + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]

      associate-+l- [=>]84.8%

      \[ \frac{\color{blue}{0 - \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      sub0-neg [=>]84.8%

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

      neg-mul-1 [=>]84.8%

      \[ \frac{\color{blue}{-1 \cdot \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      *-commutative [=>]84.8%

      \[ \frac{\color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot -1}}{2 \cdot a} \]

      associate-*r/ [<=]84.5%

      \[ \color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot \frac{-1}{2 \cdot a}} \]
    3. Applied egg-rr84.6%

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

      [Start]84.6%

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

      fma-udef [=>]84.6%

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

      associate-*r* [=>]84.5%

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

      metadata-eval [<=]84.5%

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

      distribute-rgt-neg-in [<=]84.5%

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

      *-commutative [<=]84.5%

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

      +-commutative [=>]84.5%

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

      sub-neg [<=]84.5%

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

      *-commutative [=>]84.5%

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

      associate-*l* [=>]84.6%

      \[ \left(b - \sqrt{b \cdot b - \color{blue}{a \cdot \left(c \cdot 4\right)}}\right) \cdot \frac{-0.5}{a} \]
    4. Applied egg-rr84.8%

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

      [Start]84.6%

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

      associate-*r/ [=>]84.8%

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

    if 1.00000000000000003e-300 < b < 2e5

    1. Initial program 63.2%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Simplified63.1%

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

      [Start]63.2%

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

      neg-sub0 [=>]63.2%

      \[ \frac{\color{blue}{\left(0 - b\right)} + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]

      associate-+l- [=>]63.2%

      \[ \frac{\color{blue}{0 - \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      sub0-neg [=>]63.2%

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

      neg-mul-1 [=>]63.2%

      \[ \frac{\color{blue}{-1 \cdot \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      *-commutative [=>]63.2%

      \[ \frac{\color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot -1}}{2 \cdot a} \]

      associate-*r/ [<=]63.1%

      \[ \color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot \frac{-1}{2 \cdot a}} \]
    3. Applied egg-rr63.2%

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

      [Start]63.1%

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

      associate-*r/ [=>]63.2%

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

      frac-2neg [=>]63.2%

      \[ \color{blue}{\frac{-\left(b - \sqrt{\mathsf{fma}\left(a, c \cdot -4, b \cdot b\right)}\right) \cdot -0.5}{-a}} \]
    4. Simplified63.2%

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

      [Start]63.2%

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

      distribute-rgt-neg-in [=>]63.2%

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

      metadata-eval [=>]63.2%

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

      *-commutative [=>]63.2%

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

      associate-/l* [=>]63.2%

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

      fma-def [<=]63.2%

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

      +-commutative [<=]63.2%

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

      fma-def [=>]63.2%

      \[ \frac{0.5}{\frac{-a}{b - \sqrt{\color{blue}{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}}}} \]
    5. Applied egg-rr62.2%

      \[\leadsto \frac{0.5}{\color{blue}{\left(-a\right) \cdot \frac{1}{b - \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]
      Step-by-step derivation

      [Start]63.2%

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

      div-inv [=>]63.1%

      \[ \frac{0.5}{\color{blue}{\left(-a\right) \cdot \frac{1}{b - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}}}} \]

      fma-udef [=>]63.1%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{b - \sqrt{\color{blue}{b \cdot b + a \cdot \left(c \cdot -4\right)}}}} \]

      add-sqr-sqrt [=>]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{b - \sqrt{b \cdot b + \color{blue}{\sqrt{a \cdot \left(c \cdot -4\right)} \cdot \sqrt{a \cdot \left(c \cdot -4\right)}}}}} \]

      hypot-def [=>]62.2%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{b - \color{blue}{\mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]
    6. Applied egg-rr62.0%

      \[\leadsto \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{b \cdot b - \mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}}} \]
      Step-by-step derivation

      [Start]62.2%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{b - \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}} \]

      flip-- [=>]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{b \cdot b - \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right) \cdot \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}}} \]

      hypot-udef [=>]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\sqrt{b \cdot b + \sqrt{a \cdot \left(c \cdot -4\right)} \cdot \sqrt{a \cdot \left(c \cdot -4\right)}}} \cdot \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      add-sqr-sqrt [<=]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \sqrt{b \cdot b + \color{blue}{a \cdot \left(c \cdot -4\right)}} \cdot \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      fma-udef [<=]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \sqrt{\color{blue}{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}} \cdot \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      hypot-udef [=>]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)} \cdot \color{blue}{\sqrt{b \cdot b + \sqrt{a \cdot \left(c \cdot -4\right)} \cdot \sqrt{a \cdot \left(c \cdot -4\right)}}}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      add-sqr-sqrt [<=]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)} \cdot \sqrt{b \cdot b + \color{blue}{a \cdot \left(c \cdot -4\right)}}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      fma-udef [<=]61.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)} \cdot \sqrt{\color{blue}{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      add-sqr-sqrt [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]
    7. Simplified72.9%

      \[\leadsto \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{0 + c \cdot \left(4 \cdot a\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}}} \]
      Step-by-step derivation

      [Start]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \mathsf{fma}\left(b, b, a \cdot \left(c \cdot -4\right)\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      fma-udef [=>]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\left(b \cdot b + a \cdot \left(c \cdot -4\right)\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      associate-*r* [=>]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(b \cdot b + \color{blue}{\left(a \cdot c\right) \cdot -4}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      *-commutative [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(b \cdot b + \color{blue}{-4 \cdot \left(a \cdot c\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      *-commutative [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(b \cdot b + -4 \cdot \color{blue}{\left(c \cdot a\right)}\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      +-commutative [=>]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\left(-4 \cdot \left(c \cdot a\right) + b \cdot b\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      associate-*r* [=>]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\color{blue}{\left(-4 \cdot c\right) \cdot a} + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      *-commutative [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\color{blue}{\left(c \cdot -4\right)} \cdot a + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      metadata-eval [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\left(c \cdot \color{blue}{\left(-4\right)}\right) \cdot a + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      distribute-rgt-neg-in [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\color{blue}{\left(-c \cdot 4\right)} \cdot a + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      *-commutative [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\color{blue}{a \cdot \left(-c \cdot 4\right)} + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      distribute-rgt-neg-in [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \left(\color{blue}{\left(-a \cdot \left(c \cdot 4\right)\right)} + b \cdot b\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      +-commutative [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\left(b \cdot b + \left(-a \cdot \left(c \cdot 4\right)\right)\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      sub-neg [<=]62.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{b \cdot b - \color{blue}{\left(b \cdot b - a \cdot \left(c \cdot 4\right)\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      associate-+l- [<=]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{\color{blue}{\left(b \cdot b - b \cdot b\right) + a \cdot \left(c \cdot 4\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      +-inverses [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{\color{blue}{0} + a \cdot \left(c \cdot 4\right)}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      *-commutative [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{0 + \color{blue}{\left(c \cdot 4\right) \cdot a}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      associate-*l* [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{0 + \color{blue}{c \cdot \left(4 \cdot a\right)}}{b + \mathsf{hypot}\left(b, \sqrt{a \cdot \left(c \cdot -4\right)}\right)}}} \]

      associate-*r* [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{0 + c \cdot \left(4 \cdot a\right)}{b + \mathsf{hypot}\left(b, \sqrt{\color{blue}{\left(a \cdot c\right) \cdot -4}}\right)}}} \]

      rem-square-sqrt [<=]0.0%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{0 + c \cdot \left(4 \cdot a\right)}{b + \mathsf{hypot}\left(b, \sqrt{\left(a \cdot c\right) \cdot \color{blue}{\left(\sqrt{-4} \cdot \sqrt{-4}\right)}}\right)}}} \]
    8. Applied egg-rr72.9%

      \[\leadsto \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{1 \cdot \frac{c \cdot \left(a \cdot 4\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}}} \]
      Step-by-step derivation

      [Start]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\frac{0 + c \cdot \left(4 \cdot a\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}} \]

      *-un-lft-identity [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{1 \cdot \frac{0 + c \cdot \left(4 \cdot a\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}}} \]

      +-lft-identity [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{1 \cdot \frac{\color{blue}{c \cdot \left(4 \cdot a\right)}}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}} \]

      *-commutative [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{1 \cdot \frac{c \cdot \color{blue}{\left(a \cdot 4\right)}}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}} \]
    9. Simplified79.1%

      \[\leadsto \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}} \]
      Step-by-step derivation

      [Start]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{1 \cdot \frac{c \cdot \left(a \cdot 4\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}} \]

      *-lft-identity [=>]72.9%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{c \cdot \left(a \cdot 4\right)}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}}}} \]

      associate-/l* [=>]79.1%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{c}{\frac{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)}{a \cdot 4}}}}} \]

      associate-/r/ [=>]79.1%

      \[ \frac{0.5}{\left(-a\right) \cdot \frac{1}{\color{blue}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}} \]

    if 2e5 < b

    1. Initial program 15.6%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]
    2. Simplified15.6%

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

      [Start]15.6%

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

      neg-sub0 [=>]15.6%

      \[ \frac{\color{blue}{\left(0 - b\right)} + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a} \]

      associate-+l- [=>]15.6%

      \[ \frac{\color{blue}{0 - \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      sub0-neg [=>]15.6%

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

      neg-mul-1 [=>]15.6%

      \[ \frac{\color{blue}{-1 \cdot \left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right)}}{2 \cdot a} \]

      *-commutative [=>]15.6%

      \[ \frac{\color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot -1}}{2 \cdot a} \]

      associate-*r/ [<=]15.6%

      \[ \color{blue}{\left(b - \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}\right) \cdot \frac{-1}{2 \cdot a}} \]
    3. Taylor expanded in b around inf 95.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
    4. Simplified95.6%

      \[\leadsto \color{blue}{\frac{-c}{b}} \]
      Step-by-step derivation

      [Start]95.6%

      \[ -1 \cdot \frac{c}{b} \]

      associate-*r/ [=>]95.6%

      \[ \color{blue}{\frac{-1 \cdot c}{b}} \]

      neg-mul-1 [<=]95.6%

      \[ \frac{\color{blue}{-c}}{b} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification89.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq -5 \cdot 10^{+129}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{elif}\;b \leq 10^{-300}:\\ \;\;\;\;\frac{\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot -0.5}{a}\\ \mathbf{elif}\;b \leq 200000:\\ \;\;\;\;\frac{0.5}{a \cdot \frac{-1}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]

Alternatives

Alternative 1
Accuracy86.9%
Cost14476
\[\begin{array}{l} \mathbf{if}\;b \leq -5 \cdot 10^{+129}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{elif}\;b \leq 10^{-300}:\\ \;\;\;\;\frac{\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot -0.5}{a}\\ \mathbf{elif}\;b \leq 200000:\\ \;\;\;\;\frac{0.5}{a \cdot \frac{-1}{\frac{c}{b + \mathsf{hypot}\left(b, \sqrt{c \cdot \left(a \cdot -4\right)}\right)} \cdot \left(a \cdot 4\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 2
Accuracy85.2%
Cost7624
\[\begin{array}{l} \mathbf{if}\;b \leq -1.4 \cdot 10^{+116}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{elif}\;b \leq 2.2 \cdot 10^{-92}:\\ \;\;\;\;\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot \frac{-0.5}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 3
Accuracy85.4%
Cost7624
\[\begin{array}{l} \mathbf{if}\;b \leq -2 \cdot 10^{+124}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{elif}\;b \leq 7.2 \cdot 10^{-92}:\\ \;\;\;\;\frac{\left(b - \sqrt{b \cdot b - a \cdot \left(c \cdot 4\right)}\right) \cdot -0.5}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 4
Accuracy79.8%
Cost7368
\[\begin{array}{l} \mathbf{if}\;b \leq -1.75 \cdot 10^{-7}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \mathbf{elif}\;b \leq 7.2 \cdot 10^{-92}:\\ \;\;\;\;\frac{-0.5}{a} \cdot \left(b - \sqrt{a \cdot \left(c \cdot -4\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 5
Accuracy79.8%
Cost7368
\[\begin{array}{l} \mathbf{if}\;b \leq -1.75 \cdot 10^{-7}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \mathbf{elif}\;b \leq 7.5 \cdot 10^{-92}:\\ \;\;\;\;\frac{-0.5 \cdot \left(b - \sqrt{c \cdot \left(a \cdot -4\right)}\right)}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 6
Accuracy67.2%
Cost580
\[\begin{array}{l} \mathbf{if}\;b \leq -1 \cdot 10^{-309}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 7
Accuracy67.1%
Cost388
\[\begin{array}{l} \mathbf{if}\;b \leq 2.4 \cdot 10^{-307}:\\ \;\;\;\;\frac{-b}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b}\\ \end{array} \]
Alternative 8
Accuracy34.6%
Cost256
\[\frac{-b}{a} \]
Alternative 9
Accuracy2.6%
Cost192
\[\frac{b}{a} \]

Reproduce?

herbie shell --seed 2023271 
(FPCore (a b c)
  :name "quadp (p42, positive)"
  :precision binary64

  :herbie-target
  (if (< b 0.0) (/ (+ (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)) (/ c (* a (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))))

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