Average Error: 33.0 → 10.9
Time: 20.7s
Precision: 64
\[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}\]
\[\begin{array}{l} \mathbf{if}\;b \le -9.348931433494438 \cdot 10^{+39}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \mathbf{elif}\;b \le 1.3353078790738604 \cdot 10^{-121}:\\ \;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\ \mathbf{elif}\;b \le 1.6168702840263923 \cdot 10^{-79}:\\ \;\;\;\;-\frac{c}{b}\\ \mathbf{elif}\;b \le 1.546013236023957 \cdot 10^{-67}:\\ \;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\ \mathbf{else}:\\ \;\;\;\;-\frac{c}{b}\\ \end{array}\]
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\begin{array}{l}
\mathbf{if}\;b \le -9.348931433494438 \cdot 10^{+39}:\\
\;\;\;\;\frac{c}{b} - \frac{b}{a}\\

\mathbf{elif}\;b \le 1.3353078790738604 \cdot 10^{-121}:\\
\;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\

\mathbf{elif}\;b \le 1.6168702840263923 \cdot 10^{-79}:\\
\;\;\;\;-\frac{c}{b}\\

\mathbf{elif}\;b \le 1.546013236023957 \cdot 10^{-67}:\\
\;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\

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

\end{array}
double f(double a, double b, double c) {
        double r1970815 = b;
        double r1970816 = -r1970815;
        double r1970817 = r1970815 * r1970815;
        double r1970818 = 4.0;
        double r1970819 = a;
        double r1970820 = r1970818 * r1970819;
        double r1970821 = c;
        double r1970822 = r1970820 * r1970821;
        double r1970823 = r1970817 - r1970822;
        double r1970824 = sqrt(r1970823);
        double r1970825 = r1970816 + r1970824;
        double r1970826 = 2.0;
        double r1970827 = r1970826 * r1970819;
        double r1970828 = r1970825 / r1970827;
        return r1970828;
}

double f(double a, double b, double c) {
        double r1970829 = b;
        double r1970830 = -9.348931433494438e+39;
        bool r1970831 = r1970829 <= r1970830;
        double r1970832 = c;
        double r1970833 = r1970832 / r1970829;
        double r1970834 = a;
        double r1970835 = r1970829 / r1970834;
        double r1970836 = r1970833 - r1970835;
        double r1970837 = 1.3353078790738604e-121;
        bool r1970838 = r1970829 <= r1970837;
        double r1970839 = -r1970829;
        double r1970840 = r1970829 * r1970829;
        double r1970841 = 4.0;
        double r1970842 = r1970841 * r1970834;
        double r1970843 = r1970832 * r1970842;
        double r1970844 = r1970840 - r1970843;
        double r1970845 = sqrt(r1970844);
        double r1970846 = r1970839 + r1970845;
        double r1970847 = 0.5;
        double r1970848 = r1970847 / r1970834;
        double r1970849 = r1970846 * r1970848;
        double r1970850 = 1.6168702840263923e-79;
        bool r1970851 = r1970829 <= r1970850;
        double r1970852 = -r1970833;
        double r1970853 = 1.546013236023957e-67;
        bool r1970854 = r1970829 <= r1970853;
        double r1970855 = r1970854 ? r1970849 : r1970852;
        double r1970856 = r1970851 ? r1970852 : r1970855;
        double r1970857 = r1970838 ? r1970849 : r1970856;
        double r1970858 = r1970831 ? r1970836 : r1970857;
        return r1970858;
}

Error

Bits error versus a

Bits error versus b

Bits error versus c

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 3 regimes
  2. if b < -9.348931433494438e+39

    1. Initial program 34.0

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}\]
    2. Taylor expanded around -inf 6.2

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

    if -9.348931433494438e+39 < b < 1.3353078790738604e-121 or 1.6168702840263923e-79 < b < 1.546013236023957e-67

    1. Initial program 12.9

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}\]
    2. Using strategy rm
    3. Applied div-inv13.0

      \[\leadsto \color{blue}{\left(\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}\right) \cdot \frac{1}{2 \cdot a}}\]
    4. Simplified13.0

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

    if 1.3353078790738604e-121 < b < 1.6168702840263923e-79 or 1.546013236023957e-67 < b

    1. Initial program 50.8

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}\]
    2. Taylor expanded around inf 11.2

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}}\]
    3. Simplified11.2

      \[\leadsto \color{blue}{-\frac{c}{b}}\]
  3. Recombined 3 regimes into one program.
  4. Final simplification10.9

    \[\leadsto \begin{array}{l} \mathbf{if}\;b \le -9.348931433494438 \cdot 10^{+39}:\\ \;\;\;\;\frac{c}{b} - \frac{b}{a}\\ \mathbf{elif}\;b \le 1.3353078790738604 \cdot 10^{-121}:\\ \;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\ \mathbf{elif}\;b \le 1.6168702840263923 \cdot 10^{-79}:\\ \;\;\;\;-\frac{c}{b}\\ \mathbf{elif}\;b \le 1.546013236023957 \cdot 10^{-67}:\\ \;\;\;\;\left(\left(-b\right) + \sqrt{b \cdot b - c \cdot \left(4 \cdot a\right)}\right) \cdot \frac{\frac{1}{2}}{a}\\ \mathbf{else}:\\ \;\;\;\;-\frac{c}{b}\\ \end{array}\]

Reproduce

herbie shell --seed 2019158 
(FPCore (a b c)
  :name "Quadratic roots, full range"
  (/ (+ (- b) (sqrt (- (* b b) (* (* 4 a) c)))) (* 2 a)))