Average Error: 34.1 → 8.5
Time: 16.8s
Precision: 64
\[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
\[\begin{array}{l} \mathbf{if}\;b_2 \le -128467017418558619648:\\ \;\;\;\;\frac{1}{2} \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\ \mathbf{elif}\;b_2 \le -3.43876958772637578815854414301947050583 \cdot 10^{-134}:\\ \;\;\;\;\frac{\frac{a \cdot c}{\frac{a \cdot c}{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}}}{a}\\ \mathbf{elif}\;b_2 \le 6.190496209585126281868131365991188760623 \cdot 10^{153}:\\ \;\;\;\;\frac{c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-1}{2} \cdot \frac{c}{b_2}\\ \end{array}\]
\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}
\begin{array}{l}
\mathbf{if}\;b_2 \le -128467017418558619648:\\
\;\;\;\;\frac{1}{2} \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\

\mathbf{elif}\;b_2 \le -3.43876958772637578815854414301947050583 \cdot 10^{-134}:\\
\;\;\;\;\frac{\frac{a \cdot c}{\frac{a \cdot c}{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}}}{a}\\

\mathbf{elif}\;b_2 \le 6.190496209585126281868131365991188760623 \cdot 10^{153}:\\
\;\;\;\;\frac{c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}\\

\mathbf{else}:\\
\;\;\;\;\frac{-1}{2} \cdot \frac{c}{b_2}\\

\end{array}
double f(double a, double b_2, double c) {
        double r25255 = b_2;
        double r25256 = -r25255;
        double r25257 = r25255 * r25255;
        double r25258 = a;
        double r25259 = c;
        double r25260 = r25258 * r25259;
        double r25261 = r25257 - r25260;
        double r25262 = sqrt(r25261);
        double r25263 = r25256 + r25262;
        double r25264 = r25263 / r25258;
        return r25264;
}

double f(double a, double b_2, double c) {
        double r25265 = b_2;
        double r25266 = -1.2846701741855862e+20;
        bool r25267 = r25265 <= r25266;
        double r25268 = 0.5;
        double r25269 = c;
        double r25270 = r25269 / r25265;
        double r25271 = r25268 * r25270;
        double r25272 = 2.0;
        double r25273 = a;
        double r25274 = r25265 / r25273;
        double r25275 = r25272 * r25274;
        double r25276 = r25271 - r25275;
        double r25277 = -3.438769587726376e-134;
        bool r25278 = r25265 <= r25277;
        double r25279 = r25273 * r25269;
        double r25280 = r25265 * r25265;
        double r25281 = r25280 - r25279;
        double r25282 = sqrt(r25281);
        double r25283 = r25282 - r25265;
        double r25284 = r25279 / r25283;
        double r25285 = r25279 / r25284;
        double r25286 = r25285 / r25273;
        double r25287 = 6.190496209585126e+153;
        bool r25288 = r25265 <= r25287;
        double r25289 = -r25265;
        double r25290 = r25289 - r25282;
        double r25291 = r25269 / r25290;
        double r25292 = -0.5;
        double r25293 = r25292 * r25270;
        double r25294 = r25288 ? r25291 : r25293;
        double r25295 = r25278 ? r25286 : r25294;
        double r25296 = r25267 ? r25276 : r25295;
        return r25296;
}

Error

Bits error versus a

Bits error versus b_2

Bits error versus c

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 4 regimes
  2. if b_2 < -1.2846701741855862e+20

    1. Initial program 34.5

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Taylor expanded around -inf 6.0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}}\]

    if -1.2846701741855862e+20 < b_2 < -3.438769587726376e-134

    1. Initial program 4.7

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Using strategy rm
    3. Applied flip-+37.0

      \[\leadsto \frac{\color{blue}{\frac{\left(-b_2\right) \cdot \left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c} \cdot \sqrt{b_2 \cdot b_2 - a \cdot c}}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{a}\]
    4. Simplified37.1

      \[\leadsto \frac{\frac{\color{blue}{a \cdot c}}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}\]
    5. Using strategy rm
    6. Applied flip--37.1

      \[\leadsto \frac{\frac{a \cdot c}{\color{blue}{\frac{\left(-b_2\right) \cdot \left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c} \cdot \sqrt{b_2 \cdot b_2 - a \cdot c}}{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}}{a}\]
    7. Simplified16.0

      \[\leadsto \frac{\frac{a \cdot c}{\frac{\color{blue}{0 + a \cdot c}}{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{a}\]
    8. Simplified16.0

      \[\leadsto \frac{\frac{a \cdot c}{\frac{0 + a \cdot c}{\color{blue}{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}}}}{a}\]

    if -3.438769587726376e-134 < b_2 < 6.190496209585126e+153

    1. Initial program 30.2

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Using strategy rm
    3. Applied flip-+31.1

      \[\leadsto \frac{\color{blue}{\frac{\left(-b_2\right) \cdot \left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c} \cdot \sqrt{b_2 \cdot b_2 - a \cdot c}}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{a}\]
    4. Simplified16.9

      \[\leadsto \frac{\frac{\color{blue}{a \cdot c}}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}\]
    5. Using strategy rm
    6. Applied *-un-lft-identity16.9

      \[\leadsto \frac{\frac{a \cdot c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}{\color{blue}{1 \cdot a}}\]
    7. Applied *-un-lft-identity16.9

      \[\leadsto \frac{\color{blue}{1 \cdot \frac{a \cdot c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}}{1 \cdot a}\]
    8. Applied times-frac16.9

      \[\leadsto \color{blue}{\frac{1}{1} \cdot \frac{\frac{a \cdot c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}}\]
    9. Simplified16.9

      \[\leadsto \color{blue}{1} \cdot \frac{\frac{a \cdot c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}}{a}\]
    10. Simplified10.5

      \[\leadsto 1 \cdot \color{blue}{\left(1 \cdot \frac{c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}\right)}\]

    if 6.190496209585126e+153 < b_2

    1. Initial program 64.0

      \[\frac{\left(-b_2\right) + \sqrt{b_2 \cdot b_2 - a \cdot c}}{a}\]
    2. Taylor expanded around inf 1.5

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b_2}}\]
  3. Recombined 4 regimes into one program.
  4. Final simplification8.5

    \[\leadsto \begin{array}{l} \mathbf{if}\;b_2 \le -128467017418558619648:\\ \;\;\;\;\frac{1}{2} \cdot \frac{c}{b_2} - 2 \cdot \frac{b_2}{a}\\ \mathbf{elif}\;b_2 \le -3.43876958772637578815854414301947050583 \cdot 10^{-134}:\\ \;\;\;\;\frac{\frac{a \cdot c}{\frac{a \cdot c}{\sqrt{b_2 \cdot b_2 - a \cdot c} - b_2}}}{a}\\ \mathbf{elif}\;b_2 \le 6.190496209585126281868131365991188760623 \cdot 10^{153}:\\ \;\;\;\;\frac{c}{\left(-b_2\right) - \sqrt{b_2 \cdot b_2 - a \cdot c}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-1}{2} \cdot \frac{c}{b_2}\\ \end{array}\]

Reproduce

herbie shell --seed 2019325 
(FPCore (a b_2 c)
  :name "quad2p (problem 3.2.1, positive)"
  :precision binary64
  (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))