Cubic critical, narrow range

Percentage Accurate: 54.9% → 99.1%
Time: 13.0s
Alternatives: 12
Speedup: 2.9×

Specification

?
\[\left(\left(1.0536712127723509 \cdot 10^{-8} < a \land a < 94906265.62425156\right) \land \left(1.0536712127723509 \cdot 10^{-8} < b \land b < 94906265.62425156\right)\right) \land \left(1.0536712127723509 \cdot 10^{-8} < c \land c < 94906265.62425156\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \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 12 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: 54.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}

Alternative 1: 99.1% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{\left(\left(3 \cdot c\right) \cdot a\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  (* (* (* 3.0 c) a) (/ 0.3333333333333333 a))
  (- (- b) (sqrt (* c (fma a -3.0 (/ (* b b) c)))))))
double code(double a, double b, double c) {
	return (((3.0 * c) * a) * (0.3333333333333333 / a)) / (-b - sqrt((c * fma(a, -3.0, ((b * b) / c)))));
}
function code(a, b, c)
	return Float64(Float64(Float64(Float64(3.0 * c) * a) * Float64(0.3333333333333333 / a)) / Float64(Float64(-b) - sqrt(Float64(c * fma(a, -3.0, Float64(Float64(b * b) / c))))))
end
code[a_, b_, c_] := N[(N[(N[(N[(3.0 * c), $MachinePrecision] * a), $MachinePrecision] * N[(0.3333333333333333 / a), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(c * N[(a * -3.0 + N[(N[(b * b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(\left(3 \cdot c\right) \cdot a\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}}
\end{array}
Derivation
  1. Initial program 57.6%

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

    \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
  4. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
    2. cancel-sign-sub-invN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\left(\frac{{b}^{2}}{c} + \left(\mathsf{neg}\left(3\right)\right) \cdot a\right)}}}{3 \cdot a} \]
    3. metadata-evalN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{{b}^{2}}{c} + \color{blue}{-3} \cdot a\right)}}{3 \cdot a} \]
    4. unpow2N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{\color{blue}{b \cdot b}}{c} + -3 \cdot a\right)}}{3 \cdot a} \]
    5. associate-/l*N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\color{blue}{b \cdot \frac{b}{c}} + -3 \cdot a\right)}}{3 \cdot a} \]
    6. lower-fma.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\mathsf{fma}\left(b, \frac{b}{c}, -3 \cdot a\right)}}}{3 \cdot a} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \color{blue}{\frac{b}{c}}, -3 \cdot a\right)}}{3 \cdot a} \]
    8. *-commutativeN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
    9. lower-*.f6457.3

      \[\leadsto \frac{\left(-b\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
  5. Simplified57.3%

    \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, a \cdot -3\right)}}}{3 \cdot a} \]
  6. Applied egg-rr58.1%

    \[\leadsto \color{blue}{\frac{\left(b \cdot b - c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}}} \]
  7. Taylor expanded in b around 0

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  8. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    3. lower-*.f6499.2

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  9. Simplified99.2%

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(c \cdot a\right)\right)} \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  10. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \frac{\color{blue}{\left(\left(3 \cdot c\right) \cdot a\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    2. lower-*.f64N/A

      \[\leadsto \frac{\color{blue}{\left(\left(3 \cdot c\right) \cdot a\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    3. lower-*.f6499.2

      \[\leadsto \frac{\left(\color{blue}{\left(3 \cdot c\right)} \cdot a\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  11. Applied egg-rr99.2%

    \[\leadsto \frac{\color{blue}{\left(\left(3 \cdot c\right) \cdot a\right)} \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  12. Add Preprocessing

Alternative 2: 86.0% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)\\ \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{t\_0 - b \cdot b}{\left(3 \cdot a\right) \cdot \left(b + \sqrt{t\_0}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (let* ((t_0 (fma a (* c -3.0) (* b b))))
   (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -0.02)
     (/ (- t_0 (* b b)) (* (* 3.0 a) (+ b (sqrt t_0))))
     (/ (fma a (* -0.375 (* c (/ c (* b b)))) (* c -0.5)) b))))
double code(double a, double b, double c) {
	double t_0 = fma(a, (c * -3.0), (b * b));
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -0.02) {
		tmp = (t_0 - (b * b)) / ((3.0 * a) * (b + sqrt(t_0)));
	} else {
		tmp = fma(a, (-0.375 * (c * (c / (b * b)))), (c * -0.5)) / b;
	}
	return tmp;
}
function code(a, b, c)
	t_0 = fma(a, Float64(c * -3.0), Float64(b * b))
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -0.02)
		tmp = Float64(Float64(t_0 - Float64(b * b)) / Float64(Float64(3.0 * a) * Float64(b + sqrt(t_0))));
	else
		tmp = Float64(fma(a, Float64(-0.375 * Float64(c * Float64(c / Float64(b * b)))), Float64(c * -0.5)) / b);
	end
	return tmp
end
code[a_, b_, c_] := Block[{t$95$0 = N[(a * N[(c * -3.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -0.02], N[(N[(t$95$0 - N[(b * b), $MachinePrecision]), $MachinePrecision] / N[(N[(3.0 * a), $MachinePrecision] * N[(b + N[Sqrt[t$95$0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[(-0.375 * N[(c * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(c * -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)\\
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\
\;\;\;\;\frac{t\_0 - b \cdot b}{\left(3 \cdot a\right) \cdot \left(b + \sqrt{t\_0}\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -0.0200000000000000004

    1. Initial program 82.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

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

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

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

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

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(\left(3 \cdot a\right) \cdot c\right)\right) + b \cdot b}}}{3 \cdot a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\left(\mathsf{neg}\left(\color{blue}{\left(3 \cdot a\right) \cdot c}\right)\right) + b \cdot b}}{3 \cdot a} \]
      7. distribute-lft-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(3 \cdot a\right)\right) \cdot c} + b \cdot b}}{3 \cdot a} \]
      8. lower-fma.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(3 \cdot a\right), c, b \cdot b\right)}}}{3 \cdot a} \]
      9. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{3 \cdot a}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      10. *-commutativeN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{a \cdot 3}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      11. distribute-rgt-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      13. metadata-eval83.0

        \[\leadsto \frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(a \cdot \color{blue}{-3}, c, b \cdot b\right)}}{3 \cdot a} \]
    4. Applied egg-rr83.0%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)}}}{3 \cdot a} \]
    5. Applied egg-rr84.4%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right) - b \cdot b}{\left(a \cdot 3\right) \cdot \left(b + \sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)}\right)}} \]

    if -0.0200000000000000004 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 47.7%

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

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
    5. Simplified88.7%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification87.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right) - b \cdot b}{\left(3 \cdot a\right) \cdot \left(b + \sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 85.6% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -0.02)
   (/ (- (sqrt (fma (* a -3.0) c (* b b))) b) (* 3.0 a))
   (/ (fma a (* -0.375 (* c (/ c (* b b)))) (* c -0.5)) b)))
double code(double a, double b, double c) {
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -0.02) {
		tmp = (sqrt(fma((a * -3.0), c, (b * b))) - b) / (3.0 * a);
	} else {
		tmp = fma(a, (-0.375 * (c * (c / (b * b)))), (c * -0.5)) / b;
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -0.02)
		tmp = Float64(Float64(sqrt(fma(Float64(a * -3.0), c, Float64(b * b))) - b) / Float64(3.0 * a));
	else
		tmp = Float64(fma(a, Float64(-0.375 * Float64(c * Float64(c / Float64(b * b)))), Float64(c * -0.5)) / b);
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -0.02], N[(N[(N[Sqrt[N[(N[(a * -3.0), $MachinePrecision] * c + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(a * N[(-0.375 * N[(c * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(c * -0.5), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -0.0200000000000000004

    1. Initial program 82.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

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

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

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

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

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(\left(3 \cdot a\right) \cdot c\right)\right) + b \cdot b}}}{3 \cdot a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\left(\mathsf{neg}\left(\color{blue}{\left(3 \cdot a\right) \cdot c}\right)\right) + b \cdot b}}{3 \cdot a} \]
      7. distribute-lft-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(3 \cdot a\right)\right) \cdot c} + b \cdot b}}{3 \cdot a} \]
      8. lower-fma.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(3 \cdot a\right), c, b \cdot b\right)}}}{3 \cdot a} \]
      9. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{3 \cdot a}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      10. *-commutativeN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{a \cdot 3}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      11. distribute-rgt-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      13. metadata-eval83.0

        \[\leadsto \frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(a \cdot \color{blue}{-3}, c, b \cdot b\right)}}{3 \cdot a} \]
    4. Applied egg-rr83.0%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)}}}{3 \cdot a} \]

    if -0.0200000000000000004 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 47.7%

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

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
    5. Simplified88.7%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification87.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a, -0.375 \cdot \left(c \cdot \frac{c}{b \cdot b}\right), c \cdot -0.5\right)}{b}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 85.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;c \cdot \mathsf{fma}\left(a, -0.375 \cdot \frac{c}{b \cdot \left(b \cdot b\right)}, \frac{-0.5}{b}\right)\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -0.02)
   (/ (- (sqrt (fma (* a -3.0) c (* b b))) b) (* 3.0 a))
   (* c (fma a (* -0.375 (/ c (* b (* b b)))) (/ -0.5 b)))))
double code(double a, double b, double c) {
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -0.02) {
		tmp = (sqrt(fma((a * -3.0), c, (b * b))) - b) / (3.0 * a);
	} else {
		tmp = c * fma(a, (-0.375 * (c / (b * (b * b)))), (-0.5 / b));
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -0.02)
		tmp = Float64(Float64(sqrt(fma(Float64(a * -3.0), c, Float64(b * b))) - b) / Float64(3.0 * a));
	else
		tmp = Float64(c * fma(a, Float64(-0.375 * Float64(c / Float64(b * Float64(b * b)))), Float64(-0.5 / b)));
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -0.02], N[(N[(N[Sqrt[N[(N[(a * -3.0), $MachinePrecision] * c + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(c * N[(a * N[(-0.375 * N[(c / N[(b * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\

\mathbf{else}:\\
\;\;\;\;c \cdot \mathsf{fma}\left(a, -0.375 \cdot \frac{c}{b \cdot \left(b \cdot b\right)}, \frac{-0.5}{b}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -0.0200000000000000004

    1. Initial program 82.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

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

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

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

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

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(\left(3 \cdot a\right) \cdot c\right)\right) + b \cdot b}}}{3 \cdot a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\left(\mathsf{neg}\left(\color{blue}{\left(3 \cdot a\right) \cdot c}\right)\right) + b \cdot b}}{3 \cdot a} \]
      7. distribute-lft-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(3 \cdot a\right)\right) \cdot c} + b \cdot b}}{3 \cdot a} \]
      8. lower-fma.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(3 \cdot a\right), c, b \cdot b\right)}}}{3 \cdot a} \]
      9. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{3 \cdot a}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      10. *-commutativeN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{a \cdot 3}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      11. distribute-rgt-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      13. metadata-eval83.0

        \[\leadsto \frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(a \cdot \color{blue}{-3}, c, b \cdot b\right)}}{3 \cdot a} \]
    4. Applied egg-rr83.0%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)}}}{3 \cdot a} \]

    if -0.0200000000000000004 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 47.7%

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

      \[\leadsto \color{blue}{c \cdot \left(\frac{-3}{8} \cdot \frac{a \cdot c}{{b}^{3}} - \frac{1}{2} \cdot \frac{1}{b}\right)} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto c \cdot \color{blue}{\left(\frac{-3}{8} \cdot \frac{a \cdot c}{{b}^{3}} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right)} \]
      2. distribute-rgt-inN/A

        \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot \frac{a \cdot c}{{b}^{3}}\right) \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right) \cdot c} \]
      3. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\frac{-3}{8} \cdot \left(a \cdot c\right)}{{b}^{3}}} \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right) \cdot c \]
      4. associate-*r*N/A

        \[\leadsto \frac{\color{blue}{\left(\frac{-3}{8} \cdot a\right) \cdot c}}{{b}^{3}} \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right) \cdot c \]
      5. associate-*l/N/A

        \[\leadsto \color{blue}{\left(\frac{\frac{-3}{8} \cdot a}{{b}^{3}} \cdot c\right)} \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right) \cdot c \]
      6. associate-*r/N/A

        \[\leadsto \left(\color{blue}{\left(\frac{-3}{8} \cdot \frac{a}{{b}^{3}}\right)} \cdot c\right) \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right) \cdot c \]
      7. distribute-rgt-inN/A

        \[\leadsto \color{blue}{c \cdot \left(\left(\frac{-3}{8} \cdot \frac{a}{{b}^{3}}\right) \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right)} \]
      8. lower-*.f64N/A

        \[\leadsto \color{blue}{c \cdot \left(\left(\frac{-3}{8} \cdot \frac{a}{{b}^{3}}\right) \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right)} \]
      9. associate-*r/N/A

        \[\leadsto c \cdot \left(\color{blue}{\frac{\frac{-3}{8} \cdot a}{{b}^{3}}} \cdot c + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      10. associate-*l/N/A

        \[\leadsto c \cdot \left(\color{blue}{\frac{\left(\frac{-3}{8} \cdot a\right) \cdot c}{{b}^{3}}} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      11. associate-*r*N/A

        \[\leadsto c \cdot \left(\frac{\color{blue}{\frac{-3}{8} \cdot \left(a \cdot c\right)}}{{b}^{3}} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      12. associate-*r/N/A

        \[\leadsto c \cdot \left(\color{blue}{\frac{-3}{8} \cdot \frac{a \cdot c}{{b}^{3}}} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      13. *-commutativeN/A

        \[\leadsto c \cdot \left(\color{blue}{\frac{a \cdot c}{{b}^{3}} \cdot \frac{-3}{8}} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      14. associate-/l*N/A

        \[\leadsto c \cdot \left(\color{blue}{\left(a \cdot \frac{c}{{b}^{3}}\right)} \cdot \frac{-3}{8} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
      15. associate-*l*N/A

        \[\leadsto c \cdot \left(\color{blue}{a \cdot \left(\frac{c}{{b}^{3}} \cdot \frac{-3}{8}\right)} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot \frac{1}{b}\right)\right)\right) \]
    5. Simplified88.6%

      \[\leadsto \color{blue}{c \cdot \mathsf{fma}\left(a, \frac{c}{b \cdot \left(b \cdot b\right)} \cdot -0.375, \frac{-0.5}{b}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification87.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -0.02:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;c \cdot \mathsf{fma}\left(a, -0.375 \cdot \frac{c}{b \cdot \left(b \cdot b\right)}, \frac{-0.5}{b}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 76.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -4e-6)
   (/ (- (sqrt (fma (* a -3.0) c (* b b))) b) (* 3.0 a))
   (/ (* c -0.5) b)))
double code(double a, double b, double c) {
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -4e-6) {
		tmp = (sqrt(fma((a * -3.0), c, (b * b))) - b) / (3.0 * a);
	} else {
		tmp = (c * -0.5) / b;
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -4e-6)
		tmp = Float64(Float64(sqrt(fma(Float64(a * -3.0), c, Float64(b * b))) - b) / Float64(3.0 * a));
	else
		tmp = Float64(Float64(c * -0.5) / b);
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -4e-6], N[(N[(N[Sqrt[N[(N[(a * -3.0), $MachinePrecision] * c + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\
\;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c \cdot -0.5}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -3.99999999999999982e-6

    1. Initial program 74.2%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

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

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

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

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

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(\left(3 \cdot a\right) \cdot c\right)\right) + b \cdot b}}}{3 \cdot a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\left(\mathsf{neg}\left(\color{blue}{\left(3 \cdot a\right) \cdot c}\right)\right) + b \cdot b}}{3 \cdot a} \]
      7. distribute-lft-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(3 \cdot a\right)\right) \cdot c} + b \cdot b}}{3 \cdot a} \]
      8. lower-fma.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(3 \cdot a\right), c, b \cdot b\right)}}}{3 \cdot a} \]
      9. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{3 \cdot a}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      10. *-commutativeN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{a \cdot 3}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      11. distribute-rgt-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      13. metadata-eval74.2

        \[\leadsto \frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(a \cdot \color{blue}{-3}, c, b \cdot b\right)}}{3 \cdot a} \]
    4. Applied egg-rr74.2%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)}}}{3 \cdot a} \]

    if -3.99999999999999982e-6 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 33.0%

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

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      2. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{c \cdot \frac{-1}{2}}}{b} \]
      4. lower-*.f6482.9

        \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
    5. Simplified82.9%

      \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)} - b}{3 \cdot a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 76.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{0.3333333333333333 \cdot \left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b\right)}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -4e-6)
   (/ (* 0.3333333333333333 (- (sqrt (fma a (* c -3.0) (* b b))) b)) a)
   (/ (* c -0.5) b)))
double code(double a, double b, double c) {
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -4e-6) {
		tmp = (0.3333333333333333 * (sqrt(fma(a, (c * -3.0), (b * b))) - b)) / a;
	} else {
		tmp = (c * -0.5) / b;
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -4e-6)
		tmp = Float64(Float64(0.3333333333333333 * Float64(sqrt(fma(a, Float64(c * -3.0), Float64(b * b))) - b)) / a);
	else
		tmp = Float64(Float64(c * -0.5) / b);
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -4e-6], N[(N[(0.3333333333333333 * N[(N[Sqrt[N[(a * N[(c * -3.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\
\;\;\;\;\frac{0.3333333333333333 \cdot \left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b\right)}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c \cdot -0.5}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -3.99999999999999982e-6

    1. Initial program 74.2%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

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

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

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

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

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(\left(3 \cdot a\right) \cdot c\right)\right) + b \cdot b}}}{3 \cdot a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\left(\mathsf{neg}\left(\color{blue}{\left(3 \cdot a\right) \cdot c}\right)\right) + b \cdot b}}{3 \cdot a} \]
      7. distribute-lft-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\left(\mathsf{neg}\left(3 \cdot a\right)\right) \cdot c} + b \cdot b}}{3 \cdot a} \]
      8. lower-fma.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(3 \cdot a\right), c, b \cdot b\right)}}}{3 \cdot a} \]
      9. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{3 \cdot a}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      10. *-commutativeN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{a \cdot 3}\right), c, b \cdot b\right)}}{3 \cdot a} \]
      11. distribute-rgt-neg-inN/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      12. lower-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\mathsf{fma}\left(\color{blue}{a \cdot \left(\mathsf{neg}\left(3\right)\right)}, c, b \cdot b\right)}}{3 \cdot a} \]
      13. metadata-eval74.2

        \[\leadsto \frac{\left(-b\right) + \sqrt{\mathsf{fma}\left(a \cdot \color{blue}{-3}, c, b \cdot b\right)}}{3 \cdot a} \]
    4. Applied egg-rr74.2%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\mathsf{fma}\left(a \cdot -3, c, b \cdot b\right)}}}{3 \cdot a} \]
    5. Applied egg-rr74.2%

      \[\leadsto \color{blue}{\frac{\left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b\right) \cdot 0.3333333333333333}{a}} \]

    if -3.99999999999999982e-6 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 33.0%

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

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      2. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{c \cdot \frac{-1}{2}}}{b} \]
      4. lower-*.f6482.9

        \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
    5. Simplified82.9%

      \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{0.3333333333333333 \cdot \left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b\right)}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 76.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{-0.3333333333333333}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (if (<= (/ (- (sqrt (- (* b b) (* c (* 3.0 a)))) b) (* 3.0 a)) -4e-6)
   (* (/ -0.3333333333333333 a) (- b (sqrt (fma a (* c -3.0) (* b b)))))
   (/ (* c -0.5) b)))
double code(double a, double b, double c) {
	double tmp;
	if (((sqrt(((b * b) - (c * (3.0 * a)))) - b) / (3.0 * a)) <= -4e-6) {
		tmp = (-0.3333333333333333 / a) * (b - sqrt(fma(a, (c * -3.0), (b * b))));
	} else {
		tmp = (c * -0.5) / b;
	}
	return tmp;
}
function code(a, b, c)
	tmp = 0.0
	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(3.0 * a)))) - b) / Float64(3.0 * a)) <= -4e-6)
		tmp = Float64(Float64(-0.3333333333333333 / a) * Float64(b - sqrt(fma(a, Float64(c * -3.0), Float64(b * b)))));
	else
		tmp = Float64(Float64(c * -0.5) / b);
	end
	return tmp
end
code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(3.0 * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision], -4e-6], N[(N[(-0.3333333333333333 / a), $MachinePrecision] * N[(b - N[Sqrt[N[(a * N[(c * -3.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\
\;\;\;\;\frac{-0.3333333333333333}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{c \cdot -0.5}{b}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a)) < -3.99999999999999982e-6

    1. Initial program 74.2%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Applied egg-rr74.2%

      \[\leadsto \color{blue}{\frac{-0.3333333333333333}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(a, -3 \cdot c, b \cdot b\right)}\right)} \]

    if -3.99999999999999982e-6 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 #s(literal 3 binary64) a) c)))) (*.f64 #s(literal 3 binary64) a))

    1. Initial program 33.0%

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

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      2. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{c \cdot \frac{-1}{2}}}{b} \]
      4. lower-*.f6482.9

        \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
    5. Simplified82.9%

      \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(3 \cdot a\right)} - b}{3 \cdot a} \leq -4 \cdot 10^{-6}:\\ \;\;\;\;\frac{-0.3333333333333333}{a} \cdot \left(b - \sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{c \cdot -0.5}{b}\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 99.1% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  (* (/ 0.3333333333333333 a) (* 3.0 (* c a)))
  (- (- b) (sqrt (* c (fma a -3.0 (/ (* b b) c)))))))
double code(double a, double b, double c) {
	return ((0.3333333333333333 / a) * (3.0 * (c * a))) / (-b - sqrt((c * fma(a, -3.0, ((b * b) / c)))));
}
function code(a, b, c)
	return Float64(Float64(Float64(0.3333333333333333 / a) * Float64(3.0 * Float64(c * a))) / Float64(Float64(-b) - sqrt(Float64(c * fma(a, -3.0, Float64(Float64(b * b) / c))))))
end
code[a_, b_, c_] := N[(N[(N[(0.3333333333333333 / a), $MachinePrecision] * N[(3.0 * N[(c * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(c * N[(a * -3.0 + N[(N[(b * b), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}}
\end{array}
Derivation
  1. Initial program 57.6%

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

    \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
  4. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
    2. cancel-sign-sub-invN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\left(\frac{{b}^{2}}{c} + \left(\mathsf{neg}\left(3\right)\right) \cdot a\right)}}}{3 \cdot a} \]
    3. metadata-evalN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{{b}^{2}}{c} + \color{blue}{-3} \cdot a\right)}}{3 \cdot a} \]
    4. unpow2N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{\color{blue}{b \cdot b}}{c} + -3 \cdot a\right)}}{3 \cdot a} \]
    5. associate-/l*N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\color{blue}{b \cdot \frac{b}{c}} + -3 \cdot a\right)}}{3 \cdot a} \]
    6. lower-fma.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\mathsf{fma}\left(b, \frac{b}{c}, -3 \cdot a\right)}}}{3 \cdot a} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \color{blue}{\frac{b}{c}}, -3 \cdot a\right)}}{3 \cdot a} \]
    8. *-commutativeN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
    9. lower-*.f6457.3

      \[\leadsto \frac{\left(-b\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
  5. Simplified57.3%

    \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, a \cdot -3\right)}}}{3 \cdot a} \]
  6. Applied egg-rr58.1%

    \[\leadsto \color{blue}{\frac{\left(b \cdot b - c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}}} \]
  7. Taylor expanded in b around 0

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  8. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    3. lower-*.f6499.2

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  9. Simplified99.2%

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(c \cdot a\right)\right)} \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  10. Final simplification99.2%

    \[\leadsto \frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  11. Add Preprocessing

Alternative 9: 99.1% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, b \cdot \frac{b}{c}\right)}} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  (* (/ 0.3333333333333333 a) (* 3.0 (* c a)))
  (- (- b) (sqrt (* c (fma a -3.0 (* b (/ b c))))))))
double code(double a, double b, double c) {
	return ((0.3333333333333333 / a) * (3.0 * (c * a))) / (-b - sqrt((c * fma(a, -3.0, (b * (b / c))))));
}
function code(a, b, c)
	return Float64(Float64(Float64(0.3333333333333333 / a) * Float64(3.0 * Float64(c * a))) / Float64(Float64(-b) - sqrt(Float64(c * fma(a, -3.0, Float64(b * Float64(b / c)))))))
end
code[a_, b_, c_] := N[(N[(N[(0.3333333333333333 / a), $MachinePrecision] * N[(3.0 * N[(c * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(c * N[(a * -3.0 + N[(b * N[(b / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, b \cdot \frac{b}{c}\right)}}
\end{array}
Derivation
  1. Initial program 57.6%

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

    \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
  4. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{\color{blue}{c \cdot \left(\frac{{b}^{2}}{c} - 3 \cdot a\right)}}}{3 \cdot a} \]
    2. cancel-sign-sub-invN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\left(\frac{{b}^{2}}{c} + \left(\mathsf{neg}\left(3\right)\right) \cdot a\right)}}}{3 \cdot a} \]
    3. metadata-evalN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{{b}^{2}}{c} + \color{blue}{-3} \cdot a\right)}}{3 \cdot a} \]
    4. unpow2N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\frac{\color{blue}{b \cdot b}}{c} + -3 \cdot a\right)}}{3 \cdot a} \]
    5. associate-/l*N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \left(\color{blue}{b \cdot \frac{b}{c}} + -3 \cdot a\right)}}{3 \cdot a} \]
    6. lower-fma.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \color{blue}{\mathsf{fma}\left(b, \frac{b}{c}, -3 \cdot a\right)}}}{3 \cdot a} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \color{blue}{\frac{b}{c}}, -3 \cdot a\right)}}{3 \cdot a} \]
    8. *-commutativeN/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(b\right)\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
    9. lower-*.f6457.3

      \[\leadsto \frac{\left(-b\right) + \sqrt{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, \color{blue}{a \cdot -3}\right)}}{3 \cdot a} \]
  5. Simplified57.3%

    \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{c \cdot \mathsf{fma}\left(b, \frac{b}{c}, a \cdot -3\right)}}}{3 \cdot a} \]
  6. Applied egg-rr58.1%

    \[\leadsto \color{blue}{\frac{\left(b \cdot b - c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}}} \]
  7. Taylor expanded in b around 0

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  8. Step-by-step derivation
    1. lower-*.f64N/A

      \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(a \cdot c\right)\right)} \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    2. *-commutativeN/A

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
    3. lower-*.f6499.2

      \[\leadsto \frac{\left(3 \cdot \color{blue}{\left(c \cdot a\right)}\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  9. Simplified99.2%

    \[\leadsto \frac{\color{blue}{\left(3 \cdot \left(c \cdot a\right)\right)} \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \frac{b \cdot b}{c}\right)}} \]
  10. Step-by-step derivation
    1. associate-*l/N/A

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

      \[\leadsto \frac{\left(3 \cdot \left(c \cdot a\right)\right) \cdot \frac{\frac{1}{3}}{a}}{\left(\mathsf{neg}\left(b\right)\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \color{blue}{\frac{b}{c}} \cdot b\right)}} \]
    3. lower-*.f6499.2

      \[\leadsto \frac{\left(3 \cdot \left(c \cdot a\right)\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \color{blue}{\frac{b}{c} \cdot b}\right)}} \]
  11. Applied egg-rr99.2%

    \[\leadsto \frac{\left(3 \cdot \left(c \cdot a\right)\right) \cdot \frac{0.3333333333333333}{a}}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, \color{blue}{\frac{b}{c} \cdot b}\right)}} \]
  12. Final simplification99.2%

    \[\leadsto \frac{\frac{0.3333333333333333}{a} \cdot \left(3 \cdot \left(c \cdot a\right)\right)}{\left(-b\right) - \sqrt{c \cdot \mathsf{fma}\left(a, -3, b \cdot \frac{b}{c}\right)}} \]
  13. Add Preprocessing

Alternative 10: 64.8% accurate, 2.9× speedup?

\[\begin{array}{l} \\ \frac{c \cdot -0.5}{b} \end{array} \]
(FPCore (a b c) :precision binary64 (/ (* c -0.5) b))
double code(double a, double b, double c) {
	return (c * -0.5) / 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 * (-0.5d0)) / b
end function
public static double code(double a, double b, double c) {
	return (c * -0.5) / b;
}
def code(a, b, c):
	return (c * -0.5) / b
function code(a, b, c)
	return Float64(Float64(c * -0.5) / b)
end
function tmp = code(a, b, c)
	tmp = (c * -0.5) / b;
end
code[a_, b_, c_] := N[(N[(c * -0.5), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}

\\
\frac{c \cdot -0.5}{b}
\end{array}
Derivation
  1. Initial program 57.6%

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

    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
  4. Step-by-step derivation
    1. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
    2. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\color{blue}{c \cdot \frac{-1}{2}}}{b} \]
    4. lower-*.f6462.6

      \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
  5. Simplified62.6%

    \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
  6. Add Preprocessing

Alternative 11: 64.7% accurate, 2.9× speedup?

\[\begin{array}{l} \\ c \cdot \frac{-0.5}{b} \end{array} \]
(FPCore (a b c) :precision binary64 (* c (/ -0.5 b)))
double code(double a, double b, double c) {
	return c * (-0.5 / 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 * ((-0.5d0) / b)
end function
public static double code(double a, double b, double c) {
	return c * (-0.5 / b);
}
def code(a, b, c):
	return c * (-0.5 / b)
function code(a, b, c)
	return Float64(c * Float64(-0.5 / b))
end
function tmp = code(a, b, c)
	tmp = c * (-0.5 / b);
end
code[a_, b_, c_] := N[(c * N[(-0.5 / b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
c \cdot \frac{-0.5}{b}
\end{array}
Derivation
  1. Initial program 57.6%

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

    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
  4. Step-by-step derivation
    1. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
    2. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c}{b}} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\color{blue}{c \cdot \frac{-1}{2}}}{b} \]
    4. lower-*.f6462.6

      \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
  5. Simplified62.6%

    \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
  6. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{\color{blue}{\frac{-1}{2} \cdot c}}{b} \]
    2. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2}}{b} \cdot c} \]
    3. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{-1}{2}}{b}} \cdot c \]
    4. lower-*.f6462.5

      \[\leadsto \color{blue}{\frac{-0.5}{b} \cdot c} \]
  7. Applied egg-rr62.5%

    \[\leadsto \color{blue}{\frac{-0.5}{b} \cdot c} \]
  8. Final simplification62.5%

    \[\leadsto c \cdot \frac{-0.5}{b} \]
  9. Add Preprocessing

Alternative 12: 3.2% accurate, 50.0× speedup?

\[\begin{array}{l} \\ 0 \end{array} \]
(FPCore (a b c) :precision binary64 0.0)
double code(double a, double b, double c) {
	return 0.0;
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = 0.0d0
end function
public static double code(double a, double b, double c) {
	return 0.0;
}
def code(a, b, c):
	return 0.0
function code(a, b, c)
	return 0.0
end
function tmp = code(a, b, c)
	tmp = 0.0;
end
code[a_, b_, c_] := 0.0
\begin{array}{l}

\\
0
\end{array}
Derivation
  1. Initial program 57.6%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Applied egg-rr57.3%

    \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\frac{\sqrt{\mathsf{fma}\left(a, -3 \cdot c, b \cdot b\right)} \cdot \sqrt{\mathsf{fma}\left(-9, a \cdot \left(c \cdot \left(a \cdot c\right)\right), b \cdot \left(b \cdot \left(b \cdot b\right)\right)\right)}}{\sqrt{\mathsf{fma}\left(3, a \cdot c, b \cdot b\right)}}}}}{3 \cdot a} \]
  4. Taylor expanded in b around inf

    \[\leadsto \color{blue}{0} \]
  5. Step-by-step derivation
    1. Simplified3.2%

      \[\leadsto \color{blue}{0} \]
    2. Add Preprocessing

    Reproduce

    ?
    herbie shell --seed 2024215 
    (FPCore (a b c)
      :name "Cubic critical, narrow range"
      :precision binary64
      :pre (and (and (and (< 1.0536712127723509e-8 a) (< a 94906265.62425156)) (and (< 1.0536712127723509e-8 b) (< b 94906265.62425156))) (and (< 1.0536712127723509e-8 c) (< c 94906265.62425156)))
      (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))