Cubic critical, wide range

Percentage Accurate: 18.0% → 99.4%
Time: 16.4s
Alternatives: 7
Speedup: 23.2×

Specification

?
\[\left(\left(4.930380657631324 \cdot 10^{-32} < a \land a < 2.028240960365167 \cdot 10^{+31}\right) \land \left(4.930380657631324 \cdot 10^{-32} < b \land b < 2.028240960365167 \cdot 10^{+31}\right)\right) \land \left(4.930380657631324 \cdot 10^{-32} < c \land c < 2.028240960365167 \cdot 10^{+31}\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(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 7 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: 18.0% 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: 99.4% accurate, 0.5× speedup?

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

\\
\frac{\frac{c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot \left(-3\right)\right)\right)}}}{a \cdot 3}
\end{array}
Derivation
  1. Initial program 16.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. expm1-log1p-u16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
    2. expm1-undefine12.9%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  4. Applied egg-rr12.9%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  5. Step-by-step derivation
    1. expm1-define16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  6. Simplified16.1%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  7. Step-by-step derivation
    1. flip-+16.1%

      \[\leadsto \frac{\color{blue}{\frac{\left(-b\right) \cdot \left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}}{3 \cdot a} \]
    2. pow216.1%

      \[\leadsto \frac{\frac{\color{blue}{{\left(-b\right)}^{2}} - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    3. add-sqr-sqrt16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \color{blue}{\left(b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    4. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left(\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    5. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    6. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    7. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    8. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    9. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c}}}{3 \cdot a} \]
    10. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}}}}{3 \cdot a} \]
    11. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}}}}{3 \cdot a} \]
  8. Applied egg-rr16.7%

    \[\leadsto \frac{\color{blue}{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  9. Step-by-step derivation
    1. associate--r-99.5%

      \[\leadsto \frac{\frac{\color{blue}{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  10. Simplified99.5%

    \[\leadsto \frac{\color{blue}{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  11. Step-by-step derivation
    1. *-commutative99.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \color{blue}{\left(3 \cdot a\right)}}}}{3 \cdot a} \]
    2. *-commutative99.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{\left(3 \cdot a\right) \cdot c}}}}{3 \cdot a} \]
    3. cancel-sign-sub-inv99.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\color{blue}{{b}^{2} + \left(-3 \cdot a\right) \cdot c}}}}{3 \cdot a} \]
    4. pow299.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\color{blue}{b \cdot b} + \left(-3 \cdot a\right) \cdot c}}}{3 \cdot a} \]
    5. fma-define99.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\color{blue}{\mathsf{fma}\left(b, b, \left(-3 \cdot a\right) \cdot c\right)}}}}{3 \cdot a} \]
    6. *-commutative99.5%

      \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, \left(-\color{blue}{a \cdot 3}\right) \cdot c\right)}}}{3 \cdot a} \]
  12. Applied egg-rr99.5%

    \[\leadsto \frac{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\color{blue}{\mathsf{fma}\left(b, b, \left(-a \cdot 3\right) \cdot c\right)}}}}{3 \cdot a} \]
  13. Taylor expanded in b around 0 99.5%

    \[\leadsto \frac{\frac{\color{blue}{0} + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{\mathsf{fma}\left(b, b, \left(-a \cdot 3\right) \cdot c\right)}}}{3 \cdot a} \]
  14. Final simplification99.5%

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

Alternative 2: 99.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := c \cdot \left(a \cdot 3\right)\\ \frac{\frac{t\_0}{\left(-b\right) - \sqrt{{b}^{2} - t\_0}}}{a \cdot 3} \end{array} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (let* ((t_0 (* c (* a 3.0))))
   (/ (/ t_0 (- (- b) (sqrt (- (pow b 2.0) t_0)))) (* a 3.0))))
double code(double a, double b, double c) {
	double t_0 = c * (a * 3.0);
	return (t_0 / (-b - sqrt((pow(b, 2.0) - t_0)))) / (a * 3.0);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8) :: t_0
    t_0 = c * (a * 3.0d0)
    code = (t_0 / (-b - sqrt(((b ** 2.0d0) - t_0)))) / (a * 3.0d0)
end function
public static double code(double a, double b, double c) {
	double t_0 = c * (a * 3.0);
	return (t_0 / (-b - Math.sqrt((Math.pow(b, 2.0) - t_0)))) / (a * 3.0);
}
def code(a, b, c):
	t_0 = c * (a * 3.0)
	return (t_0 / (-b - math.sqrt((math.pow(b, 2.0) - t_0)))) / (a * 3.0)
function code(a, b, c)
	t_0 = Float64(c * Float64(a * 3.0))
	return Float64(Float64(t_0 / Float64(Float64(-b) - sqrt(Float64((b ^ 2.0) - t_0)))) / Float64(a * 3.0))
end
function tmp = code(a, b, c)
	t_0 = c * (a * 3.0);
	tmp = (t_0 / (-b - sqrt(((b ^ 2.0) - t_0)))) / (a * 3.0);
end
code[a_, b_, c_] := Block[{t$95$0 = N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$0 / N[((-b) - N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := c \cdot \left(a \cdot 3\right)\\
\frac{\frac{t\_0}{\left(-b\right) - \sqrt{{b}^{2} - t\_0}}}{a \cdot 3}
\end{array}
\end{array}
Derivation
  1. Initial program 16.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. expm1-log1p-u16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
    2. expm1-undefine12.9%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  4. Applied egg-rr12.9%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  5. Step-by-step derivation
    1. expm1-define16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  6. Simplified16.1%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  7. Step-by-step derivation
    1. flip-+16.1%

      \[\leadsto \frac{\color{blue}{\frac{\left(-b\right) \cdot \left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}}{3 \cdot a} \]
    2. pow216.1%

      \[\leadsto \frac{\frac{\color{blue}{{\left(-b\right)}^{2}} - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    3. add-sqr-sqrt16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \color{blue}{\left(b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    4. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left(\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    5. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    6. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    7. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    8. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    9. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c}}}{3 \cdot a} \]
    10. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}}}}{3 \cdot a} \]
    11. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}}}}{3 \cdot a} \]
  8. Applied egg-rr16.7%

    \[\leadsto \frac{\color{blue}{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  9. Step-by-step derivation
    1. associate--r-99.5%

      \[\leadsto \frac{\frac{\color{blue}{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  10. Simplified99.5%

    \[\leadsto \frac{\color{blue}{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  11. Taylor expanded in b around 0 99.5%

    \[\leadsto \frac{\frac{\color{blue}{0} + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  12. Step-by-step derivation
    1. +-lft-identity99.5%

      \[\leadsto \frac{\frac{\color{blue}{c \cdot \left(a \cdot 3\right)}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
    2. *-commutative99.5%

      \[\leadsto \frac{\frac{c \cdot \color{blue}{\left(3 \cdot a\right)}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
    3. *-commutative99.5%

      \[\leadsto \frac{\frac{\color{blue}{\left(3 \cdot a\right) \cdot c}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
    4. *-commutative99.5%

      \[\leadsto \frac{\frac{\color{blue}{\left(a \cdot 3\right)} \cdot c}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  13. Applied egg-rr99.5%

    \[\leadsto \frac{\frac{\color{blue}{\left(a \cdot 3\right) \cdot c}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  14. Final simplification99.5%

    \[\leadsto \frac{\frac{c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3} \]
  15. Add Preprocessing

Alternative 3: 99.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \frac{\frac{3 \cdot \left(c \cdot a\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  (/ (* 3.0 (* c a)) (- (- b) (sqrt (- (pow b 2.0) (* c (* a 3.0))))))
  (* a 3.0)))
double code(double a, double b, double c) {
	return ((3.0 * (c * a)) / (-b - sqrt((pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = ((3.0d0 * (c * a)) / (-b - sqrt(((b ** 2.0d0) - (c * (a * 3.0d0)))))) / (a * 3.0d0)
end function
public static double code(double a, double b, double c) {
	return ((3.0 * (c * a)) / (-b - Math.sqrt((Math.pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0);
}
def code(a, b, c):
	return ((3.0 * (c * a)) / (-b - math.sqrt((math.pow(b, 2.0) - (c * (a * 3.0)))))) / (a * 3.0)
function code(a, b, c)
	return Float64(Float64(Float64(3.0 * Float64(c * a)) / Float64(Float64(-b) - sqrt(Float64((b ^ 2.0) - Float64(c * Float64(a * 3.0)))))) / Float64(a * 3.0))
end
function tmp = code(a, b, c)
	tmp = ((3.0 * (c * a)) / (-b - sqrt(((b ^ 2.0) - (c * (a * 3.0)))))) / (a * 3.0);
end
code[a_, b_, c_] := N[(N[(N[(3.0 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[((-b) - N[Sqrt[N[(N[Power[b, 2.0], $MachinePrecision] - N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{3 \cdot \left(c \cdot a\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3}
\end{array}
Derivation
  1. Initial program 16.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. expm1-log1p-u16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
    2. expm1-undefine12.9%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  4. Applied egg-rr12.9%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  5. Step-by-step derivation
    1. expm1-define16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  6. Simplified16.1%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  7. Step-by-step derivation
    1. flip-+16.1%

      \[\leadsto \frac{\color{blue}{\frac{\left(-b\right) \cdot \left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}}{3 \cdot a} \]
    2. pow216.1%

      \[\leadsto \frac{\frac{\color{blue}{{\left(-b\right)}^{2}} - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c} \cdot \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    3. add-sqr-sqrt16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \color{blue}{\left(b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    4. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left(\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    5. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    6. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    7. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}\right)}{\left(-b\right) - \sqrt{b \cdot b - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    8. pow216.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{\color{blue}{{b}^{2}} - \mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right) \cdot c}}}{3 \cdot a} \]
    9. expm1-log1p-u16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{\left(3 \cdot a\right)} \cdot c}}}{3 \cdot a} \]
    10. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - \color{blue}{c \cdot \left(3 \cdot a\right)}}}}{3 \cdot a} \]
    11. *-commutative16.7%

      \[\leadsto \frac{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \color{blue}{\left(a \cdot 3\right)}}}}{3 \cdot a} \]
  8. Applied egg-rr16.7%

    \[\leadsto \frac{\color{blue}{\frac{{\left(-b\right)}^{2} - \left({b}^{2} - c \cdot \left(a \cdot 3\right)\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  9. Step-by-step derivation
    1. associate--r-99.5%

      \[\leadsto \frac{\frac{\color{blue}{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{3 \cdot a} \]
  10. Simplified99.5%

    \[\leadsto \frac{\color{blue}{\frac{\left({\left(-b\right)}^{2} - {b}^{2}\right) + c \cdot \left(a \cdot 3\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}}{3 \cdot a} \]
  11. Taylor expanded in b around 0 99.2%

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

    \[\leadsto \frac{\frac{3 \cdot \left(c \cdot a\right)}{\left(-b\right) - \sqrt{{b}^{2} - c \cdot \left(a \cdot 3\right)}}}{a \cdot 3} \]
  13. Add Preprocessing

Alternative 4: 95.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot {\left(\frac{c}{b}\right)}^{2}\right)\right)}{b} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (fma -0.5 c (* -0.375 (* a (pow (/ c b) 2.0)))) b))
double code(double a, double b, double c) {
	return fma(-0.5, c, (-0.375 * (a * pow((c / b), 2.0)))) / b;
}
function code(a, b, c)
	return Float64(fma(-0.5, c, Float64(-0.375 * Float64(a * (Float64(c / b) ^ 2.0)))) / b)
end
code[a_, b_, c_] := N[(N[(-0.5 * c + N[(-0.375 * N[(a * N[Power[N[(c / b), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
\begin{array}{l}

\\
\frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot {\left(\frac{c}{b}\right)}^{2}\right)\right)}{b}
\end{array}
Derivation
  1. Initial program 16.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. expm1-log1p-u16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
    2. expm1-undefine12.9%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  4. Applied egg-rr12.9%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(e^{\mathsf{log1p}\left(3 \cdot a\right)} - 1\right)} \cdot c}}{3 \cdot a} \]
  5. Step-by-step derivation
    1. expm1-define16.1%

      \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  6. Simplified16.1%

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(3 \cdot a\right)\right)} \cdot c}}{3 \cdot a} \]
  7. Taylor expanded in b around inf 96.4%

    \[\leadsto \color{blue}{\frac{-0.5 \cdot c + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
  8. Step-by-step derivation
    1. fma-define96.4%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}}{b} \]
    2. associate-/l*96.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \color{blue}{\left(a \cdot \frac{{c}^{2}}{{b}^{2}}\right)}\right)}{b} \]
    3. unpow296.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot \frac{\color{blue}{c \cdot c}}{{b}^{2}}\right)\right)}{b} \]
    4. unpow296.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot \frac{c \cdot c}{\color{blue}{b \cdot b}}\right)\right)}{b} \]
    5. times-frac96.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot \color{blue}{\left(\frac{c}{b} \cdot \frac{c}{b}\right)}\right)\right)}{b} \]
    6. unpow196.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot \left(\color{blue}{{\left(\frac{c}{b}\right)}^{1}} \cdot \frac{c}{b}\right)\right)\right)}{b} \]
    7. pow-plus96.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot \color{blue}{{\left(\frac{c}{b}\right)}^{\left(1 + 1\right)}}\right)\right)}{b} \]
    8. metadata-eval96.4%

      \[\leadsto \frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot {\left(\frac{c}{b}\right)}^{\color{blue}{2}}\right)\right)}{b} \]
  9. Simplified96.4%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(-0.5, c, -0.375 \cdot \left(a \cdot {\left(\frac{c}{b}\right)}^{2}\right)\right)}{b}} \]
  10. Add Preprocessing

Alternative 5: 95.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ c \cdot \frac{1}{b \cdot \left(1.5 \cdot \frac{c \cdot a}{{b}^{2}} - 2\right)} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (* c (/ 1.0 (* b (- (* 1.5 (/ (* c a) (pow b 2.0))) 2.0)))))
double code(double a, double b, double c) {
	return c * (1.0 / (b * ((1.5 * ((c * a) / pow(b, 2.0))) - 2.0)));
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = c * (1.0d0 / (b * ((1.5d0 * ((c * a) / (b ** 2.0d0))) - 2.0d0)))
end function
public static double code(double a, double b, double c) {
	return c * (1.0 / (b * ((1.5 * ((c * a) / Math.pow(b, 2.0))) - 2.0)));
}
def code(a, b, c):
	return c * (1.0 / (b * ((1.5 * ((c * a) / math.pow(b, 2.0))) - 2.0)))
function code(a, b, c)
	return Float64(c * Float64(1.0 / Float64(b * Float64(Float64(1.5 * Float64(Float64(c * a) / (b ^ 2.0))) - 2.0))))
end
function tmp = code(a, b, c)
	tmp = c * (1.0 / (b * ((1.5 * ((c * a) / (b ^ 2.0))) - 2.0)));
end
code[a_, b_, c_] := N[(c * N[(1.0 / N[(b * N[(N[(1.5 * N[(N[(c * a), $MachinePrecision] / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
c \cdot \frac{1}{b \cdot \left(1.5 \cdot \frac{c \cdot a}{{b}^{2}} - 2\right)}
\end{array}
Derivation
  1. Initial program 16.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Step-by-step derivation
    1. Simplified16.1%

      \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -3\right)\right)} - b}{3 \cdot a}} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0 96.0%

      \[\leadsto \color{blue}{c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - 0.5 \cdot \frac{1}{b}\right)} \]
    4. Step-by-step derivation
      1. associate-*r/96.0%

        \[\leadsto c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \color{blue}{\frac{0.5 \cdot 1}{b}}\right) \]
      2. metadata-eval96.0%

        \[\leadsto c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \frac{\color{blue}{0.5}}{b}\right) \]
    5. Simplified96.0%

      \[\leadsto \color{blue}{c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \frac{0.5}{b}\right)} \]
    6. Taylor expanded in b around inf 95.9%

      \[\leadsto c \cdot \color{blue}{\frac{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}{b}} \]
    7. Step-by-step derivation
      1. clear-num95.9%

        \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}}} \]
      2. inv-pow95.9%

        \[\leadsto c \cdot \color{blue}{{\left(\frac{b}{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}\right)}^{-1}} \]
      3. fmm-def95.9%

        \[\leadsto c \cdot {\left(\frac{b}{\color{blue}{\mathsf{fma}\left(-0.375, \frac{a \cdot c}{{b}^{2}}, -0.5\right)}}\right)}^{-1} \]
      4. associate-/l*95.9%

        \[\leadsto c \cdot {\left(\frac{b}{\mathsf{fma}\left(-0.375, \color{blue}{a \cdot \frac{c}{{b}^{2}}}, -0.5\right)}\right)}^{-1} \]
      5. metadata-eval95.9%

        \[\leadsto c \cdot {\left(\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, \color{blue}{-0.5}\right)}\right)}^{-1} \]
    8. Applied egg-rr95.9%

      \[\leadsto c \cdot \color{blue}{{\left(\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}\right)}^{-1}} \]
    9. Step-by-step derivation
      1. unpow-195.9%

        \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}}} \]
    10. Simplified95.9%

      \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}}} \]
    11. Taylor expanded in b around inf 96.1%

      \[\leadsto c \cdot \frac{1}{\color{blue}{b \cdot \left(1.5 \cdot \frac{a \cdot c}{{b}^{2}} - 2\right)}} \]
    12. Final simplification96.1%

      \[\leadsto c \cdot \frac{1}{b \cdot \left(1.5 \cdot \frac{c \cdot a}{{b}^{2}} - 2\right)} \]
    13. Add Preprocessing

    Alternative 6: 95.0% accurate, 7.7× speedup?

    \[\begin{array}{l} \\ c \cdot \frac{1}{b \cdot -2 + 1.5 \cdot \frac{c \cdot a}{b}} \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (* c (/ 1.0 (+ (* b -2.0) (* 1.5 (/ (* c a) b))))))
    double code(double a, double b, double c) {
    	return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / 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 * (1.0d0 / ((b * (-2.0d0)) + (1.5d0 * ((c * a) / b))))
    end function
    
    public static double code(double a, double b, double c) {
    	return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b))));
    }
    
    def code(a, b, c):
    	return c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b))))
    
    function code(a, b, c)
    	return Float64(c * Float64(1.0 / Float64(Float64(b * -2.0) + Float64(1.5 * Float64(Float64(c * a) / b)))))
    end
    
    function tmp = code(a, b, c)
    	tmp = c * (1.0 / ((b * -2.0) + (1.5 * ((c * a) / b))));
    end
    
    code[a_, b_, c_] := N[(c * N[(1.0 / N[(N[(b * -2.0), $MachinePrecision] + N[(1.5 * N[(N[(c * a), $MachinePrecision] / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    c \cdot \frac{1}{b \cdot -2 + 1.5 \cdot \frac{c \cdot a}{b}}
    \end{array}
    
    Derivation
    1. Initial program 16.1%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Step-by-step derivation
      1. Simplified16.1%

        \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -3\right)\right)} - b}{3 \cdot a}} \]
      2. Add Preprocessing
      3. Taylor expanded in c around 0 96.0%

        \[\leadsto \color{blue}{c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - 0.5 \cdot \frac{1}{b}\right)} \]
      4. Step-by-step derivation
        1. associate-*r/96.0%

          \[\leadsto c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \color{blue}{\frac{0.5 \cdot 1}{b}}\right) \]
        2. metadata-eval96.0%

          \[\leadsto c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \frac{\color{blue}{0.5}}{b}\right) \]
      5. Simplified96.0%

        \[\leadsto \color{blue}{c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - \frac{0.5}{b}\right)} \]
      6. Taylor expanded in b around inf 95.9%

        \[\leadsto c \cdot \color{blue}{\frac{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}{b}} \]
      7. Step-by-step derivation
        1. clear-num95.9%

          \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}}} \]
        2. inv-pow95.9%

          \[\leadsto c \cdot \color{blue}{{\left(\frac{b}{-0.375 \cdot \frac{a \cdot c}{{b}^{2}} - 0.5}\right)}^{-1}} \]
        3. fmm-def95.9%

          \[\leadsto c \cdot {\left(\frac{b}{\color{blue}{\mathsf{fma}\left(-0.375, \frac{a \cdot c}{{b}^{2}}, -0.5\right)}}\right)}^{-1} \]
        4. associate-/l*95.9%

          \[\leadsto c \cdot {\left(\frac{b}{\mathsf{fma}\left(-0.375, \color{blue}{a \cdot \frac{c}{{b}^{2}}}, -0.5\right)}\right)}^{-1} \]
        5. metadata-eval95.9%

          \[\leadsto c \cdot {\left(\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, \color{blue}{-0.5}\right)}\right)}^{-1} \]
      8. Applied egg-rr95.9%

        \[\leadsto c \cdot \color{blue}{{\left(\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}\right)}^{-1}} \]
      9. Step-by-step derivation
        1. unpow-195.9%

          \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}}} \]
      10. Simplified95.9%

        \[\leadsto c \cdot \color{blue}{\frac{1}{\frac{b}{\mathsf{fma}\left(-0.375, a \cdot \frac{c}{{b}^{2}}, -0.5\right)}}} \]
      11. Taylor expanded in a around 0 96.1%

        \[\leadsto c \cdot \frac{1}{\color{blue}{-2 \cdot b + 1.5 \cdot \frac{a \cdot c}{b}}} \]
      12. Final simplification96.1%

        \[\leadsto c \cdot \frac{1}{b \cdot -2 + 1.5 \cdot \frac{c \cdot a}{b}} \]
      13. Add Preprocessing

      Alternative 7: 90.2% accurate, 23.2× speedup?

      \[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b} \end{array} \]
      (FPCore (a b c) :precision binary64 (* -0.5 (/ c b)))
      double code(double a, double b, double c) {
      	return -0.5 * (c / b);
      }
      
      real(8) function code(a, b, c)
          real(8), intent (in) :: a
          real(8), intent (in) :: b
          real(8), intent (in) :: c
          code = (-0.5d0) * (c / b)
      end function
      
      public static double code(double a, double b, double c) {
      	return -0.5 * (c / b);
      }
      
      def code(a, b, c):
      	return -0.5 * (c / b)
      
      function code(a, b, c)
      	return Float64(-0.5 * Float64(c / b))
      end
      
      function tmp = code(a, b, c)
      	tmp = -0.5 * (c / b);
      end
      
      code[a_, b_, c_] := N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -0.5 \cdot \frac{c}{b}
      \end{array}
      
      Derivation
      1. Initial program 16.1%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Step-by-step derivation
        1. Simplified16.1%

          \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(b, b, a \cdot \left(c \cdot -3\right)\right)} - b}{3 \cdot a}} \]
        2. Add Preprocessing
        3. Taylor expanded in b around inf 91.6%

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

        Reproduce

        ?
        herbie shell --seed 2024154 
        (FPCore (a b c)
          :name "Cubic critical, wide range"
          :precision binary64
          :pre (and (and (and (< 4.930380657631324e-32 a) (< a 2.028240960365167e+31)) (and (< 4.930380657631324e-32 b) (< b 2.028240960365167e+31))) (and (< 4.930380657631324e-32 c) (< c 2.028240960365167e+31)))
          (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))