Cubic critical, medium range

Percentage Accurate: 30.9% → 95.4%
Time: 36.7s
Alternatives: 9
Speedup: 23.2×

Specification

?
\[\left(\left(1.1102230246251565 \cdot 10^{-16} < a \land a < 9007199254740992\right) \land \left(1.1102230246251565 \cdot 10^{-16} < b \land b < 9007199254740992\right)\right) \land \left(1.1102230246251565 \cdot 10^{-16} < c \land c < 9007199254740992\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(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 9 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: 30.9% 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: 95.4% accurate, 0.2× speedup?

\[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{\left(a \cdot -1.0546875\right) \cdot {c}^{4}}{{b}^{7}}\right)\right) \end{array} \]
(FPCore (a b c)
 :precision binary64
 (+
  (* -0.5 (/ c b))
  (*
   a
   (+
    (* -0.375 (/ (pow c 2.0) (pow b 3.0)))
    (*
     a
     (+
      (* -0.5625 (/ (pow c 3.0) (pow b 5.0)))
      (/ (* (* a -1.0546875) (pow c 4.0)) (pow b 7.0))))))))
double code(double a, double b, double c) {
	return (-0.5 * (c / b)) + (a * ((-0.375 * (pow(c, 2.0) / pow(b, 3.0))) + (a * ((-0.5625 * (pow(c, 3.0) / pow(b, 5.0))) + (((a * -1.0546875) * pow(c, 4.0)) / pow(b, 7.0))))));
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = ((-0.5d0) * (c / b)) + (a * (((-0.375d0) * ((c ** 2.0d0) / (b ** 3.0d0))) + (a * (((-0.5625d0) * ((c ** 3.0d0) / (b ** 5.0d0))) + (((a * (-1.0546875d0)) * (c ** 4.0d0)) / (b ** 7.0d0))))))
end function
public static double code(double a, double b, double c) {
	return (-0.5 * (c / b)) + (a * ((-0.375 * (Math.pow(c, 2.0) / Math.pow(b, 3.0))) + (a * ((-0.5625 * (Math.pow(c, 3.0) / Math.pow(b, 5.0))) + (((a * -1.0546875) * Math.pow(c, 4.0)) / Math.pow(b, 7.0))))));
}
def code(a, b, c):
	return (-0.5 * (c / b)) + (a * ((-0.375 * (math.pow(c, 2.0) / math.pow(b, 3.0))) + (a * ((-0.5625 * (math.pow(c, 3.0) / math.pow(b, 5.0))) + (((a * -1.0546875) * math.pow(c, 4.0)) / math.pow(b, 7.0))))))
function code(a, b, c)
	return Float64(Float64(-0.5 * Float64(c / b)) + Float64(a * Float64(Float64(-0.375 * Float64((c ^ 2.0) / (b ^ 3.0))) + Float64(a * Float64(Float64(-0.5625 * Float64((c ^ 3.0) / (b ^ 5.0))) + Float64(Float64(Float64(a * -1.0546875) * (c ^ 4.0)) / (b ^ 7.0)))))))
end
function tmp = code(a, b, c)
	tmp = (-0.5 * (c / b)) + (a * ((-0.375 * ((c ^ 2.0) / (b ^ 3.0))) + (a * ((-0.5625 * ((c ^ 3.0) / (b ^ 5.0))) + (((a * -1.0546875) * (c ^ 4.0)) / (b ^ 7.0))))));
end
code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(-0.375 * N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(-0.5625 * N[(N[Power[c, 3.0], $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(a * -1.0546875), $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
-0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{\left(a \cdot -1.0546875\right) \cdot {c}^{4}}{{b}^{7}}\right)\right)
\end{array}
Derivation
  1. Initial program 30.9%

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

    \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + -0.16666666666666666 \cdot \frac{a \cdot \left(1.265625 \cdot \frac{{c}^{4}}{{b}^{6}} + 5.0625 \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
  4. Taylor expanded in c around 0 96.0%

    \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \color{blue}{-1.0546875 \cdot \frac{a \cdot {c}^{4}}{{b}^{7}}}\right)\right) \]
  5. Step-by-step derivation
    1. associate-*r/96.0%

      \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \color{blue}{\frac{-1.0546875 \cdot \left(a \cdot {c}^{4}\right)}{{b}^{7}}}\right)\right) \]
    2. associate-*r*96.0%

      \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{\color{blue}{\left(-1.0546875 \cdot a\right) \cdot {c}^{4}}}{{b}^{7}}\right)\right) \]
  6. Simplified96.0%

    \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \color{blue}{\frac{\left(-1.0546875 \cdot a\right) \cdot {c}^{4}}{{b}^{7}}}\right)\right) \]
  7. Final simplification96.0%

    \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-0.5625 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{\left(a \cdot -1.0546875\right) \cdot {c}^{4}}{{b}^{7}}\right)\right) \]
  8. Add Preprocessing

Alternative 2: 95.1% accurate, 0.3× speedup?

\[\begin{array}{l} \\ c \cdot \left(c \cdot \left(a \cdot \left(a \cdot \left(-1.0546875 \cdot \frac{a \cdot {c}^{2}}{{b}^{7}} + -0.5625 \cdot \frac{c}{{b}^{5}}\right) - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right) \end{array} \]
(FPCore (a b c)
 :precision binary64
 (*
  c
  (-
   (*
    c
    (*
     a
     (-
      (*
       a
       (+
        (* -1.0546875 (/ (* a (pow c 2.0)) (pow b 7.0)))
        (* -0.5625 (/ c (pow b 5.0)))))
      (/ 0.375 (pow b 3.0)))))
   (/ 0.5 b))))
double code(double a, double b, double c) {
	return c * ((c * (a * ((a * ((-1.0546875 * ((a * pow(c, 2.0)) / pow(b, 7.0))) + (-0.5625 * (c / pow(b, 5.0))))) - (0.375 / pow(b, 3.0))))) - (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 * ((c * (a * ((a * (((-1.0546875d0) * ((a * (c ** 2.0d0)) / (b ** 7.0d0))) + ((-0.5625d0) * (c / (b ** 5.0d0))))) - (0.375d0 / (b ** 3.0d0))))) - (0.5d0 / b))
end function
public static double code(double a, double b, double c) {
	return c * ((c * (a * ((a * ((-1.0546875 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 7.0))) + (-0.5625 * (c / Math.pow(b, 5.0))))) - (0.375 / Math.pow(b, 3.0))))) - (0.5 / b));
}
def code(a, b, c):
	return c * ((c * (a * ((a * ((-1.0546875 * ((a * math.pow(c, 2.0)) / math.pow(b, 7.0))) + (-0.5625 * (c / math.pow(b, 5.0))))) - (0.375 / math.pow(b, 3.0))))) - (0.5 / b))
function code(a, b, c)
	return Float64(c * Float64(Float64(c * Float64(a * Float64(Float64(a * Float64(Float64(-1.0546875 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 7.0))) + Float64(-0.5625 * Float64(c / (b ^ 5.0))))) - Float64(0.375 / (b ^ 3.0))))) - Float64(0.5 / b)))
end
function tmp = code(a, b, c)
	tmp = c * ((c * (a * ((a * ((-1.0546875 * ((a * (c ^ 2.0)) / (b ^ 7.0))) + (-0.5625 * (c / (b ^ 5.0))))) - (0.375 / (b ^ 3.0))))) - (0.5 / b));
end
code[a_, b_, c_] := N[(c * N[(N[(c * N[(a * N[(N[(a * N[(N[(-1.0546875 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5625 * N[(c / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
c \cdot \left(c \cdot \left(a \cdot \left(a \cdot \left(-1.0546875 \cdot \frac{a \cdot {c}^{2}}{{b}^{7}} + -0.5625 \cdot \frac{c}{{b}^{5}}\right) - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right)
\end{array}
Derivation
  1. Initial program 30.9%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Add Preprocessing
  3. Taylor expanded in c around 0 95.8%

    \[\leadsto \color{blue}{c \cdot \left(c \cdot \left(-0.375 \cdot \frac{a}{{b}^{3}} + c \cdot \left(-0.5625 \cdot \frac{{a}^{2}}{{b}^{5}} + -0.16666666666666666 \cdot \frac{c \cdot \left(1.265625 \cdot \frac{{a}^{4}}{{b}^{6}} + 5.0625 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a \cdot b}\right)\right) - 0.5 \cdot \frac{1}{b}\right)} \]
  4. Step-by-step derivation
    1. Simplified95.8%

      \[\leadsto \color{blue}{c \cdot \left(c \cdot \mathsf{fma}\left(-0.375, \frac{a}{{b}^{3}}, c \cdot \mathsf{fma}\left(-0.5625, \frac{{a}^{2}}{{b}^{5}}, -0.16666666666666666 \cdot \left(c \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 6.328125}{a \cdot b}\right)\right)\right) - \frac{0.5}{b}\right)} \]
    2. Taylor expanded in c around 0 95.8%

      \[\leadsto c \cdot \left(c \cdot \mathsf{fma}\left(-0.375, \frac{a}{{b}^{3}}, c \cdot \mathsf{fma}\left(-0.5625, \frac{{a}^{2}}{{b}^{5}}, \color{blue}{-1.0546875 \cdot \frac{{a}^{3} \cdot c}{{b}^{7}}}\right)\right) - \frac{0.5}{b}\right) \]
    3. Taylor expanded in a around 0 95.8%

      \[\leadsto c \cdot \left(c \cdot \color{blue}{\left(a \cdot \left(a \cdot \left(-1.0546875 \cdot \frac{a \cdot {c}^{2}}{{b}^{7}} + -0.5625 \cdot \frac{c}{{b}^{5}}\right) - 0.375 \cdot \frac{1}{{b}^{3}}\right)\right)} - \frac{0.5}{b}\right) \]
    4. Taylor expanded in b around 0 95.8%

      \[\leadsto c \cdot \left(c \cdot \left(a \cdot \left(a \cdot \left(-1.0546875 \cdot \frac{a \cdot {c}^{2}}{{b}^{7}} + -0.5625 \cdot \frac{c}{{b}^{5}}\right) - \color{blue}{\frac{0.375}{{b}^{3}}}\right)\right) - \frac{0.5}{b}\right) \]
    5. Add Preprocessing

    Alternative 3: 93.8% accurate, 0.3× speedup?

    \[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + -0.5625 \cdot \frac{a \cdot {c}^{3}}{{b}^{5}}\right) \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (+
      (* -0.5 (/ c b))
      (*
       a
       (+
        (* -0.375 (/ (pow c 2.0) (pow b 3.0)))
        (* -0.5625 (/ (* a (pow c 3.0)) (pow b 5.0)))))))
    double code(double a, double b, double c) {
    	return (-0.5 * (c / b)) + (a * ((-0.375 * (pow(c, 2.0) / pow(b, 3.0))) + (-0.5625 * ((a * pow(c, 3.0)) / pow(b, 5.0)))));
    }
    
    real(8) function code(a, b, c)
        real(8), intent (in) :: a
        real(8), intent (in) :: b
        real(8), intent (in) :: c
        code = ((-0.5d0) * (c / b)) + (a * (((-0.375d0) * ((c ** 2.0d0) / (b ** 3.0d0))) + ((-0.5625d0) * ((a * (c ** 3.0d0)) / (b ** 5.0d0)))))
    end function
    
    public static double code(double a, double b, double c) {
    	return (-0.5 * (c / b)) + (a * ((-0.375 * (Math.pow(c, 2.0) / Math.pow(b, 3.0))) + (-0.5625 * ((a * Math.pow(c, 3.0)) / Math.pow(b, 5.0)))));
    }
    
    def code(a, b, c):
    	return (-0.5 * (c / b)) + (a * ((-0.375 * (math.pow(c, 2.0) / math.pow(b, 3.0))) + (-0.5625 * ((a * math.pow(c, 3.0)) / math.pow(b, 5.0)))))
    
    function code(a, b, c)
    	return Float64(Float64(-0.5 * Float64(c / b)) + Float64(a * Float64(Float64(-0.375 * Float64((c ^ 2.0) / (b ^ 3.0))) + Float64(-0.5625 * Float64(Float64(a * (c ^ 3.0)) / (b ^ 5.0))))))
    end
    
    function tmp = code(a, b, c)
    	tmp = (-0.5 * (c / b)) + (a * ((-0.375 * ((c ^ 2.0) / (b ^ 3.0))) + (-0.5625 * ((a * (c ^ 3.0)) / (b ^ 5.0)))));
    end
    
    code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(a * N[(N[(-0.375 * N[(N[Power[c, 2.0], $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(-0.5625 * N[(N[(a * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + -0.5625 \cdot \frac{a \cdot {c}^{3}}{{b}^{5}}\right)
    \end{array}
    
    Derivation
    1. Initial program 30.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0 94.5%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b} + a \cdot \left(-0.5625 \cdot \frac{a \cdot {c}^{3}}{{b}^{5}} + -0.375 \cdot \frac{{c}^{2}}{{b}^{3}}\right)} \]
    4. Final simplification94.5%

      \[\leadsto -0.5 \cdot \frac{c}{b} + a \cdot \left(-0.375 \cdot \frac{{c}^{2}}{{b}^{3}} + -0.5625 \cdot \frac{a \cdot {c}^{3}}{{b}^{5}}\right) \]
    5. Add Preprocessing

    Alternative 4: 93.8% accurate, 0.3× speedup?

    \[\begin{array}{l} \\ \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{-0.375 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \frac{2}{c}\right)} \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (/
      1.0
      (*
       b
       (-
        (fma
         -3.0
         (/ (* -0.375 (* c (pow a 2.0))) (pow b 4.0))
         (* 1.5 (/ a (pow b 2.0))))
        (/ 2.0 c)))))
    double code(double a, double b, double c) {
    	return 1.0 / (b * (fma(-3.0, ((-0.375 * (c * pow(a, 2.0))) / pow(b, 4.0)), (1.5 * (a / pow(b, 2.0)))) - (2.0 / c)));
    }
    
    function code(a, b, c)
    	return Float64(1.0 / Float64(b * Float64(fma(-3.0, Float64(Float64(-0.375 * Float64(c * (a ^ 2.0))) / (b ^ 4.0)), Float64(1.5 * Float64(a / (b ^ 2.0)))) - Float64(2.0 / c))))
    end
    
    code[a_, b_, c_] := N[(1.0 / N[(b * N[(N[(-3.0 * N[(N[(-0.375 * N[(c * N[Power[a, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] + N[(1.5 * N[(a / N[Power[b, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(2.0 / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{-0.375 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \frac{2}{c}\right)}
    \end{array}
    
    Derivation
    1. Initial program 30.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. cancel-sign-sub-inv30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{b \cdot b + \left(-3 \cdot a\right) \cdot c}}}{3 \cdot a} \]
      2. *-commutative30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \left(-\color{blue}{a \cdot 3}\right) \cdot c}}{3 \cdot a} \]
      3. distribute-rgt-neg-in30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \color{blue}{\left(a \cdot \left(-3\right)\right)} \cdot c}}{3 \cdot a} \]
      4. metadata-eval30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \left(a \cdot \color{blue}{-3}\right) \cdot c}}{3 \cdot a} \]
      5. associate-*r*30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \color{blue}{a \cdot \left(-3 \cdot c\right)}}}{3 \cdot a} \]
      6. *-commutative30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + a \cdot \color{blue}{\left(c \cdot -3\right)}}}{3 \cdot a} \]
      7. flip-+30.8%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\frac{\left(b \cdot b\right) \cdot \left(b \cdot b\right) - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}}{3 \cdot a} \]
      8. pow230.8%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{\color{blue}{{b}^{2}} \cdot \left(b \cdot b\right) - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      9. pow230.8%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{2} \cdot \color{blue}{{b}^{2}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      10. pow-prod-up30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{\color{blue}{{b}^{\left(2 + 2\right)}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      11. metadata-eval30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{\color{blue}{4}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      12. pow230.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - \color{blue}{{\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      13. pow230.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{\color{blue}{{b}^{2}} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
    4. Applied egg-rr30.9%

      \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}}{3 \cdot a} \]
    5. Step-by-step derivation
      1. add-cbrt-cube30.9%

        \[\leadsto \color{blue}{\sqrt[3]{\left(\frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \cdot \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}\right) \cdot \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}}} \]
      2. pow330.9%

        \[\leadsto \sqrt[3]{\color{blue}{{\left(\frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}\right)}^{3}}} \]
    6. Applied egg-rr30.9%

      \[\leadsto \color{blue}{\sqrt[3]{{\left(\frac{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}\right)}{a \cdot 3}\right)}^{3}}} \]
    7. Step-by-step derivation
      1. rem-cbrt-cube31.0%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}\right)}{a \cdot 3}} \]
      2. clear-num31.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{a \cdot 3}{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}\right)}}} \]
      3. associate-*r*31.0%

        \[\leadsto \frac{1}{\frac{a \cdot 3}{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - \color{blue}{\left(a \cdot c\right) \cdot -3}}}\right)}} \]
    8. Applied egg-rr31.0%

      \[\leadsto \color{blue}{\frac{1}{\frac{a \cdot 3}{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - \left(a \cdot c\right) \cdot -3}}\right)}}} \]
    9. Taylor expanded in b around inf 94.4%

      \[\leadsto \frac{1}{\color{blue}{b \cdot \left(\left(-3 \cdot \frac{-0.75 \cdot \left({a}^{2} \cdot c\right) + 0.375 \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} + 1.5 \cdot \frac{a}{{b}^{2}}\right) - 2 \cdot \frac{1}{c}\right)}} \]
    10. Step-by-step derivation
      1. fma-define94.4%

        \[\leadsto \frac{1}{b \cdot \left(\color{blue}{\mathsf{fma}\left(-3, \frac{-0.75 \cdot \left({a}^{2} \cdot c\right) + 0.375 \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right)} - 2 \cdot \frac{1}{c}\right)} \]
      2. distribute-rgt-out94.4%

        \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\color{blue}{\left({a}^{2} \cdot c\right) \cdot \left(-0.75 + 0.375\right)}}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - 2 \cdot \frac{1}{c}\right)} \]
      3. *-commutative94.4%

        \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\color{blue}{\left(c \cdot {a}^{2}\right)} \cdot \left(-0.75 + 0.375\right)}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - 2 \cdot \frac{1}{c}\right)} \]
      4. metadata-eval94.4%

        \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\left(c \cdot {a}^{2}\right) \cdot \color{blue}{-0.375}}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - 2 \cdot \frac{1}{c}\right)} \]
      5. associate-*r/94.4%

        \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\left(c \cdot {a}^{2}\right) \cdot -0.375}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \color{blue}{\frac{2 \cdot 1}{c}}\right)} \]
      6. metadata-eval94.4%

        \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\left(c \cdot {a}^{2}\right) \cdot -0.375}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \frac{\color{blue}{2}}{c}\right)} \]
    11. Simplified94.4%

      \[\leadsto \frac{1}{\color{blue}{b \cdot \left(\mathsf{fma}\left(-3, \frac{\left(c \cdot {a}^{2}\right) \cdot -0.375}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \frac{2}{c}\right)}} \]
    12. Final simplification94.4%

      \[\leadsto \frac{1}{b \cdot \left(\mathsf{fma}\left(-3, \frac{-0.375 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{4}}, 1.5 \cdot \frac{a}{{b}^{2}}\right) - \frac{2}{c}\right)} \]
    13. Add Preprocessing

    Alternative 5: 93.6% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ c \cdot \left(c \cdot \left(a \cdot \left(\frac{-0.5625 \cdot \left(c \cdot a\right)}{{b}^{5}} - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right) \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (*
      c
      (-
       (* c (* a (- (/ (* -0.5625 (* c a)) (pow b 5.0)) (/ 0.375 (pow b 3.0)))))
       (/ 0.5 b))))
    double code(double a, double b, double c) {
    	return c * ((c * (a * (((-0.5625 * (c * a)) / pow(b, 5.0)) - (0.375 / pow(b, 3.0))))) - (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 * ((c * (a * ((((-0.5625d0) * (c * a)) / (b ** 5.0d0)) - (0.375d0 / (b ** 3.0d0))))) - (0.5d0 / b))
    end function
    
    public static double code(double a, double b, double c) {
    	return c * ((c * (a * (((-0.5625 * (c * a)) / Math.pow(b, 5.0)) - (0.375 / Math.pow(b, 3.0))))) - (0.5 / b));
    }
    
    def code(a, b, c):
    	return c * ((c * (a * (((-0.5625 * (c * a)) / math.pow(b, 5.0)) - (0.375 / math.pow(b, 3.0))))) - (0.5 / b))
    
    function code(a, b, c)
    	return Float64(c * Float64(Float64(c * Float64(a * Float64(Float64(Float64(-0.5625 * Float64(c * a)) / (b ^ 5.0)) - Float64(0.375 / (b ^ 3.0))))) - Float64(0.5 / b)))
    end
    
    function tmp = code(a, b, c)
    	tmp = c * ((c * (a * (((-0.5625 * (c * a)) / (b ^ 5.0)) - (0.375 / (b ^ 3.0))))) - (0.5 / b));
    end
    
    code[a_, b_, c_] := N[(c * N[(N[(c * N[(a * N[(N[(N[(-0.5625 * N[(c * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] - N[(0.375 / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    c \cdot \left(c \cdot \left(a \cdot \left(\frac{-0.5625 \cdot \left(c \cdot a\right)}{{b}^{5}} - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right)
    \end{array}
    
    Derivation
    1. Initial program 30.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0 95.8%

      \[\leadsto \color{blue}{c \cdot \left(c \cdot \left(-0.375 \cdot \frac{a}{{b}^{3}} + c \cdot \left(-0.5625 \cdot \frac{{a}^{2}}{{b}^{5}} + -0.16666666666666666 \cdot \frac{c \cdot \left(1.265625 \cdot \frac{{a}^{4}}{{b}^{6}} + 5.0625 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a \cdot b}\right)\right) - 0.5 \cdot \frac{1}{b}\right)} \]
    4. Step-by-step derivation
      1. Simplified95.8%

        \[\leadsto \color{blue}{c \cdot \left(c \cdot \mathsf{fma}\left(-0.375, \frac{a}{{b}^{3}}, c \cdot \mathsf{fma}\left(-0.5625, \frac{{a}^{2}}{{b}^{5}}, -0.16666666666666666 \cdot \left(c \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 6.328125}{a \cdot b}\right)\right)\right) - \frac{0.5}{b}\right)} \]
      2. Taylor expanded in c around 0 95.8%

        \[\leadsto c \cdot \left(c \cdot \mathsf{fma}\left(-0.375, \frac{a}{{b}^{3}}, c \cdot \mathsf{fma}\left(-0.5625, \frac{{a}^{2}}{{b}^{5}}, \color{blue}{-1.0546875 \cdot \frac{{a}^{3} \cdot c}{{b}^{7}}}\right)\right) - \frac{0.5}{b}\right) \]
      3. Taylor expanded in a around 0 94.2%

        \[\leadsto c \cdot \left(c \cdot \color{blue}{\left(a \cdot \left(-0.5625 \cdot \frac{a \cdot c}{{b}^{5}} - 0.375 \cdot \frac{1}{{b}^{3}}\right)\right)} - \frac{0.5}{b}\right) \]
      4. Step-by-step derivation
        1. associate-*r/94.2%

          \[\leadsto c \cdot \left(c \cdot \left(a \cdot \left(\color{blue}{\frac{-0.5625 \cdot \left(a \cdot c\right)}{{b}^{5}}} - 0.375 \cdot \frac{1}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right) \]
        2. associate-*r/94.2%

          \[\leadsto c \cdot \left(c \cdot \left(a \cdot \left(\frac{-0.5625 \cdot \left(a \cdot c\right)}{{b}^{5}} - \color{blue}{\frac{0.375 \cdot 1}{{b}^{3}}}\right)\right) - \frac{0.5}{b}\right) \]
        3. metadata-eval94.2%

          \[\leadsto c \cdot \left(c \cdot \left(a \cdot \left(\frac{-0.5625 \cdot \left(a \cdot c\right)}{{b}^{5}} - \frac{\color{blue}{0.375}}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right) \]
      5. Simplified94.2%

        \[\leadsto c \cdot \left(c \cdot \color{blue}{\left(a \cdot \left(\frac{-0.5625 \cdot \left(a \cdot c\right)}{{b}^{5}} - \frac{0.375}{{b}^{3}}\right)\right)} - \frac{0.5}{b}\right) \]
      6. Final simplification94.2%

        \[\leadsto c \cdot \left(c \cdot \left(a \cdot \left(\frac{-0.5625 \cdot \left(c \cdot a\right)}{{b}^{5}} - \frac{0.375}{{b}^{3}}\right)\right) - \frac{0.5}{b}\right) \]
      7. Add Preprocessing

      Alternative 6: 90.8% accurate, 8.9× speedup?

      \[\begin{array}{l} \\ \frac{1}{-2 \cdot \frac{b}{c} + 1.5 \cdot \frac{a}{b}} \end{array} \]
      (FPCore (a b c)
       :precision binary64
       (/ 1.0 (+ (* -2.0 (/ b c)) (* 1.5 (/ a b)))))
      double code(double a, double b, double c) {
      	return 1.0 / ((-2.0 * (b / c)) + (1.5 * (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 = 1.0d0 / (((-2.0d0) * (b / c)) + (1.5d0 * (a / b)))
      end function
      
      public static double code(double a, double b, double c) {
      	return 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)));
      }
      
      def code(a, b, c):
      	return 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)))
      
      function code(a, b, c)
      	return Float64(1.0 / Float64(Float64(-2.0 * Float64(b / c)) + Float64(1.5 * Float64(a / b))))
      end
      
      function tmp = code(a, b, c)
      	tmp = 1.0 / ((-2.0 * (b / c)) + (1.5 * (a / b)));
      end
      
      code[a_, b_, c_] := N[(1.0 / N[(N[(-2.0 * N[(b / c), $MachinePrecision]), $MachinePrecision] + N[(1.5 * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{1}{-2 \cdot \frac{b}{c} + 1.5 \cdot \frac{a}{b}}
      \end{array}
      
      Derivation
      1. Initial program 30.9%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Add Preprocessing
      3. Taylor expanded in c around 0 90.7%

        \[\leadsto \frac{\color{blue}{c \cdot \left(-1.5 \cdot \frac{a}{b} + -1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}}{3 \cdot a} \]
      4. Step-by-step derivation
        1. clear-num90.7%

          \[\leadsto \color{blue}{\frac{1}{\frac{3 \cdot a}{c \cdot \left(-1.5 \cdot \frac{a}{b} + -1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}}} \]
        2. inv-pow90.7%

          \[\leadsto \color{blue}{{\left(\frac{3 \cdot a}{c \cdot \left(-1.5 \cdot \frac{a}{b} + -1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}\right)}^{-1}} \]
        3. *-commutative90.7%

          \[\leadsto {\left(\frac{\color{blue}{a \cdot 3}}{c \cdot \left(-1.5 \cdot \frac{a}{b} + -1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}\right)}^{-1} \]
        4. fma-define90.6%

          \[\leadsto {\left(\frac{a \cdot 3}{c \cdot \color{blue}{\mathsf{fma}\left(-1.5, \frac{a}{b}, -1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}}\right)}^{-1} \]
        5. associate-*r/90.6%

          \[\leadsto {\left(\frac{a \cdot 3}{c \cdot \mathsf{fma}\left(-1.5, \frac{a}{b}, \color{blue}{\frac{-1.125 \cdot \left({a}^{2} \cdot c\right)}{{b}^{3}}}\right)}\right)}^{-1} \]
        6. *-commutative90.6%

          \[\leadsto {\left(\frac{a \cdot 3}{c \cdot \mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{-1.125 \cdot \color{blue}{\left(c \cdot {a}^{2}\right)}}{{b}^{3}}\right)}\right)}^{-1} \]
      5. Applied egg-rr90.6%

        \[\leadsto \color{blue}{{\left(\frac{a \cdot 3}{c \cdot \mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{-1.125 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{3}}\right)}\right)}^{-1}} \]
      6. Step-by-step derivation
        1. unpow-190.6%

          \[\leadsto \color{blue}{\frac{1}{\frac{a \cdot 3}{c \cdot \mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{-1.125 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{3}}\right)}}} \]
        2. times-frac90.7%

          \[\leadsto \frac{1}{\color{blue}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{-1.125 \cdot \left(c \cdot {a}^{2}\right)}{{b}^{3}}\right)}}} \]
        3. *-commutative90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{-1.125 \cdot \color{blue}{\left({a}^{2} \cdot c\right)}}{{b}^{3}}\right)}} \]
        4. associate-*r/90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \color{blue}{-1.125 \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}}\right)}} \]
        5. associate-*r/90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, -1.125 \cdot \color{blue}{\left({a}^{2} \cdot \frac{c}{{b}^{3}}\right)}\right)}} \]
        6. *-commutative90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \color{blue}{\left({a}^{2} \cdot \frac{c}{{b}^{3}}\right) \cdot -1.125}\right)}} \]
        7. *-commutative90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \color{blue}{\left(\frac{c}{{b}^{3}} \cdot {a}^{2}\right)} \cdot -1.125\right)}} \]
        8. associate-*l*90.7%

          \[\leadsto \frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \color{blue}{\frac{c}{{b}^{3}} \cdot \left({a}^{2} \cdot -1.125\right)}\right)}} \]
      7. Simplified90.7%

        \[\leadsto \color{blue}{\frac{1}{\frac{a}{c} \cdot \frac{3}{\mathsf{fma}\left(-1.5, \frac{a}{b}, \frac{c}{{b}^{3}} \cdot \left({a}^{2} \cdot -1.125\right)\right)}}} \]
      8. Taylor expanded in a around 0 91.4%

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

      Alternative 7: 81.6% accurate, 23.2× speedup?

      \[\begin{array}{l} \\ \frac{-0.5 \cdot c}{b} \end{array} \]
      (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(Float64(-0.5 * c) / b)
      end
      
      function tmp = code(a, b, c)
      	tmp = (-0.5 * c) / b;
      end
      
      code[a_, b_, c_] := N[(N[(-0.5 * c), $MachinePrecision] / b), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{-0.5 \cdot c}{b}
      \end{array}
      
      Derivation
      1. Initial program 30.9%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Add Preprocessing
      3. Taylor expanded in b around inf 81.6%

        \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
      4. Step-by-step derivation
        1. associate-*r/81.6%

          \[\leadsto \color{blue}{\frac{-0.5 \cdot c}{b}} \]
        2. *-commutative81.6%

          \[\leadsto \frac{\color{blue}{c \cdot -0.5}}{b} \]
      5. Simplified81.6%

        \[\leadsto \color{blue}{\frac{c \cdot -0.5}{b}} \]
      6. Final simplification81.6%

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

      Alternative 8: 81.4% accurate, 23.2× 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 30.9%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Add Preprocessing
      3. Taylor expanded in c around 0 91.0%

        \[\leadsto \color{blue}{c \cdot \left(-0.375 \cdot \frac{a \cdot c}{{b}^{3}} - 0.5 \cdot \frac{1}{b}\right)} \]
      4. Taylor expanded in a around 0 81.4%

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

      Alternative 9: 3.2% accurate, 38.7× speedup?

      \[\begin{array}{l} \\ \frac{0}{a} \end{array} \]
      (FPCore (a b c) :precision binary64 (/ 0.0 a))
      double code(double a, double b, double c) {
      	return 0.0 / a;
      }
      
      real(8) function code(a, b, c)
          real(8), intent (in) :: a
          real(8), intent (in) :: b
          real(8), intent (in) :: c
          code = 0.0d0 / a
      end function
      
      public static double code(double a, double b, double c) {
      	return 0.0 / a;
      }
      
      def code(a, b, c):
      	return 0.0 / a
      
      function code(a, b, c)
      	return Float64(0.0 / a)
      end
      
      function tmp = code(a, b, c)
      	tmp = 0.0 / a;
      end
      
      code[a_, b_, c_] := N[(0.0 / a), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{0}{a}
      \end{array}
      
      Derivation
      1. Initial program 30.9%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. cancel-sign-sub-inv30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{b \cdot b + \left(-3 \cdot a\right) \cdot c}}}{3 \cdot a} \]
        2. *-commutative30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \left(-\color{blue}{a \cdot 3}\right) \cdot c}}{3 \cdot a} \]
        3. distribute-rgt-neg-in30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \color{blue}{\left(a \cdot \left(-3\right)\right)} \cdot c}}{3 \cdot a} \]
        4. metadata-eval30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \left(a \cdot \color{blue}{-3}\right) \cdot c}}{3 \cdot a} \]
        5. associate-*r*30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + \color{blue}{a \cdot \left(-3 \cdot c\right)}}}{3 \cdot a} \]
        6. *-commutative30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b + a \cdot \color{blue}{\left(c \cdot -3\right)}}}{3 \cdot a} \]
        7. flip-+30.8%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\frac{\left(b \cdot b\right) \cdot \left(b \cdot b\right) - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}}{3 \cdot a} \]
        8. pow230.8%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{\color{blue}{{b}^{2}} \cdot \left(b \cdot b\right) - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
        9. pow230.8%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{2} \cdot \color{blue}{{b}^{2}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
        10. pow-prod-up30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{\color{blue}{{b}^{\left(2 + 2\right)}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
        11. metadata-eval30.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{\color{blue}{4}} - \left(a \cdot \left(c \cdot -3\right)\right) \cdot \left(a \cdot \left(c \cdot -3\right)\right)}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
        12. pow230.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - \color{blue}{{\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}}{b \cdot b - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
        13. pow230.9%

          \[\leadsto \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{\color{blue}{{b}^{2}} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \]
      4. Applied egg-rr30.9%

        \[\leadsto \frac{\left(-b\right) + \sqrt{\color{blue}{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}}{3 \cdot a} \]
      5. Step-by-step derivation
        1. add-cbrt-cube30.9%

          \[\leadsto \color{blue}{\sqrt[3]{\left(\frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a} \cdot \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}\right) \cdot \frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}}} \]
        2. pow330.9%

          \[\leadsto \sqrt[3]{\color{blue}{{\left(\frac{\left(-b\right) + \sqrt{\frac{{b}^{4} - {\left(a \cdot \left(c \cdot -3\right)\right)}^{2}}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}}{3 \cdot a}\right)}^{3}}} \]
      6. Applied egg-rr30.9%

        \[\leadsto \color{blue}{\sqrt[3]{{\left(\frac{\mathsf{fma}\left(-1, b, \sqrt{\frac{{b}^{4} - {\left(a \cdot c\right)}^{2} \cdot 9}{{b}^{2} - a \cdot \left(c \cdot -3\right)}}\right)}{a \cdot 3}\right)}^{3}}} \]
      7. Taylor expanded in a around 0 3.2%

        \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{b + -1 \cdot b}{a}} \]
      8. Step-by-step derivation
        1. associate-*r/3.2%

          \[\leadsto \color{blue}{\frac{0.3333333333333333 \cdot \left(b + -1 \cdot b\right)}{a}} \]
        2. distribute-rgt1-in3.2%

          \[\leadsto \frac{0.3333333333333333 \cdot \color{blue}{\left(\left(-1 + 1\right) \cdot b\right)}}{a} \]
        3. metadata-eval3.2%

          \[\leadsto \frac{0.3333333333333333 \cdot \left(\color{blue}{0} \cdot b\right)}{a} \]
        4. mul0-lft3.2%

          \[\leadsto \frac{0.3333333333333333 \cdot \color{blue}{0}}{a} \]
        5. metadata-eval3.2%

          \[\leadsto \frac{\color{blue}{0}}{a} \]
      9. Simplified3.2%

        \[\leadsto \color{blue}{\frac{0}{a}} \]
      10. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2024107 
      (FPCore (a b c)
        :name "Cubic critical, medium range"
        :precision binary64
        :pre (and (and (and (< 1.1102230246251565e-16 a) (< a 9007199254740992.0)) (and (< 1.1102230246251565e-16 b) (< b 9007199254740992.0))) (and (< 1.1102230246251565e-16 c) (< c 9007199254740992.0)))
        (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))