Quadratic roots, medium range

Percentage Accurate: 31.4% → 95.5%
Time: 11.1s
Alternatives: 10
Speedup: 3.6×

Specification

?
\[\left(\left(1.1102230246251565 \cdot 10^{-16} < a \land a < 9007199254740992\right) \land \left(1.1102230246251565 \cdot 10^{-16} < b \land b < 9007199254740992\right)\right) \land \left(1.1102230246251565 \cdot 10^{-16} < c \land c < 9007199254740992\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * 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) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \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 10 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: 31.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * 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) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}

Alternative 1: 95.5% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{-{a}^{3}}{{b}^{5}}, -c, \frac{0.5 \cdot \left(a \cdot a\right)}{{b}^{3}}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  0.5
  (/
   (fma
    (fma
     (fma
      (/ (- (pow a 3.0)) (pow b 5.0))
      (- c)
      (/ (* 0.5 (* a a)) (pow b 3.0)))
     c
     (* (/ a b) 0.5))
    c
    (* -0.5 b))
   c)))
double code(double a, double b, double c) {
	return 0.5 / (fma(fma(fma((-pow(a, 3.0) / pow(b, 5.0)), -c, ((0.5 * (a * a)) / pow(b, 3.0))), c, ((a / b) * 0.5)), c, (-0.5 * b)) / c);
}
function code(a, b, c)
	return Float64(0.5 / Float64(fma(fma(fma(Float64(Float64(-(a ^ 3.0)) / (b ^ 5.0)), Float64(-c), Float64(Float64(0.5 * Float64(a * a)) / (b ^ 3.0))), c, Float64(Float64(a / b) * 0.5)), c, Float64(-0.5 * b)) / c))
end
code[a_, b_, c_] := N[(0.5 / N[(N[(N[(N[(N[((-N[Power[a, 3.0], $MachinePrecision]) / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] * (-c) + N[(N[(0.5 * N[(a * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * c + N[(N[(a / b), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision] * c + N[(-0.5 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{-{a}^{3}}{{b}^{5}}, -c, \frac{0.5 \cdot \left(a \cdot a\right)}{{b}^{3}}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}
\end{array}
Derivation
  1. Initial program 31.9%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
    2. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
    4. associate-/l*N/A

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

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    6. metadata-evalN/A

      \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
    7. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    8. lower-/.f6431.9

      \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    9. lift-+.f64N/A

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

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
    11. lift-neg.f64N/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
    12. unsub-negN/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
    13. lower--.f6431.9

      \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
  4. Applied rewrites31.9%

    \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
  5. Taylor expanded in c around 0

    \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(c \cdot \left(-1 \cdot \left(c \cdot \left(-1 \cdot \frac{a \cdot \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)}{{b}^{2}} + \left(\frac{-1}{8} \cdot \frac{b \cdot \left(4 \cdot \frac{{a}^{4}}{{b}^{6}} + 16 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a} + \frac{{a}^{3}}{{b}^{5}}\right)\right)\right) - \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)\right) - \frac{-1}{2} \cdot \frac{a}{b}\right)}{c}}} \]
  6. Applied rewrites95.1%

    \[\leadsto \frac{0.5}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-a, \frac{\frac{a \cdot a}{{b}^{3}} \cdot -0.5}{b \cdot b}, \mathsf{fma}\left(b \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 20}{a}, -0.125, \frac{{a}^{3}}{{b}^{5}}\right)\right), -c, \frac{0.5 \cdot \left(a \cdot a\right)}{{b}^{3}}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}} \]
  7. Taylor expanded in a around 0

    \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-1 \cdot \frac{{a}^{3}}{{b}^{5}}, -c, \frac{\frac{1}{2} \cdot \left(a \cdot a\right)}{{b}^{3}}\right), c, \frac{a}{b} \cdot \frac{1}{2}\right), c, \frac{-1}{2} \cdot b\right)}{c}} \]
  8. Step-by-step derivation
    1. Applied rewrites95.1%

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

    Alternative 2: 95.5% accurate, 0.1× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(\frac{\mathsf{fma}\left(-5 \cdot \left(a \cdot a\right), {c}^{4}, \mathsf{fma}\left(\left(-c\right) \cdot c, b \cdot b, \left({c}^{3} \cdot a\right) \cdot -2\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, \frac{-c}{b}\right) \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (fma
      (/
       (fma
        (* -5.0 (* a a))
        (pow c 4.0)
        (* (fma (* (- c) c) (* b b) (* (* (pow c 3.0) a) -2.0)) (* b b)))
       (pow b 7.0))
      a
      (/ (- c) b)))
    double code(double a, double b, double c) {
    	return fma((fma((-5.0 * (a * a)), pow(c, 4.0), (fma((-c * c), (b * b), ((pow(c, 3.0) * a) * -2.0)) * (b * b))) / pow(b, 7.0)), a, (-c / b));
    }
    
    function code(a, b, c)
    	return fma(Float64(fma(Float64(-5.0 * Float64(a * a)), (c ^ 4.0), Float64(fma(Float64(Float64(-c) * c), Float64(b * b), Float64(Float64((c ^ 3.0) * a) * -2.0)) * Float64(b * b))) / (b ^ 7.0)), a, Float64(Float64(-c) / b))
    end
    
    code[a_, b_, c_] := N[(N[(N[(N[(-5.0 * N[(a * a), $MachinePrecision]), $MachinePrecision] * N[Power[c, 4.0], $MachinePrecision] + N[(N[(N[((-c) * c), $MachinePrecision] * N[(b * b), $MachinePrecision] + N[(N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision] * a + N[((-c) / b), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(\frac{\mathsf{fma}\left(-5 \cdot \left(a \cdot a\right), {c}^{4}, \mathsf{fma}\left(\left(-c\right) \cdot c, b \cdot b, \left({c}^{3} \cdot a\right) \cdot -2\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, \frac{-c}{b}\right)
    \end{array}
    
    Derivation
    1. Initial program 31.9%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{-1 \cdot \frac{c}{b} + a \cdot \left(-1 \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(-2 \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{4} \cdot \frac{a \cdot \left(4 \cdot \frac{{c}^{4}}{{b}^{6}} + 16 \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
    4. Applied rewrites95.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.25 \cdot a, \frac{{c}^{4}}{{b}^{6}} \cdot \frac{20}{b}, \frac{{c}^{3} \cdot -2}{{b}^{5}}\right), a, \left(-c\right) \cdot \frac{c}{{b}^{3}}\right), a, \frac{-c}{b}\right)} \]
    5. Taylor expanded in b around 0

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5 \cdot \left(a \cdot {c}^{4}\right) + -2 \cdot \left({b}^{2} \cdot {c}^{3}\right)}{{b}^{7}}, a, \left(-c\right) \cdot \frac{c}{{b}^{3}}\right), a, \frac{-c}{b}\right) \]
    6. Step-by-step derivation
      1. Applied rewrites95.0%

        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(-5 \cdot {c}^{4}, a, \left(\left(-2 \cdot b\right) \cdot b\right) \cdot {c}^{3}\right)}{{b}^{7}}, a, \left(-c\right) \cdot \frac{c}{{b}^{3}}\right), a, \frac{-c}{b}\right) \]
      2. Taylor expanded in b around 0

        \[\leadsto \mathsf{fma}\left(\frac{-5 \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(-2 \cdot \left(a \cdot {c}^{3}\right) + -1 \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{-c}{b}\right) \]
      3. Step-by-step derivation
        1. Applied rewrites95.0%

          \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(-5 \cdot \left(a \cdot a\right), {c}^{4}, \mathsf{fma}\left(\left(-c\right) \cdot c, b \cdot b, \left({c}^{3} \cdot a\right) \cdot -2\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, \frac{-c}{b}\right) \]
        2. Add Preprocessing

        Alternative 3: 94.0% accurate, 0.3× speedup?

        \[\begin{array}{l} \\ \frac{0.5}{\frac{\mathsf{fma}\left(0.5 \cdot \mathsf{fma}\left(a \cdot a, \frac{c}{{b}^{3}}, \frac{a}{b}\right), c, -0.5 \cdot b\right)}{c}} \end{array} \]
        (FPCore (a b c)
         :precision binary64
         (/
          0.5
          (/ (fma (* 0.5 (fma (* a a) (/ c (pow b 3.0)) (/ a b))) c (* -0.5 b)) c)))
        double code(double a, double b, double c) {
        	return 0.5 / (fma((0.5 * fma((a * a), (c / pow(b, 3.0)), (a / b))), c, (-0.5 * b)) / c);
        }
        
        function code(a, b, c)
        	return Float64(0.5 / Float64(fma(Float64(0.5 * fma(Float64(a * a), Float64(c / (b ^ 3.0)), Float64(a / b))), c, Float64(-0.5 * b)) / c))
        end
        
        code[a_, b_, c_] := N[(0.5 / N[(N[(N[(0.5 * N[(N[(a * a), $MachinePrecision] * N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] + N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * c + N[(-0.5 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{0.5}{\frac{\mathsf{fma}\left(0.5 \cdot \mathsf{fma}\left(a \cdot a, \frac{c}{{b}^{3}}, \frac{a}{b}\right), c, -0.5 \cdot b\right)}{c}}
        \end{array}
        
        Derivation
        1. Initial program 31.9%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-/.f64N/A

            \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
          2. clear-numN/A

            \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
          3. lift-*.f64N/A

            \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
          4. associate-/l*N/A

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

            \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
          6. metadata-evalN/A

            \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
          7. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
          8. lower-/.f6431.9

            \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
          9. lift-+.f64N/A

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

            \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
          11. lift-neg.f64N/A

            \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
          12. unsub-negN/A

            \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
          13. lower--.f6431.9

            \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
        4. Applied rewrites31.9%

          \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
        5. Taylor expanded in b around inf

          \[\leadsto \frac{\frac{1}{2}}{\color{blue}{b \cdot \left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right)}} \]
        6. Step-by-step derivation
          1. *-commutativeN/A

            \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right) \cdot b}} \]
          2. lower-*.f64N/A

            \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right) \cdot b}} \]
        7. Applied rewrites93.4%

          \[\leadsto \frac{0.5}{\color{blue}{\left(-\left(\frac{\left(\left(a \cdot a\right) \cdot c\right) \cdot -0.5}{{b}^{4}} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right)\right) \cdot b}} \]
        8. Taylor expanded in c around 0

          \[\leadsto \frac{\frac{1}{2}}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(\frac{1}{2} \cdot \frac{a}{b} + \frac{1}{2} \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}{\color{blue}{c}}} \]
        9. Step-by-step derivation
          1. Applied rewrites93.5%

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

          Alternative 4: 93.9% accurate, 0.3× speedup?

          \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(\mathsf{fma}\left(0.5 \cdot \frac{c}{{b}^{3}}, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/ 0.5 (fma (fma (* 0.5 (/ c (pow b 3.0))) a (/ 0.5 b)) a (* (/ b c) -0.5))))
          double code(double a, double b, double c) {
          	return 0.5 / fma(fma((0.5 * (c / pow(b, 3.0))), a, (0.5 / b)), a, ((b / c) * -0.5));
          }
          
          function code(a, b, c)
          	return Float64(0.5 / fma(fma(Float64(0.5 * Float64(c / (b ^ 3.0))), a, Float64(0.5 / b)), a, Float64(Float64(b / c) * -0.5)))
          end
          
          code[a_, b_, c_] := N[(0.5 / N[(N[(N[(0.5 * N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * a + N[(0.5 / b), $MachinePrecision]), $MachinePrecision] * a + N[(N[(b / c), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{0.5}{\mathsf{fma}\left(\mathsf{fma}\left(0.5 \cdot \frac{c}{{b}^{3}}, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)}
          \end{array}
          
          Derivation
          1. Initial program 31.9%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
            2. clear-numN/A

              \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            3. lift-*.f64N/A

              \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
            4. associate-/l*N/A

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

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            6. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
            7. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            8. lower-/.f6431.9

              \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            9. lift-+.f64N/A

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

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
            11. lift-neg.f64N/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
            12. unsub-negN/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
            13. lower--.f6431.9

              \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
          4. Applied rewrites31.9%

            \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
          5. Taylor expanded in a around 0

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

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

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

              \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\mathsf{fma}\left(-1 \cdot \left(a \cdot \left(-1 \cdot \frac{c}{{b}^{3}} + \frac{1}{2} \cdot \frac{c}{{b}^{3}}\right)\right) + \frac{1}{2} \cdot \frac{1}{b}, a, \frac{-1}{2} \cdot \frac{b}{c}\right)}} \]
          7. Applied rewrites93.5%

            \[\leadsto \frac{0.5}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.5 \cdot \frac{c}{{b}^{3}}, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)}} \]
          8. Add Preprocessing

          Alternative 5: 93.8% accurate, 0.5× speedup?

          \[\begin{array}{l} \\ \frac{0.5}{\left(\frac{\frac{\left(c \cdot \left(a \cdot a\right)\right) \cdot -0.5}{b \cdot b}}{b \cdot b} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right) \cdot \left(-b\right)} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/
            0.5
            (*
             (+
              (/ (/ (* (* c (* a a)) -0.5) (* b b)) (* b b))
              (fma (/ a (* b b)) -0.5 (/ 0.5 c)))
             (- b))))
          double code(double a, double b, double c) {
          	return 0.5 / ((((((c * (a * a)) * -0.5) / (b * b)) / (b * b)) + fma((a / (b * b)), -0.5, (0.5 / c))) * -b);
          }
          
          function code(a, b, c)
          	return Float64(0.5 / Float64(Float64(Float64(Float64(Float64(Float64(c * Float64(a * a)) * -0.5) / Float64(b * b)) / Float64(b * b)) + fma(Float64(a / Float64(b * b)), -0.5, Float64(0.5 / c))) * Float64(-b)))
          end
          
          code[a_, b_, c_] := N[(0.5 / N[(N[(N[(N[(N[(N[(c * N[(a * a), $MachinePrecision]), $MachinePrecision] * -0.5), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(N[(a / N[(b * b), $MachinePrecision]), $MachinePrecision] * -0.5 + N[(0.5 / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * (-b)), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{0.5}{\left(\frac{\frac{\left(c \cdot \left(a \cdot a\right)\right) \cdot -0.5}{b \cdot b}}{b \cdot b} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right) \cdot \left(-b\right)}
          \end{array}
          
          Derivation
          1. Initial program 31.9%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
            2. clear-numN/A

              \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            3. lift-*.f64N/A

              \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
            4. associate-/l*N/A

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

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            6. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
            7. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            8. lower-/.f6431.9

              \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            9. lift-+.f64N/A

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

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
            11. lift-neg.f64N/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
            12. unsub-negN/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
            13. lower--.f6431.9

              \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
          4. Applied rewrites31.9%

            \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
          5. Taylor expanded in b around inf

            \[\leadsto \frac{\frac{1}{2}}{\color{blue}{b \cdot \left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right)}} \]
          6. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right) \cdot b}} \]
            2. lower-*.f64N/A

              \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\left(-1 \cdot \frac{-1 \cdot \left({a}^{2} \cdot c\right) + \frac{1}{2} \cdot \left({a}^{2} \cdot c\right)}{{b}^{4}} - \left(\frac{-1}{2} \cdot \frac{a}{{b}^{2}} + \frac{1}{2} \cdot \frac{1}{c}\right)\right) \cdot b}} \]
          7. Applied rewrites93.4%

            \[\leadsto \frac{0.5}{\color{blue}{\left(-\left(\frac{\left(\left(a \cdot a\right) \cdot c\right) \cdot -0.5}{{b}^{4}} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right)\right) \cdot b}} \]
          8. Step-by-step derivation
            1. Applied rewrites93.4%

              \[\leadsto \frac{0.5}{\left(-\left(\frac{\frac{\left(c \cdot \left(a \cdot a\right)\right) \cdot -0.5}{b \cdot b}}{b \cdot b} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right)\right) \cdot b} \]
            2. Final simplification93.4%

              \[\leadsto \frac{0.5}{\left(\frac{\frac{\left(c \cdot \left(a \cdot a\right)\right) \cdot -0.5}{b \cdot b}}{b \cdot b} + \mathsf{fma}\left(\frac{a}{b \cdot b}, -0.5, \frac{0.5}{c}\right)\right) \cdot \left(-b\right)} \]
            3. Add Preprocessing

            Alternative 6: 90.8% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \frac{0.5}{\frac{\mathsf{fma}\left(a \cdot \frac{c}{b}, 0.5, -0.5 \cdot b\right)}{c}} \end{array} \]
            (FPCore (a b c)
             :precision binary64
             (/ 0.5 (/ (fma (* a (/ c b)) 0.5 (* -0.5 b)) c)))
            double code(double a, double b, double c) {
            	return 0.5 / (fma((a * (c / b)), 0.5, (-0.5 * b)) / c);
            }
            
            function code(a, b, c)
            	return Float64(0.5 / Float64(fma(Float64(a * Float64(c / b)), 0.5, Float64(-0.5 * b)) / c))
            end
            
            code[a_, b_, c_] := N[(0.5 / N[(N[(N[(a * N[(c / b), $MachinePrecision]), $MachinePrecision] * 0.5 + N[(-0.5 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{0.5}{\frac{\mathsf{fma}\left(a \cdot \frac{c}{b}, 0.5, -0.5 \cdot b\right)}{c}}
            \end{array}
            
            Derivation
            1. Initial program 31.9%

              \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-/.f64N/A

                \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
              2. clear-numN/A

                \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              3. lift-*.f64N/A

                \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
              4. associate-/l*N/A

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

                \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              6. metadata-evalN/A

                \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
              7. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              8. lower-/.f6431.9

                \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              9. lift-+.f64N/A

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

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
              11. lift-neg.f64N/A

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
              12. unsub-negN/A

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
              13. lower--.f6431.9

                \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
            4. Applied rewrites31.9%

              \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
            5. Taylor expanded in c around 0

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

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

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

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

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

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

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

                \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(a \cdot \color{blue}{\frac{c}{b}}, \frac{1}{2}, \frac{-1}{2} \cdot b\right)}{c}} \]
              8. lower-*.f6490.3

                \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(a \cdot \frac{c}{b}, 0.5, \color{blue}{-0.5 \cdot b}\right)}{c}} \]
            7. Applied rewrites90.3%

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

            Alternative 7: 90.8% accurate, 1.1× speedup?

            \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.5\right)} \end{array} \]
            (FPCore (a b c) :precision binary64 (/ 0.5 (fma (/ a b) 0.5 (* (/ b c) -0.5))))
            double code(double a, double b, double c) {
            	return 0.5 / fma((a / b), 0.5, ((b / c) * -0.5));
            }
            
            function code(a, b, c)
            	return Float64(0.5 / fma(Float64(a / b), 0.5, Float64(Float64(b / c) * -0.5)))
            end
            
            code[a_, b_, c_] := N[(0.5 / N[(N[(a / b), $MachinePrecision] * 0.5 + N[(N[(b / c), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.5\right)}
            \end{array}
            
            Derivation
            1. Initial program 31.9%

              \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-/.f64N/A

                \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
              2. clear-numN/A

                \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              3. lift-*.f64N/A

                \[\leadsto \frac{1}{\frac{\color{blue}{2 \cdot a}}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
              4. associate-/l*N/A

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

                \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              6. metadata-evalN/A

                \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
              7. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              8. lower-/.f6431.9

                \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
              9. lift-+.f64N/A

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

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
              11. lift-neg.f64N/A

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
              12. unsub-negN/A

                \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
              13. lower--.f6431.9

                \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
            4. Applied rewrites31.9%

              \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
            5. Taylor expanded in a around 0

              \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{-1}{2} \cdot \frac{b}{c} + \frac{1}{2} \cdot \frac{a}{b}}} \]
            6. Step-by-step derivation
              1. +-commutativeN/A

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

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

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

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

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

                \[\leadsto \frac{\frac{1}{2}}{\mathsf{fma}\left(\frac{a}{b}, \frac{1}{2}, \color{blue}{\frac{b}{c} \cdot \frac{-1}{2}}\right)} \]
              7. lower-/.f6490.3

                \[\leadsto \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \color{blue}{\frac{b}{c}} \cdot -0.5\right)} \]
            7. Applied rewrites90.3%

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

            Alternative 8: 90.7% accurate, 1.2× speedup?

            \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(-a, \frac{c}{b \cdot b}, -1\right) \cdot c}{b} \end{array} \]
            (FPCore (a b c) :precision binary64 (/ (* (fma (- a) (/ c (* b b)) -1.0) c) b))
            double code(double a, double b, double c) {
            	return (fma(-a, (c / (b * b)), -1.0) * c) / b;
            }
            
            function code(a, b, c)
            	return Float64(Float64(fma(Float64(-a), Float64(c / Float64(b * b)), -1.0) * c) / b)
            end
            
            code[a_, b_, c_] := N[(N[(N[((-a) * N[(c / N[(b * b), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision] * c), $MachinePrecision] / b), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{\mathsf{fma}\left(-a, \frac{c}{b \cdot b}, -1\right) \cdot c}{b}
            \end{array}
            
            Derivation
            1. Initial program 31.9%

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

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

                \[\leadsto \color{blue}{\frac{-2 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(-1 \cdot c + -1 \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
            5. Applied rewrites93.4%

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

              \[\leadsto \frac{c \cdot \left(-1 \cdot \frac{a \cdot c}{{b}^{2}} - 1\right)}{b} \]
            7. Step-by-step derivation
              1. Applied rewrites90.1%

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

              Alternative 9: 90.4% accurate, 1.2× speedup?

              \[\begin{array}{l} \\ \frac{-1 - \frac{c \cdot a}{b \cdot b}}{b} \cdot c \end{array} \]
              (FPCore (a b c) :precision binary64 (* (/ (- -1.0 (/ (* c a) (* b b))) b) c))
              double code(double a, double b, double c) {
              	return ((-1.0 - ((c * a) / (b * b))) / b) * c;
              }
              
              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) - ((c * a) / (b * b))) / b) * c
              end function
              
              public static double code(double a, double b, double c) {
              	return ((-1.0 - ((c * a) / (b * b))) / b) * c;
              }
              
              def code(a, b, c):
              	return ((-1.0 - ((c * a) / (b * b))) / b) * c
              
              function code(a, b, c)
              	return Float64(Float64(Float64(-1.0 - Float64(Float64(c * a) / Float64(b * b))) / b) * c)
              end
              
              function tmp = code(a, b, c)
              	tmp = ((-1.0 - ((c * a) / (b * b))) / b) * c;
              end
              
              code[a_, b_, c_] := N[(N[(N[(-1.0 - N[(N[(c * a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision] * c), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{-1 - \frac{c \cdot a}{b \cdot b}}{b} \cdot c
              \end{array}
              
              Derivation
              1. Initial program 31.9%

                \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
              2. Add Preprocessing
              3. Taylor expanded in c around 0

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

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

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

                  \[\leadsto \left(-1 \cdot \frac{a \cdot c}{{b}^{3}} + \color{blue}{\frac{\mathsf{neg}\left(1\right)}{b}}\right) \cdot c \]
                4. metadata-evalN/A

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

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

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

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

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

                  \[\leadsto \color{blue}{\left(\left(-1 \cdot \frac{a}{{b}^{3}}\right) \cdot c + \frac{-1}{b}\right) \cdot c} \]
              5. Applied rewrites89.9%

                \[\leadsto \color{blue}{\left(-\mathsf{fma}\left(\frac{c}{{b}^{3}}, a, \frac{1}{b}\right)\right) \cdot c} \]
              6. Step-by-step derivation
                1. Applied rewrites89.9%

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

                Alternative 10: 81.3% accurate, 3.6× speedup?

                \[\begin{array}{l} \\ \frac{-c}{b} \end{array} \]
                (FPCore (a b c) :precision binary64 (/ (- c) b))
                double code(double a, double b, double c) {
                	return -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 = -c / b
                end function
                
                public static double code(double a, double b, double c) {
                	return -c / b;
                }
                
                def code(a, b, c):
                	return -c / b
                
                function code(a, b, c)
                	return Float64(Float64(-c) / b)
                end
                
                function tmp = code(a, b, c)
                	tmp = -c / b;
                end
                
                code[a_, b_, c_] := N[((-c) / b), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \frac{-c}{b}
                \end{array}
                
                Derivation
                1. Initial program 31.9%

                  \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
                2. Add Preprocessing
                3. Taylor expanded in a around 0

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

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

                    \[\leadsto \color{blue}{\frac{-1 \cdot c}{b}} \]
                  3. mul-1-negN/A

                    \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(c\right)}}{b} \]
                  4. lower-neg.f6480.9

                    \[\leadsto \frac{\color{blue}{-c}}{b} \]
                5. Applied rewrites80.9%

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

                Reproduce

                ?
                herbie shell --seed 2024327 
                (FPCore (a b c)
                  :name "Quadratic roots, 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) (* (* 4.0 a) c)))) (* 2.0 a)))