Quadratic roots, wide range

Percentage Accurate: 18.6% → 99.4%
Time: 11.1s
Alternatives: 7
Speedup: 3.6×

Specification

?
\[\left(\left(4.930380657631324 \cdot 10^{-32} < a \land a < 2.028240960365167 \cdot 10^{+31}\right) \land \left(4.930380657631324 \cdot 10^{-32} < b \land b < 2.028240960365167 \cdot 10^{+31}\right)\right) \land \left(4.930380657631324 \cdot 10^{-32} < c \land c < 2.028240960365167 \cdot 10^{+31}\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \end{array} \]
(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 7 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 18.6% 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: 99.4% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}{a \cdot 2} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  (/ (fma a (* -4.0 c) 0.0) (+ b (sqrt (fma a (* -4.0 c) (* b b)))))
  (* a 2.0)))
double code(double a, double b, double c) {
	return (fma(a, (-4.0 * c), 0.0) / (b + sqrt(fma(a, (-4.0 * c), (b * b))))) / (a * 2.0);
}
function code(a, b, c)
	return Float64(Float64(fma(a, Float64(-4.0 * c), 0.0) / Float64(b + sqrt(fma(a, Float64(-4.0 * c), Float64(b * b))))) / Float64(a * 2.0))
end
code[a_, b_, c_] := N[(N[(N[(a * N[(-4.0 * c), $MachinePrecision] + 0.0), $MachinePrecision] / N[(b + N[Sqrt[N[(a * N[(-4.0 * c), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(a * 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}{a \cdot 2}
\end{array}
Derivation
  1. Initial program 20.0%

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

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

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

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

      \[\leadsto \frac{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}{2 \cdot a} \]
    5. lower--.f6420.0

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

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

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

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

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

      \[\leadsto \frac{\sqrt{\left(\mathsf{neg}\left(\color{blue}{c \cdot \left(4 \cdot a\right)}\right)\right) + b \cdot b} - b}{2 \cdot a} \]
    11. distribute-rgt-neg-inN/A

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

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{fma}\left(c, \mathsf{neg}\left(4 \cdot a\right), b \cdot b\right)}} - b}{2 \cdot a} \]
    13. lift-*.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \mathsf{neg}\left(\color{blue}{4 \cdot a}\right), b \cdot b\right)} - b}{2 \cdot a} \]
    14. *-commutativeN/A

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \mathsf{neg}\left(\color{blue}{a \cdot 4}\right), b \cdot b\right)} - b}{2 \cdot a} \]
    15. distribute-rgt-neg-inN/A

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

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \color{blue}{a \cdot \left(\mathsf{neg}\left(4\right)\right)}, b \cdot b\right)} - b}{2 \cdot a} \]
    17. metadata-eval20.0

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, a \cdot \color{blue}{-4}, b \cdot b\right)} - b}{2 \cdot a} \]
  4. Applied rewrites20.0%

    \[\leadsto \frac{\color{blue}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b}}{2 \cdot a} \]
  5. Step-by-step derivation
    1. lift--.f64N/A

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

      \[\leadsto \frac{\color{blue}{\frac{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} \cdot \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b \cdot b}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} + b}}}{2 \cdot a} \]
    3. div-invN/A

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

      \[\leadsto \frac{\color{blue}{\left(\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} \cdot \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b \cdot b\right) \cdot \frac{1}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} + b}}}{2 \cdot a} \]
  6. Applied rewrites20.9%

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

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

      \[\leadsto \frac{\left(\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right) - b \cdot b\right) \cdot \color{blue}{\frac{1}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}}{2 \cdot a} \]
    3. un-div-invN/A

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right) - b \cdot b}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}}{2 \cdot a} \]
    4. lower-/.f6420.9

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

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

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

      \[\leadsto \frac{\frac{\color{blue}{c \cdot \left(a \cdot -4\right) + \left(b \cdot b - b \cdot b\right)}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    8. *-commutativeN/A

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

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

      \[\leadsto \frac{\frac{\color{blue}{a \cdot \left(-4 \cdot c\right)} + \left(b \cdot b - b \cdot b\right)}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    11. +-inversesN/A

      \[\leadsto \frac{\frac{a \cdot \left(-4 \cdot c\right) + \color{blue}{0}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    12. lower-fma.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    13. lower-*.f6499.4

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, \color{blue}{-4 \cdot c}, 0\right)}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    14. lift-fma.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{c \cdot \left(a \cdot -4\right) + b \cdot b}}}}{2 \cdot a} \]
    15. *-commutativeN/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\left(a \cdot -4\right) \cdot c} + b \cdot b}}}{2 \cdot a} \]
    16. lift-*.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\left(a \cdot -4\right)} \cdot c + b \cdot b}}}{2 \cdot a} \]
    17. associate-*l*N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{a \cdot \left(-4 \cdot c\right)} + b \cdot b}}}{2 \cdot a} \]
    18. lower-fma.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}}{2 \cdot a} \]
    19. lower-*.f6499.4

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, \color{blue}{-4 \cdot c}, b \cdot b\right)}}}{2 \cdot a} \]
  8. Applied rewrites99.4%

    \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}}{2 \cdot a} \]
  9. Final simplification99.4%

    \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}{a \cdot 2} \]
  10. Add Preprocessing

Alternative 2: 99.4% accurate, 0.8× speedup?

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

\\
\frac{a \cdot \left(-4 \cdot c\right)}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \left(a \cdot 2\right)}
\end{array}
Derivation
  1. Initial program 18.6%

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

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

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

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

      \[\leadsto \frac{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}{2 \cdot a} \]
    5. lower--.f6418.6

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

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

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

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

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

      \[\leadsto \frac{\sqrt{\left(\mathsf{neg}\left(\color{blue}{c \cdot \left(4 \cdot a\right)}\right)\right) + b \cdot b} - b}{2 \cdot a} \]
    11. distribute-rgt-neg-inN/A

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

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{fma}\left(c, \mathsf{neg}\left(4 \cdot a\right), b \cdot b\right)}} - b}{2 \cdot a} \]
    13. lift-*.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \mathsf{neg}\left(\color{blue}{4 \cdot a}\right), b \cdot b\right)} - b}{2 \cdot a} \]
    14. *-commutativeN/A

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \mathsf{neg}\left(\color{blue}{a \cdot 4}\right), b \cdot b\right)} - b}{2 \cdot a} \]
    15. distribute-rgt-neg-inN/A

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

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, \color{blue}{a \cdot \left(\mathsf{neg}\left(4\right)\right)}, b \cdot b\right)} - b}{2 \cdot a} \]
    17. metadata-eval18.6

      \[\leadsto \frac{\sqrt{\mathsf{fma}\left(c, a \cdot \color{blue}{-4}, b \cdot b\right)} - b}{2 \cdot a} \]
  4. Applied rewrites18.6%

    \[\leadsto \frac{\color{blue}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b}}{2 \cdot a} \]
  5. Step-by-step derivation
    1. lift--.f64N/A

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

      \[\leadsto \frac{\color{blue}{\frac{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} \cdot \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b \cdot b}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} + b}}}{2 \cdot a} \]
    3. div-invN/A

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

      \[\leadsto \frac{\color{blue}{\left(\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} \cdot \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} - b \cdot b\right) \cdot \frac{1}{\sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)} + b}}}{2 \cdot a} \]
  6. Applied rewrites19.1%

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

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

      \[\leadsto \frac{\left(\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right) - b \cdot b\right) \cdot \color{blue}{\frac{1}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}}{2 \cdot a} \]
    3. un-div-invN/A

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right) - b \cdot b}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}}{2 \cdot a} \]
    4. lower-/.f6419.1

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

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

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

      \[\leadsto \frac{\frac{\color{blue}{c \cdot \left(a \cdot -4\right) + \left(b \cdot b - b \cdot b\right)}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    8. *-commutativeN/A

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

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

      \[\leadsto \frac{\frac{\color{blue}{a \cdot \left(-4 \cdot c\right)} + \left(b \cdot b - b \cdot b\right)}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    11. +-inversesN/A

      \[\leadsto \frac{\frac{a \cdot \left(-4 \cdot c\right) + \color{blue}{0}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    12. lower-fma.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    13. lower-*.f6499.4

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, \color{blue}{-4 \cdot c}, 0\right)}{b + \sqrt{\mathsf{fma}\left(c, a \cdot -4, b \cdot b\right)}}}{2 \cdot a} \]
    14. lift-fma.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{c \cdot \left(a \cdot -4\right) + b \cdot b}}}}{2 \cdot a} \]
    15. *-commutativeN/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\left(a \cdot -4\right) \cdot c} + b \cdot b}}}{2 \cdot a} \]
    16. lift-*.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\left(a \cdot -4\right)} \cdot c + b \cdot b}}}{2 \cdot a} \]
    17. associate-*l*N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{a \cdot \left(-4 \cdot c\right)} + b \cdot b}}}{2 \cdot a} \]
    18. lower-fma.f64N/A

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\color{blue}{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}}{2 \cdot a} \]
    19. lower-*.f6499.4

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, \color{blue}{-4 \cdot c}, b \cdot b\right)}}}{2 \cdot a} \]
  8. Applied rewrites99.4%

    \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}}{2 \cdot a} \]
  9. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}{2 \cdot a}} \]
    2. lift-/.f64N/A

      \[\leadsto \frac{\color{blue}{\frac{\mathsf{fma}\left(a, -4 \cdot c, 0\right)}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}}{2 \cdot a} \]
    3. lift-fma.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{a \cdot \left(-4 \cdot c\right) + 0}}{b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}}}{2 \cdot a} \]
    4. +-rgt-identityN/A

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

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

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

      \[\leadsto \frac{\color{blue}{a \cdot \left(-4 \cdot c\right)}}{\left(2 \cdot a\right) \cdot \left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right)} \]
    8. *-commutativeN/A

      \[\leadsto \frac{a \cdot \left(-4 \cdot c\right)}{\color{blue}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \left(2 \cdot a\right)}} \]
    9. lower-*.f6499.4

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

      \[\leadsto \frac{a \cdot \left(-4 \cdot c\right)}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \color{blue}{\left(2 \cdot a\right)}} \]
    11. *-commutativeN/A

      \[\leadsto \frac{a \cdot \left(-4 \cdot c\right)}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \color{blue}{\left(a \cdot 2\right)}} \]
    12. lower-*.f6499.4

      \[\leadsto \frac{a \cdot \left(-4 \cdot c\right)}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \color{blue}{\left(a \cdot 2\right)}} \]
  10. Applied rewrites99.4%

    \[\leadsto \color{blue}{\frac{a \cdot \left(-4 \cdot c\right)}{\left(b + \sqrt{\mathsf{fma}\left(a, -4 \cdot c, b \cdot b\right)}\right) \cdot \left(a \cdot 2\right)}} \]
  11. Add Preprocessing

Reproduce

?
herbie shell --seed 2024228 
(FPCore (a b c)
  :name "Quadratic roots, wide range"
  :precision binary64
  :pre (and (and (and (< 4.930380657631324e-32 a) (< a 2.028240960365167e+31)) (and (< 4.930380657631324e-32 b) (< b 2.028240960365167e+31))) (and (< 4.930380657631324e-32 c) (< c 2.028240960365167e+31)))
  (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))