quad2p (problem 3.2.1, positive)

Percentage Accurate: 52.9% → 86.3%
Time: 5.0s
Alternatives: 7
Speedup: 1.7×

Specification

?
\[\begin{array}{l} \\ \frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 + Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 + math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) + sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) + N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{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: 52.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 + Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 + math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) + sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) + N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}
\end{array}

Alternative 1: 86.3% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -1 \cdot 10^{+154}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\ \;\;\;\;\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -1e+154)
   (/ (* -2.0 b_2) a)
   (if (<= b_2 2.35e-116)
     (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a)
     (* (/ c b_2) -0.5))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e+154) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-1d+154)) then
        tmp = ((-2.0d0) * b_2) / a
    else if (b_2 <= 2.35d-116) then
        tmp = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1e+154) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = (-b_2 + Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -1e+154:
		tmp = (-2.0 * b_2) / a
	elif b_2 <= 2.35e-116:
		tmp = (-b_2 + math.sqrt(((b_2 * b_2) - (a * c)))) / a
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -1e+154)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	elseif (b_2 <= 2.35e-116)
		tmp = Float64(Float64(Float64(-b_2) + sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a);
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -1e+154)
		tmp = (-2.0 * b_2) / a;
	elseif (b_2 <= 2.35e-116)
		tmp = (-b_2 + sqrt(((b_2 * b_2) - (a * c)))) / a;
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1e+154], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, 2.35e-116], N[(N[((-b$95$2) + N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -1 \cdot 10^{+154}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\
\;\;\;\;\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -1.00000000000000004e154

    1. Initial program 39.1%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6495.8

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites95.8%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -1.00000000000000004e154 < b_2 < 2.34999999999999997e-116

    1. Initial program 82.6%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing

    if 2.34999999999999997e-116 < b_2

    1. Initial program 17.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6486.2

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites86.2%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 2: 71.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\frac{-c}{a}}\\ t_1 := -t\_0\\ \mathbf{if}\;b\_2 \leq -1.35 \cdot 10^{-128}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{elif}\;b\_2 \leq -8 \cdot 10^{-268}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;b\_2 \leq 4.6 \cdot 10^{-195}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;b\_2 \leq 1.05 \cdot 10^{-116}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (sqrt (/ (- c) a))) (t_1 (- t_0)))
   (if (<= b_2 -1.35e-128)
     (/ (* -2.0 b_2) a)
     (if (<= b_2 -8e-268)
       t_1
       (if (<= b_2 4.6e-195)
         t_0
         (if (<= b_2 1.05e-116) t_1 (* (/ c b_2) -0.5)))))))
double code(double a, double b_2, double c) {
	double t_0 = sqrt((-c / a));
	double t_1 = -t_0;
	double tmp;
	if (b_2 <= -1.35e-128) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= -8e-268) {
		tmp = t_1;
	} else if (b_2 <= 4.6e-195) {
		tmp = t_0;
	} else if (b_2 <= 1.05e-116) {
		tmp = t_1;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = sqrt((-c / a))
    t_1 = -t_0
    if (b_2 <= (-1.35d-128)) then
        tmp = ((-2.0d0) * b_2) / a
    else if (b_2 <= (-8d-268)) then
        tmp = t_1
    else if (b_2 <= 4.6d-195) then
        tmp = t_0
    else if (b_2 <= 1.05d-116) then
        tmp = t_1
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double t_0 = Math.sqrt((-c / a));
	double t_1 = -t_0;
	double tmp;
	if (b_2 <= -1.35e-128) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= -8e-268) {
		tmp = t_1;
	} else if (b_2 <= 4.6e-195) {
		tmp = t_0;
	} else if (b_2 <= 1.05e-116) {
		tmp = t_1;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	t_0 = math.sqrt((-c / a))
	t_1 = -t_0
	tmp = 0
	if b_2 <= -1.35e-128:
		tmp = (-2.0 * b_2) / a
	elif b_2 <= -8e-268:
		tmp = t_1
	elif b_2 <= 4.6e-195:
		tmp = t_0
	elif b_2 <= 1.05e-116:
		tmp = t_1
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	t_0 = sqrt(Float64(Float64(-c) / a))
	t_1 = Float64(-t_0)
	tmp = 0.0
	if (b_2 <= -1.35e-128)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	elseif (b_2 <= -8e-268)
		tmp = t_1;
	elseif (b_2 <= 4.6e-195)
		tmp = t_0;
	elseif (b_2 <= 1.05e-116)
		tmp = t_1;
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	t_0 = sqrt((-c / a));
	t_1 = -t_0;
	tmp = 0.0;
	if (b_2 <= -1.35e-128)
		tmp = (-2.0 * b_2) / a;
	elseif (b_2 <= -8e-268)
		tmp = t_1;
	elseif (b_2 <= 4.6e-195)
		tmp = t_0;
	elseif (b_2 <= 1.05e-116)
		tmp = t_1;
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[Sqrt[N[((-c) / a), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = (-t$95$0)}, If[LessEqual[b$95$2, -1.35e-128], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, -8e-268], t$95$1, If[LessEqual[b$95$2, 4.6e-195], t$95$0, If[LessEqual[b$95$2, 1.05e-116], t$95$1, N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\frac{-c}{a}}\\
t_1 := -t\_0\\
\mathbf{if}\;b\_2 \leq -1.35 \cdot 10^{-128}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{elif}\;b\_2 \leq -8 \cdot 10^{-268}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;b\_2 \leq 4.6 \cdot 10^{-195}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;b\_2 \leq 1.05 \cdot 10^{-116}:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if b_2 < -1.35000000000000003e-128

    1. Initial program 69.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6484.2

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites84.2%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -1.35000000000000003e-128 < b_2 < -7.99999999999999966e-268 or 4.6000000000000004e-195 < b_2 < 1.05e-116

    1. Initial program 81.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}} \]
      2. lift-neg.f64N/A

        \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(b\_2\right)\right)} + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      3. lift-+.f64N/A

        \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(b\_2\right)\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}}{a} \]
      4. lift-sqrt.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\_2\right)\right) + \color{blue}{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}}{a} \]
      5. lift--.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\_2\right)\right) + \sqrt{\color{blue}{b\_2 \cdot b\_2 - a \cdot c}}}{a} \]
      6. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\_2\right)\right) + \sqrt{\color{blue}{b\_2 \cdot b\_2} - a \cdot c}}{a} \]
      7. lift-*.f64N/A

        \[\leadsto \frac{\left(\mathsf{neg}\left(b\_2\right)\right) + \sqrt{b\_2 \cdot b\_2 - \color{blue}{a \cdot c}}}{a} \]
      8. div-addN/A

        \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(b\_2\right)}{a} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}} \]
      9. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{-1 \cdot b\_2}}{a} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      10. associate-*r/N/A

        \[\leadsto \color{blue}{-1 \cdot \frac{b\_2}{a}} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      11. lower-+.f64N/A

        \[\leadsto \color{blue}{-1 \cdot \frac{b\_2}{a} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}} \]
      12. associate-*r/N/A

        \[\leadsto \color{blue}{\frac{-1 \cdot b\_2}{a}} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      13. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(b\_2\right)}}{a} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      14. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(b\_2\right)}{a}} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      15. lift-neg.f64N/A

        \[\leadsto \frac{\color{blue}{-b\_2}}{a} + \frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      16. lower-/.f64N/A

        \[\leadsto \frac{-b\_2}{a} + \color{blue}{\frac{\sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}} \]
    4. Applied rewrites81.5%

      \[\leadsto \color{blue}{\frac{-b\_2}{a} + \frac{\sqrt{\mathsf{fma}\left(-a, c, b\_2 \cdot b\_2\right)}}{a}} \]
    5. Taylor expanded in a around -inf

      \[\leadsto \color{blue}{-1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right)} \]
    6. Step-by-step derivation
      1. div-add-revN/A

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

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

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      4. pow2N/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      5. +-commutativeN/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      6. lift-*.f64N/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      7. lift-neg.f64N/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      8. fp-cancel-sub-sign-invN/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      9. pow2N/A

        \[\leadsto -1 \cdot \left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      10. mul-1-negN/A

        \[\leadsto \mathsf{neg}\left(\sqrt{\frac{c}{a}} \cdot \sqrt{-1}\right) \]
      11. lower-neg.f64N/A

        \[\leadsto -\sqrt{\frac{c}{a}} \cdot \sqrt{-1} \]
      12. sqrt-prodN/A

        \[\leadsto -\sqrt{\frac{c}{a} \cdot -1} \]
      13. lower-sqrt.f64N/A

        \[\leadsto -\sqrt{\frac{c}{a} \cdot -1} \]
      14. *-commutativeN/A

        \[\leadsto -\sqrt{-1 \cdot \frac{c}{a}} \]
      15. associate-*r/N/A

        \[\leadsto -\sqrt{\frac{-1 \cdot c}{a}} \]
      16. mul-1-negN/A

        \[\leadsto -\sqrt{\frac{\mathsf{neg}\left(c\right)}{a}} \]
    7. Applied rewrites50.3%

      \[\leadsto \color{blue}{-\sqrt{\frac{-c}{a}}} \]

    if -7.99999999999999966e-268 < b_2 < 4.6000000000000004e-195

    1. Initial program 48.1%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf

      \[\leadsto \color{blue}{\sqrt{\frac{c}{a}} \cdot \sqrt{-1}} \]
    4. Step-by-step derivation
      1. sqrt-unprodN/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      3. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      4. lower-/.f6468.7

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
    5. Applied rewrites68.7%

      \[\leadsto \color{blue}{\sqrt{\frac{c}{a} \cdot -1}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      3. *-commutativeN/A

        \[\leadsto \sqrt{-1 \cdot \frac{c}{a}} \]
      4. associate-*r/N/A

        \[\leadsto \sqrt{\frac{-1 \cdot c}{a}} \]
      5. mul-1-negN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(c\right)}{a}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(c\right)}{a}} \]
      7. lower-neg.f6468.7

        \[\leadsto \sqrt{\frac{-c}{a}} \]
    7. Applied rewrites68.7%

      \[\leadsto \color{blue}{\sqrt{\frac{-c}{a}}} \]

    if 1.05e-116 < b_2

    1. Initial program 17.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6486.2

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites86.2%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 4 regimes into one program.
  4. Add Preprocessing

Alternative 3: 80.7% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -7.5 \cdot 10^{-118}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\ \;\;\;\;\frac{\left(-b\_2\right) + \sqrt{\left(-a\right) \cdot c}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -7.5e-118)
   (/ (* -2.0 b_2) a)
   (if (<= b_2 2.35e-116)
     (/ (+ (- b_2) (sqrt (* (- a) c))) a)
     (* (/ c b_2) -0.5))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -7.5e-118) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = (-b_2 + sqrt((-a * c))) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-7.5d-118)) then
        tmp = ((-2.0d0) * b_2) / a
    else if (b_2 <= 2.35d-116) then
        tmp = (-b_2 + sqrt((-a * c))) / a
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -7.5e-118) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = (-b_2 + Math.sqrt((-a * c))) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -7.5e-118:
		tmp = (-2.0 * b_2) / a
	elif b_2 <= 2.35e-116:
		tmp = (-b_2 + math.sqrt((-a * c))) / a
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -7.5e-118)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	elseif (b_2 <= 2.35e-116)
		tmp = Float64(Float64(Float64(-b_2) + sqrt(Float64(Float64(-a) * c))) / a);
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -7.5e-118)
		tmp = (-2.0 * b_2) / a;
	elseif (b_2 <= 2.35e-116)
		tmp = (-b_2 + sqrt((-a * c))) / a;
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -7.5e-118], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, 2.35e-116], N[(N[((-b$95$2) + N[Sqrt[N[((-a) * c), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision], N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -7.5 \cdot 10^{-118}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\
\;\;\;\;\frac{\left(-b\_2\right) + \sqrt{\left(-a\right) \cdot c}}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -7.49999999999999978e-118

    1. Initial program 69.2%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6484.9

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites84.9%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -7.49999999999999978e-118 < b_2 < 2.34999999999999997e-116

    1. Initial program 72.8%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf

      \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\color{blue}{-1 \cdot \left(a \cdot c\right)}}}{a} \]
    4. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\left(-1 \cdot a\right) \cdot \color{blue}{c}}}{a} \]
      2. mul-1-negN/A

        \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\left(\mathsf{neg}\left(a\right)\right) \cdot c}}{a} \]
      3. lower-*.f64N/A

        \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\left(\mathsf{neg}\left(a\right)\right) \cdot \color{blue}{c}}}{a} \]
      4. lower-neg.f6472.7

        \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\left(-a\right) \cdot c}}{a} \]
    5. Applied rewrites72.7%

      \[\leadsto \frac{\left(-b\_2\right) + \sqrt{\color{blue}{\left(-a\right) \cdot c}}}{a} \]

    if 2.34999999999999997e-116 < b_2

    1. Initial program 17.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6486.2

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites86.2%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 4: 80.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -3.5 \cdot 10^{-118}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\ \;\;\;\;\frac{\sqrt{\left(-a\right) \cdot c}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -3.5e-118)
   (/ (* -2.0 b_2) a)
   (if (<= b_2 2.35e-116) (/ (sqrt (* (- a) c)) a) (* (/ c b_2) -0.5))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -3.5e-118) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = sqrt((-a * c)) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-3.5d-118)) then
        tmp = ((-2.0d0) * b_2) / a
    else if (b_2 <= 2.35d-116) then
        tmp = sqrt((-a * c)) / a
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -3.5e-118) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.35e-116) {
		tmp = Math.sqrt((-a * c)) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -3.5e-118:
		tmp = (-2.0 * b_2) / a
	elif b_2 <= 2.35e-116:
		tmp = math.sqrt((-a * c)) / a
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -3.5e-118)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	elseif (b_2 <= 2.35e-116)
		tmp = Float64(sqrt(Float64(Float64(-a) * c)) / a);
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -3.5e-118)
		tmp = (-2.0 * b_2) / a;
	elseif (b_2 <= 2.35e-116)
		tmp = sqrt((-a * c)) / a;
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -3.5e-118], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, 2.35e-116], N[(N[Sqrt[N[((-a) * c), $MachinePrecision]], $MachinePrecision] / a), $MachinePrecision], N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -3.5 \cdot 10^{-118}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{elif}\;b\_2 \leq 2.35 \cdot 10^{-116}:\\
\;\;\;\;\frac{\sqrt{\left(-a\right) \cdot c}}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -3.5e-118

    1. Initial program 69.2%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6484.9

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites84.9%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -3.5e-118 < b_2 < 2.34999999999999997e-116

    1. Initial program 72.8%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf

      \[\leadsto \frac{\color{blue}{\sqrt{a \cdot c} \cdot \sqrt{-1}}}{a} \]
    4. Step-by-step derivation
      1. sqrt-unprodN/A

        \[\leadsto \frac{\sqrt{\left(a \cdot c\right) \cdot -1}}{a} \]
      2. *-commutativeN/A

        \[\leadsto \frac{\sqrt{-1 \cdot \left(a \cdot c\right)}}{a} \]
      3. lower-sqrt.f64N/A

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

        \[\leadsto \frac{\sqrt{\left(-1 \cdot a\right) \cdot c}}{a} \]
      5. mul-1-negN/A

        \[\leadsto \frac{\sqrt{\left(\mathsf{neg}\left(a\right)\right) \cdot c}}{a} \]
      6. lower-*.f64N/A

        \[\leadsto \frac{\sqrt{\left(\mathsf{neg}\left(a\right)\right) \cdot c}}{a} \]
      7. lower-neg.f6471.4

        \[\leadsto \frac{\sqrt{\left(-a\right) \cdot c}}{a} \]
    5. Applied rewrites71.4%

      \[\leadsto \frac{\color{blue}{\sqrt{\left(-a\right) \cdot c}}}{a} \]

    if 2.34999999999999997e-116 < b_2

    1. Initial program 17.5%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6486.2

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites86.2%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 5: 71.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -4.2 \cdot 10^{-218}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{elif}\;b\_2 \leq 2.32 \cdot 10^{-209}:\\ \;\;\;\;\sqrt{\frac{-c}{a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -4.2e-218)
   (/ (* -2.0 b_2) a)
   (if (<= b_2 2.32e-209) (sqrt (/ (- c) a)) (* (/ c b_2) -0.5))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -4.2e-218) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.32e-209) {
		tmp = sqrt((-c / a));
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-4.2d-218)) then
        tmp = ((-2.0d0) * b_2) / a
    else if (b_2 <= 2.32d-209) then
        tmp = sqrt((-c / a))
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -4.2e-218) {
		tmp = (-2.0 * b_2) / a;
	} else if (b_2 <= 2.32e-209) {
		tmp = Math.sqrt((-c / a));
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -4.2e-218:
		tmp = (-2.0 * b_2) / a
	elif b_2 <= 2.32e-209:
		tmp = math.sqrt((-c / a))
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -4.2e-218)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	elseif (b_2 <= 2.32e-209)
		tmp = sqrt(Float64(Float64(-c) / a));
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -4.2e-218)
		tmp = (-2.0 * b_2) / a;
	elseif (b_2 <= 2.32e-209)
		tmp = sqrt((-c / a));
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -4.2e-218], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], If[LessEqual[b$95$2, 2.32e-209], N[Sqrt[N[((-c) / a), $MachinePrecision]], $MachinePrecision], N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -4.2 \cdot 10^{-218}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{elif}\;b\_2 \leq 2.32 \cdot 10^{-209}:\\
\;\;\;\;\sqrt{\frac{-c}{a}}\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -4.19999999999999988e-218

    1. Initial program 70.3%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6476.1

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites76.1%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -4.19999999999999988e-218 < b_2 < 2.32000000000000005e-209

    1. Initial program 67.6%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around inf

      \[\leadsto \color{blue}{\sqrt{\frac{c}{a}} \cdot \sqrt{-1}} \]
    4. Step-by-step derivation
      1. sqrt-unprodN/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      2. lower-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      3. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      4. lower-/.f6458.7

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
    5. Applied rewrites58.7%

      \[\leadsto \color{blue}{\sqrt{\frac{c}{a} \cdot -1}} \]
    6. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{c}{a} \cdot -1} \]
      3. *-commutativeN/A

        \[\leadsto \sqrt{-1 \cdot \frac{c}{a}} \]
      4. associate-*r/N/A

        \[\leadsto \sqrt{\frac{-1 \cdot c}{a}} \]
      5. mul-1-negN/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(c\right)}{a}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{neg}\left(c\right)}{a}} \]
      7. lower-neg.f6458.7

        \[\leadsto \sqrt{\frac{-c}{a}} \]
    7. Applied rewrites58.7%

      \[\leadsto \color{blue}{\sqrt{\frac{-c}{a}}} \]

    if 2.32000000000000005e-209 < b_2

    1. Initial program 25.7%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6477.3

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites77.3%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 6: 67.9% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{c}{b\_2} \cdot -0.5\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -5e-310) (/ (* -2.0 b_2) a) (* (/ c b_2) -0.5)))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -5e-310) {
		tmp = (-2.0 * b_2) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    real(8) :: tmp
    if (b_2 <= (-5d-310)) then
        tmp = ((-2.0d0) * b_2) / a
    else
        tmp = (c / b_2) * (-0.5d0)
    end if
    code = tmp
end function
public static double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -5e-310) {
		tmp = (-2.0 * b_2) / a;
	} else {
		tmp = (c / b_2) * -0.5;
	}
	return tmp;
}
def code(a, b_2, c):
	tmp = 0
	if b_2 <= -5e-310:
		tmp = (-2.0 * b_2) / a
	else:
		tmp = (c / b_2) * -0.5
	return tmp
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -5e-310)
		tmp = Float64(Float64(-2.0 * b_2) / a);
	else
		tmp = Float64(Float64(c / b_2) * -0.5);
	end
	return tmp
end
function tmp_2 = code(a, b_2, c)
	tmp = 0.0;
	if (b_2 <= -5e-310)
		tmp = (-2.0 * b_2) / a;
	else
		tmp = (c / b_2) * -0.5;
	end
	tmp_2 = tmp;
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -5e-310], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision], N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{c}{b\_2} \cdot -0.5\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if b_2 < -4.999999999999985e-310

    1. Initial program 71.2%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    4. Step-by-step derivation
      1. lower-*.f6468.7

        \[\leadsto \frac{-2 \cdot \color{blue}{b\_2}}{a} \]
    5. Applied rewrites68.7%

      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]

    if -4.999999999999985e-310 < b_2

    1. Initial program 26.8%

      \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in a around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      2. lower-*.f64N/A

        \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
      3. lower-/.f6473.2

        \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
    5. Applied rewrites73.2%

      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 7: 34.6% accurate, 2.4× speedup?

\[\begin{array}{l} \\ \frac{c}{b\_2} \cdot -0.5 \end{array} \]
(FPCore (a b_2 c) :precision binary64 (* (/ c b_2) -0.5))
double code(double a, double b_2, double c) {
	return (c / b_2) * -0.5;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(a, b_2, c)
use fmin_fmax_functions
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (c / b_2) * (-0.5d0)
end function
public static double code(double a, double b_2, double c) {
	return (c / b_2) * -0.5;
}
def code(a, b_2, c):
	return (c / b_2) * -0.5
function code(a, b_2, c)
	return Float64(Float64(c / b_2) * -0.5)
end
function tmp = code(a, b_2, c)
	tmp = (c / b_2) * -0.5;
end
code[a_, b$95$2_, c_] := N[(N[(c / b$95$2), $MachinePrecision] * -0.5), $MachinePrecision]
\begin{array}{l}

\\
\frac{c}{b\_2} \cdot -0.5
\end{array}
Derivation
  1. Initial program 50.2%

    \[\frac{\left(-b\_2\right) + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
  2. Add Preprocessing
  3. Taylor expanded in a around 0

    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
  4. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
    2. lower-*.f64N/A

      \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{\frac{-1}{2}} \]
    3. lower-/.f6435.8

      \[\leadsto \frac{c}{b\_2} \cdot -0.5 \]
  5. Applied rewrites35.8%

    \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot -0.5} \]
  6. Add Preprocessing

Developer Target 1: 99.6% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\ t_1 := \begin{array}{l} \mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\ \;\;\;\;\sqrt{\left|b\_2\right| - t\_0} \cdot \sqrt{\left|b\_2\right| + t\_0}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{hypot}\left(b\_2, t\_0\right)\\ \end{array}\\ \mathbf{if}\;b\_2 < 0:\\ \;\;\;\;\frac{t\_1 - b\_2}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-c}{b\_2 + t\_1}\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (let* ((t_0 (* (sqrt (fabs a)) (sqrt (fabs c))))
        (t_1
         (if (== (copysign a c) a)
           (* (sqrt (- (fabs b_2) t_0)) (sqrt (+ (fabs b_2) t_0)))
           (hypot b_2 t_0))))
   (if (< b_2 0.0) (/ (- t_1 b_2) a) (/ (- c) (+ b_2 t_1)))))
double code(double a, double b_2, double c) {
	double t_0 = sqrt(fabs(a)) * sqrt(fabs(c));
	double tmp;
	if (copysign(a, c) == a) {
		tmp = sqrt((fabs(b_2) - t_0)) * sqrt((fabs(b_2) + t_0));
	} else {
		tmp = hypot(b_2, t_0);
	}
	double t_1 = tmp;
	double tmp_1;
	if (b_2 < 0.0) {
		tmp_1 = (t_1 - b_2) / a;
	} else {
		tmp_1 = -c / (b_2 + t_1);
	}
	return tmp_1;
}
public static double code(double a, double b_2, double c) {
	double t_0 = Math.sqrt(Math.abs(a)) * Math.sqrt(Math.abs(c));
	double tmp;
	if (Math.copySign(a, c) == a) {
		tmp = Math.sqrt((Math.abs(b_2) - t_0)) * Math.sqrt((Math.abs(b_2) + t_0));
	} else {
		tmp = Math.hypot(b_2, t_0);
	}
	double t_1 = tmp;
	double tmp_1;
	if (b_2 < 0.0) {
		tmp_1 = (t_1 - b_2) / a;
	} else {
		tmp_1 = -c / (b_2 + t_1);
	}
	return tmp_1;
}
def code(a, b_2, c):
	t_0 = math.sqrt(math.fabs(a)) * math.sqrt(math.fabs(c))
	tmp = 0
	if math.copysign(a, c) == a:
		tmp = math.sqrt((math.fabs(b_2) - t_0)) * math.sqrt((math.fabs(b_2) + t_0))
	else:
		tmp = math.hypot(b_2, t_0)
	t_1 = tmp
	tmp_1 = 0
	if b_2 < 0.0:
		tmp_1 = (t_1 - b_2) / a
	else:
		tmp_1 = -c / (b_2 + t_1)
	return tmp_1
function code(a, b_2, c)
	t_0 = Float64(sqrt(abs(a)) * sqrt(abs(c)))
	tmp = 0.0
	if (copysign(a, c) == a)
		tmp = Float64(sqrt(Float64(abs(b_2) - t_0)) * sqrt(Float64(abs(b_2) + t_0)));
	else
		tmp = hypot(b_2, t_0);
	end
	t_1 = tmp
	tmp_1 = 0.0
	if (b_2 < 0.0)
		tmp_1 = Float64(Float64(t_1 - b_2) / a);
	else
		tmp_1 = Float64(Float64(-c) / Float64(b_2 + t_1));
	end
	return tmp_1
end
function tmp_3 = code(a, b_2, c)
	t_0 = sqrt(abs(a)) * sqrt(abs(c));
	tmp = 0.0;
	if ((sign(c) * abs(a)) == a)
		tmp = sqrt((abs(b_2) - t_0)) * sqrt((abs(b_2) + t_0));
	else
		tmp = hypot(b_2, t_0);
	end
	t_1 = tmp;
	tmp_2 = 0.0;
	if (b_2 < 0.0)
		tmp_2 = (t_1 - b_2) / a;
	else
		tmp_2 = -c / (b_2 + t_1);
	end
	tmp_3 = tmp_2;
end
code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(N[Sqrt[N[Abs[a], $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[Abs[c], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = If[Equal[N[With[{TMP1 = Abs[a], TMP2 = Sign[c]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision], a], N[(N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[b$95$2 ^ 2 + t$95$0 ^ 2], $MachinePrecision]]}, If[Less[b$95$2, 0.0], N[(N[(t$95$1 - b$95$2), $MachinePrecision] / a), $MachinePrecision], N[((-c) / N[(b$95$2 + t$95$1), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\
t_1 := \begin{array}{l}
\mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\
\;\;\;\;\sqrt{\left|b\_2\right| - t\_0} \cdot \sqrt{\left|b\_2\right| + t\_0}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{hypot}\left(b\_2, t\_0\right)\\


\end{array}\\
\mathbf{if}\;b\_2 < 0:\\
\;\;\;\;\frac{t\_1 - b\_2}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{-c}{b\_2 + t\_1}\\


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2025064 
(FPCore (a b_2 c)
  :name "quad2p (problem 3.2.1, positive)"
  :precision binary64
  :herbie-expected 10

  :alt
  (! :herbie-platform default (let ((sqtD (let ((x (* (sqrt (fabs a)) (sqrt (fabs c))))) (if (== (copysign a c) a) (* (sqrt (- (fabs b_2) x)) (sqrt (+ (fabs b_2) x))) (hypot b_2 x))))) (if (< b_2 0) (/ (- sqtD b_2) a) (/ (- c) (+ b_2 sqtD)))))

  (/ (+ (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))