1/2(abs(p)+abs(r) - sqrt((p-r)^2 + 4q^2))

Percentage Accurate: 24.4% → 62.6%
Time: 5.0s
Alternatives: 5
Speedup: 83.3×

Specification

?
\[\begin{array}{l} \\ \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \end{array} \]
(FPCore (p r q)
 :precision binary64
 (*
  (/ 1.0 2.0)
  (- (+ (fabs p) (fabs r)) (sqrt (+ (pow (- p r) 2.0) (* 4.0 (pow q 2.0)))))))
double code(double p, double r, double q) {
	return (1.0 / 2.0) * ((fabs(p) + fabs(r)) - sqrt((pow((p - r), 2.0) + (4.0 * pow(q, 2.0)))));
}
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(p, r, q)
use fmin_fmax_functions
    real(8), intent (in) :: p
    real(8), intent (in) :: r
    real(8), intent (in) :: q
    code = (1.0d0 / 2.0d0) * ((abs(p) + abs(r)) - sqrt((((p - r) ** 2.0d0) + (4.0d0 * (q ** 2.0d0)))))
end function
public static double code(double p, double r, double q) {
	return (1.0 / 2.0) * ((Math.abs(p) + Math.abs(r)) - Math.sqrt((Math.pow((p - r), 2.0) + (4.0 * Math.pow(q, 2.0)))));
}
def code(p, r, q):
	return (1.0 / 2.0) * ((math.fabs(p) + math.fabs(r)) - math.sqrt((math.pow((p - r), 2.0) + (4.0 * math.pow(q, 2.0)))))
function code(p, r, q)
	return Float64(Float64(1.0 / 2.0) * Float64(Float64(abs(p) + abs(r)) - sqrt(Float64((Float64(p - r) ^ 2.0) + Float64(4.0 * (q ^ 2.0))))))
end
function tmp = code(p, r, q)
	tmp = (1.0 / 2.0) * ((abs(p) + abs(r)) - sqrt((((p - r) ^ 2.0) + (4.0 * (q ^ 2.0)))));
end
code[p_, r_, q_] := N[(N[(1.0 / 2.0), $MachinePrecision] * N[(N[(N[Abs[p], $MachinePrecision] + N[Abs[r], $MachinePrecision]), $MachinePrecision] - N[Sqrt[N[(N[Power[N[(p - r), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[Power[q, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right)
\end{array}

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 5 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: 24.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \end{array} \]
(FPCore (p r q)
 :precision binary64
 (*
  (/ 1.0 2.0)
  (- (+ (fabs p) (fabs r)) (sqrt (+ (pow (- p r) 2.0) (* 4.0 (pow q 2.0)))))))
double code(double p, double r, double q) {
	return (1.0 / 2.0) * ((fabs(p) + fabs(r)) - sqrt((pow((p - r), 2.0) + (4.0 * pow(q, 2.0)))));
}
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(p, r, q)
use fmin_fmax_functions
    real(8), intent (in) :: p
    real(8), intent (in) :: r
    real(8), intent (in) :: q
    code = (1.0d0 / 2.0d0) * ((abs(p) + abs(r)) - sqrt((((p - r) ** 2.0d0) + (4.0d0 * (q ** 2.0d0)))))
end function
public static double code(double p, double r, double q) {
	return (1.0 / 2.0) * ((Math.abs(p) + Math.abs(r)) - Math.sqrt((Math.pow((p - r), 2.0) + (4.0 * Math.pow(q, 2.0)))));
}
def code(p, r, q):
	return (1.0 / 2.0) * ((math.fabs(p) + math.fabs(r)) - math.sqrt((math.pow((p - r), 2.0) + (4.0 * math.pow(q, 2.0)))))
function code(p, r, q)
	return Float64(Float64(1.0 / 2.0) * Float64(Float64(abs(p) + abs(r)) - sqrt(Float64((Float64(p - r) ^ 2.0) + Float64(4.0 * (q ^ 2.0))))))
end
function tmp = code(p, r, q)
	tmp = (1.0 / 2.0) * ((abs(p) + abs(r)) - sqrt((((p - r) ^ 2.0) + (4.0 * (q ^ 2.0)))));
end
code[p_, r_, q_] := N[(N[(1.0 / 2.0), $MachinePrecision] * N[(N[(N[Abs[p], $MachinePrecision] + N[Abs[r], $MachinePrecision]), $MachinePrecision] - N[Sqrt[N[(N[Power[N[(p - r), $MachinePrecision], 2.0], $MachinePrecision] + N[(4.0 * N[Power[q, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right)
\end{array}

Alternative 1: 62.6% accurate, 3.3× speedup?

\[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;q\_m \leq 1.35 \cdot 10^{-82}:\\ \;\;\;\;0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)\\ \mathbf{elif}\;q\_m \leq 1.22 \cdot 10^{+141}:\\ \;\;\;\;\frac{-4 \cdot \left(q\_m \cdot q\_m\right)}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q\_m \cdot q\_m, 4, p \cdot p\right)}} \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
q_m = (fabs.f64 q)
NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
(FPCore (p r q_m)
 :precision binary64
 (if (<= q_m 1.35e-82)
   (* 0.5 (+ p (+ (- (fabs r) r) (fabs p))))
   (if (<= q_m 1.22e+141)
     (*
      (/
       (* -4.0 (* q_m q_m))
       (+ (+ (fabs r) (fabs p)) (sqrt (fma (* q_m q_m) 4.0 (* p p)))))
      0.5)
     (- q_m))))
q_m = fabs(q);
assert(p < r && r < q_m);
double code(double p, double r, double q_m) {
	double tmp;
	if (q_m <= 1.35e-82) {
		tmp = 0.5 * (p + ((fabs(r) - r) + fabs(p)));
	} else if (q_m <= 1.22e+141) {
		tmp = ((-4.0 * (q_m * q_m)) / ((fabs(r) + fabs(p)) + sqrt(fma((q_m * q_m), 4.0, (p * p))))) * 0.5;
	} else {
		tmp = -q_m;
	}
	return tmp;
}
q_m = abs(q)
p, r, q_m = sort([p, r, q_m])
function code(p, r, q_m)
	tmp = 0.0
	if (q_m <= 1.35e-82)
		tmp = Float64(0.5 * Float64(p + Float64(Float64(abs(r) - r) + abs(p))));
	elseif (q_m <= 1.22e+141)
		tmp = Float64(Float64(Float64(-4.0 * Float64(q_m * q_m)) / Float64(Float64(abs(r) + abs(p)) + sqrt(fma(Float64(q_m * q_m), 4.0, Float64(p * p))))) * 0.5);
	else
		tmp = Float64(-q_m);
	end
	return tmp
end
q_m = N[Abs[q], $MachinePrecision]
NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
code[p_, r_, q$95$m_] := If[LessEqual[q$95$m, 1.35e-82], N[(0.5 * N[(p + N[(N[(N[Abs[r], $MachinePrecision] - r), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[q$95$m, 1.22e+141], N[(N[(N[(-4.0 * N[(q$95$m * q$95$m), $MachinePrecision]), $MachinePrecision] / N[(N[(N[Abs[r], $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + N[Sqrt[N[(N[(q$95$m * q$95$m), $MachinePrecision] * 4.0 + N[(p * p), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision], (-q$95$m)]]
\begin{array}{l}
q_m = \left|q\right|
\\
[p, r, q_m] = \mathsf{sort}([p, r, q_m])\\
\\
\begin{array}{l}
\mathbf{if}\;q\_m \leq 1.35 \cdot 10^{-82}:\\
\;\;\;\;0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)\\

\mathbf{elif}\;q\_m \leq 1.22 \cdot 10^{+141}:\\
\;\;\;\;\frac{-4 \cdot \left(q\_m \cdot q\_m\right)}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q\_m \cdot q\_m, 4, p \cdot p\right)}} \cdot 0.5\\

\mathbf{else}:\\
\;\;\;\;-q\_m\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if q < 1.3500000000000001e-82

    1. Initial program 24.3%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in p around -inf

      \[\leadsto \color{blue}{-1 \cdot \left(p \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)\right)} \]
    3. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto -1 \cdot \left(p \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{\color{blue}{2}}\right)\right) \]
      2. associate-*r*N/A

        \[\leadsto \left(-1 \cdot p\right) \cdot \color{blue}{\left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)} \]
      3. mul-1-negN/A

        \[\leadsto \left(\mathsf{neg}\left(p\right)\right) \cdot \left(\color{blue}{\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p}} - \frac{1}{2}\right) \]
      4. lower-*.f64N/A

        \[\leadsto \left(\mathsf{neg}\left(p\right)\right) \cdot \color{blue}{\left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)} \]
      5. lower-neg.f64N/A

        \[\leadsto \left(-p\right) \cdot \left(\color{blue}{\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p}} - \frac{1}{2}\right) \]
      6. lower--.f64N/A

        \[\leadsto \left(-p\right) \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \color{blue}{\frac{1}{2}}\right) \]
    4. Applied rewrites66.0%

      \[\leadsto \color{blue}{\left(-p\right) \cdot \left(\frac{\left|p\right| + \left(\left|r\right| - r\right)}{p} \cdot -0.5 - 0.5\right)} \]
    5. Taylor expanded in p around 0

      \[\leadsto \frac{1}{2} \cdot p + \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right)} \]
    6. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot p + \frac{1}{2} \cdot \left(\left(\color{blue}{\left|p\right|} + \left|r\right|\right) - r\right) \]
      2. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot p + \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right) \]
      3. distribute-lft-outN/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - r\right)}\right) \]
      4. lower-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - r\right)}\right) \]
      5. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\color{blue}{\left(\left|p\right| + \left|r\right|\right)} - r\right)\right) \]
      6. associate-+r-N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left|p\right| + \left(\left|r\right| - \color{blue}{r}\right)\right)\right) \]
      7. lower-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left|p\right| + \color{blue}{\left(\left|r\right| - r\right)}\right)\right) \]
      8. +-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
      9. lower-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
      10. lift-fabs.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
      11. lift--.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
      12. lift-fabs.f6466.0

        \[\leadsto 0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
    7. Applied rewrites66.0%

      \[\leadsto 0.5 \cdot \color{blue}{\left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)} \]

    if 1.3500000000000001e-82 < q < 1.2199999999999999e141

    1. Initial program 34.0%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in r around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}}\right)} \]
    3. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\left(\left|p\right| + \left|r\right|\right)} - \sqrt{4 \cdot {q}^{2} + {p}^{2}}\right) \]
      2. *-commutativeN/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}}\right) \cdot \color{blue}{\frac{1}{2}} \]
      3. lower-*.f64N/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}}\right) \cdot \color{blue}{\frac{1}{2}} \]
    4. Applied rewrites33.0%

      \[\leadsto \color{blue}{\left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot 0.5} \]
    5. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      2. lift-+.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      3. lift-fabs.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      4. lift-fabs.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      5. lift-sqrt.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      6. lift-*.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      7. lift-*.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}\right) \cdot \frac{1}{2} \]
      8. lift-fma.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \sqrt{\left(q \cdot q\right) \cdot 4 + p \cdot p}\right) \cdot \frac{1}{2} \]
      9. +-commutativeN/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{\left(q \cdot q\right) \cdot 4 + p \cdot p}\right) \cdot \frac{1}{2} \]
      10. pow2N/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{q}^{2} \cdot 4 + p \cdot p}\right) \cdot \frac{1}{2} \]
      11. *-commutativeN/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + p \cdot p}\right) \cdot \frac{1}{2} \]
      12. pow2N/A

        \[\leadsto \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}}\right) \cdot \frac{1}{2} \]
      13. flip--N/A

        \[\leadsto \frac{\left(\left|p\right| + \left|r\right|\right) \cdot \left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}} \cdot \sqrt{4 \cdot {q}^{2} + {p}^{2}}}{\left(\left|p\right| + \left|r\right|\right) + \sqrt{4 \cdot {q}^{2} + {p}^{2}}} \cdot \frac{1}{2} \]
      14. lower-/.f64N/A

        \[\leadsto \frac{\left(\left|p\right| + \left|r\right|\right) \cdot \left(\left|p\right| + \left|r\right|\right) - \sqrt{4 \cdot {q}^{2} + {p}^{2}} \cdot \sqrt{4 \cdot {q}^{2} + {p}^{2}}}{\left(\left|p\right| + \left|r\right|\right) + \sqrt{4 \cdot {q}^{2} + {p}^{2}}} \cdot \frac{1}{2} \]
    6. Applied rewrites32.5%

      \[\leadsto \frac{\left(\left|r\right| + \left|p\right|\right) \cdot \left(\left|r\right| + \left|p\right|\right) - \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)} \cdot \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot 0.5 \]
    7. Taylor expanded in q around inf

      \[\leadsto \frac{-4 \cdot {q}^{2}}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot \frac{1}{2} \]
    8. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \frac{-4 \cdot {q}^{2}}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot \frac{1}{2} \]
      2. pow2N/A

        \[\leadsto \frac{-4 \cdot \left(q \cdot q\right)}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot \frac{1}{2} \]
      3. lift-*.f6451.1

        \[\leadsto \frac{-4 \cdot \left(q \cdot q\right)}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot 0.5 \]
    9. Applied rewrites51.1%

      \[\leadsto \frac{-4 \cdot \left(q \cdot q\right)}{\left(\left|r\right| + \left|p\right|\right) + \sqrt{\mathsf{fma}\left(q \cdot q, 4, p \cdot p\right)}} \cdot 0.5 \]

    if 1.2199999999999999e141 < q

    1. Initial program 11.0%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in q around inf

      \[\leadsto \color{blue}{-1 \cdot q} \]
    3. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{neg}\left(q\right) \]
      2. lower-neg.f6474.3

        \[\leadsto -q \]
    4. Applied rewrites74.3%

      \[\leadsto \color{blue}{-q} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 2: 40.1% accurate, 2.0× speedup?

\[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;4 \cdot {q\_m}^{2} \leq 3 \cdot 10^{-151}:\\ \;\;\;\;\left(\left(\left|r\right| + \left|p\right|\right) - r\right) \cdot 0.5\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
q_m = (fabs.f64 q)
NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
(FPCore (p r q_m)
 :precision binary64
 (if (<= (* 4.0 (pow q_m 2.0)) 3e-151)
   (* (- (+ (fabs r) (fabs p)) r) 0.5)
   (- q_m)))
q_m = fabs(q);
assert(p < r && r < q_m);
double code(double p, double r, double q_m) {
	double tmp;
	if ((4.0 * pow(q_m, 2.0)) <= 3e-151) {
		tmp = ((fabs(r) + fabs(p)) - r) * 0.5;
	} else {
		tmp = -q_m;
	}
	return tmp;
}
q_m =     private
NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
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(p, r, q_m)
use fmin_fmax_functions
    real(8), intent (in) :: p
    real(8), intent (in) :: r
    real(8), intent (in) :: q_m
    real(8) :: tmp
    if ((4.0d0 * (q_m ** 2.0d0)) <= 3d-151) then
        tmp = ((abs(r) + abs(p)) - r) * 0.5d0
    else
        tmp = -q_m
    end if
    code = tmp
end function
q_m = Math.abs(q);
assert p < r && r < q_m;
public static double code(double p, double r, double q_m) {
	double tmp;
	if ((4.0 * Math.pow(q_m, 2.0)) <= 3e-151) {
		tmp = ((Math.abs(r) + Math.abs(p)) - r) * 0.5;
	} else {
		tmp = -q_m;
	}
	return tmp;
}
q_m = math.fabs(q)
[p, r, q_m] = sort([p, r, q_m])
def code(p, r, q_m):
	tmp = 0
	if (4.0 * math.pow(q_m, 2.0)) <= 3e-151:
		tmp = ((math.fabs(r) + math.fabs(p)) - r) * 0.5
	else:
		tmp = -q_m
	return tmp
q_m = abs(q)
p, r, q_m = sort([p, r, q_m])
function code(p, r, q_m)
	tmp = 0.0
	if (Float64(4.0 * (q_m ^ 2.0)) <= 3e-151)
		tmp = Float64(Float64(Float64(abs(r) + abs(p)) - r) * 0.5);
	else
		tmp = Float64(-q_m);
	end
	return tmp
end
q_m = abs(q);
p, r, q_m = num2cell(sort([p, r, q_m])){:}
function tmp_2 = code(p, r, q_m)
	tmp = 0.0;
	if ((4.0 * (q_m ^ 2.0)) <= 3e-151)
		tmp = ((abs(r) + abs(p)) - r) * 0.5;
	else
		tmp = -q_m;
	end
	tmp_2 = tmp;
end
q_m = N[Abs[q], $MachinePrecision]
NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
code[p_, r_, q$95$m_] := If[LessEqual[N[(4.0 * N[Power[q$95$m, 2.0], $MachinePrecision]), $MachinePrecision], 3e-151], N[(N[(N[(N[Abs[r], $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] - r), $MachinePrecision] * 0.5), $MachinePrecision], (-q$95$m)]
\begin{array}{l}
q_m = \left|q\right|
\\
[p, r, q_m] = \mathsf{sort}([p, r, q_m])\\
\\
\begin{array}{l}
\mathbf{if}\;4 \cdot {q\_m}^{2} \leq 3 \cdot 10^{-151}:\\
\;\;\;\;\left(\left(\left|r\right| + \left|p\right|\right) - r\right) \cdot 0.5\\

\mathbf{else}:\\
\;\;\;\;-q\_m\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 #s(literal 4 binary64) (pow.f64 q #s(literal 2 binary64))) < 3e-151

    1. Initial program 24.2%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in r around -inf

      \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \color{blue}{-1 \cdot r}\right) \]
    3. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \left(\mathsf{neg}\left(r\right)\right)\right) \]
      2. lower-neg.f643.5

        \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \left(-r\right)\right) \]
    4. Applied rewrites3.5%

      \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \color{blue}{\left(-r\right)}\right) \]
    5. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \left(-r\right)\right)} \]
      2. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2}} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \left(-r\right)\right) \]
      3. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - \left(-r\right)\right) \cdot \frac{1}{2}} \]
      4. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - \left(-r\right)\right) \cdot \frac{1}{2}} \]
      5. lift-+.f64N/A

        \[\leadsto \left(\color{blue}{\left(\left|p\right| + \left|r\right|\right)} - \left(-r\right)\right) \cdot \frac{1}{2} \]
      6. lift-fabs.f64N/A

        \[\leadsto \left(\left(\color{blue}{\left|p\right|} + \left|r\right|\right) - \left(-r\right)\right) \cdot \frac{1}{2} \]
      7. lift-fabs.f64N/A

        \[\leadsto \left(\left(\left|p\right| + \color{blue}{\left|r\right|}\right) - \left(-r\right)\right) \cdot \frac{1}{2} \]
      8. +-commutativeN/A

        \[\leadsto \left(\color{blue}{\left(\left|r\right| + \left|p\right|\right)} - \left(-r\right)\right) \cdot \frac{1}{2} \]
      9. lift-fabs.f64N/A

        \[\leadsto \left(\left(\color{blue}{\left|r\right|} + \left|p\right|\right) - \left(-r\right)\right) \cdot \frac{1}{2} \]
      10. lift-fabs.f64N/A

        \[\leadsto \left(\left(\left|r\right| + \color{blue}{\left|p\right|}\right) - \left(-r\right)\right) \cdot \frac{1}{2} \]
      11. lift-+.f64N/A

        \[\leadsto \left(\color{blue}{\left(\left|r\right| + \left|p\right|\right)} - \left(-r\right)\right) \cdot \frac{1}{2} \]
      12. metadata-eval3.5

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \left(-r\right)\right) \cdot \color{blue}{0.5} \]
    6. Applied rewrites3.5%

      \[\leadsto \color{blue}{\left(\left(\left|r\right| + \left|p\right|\right) - \left(-r\right)\right) \cdot 0.5} \]
    7. Taylor expanded in r around inf

      \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \color{blue}{r}\right) \cdot \frac{1}{2} \]
    8. Step-by-step derivation
      1. Applied rewrites22.2%

        \[\leadsto \left(\left(\left|r\right| + \left|p\right|\right) - \color{blue}{r}\right) \cdot 0.5 \]

      if 3e-151 < (*.f64 #s(literal 4 binary64) (pow.f64 q #s(literal 2 binary64)))

      1. Initial program 24.5%

        \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
      2. Taylor expanded in q around inf

        \[\leadsto \color{blue}{-1 \cdot q} \]
      3. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \mathsf{neg}\left(q\right) \]
        2. lower-neg.f6450.6

          \[\leadsto -q \]
      4. Applied rewrites50.6%

        \[\leadsto \color{blue}{-q} \]
    9. Recombined 2 regimes into one program.
    10. Add Preprocessing

    Alternative 3: 57.1% accurate, 10.0× speedup?

    \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;q\_m \leq 7.2 \cdot 10^{-24}:\\ \;\;\;\;0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
    q_m = (fabs.f64 q)
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    (FPCore (p r q_m)
     :precision binary64
     (if (<= q_m 7.2e-24) (* 0.5 (+ p (+ (- (fabs r) r) (fabs p)))) (- q_m)))
    q_m = fabs(q);
    assert(p < r && r < q_m);
    double code(double p, double r, double q_m) {
    	double tmp;
    	if (q_m <= 7.2e-24) {
    		tmp = 0.5 * (p + ((fabs(r) - r) + fabs(p)));
    	} else {
    		tmp = -q_m;
    	}
    	return tmp;
    }
    
    q_m =     private
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    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(p, r, q_m)
    use fmin_fmax_functions
        real(8), intent (in) :: p
        real(8), intent (in) :: r
        real(8), intent (in) :: q_m
        real(8) :: tmp
        if (q_m <= 7.2d-24) then
            tmp = 0.5d0 * (p + ((abs(r) - r) + abs(p)))
        else
            tmp = -q_m
        end if
        code = tmp
    end function
    
    q_m = Math.abs(q);
    assert p < r && r < q_m;
    public static double code(double p, double r, double q_m) {
    	double tmp;
    	if (q_m <= 7.2e-24) {
    		tmp = 0.5 * (p + ((Math.abs(r) - r) + Math.abs(p)));
    	} else {
    		tmp = -q_m;
    	}
    	return tmp;
    }
    
    q_m = math.fabs(q)
    [p, r, q_m] = sort([p, r, q_m])
    def code(p, r, q_m):
    	tmp = 0
    	if q_m <= 7.2e-24:
    		tmp = 0.5 * (p + ((math.fabs(r) - r) + math.fabs(p)))
    	else:
    		tmp = -q_m
    	return tmp
    
    q_m = abs(q)
    p, r, q_m = sort([p, r, q_m])
    function code(p, r, q_m)
    	tmp = 0.0
    	if (q_m <= 7.2e-24)
    		tmp = Float64(0.5 * Float64(p + Float64(Float64(abs(r) - r) + abs(p))));
    	else
    		tmp = Float64(-q_m);
    	end
    	return tmp
    end
    
    q_m = abs(q);
    p, r, q_m = num2cell(sort([p, r, q_m])){:}
    function tmp_2 = code(p, r, q_m)
    	tmp = 0.0;
    	if (q_m <= 7.2e-24)
    		tmp = 0.5 * (p + ((abs(r) - r) + abs(p)));
    	else
    		tmp = -q_m;
    	end
    	tmp_2 = tmp;
    end
    
    q_m = N[Abs[q], $MachinePrecision]
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    code[p_, r_, q$95$m_] := If[LessEqual[q$95$m, 7.2e-24], N[(0.5 * N[(p + N[(N[(N[Abs[r], $MachinePrecision] - r), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], (-q$95$m)]
    
    \begin{array}{l}
    q_m = \left|q\right|
    \\
    [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\
    \\
    \begin{array}{l}
    \mathbf{if}\;q\_m \leq 7.2 \cdot 10^{-24}:\\
    \;\;\;\;0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;-q\_m\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if q < 7.2000000000000002e-24

      1. Initial program 24.0%

        \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
      2. Taylor expanded in p around -inf

        \[\leadsto \color{blue}{-1 \cdot \left(p \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)\right)} \]
      3. Step-by-step derivation
        1. metadata-evalN/A

          \[\leadsto -1 \cdot \left(p \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{\color{blue}{2}}\right)\right) \]
        2. associate-*r*N/A

          \[\leadsto \left(-1 \cdot p\right) \cdot \color{blue}{\left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)} \]
        3. mul-1-negN/A

          \[\leadsto \left(\mathsf{neg}\left(p\right)\right) \cdot \left(\color{blue}{\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p}} - \frac{1}{2}\right) \]
        4. lower-*.f64N/A

          \[\leadsto \left(\mathsf{neg}\left(p\right)\right) \cdot \color{blue}{\left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \frac{1}{2}\right)} \]
        5. lower-neg.f64N/A

          \[\leadsto \left(-p\right) \cdot \left(\color{blue}{\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p}} - \frac{1}{2}\right) \]
        6. lower--.f64N/A

          \[\leadsto \left(-p\right) \cdot \left(\frac{-1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - r}{p} - \color{blue}{\frac{1}{2}}\right) \]
      4. Applied rewrites58.7%

        \[\leadsto \color{blue}{\left(-p\right) \cdot \left(\frac{\left|p\right| + \left(\left|r\right| - r\right)}{p} \cdot -0.5 - 0.5\right)} \]
      5. Taylor expanded in p around 0

        \[\leadsto \frac{1}{2} \cdot p + \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right)} \]
      6. Step-by-step derivation
        1. metadata-evalN/A

          \[\leadsto \frac{1}{2} \cdot p + \frac{1}{2} \cdot \left(\left(\color{blue}{\left|p\right|} + \left|r\right|\right) - r\right) \]
        2. metadata-evalN/A

          \[\leadsto \frac{1}{2} \cdot p + \frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right) \]
        3. distribute-lft-outN/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - r\right)}\right) \]
        4. lower-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \color{blue}{\left(\left(\left|p\right| + \left|r\right|\right) - r\right)}\right) \]
        5. metadata-evalN/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\color{blue}{\left(\left|p\right| + \left|r\right|\right)} - r\right)\right) \]
        6. associate-+r-N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left|p\right| + \left(\left|r\right| - \color{blue}{r}\right)\right)\right) \]
        7. lower-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left|p\right| + \color{blue}{\left(\left|r\right| - r\right)}\right)\right) \]
        8. +-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
        9. lower-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
        10. lift-fabs.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
        11. lift--.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
        12. lift-fabs.f6458.7

          \[\leadsto 0.5 \cdot \left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right) \]
      7. Applied rewrites58.7%

        \[\leadsto 0.5 \cdot \color{blue}{\left(p + \left(\left(\left|r\right| - r\right) + \left|p\right|\right)\right)} \]

      if 7.2000000000000002e-24 < q

      1. Initial program 24.7%

        \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
      2. Taylor expanded in q around inf

        \[\leadsto \color{blue}{-1 \cdot q} \]
      3. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \mathsf{neg}\left(q\right) \]
        2. lower-neg.f6455.7

          \[\leadsto -q \]
      4. Applied rewrites55.7%

        \[\leadsto \color{blue}{-q} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 4: 35.3% accurate, 83.3× speedup?

    \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ -q\_m \end{array} \]
    q_m = (fabs.f64 q)
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    (FPCore (p r q_m) :precision binary64 (- q_m))
    q_m = fabs(q);
    assert(p < r && r < q_m);
    double code(double p, double r, double q_m) {
    	return -q_m;
    }
    
    q_m =     private
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    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(p, r, q_m)
    use fmin_fmax_functions
        real(8), intent (in) :: p
        real(8), intent (in) :: r
        real(8), intent (in) :: q_m
        code = -q_m
    end function
    
    q_m = Math.abs(q);
    assert p < r && r < q_m;
    public static double code(double p, double r, double q_m) {
    	return -q_m;
    }
    
    q_m = math.fabs(q)
    [p, r, q_m] = sort([p, r, q_m])
    def code(p, r, q_m):
    	return -q_m
    
    q_m = abs(q)
    p, r, q_m = sort([p, r, q_m])
    function code(p, r, q_m)
    	return Float64(-q_m)
    end
    
    q_m = abs(q);
    p, r, q_m = num2cell(sort([p, r, q_m])){:}
    function tmp = code(p, r, q_m)
    	tmp = -q_m;
    end
    
    q_m = N[Abs[q], $MachinePrecision]
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    code[p_, r_, q$95$m_] := (-q$95$m)
    
    \begin{array}{l}
    q_m = \left|q\right|
    \\
    [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\
    \\
    -q\_m
    \end{array}
    
    Derivation
    1. Initial program 24.4%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in q around inf

      \[\leadsto \color{blue}{-1 \cdot q} \]
    3. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{neg}\left(q\right) \]
      2. lower-neg.f6435.3

        \[\leadsto -q \]
    4. Applied rewrites35.3%

      \[\leadsto \color{blue}{-q} \]
    5. Add Preprocessing

    Alternative 5: 3.3% accurate, 250.0× speedup?

    \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ q\_m \end{array} \]
    q_m = (fabs.f64 q)
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    (FPCore (p r q_m) :precision binary64 q_m)
    q_m = fabs(q);
    assert(p < r && r < q_m);
    double code(double p, double r, double q_m) {
    	return q_m;
    }
    
    q_m =     private
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    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(p, r, q_m)
    use fmin_fmax_functions
        real(8), intent (in) :: p
        real(8), intent (in) :: r
        real(8), intent (in) :: q_m
        code = q_m
    end function
    
    q_m = Math.abs(q);
    assert p < r && r < q_m;
    public static double code(double p, double r, double q_m) {
    	return q_m;
    }
    
    q_m = math.fabs(q)
    [p, r, q_m] = sort([p, r, q_m])
    def code(p, r, q_m):
    	return q_m
    
    q_m = abs(q)
    p, r, q_m = sort([p, r, q_m])
    function code(p, r, q_m)
    	return q_m
    end
    
    q_m = abs(q);
    p, r, q_m = num2cell(sort([p, r, q_m])){:}
    function tmp = code(p, r, q_m)
    	tmp = q_m;
    end
    
    q_m = N[Abs[q], $MachinePrecision]
    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
    code[p_, r_, q$95$m_] := q$95$m
    
    \begin{array}{l}
    q_m = \left|q\right|
    \\
    [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\
    \\
    q\_m
    \end{array}
    
    Derivation
    1. Initial program 24.4%

      \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
    2. Taylor expanded in q around -inf

      \[\leadsto \color{blue}{q} \]
    3. Step-by-step derivation
      1. Applied rewrites3.3%

        \[\leadsto \color{blue}{q} \]
      2. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2025095 
      (FPCore (p r q)
        :name "1/2(abs(p)+abs(r) - sqrt((p-r)^2 + 4q^2))"
        :precision binary64
        (* (/ 1.0 2.0) (- (+ (fabs p) (fabs r)) (sqrt (+ (pow (- p r) 2.0) (* 4.0 (pow q 2.0)))))))