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

Percentage Accurate: 24.3% → 62.6%
Time: 10.2s
Alternatives: 6
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)))));
}
real(8) function code(p, r, q)
    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}

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 6 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: 24.3% 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)))));
}
real(8) function code(p, r, q)
    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, 0.8× speedup?

\[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;{q\_m}^{2} \leq 10^{+110}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{\sqrt{\mathsf{fma}\left(q\_m \cdot q\_m, 4, r \cdot r\right)} + \left|r\right|}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
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 (<= (pow q_m 2.0) 1e+110)
   (*
    (pow 2.0 -1.0)
    (+
     (fma 2.0 (* p (/ r (+ (fabs r) r))) (fabs p))
     (*
      -4.0
      (/ (* q_m q_m) (+ (sqrt (fma (* q_m q_m) 4.0 (* r r))) (fabs r))))))
   (- q_m)))
q_m = fabs(q);
assert(p < r && r < q_m);
double code(double p, double r, double q_m) {
	double tmp;
	if (pow(q_m, 2.0) <= 1e+110) {
		tmp = pow(2.0, -1.0) * (fma(2.0, (p * (r / (fabs(r) + r))), fabs(p)) + (-4.0 * ((q_m * q_m) / (sqrt(fma((q_m * q_m), 4.0, (r * r))) + fabs(r)))));
	} 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 ^ 2.0) <= 1e+110)
		tmp = Float64((2.0 ^ -1.0) * Float64(fma(2.0, Float64(p * Float64(r / Float64(abs(r) + r))), abs(p)) + Float64(-4.0 * Float64(Float64(q_m * q_m) / Float64(sqrt(fma(Float64(q_m * q_m), 4.0, Float64(r * r))) + abs(r))))));
	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[N[Power[q$95$m, 2.0], $MachinePrecision], 1e+110], N[(N[Power[2.0, -1.0], $MachinePrecision] * N[(N[(2.0 * N[(p * N[(r / N[(N[Abs[r], $MachinePrecision] + r), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + N[(-4.0 * N[(N[(q$95$m * q$95$m), $MachinePrecision] / N[(N[Sqrt[N[(N[(q$95$m * q$95$m), $MachinePrecision] * 4.0 + N[(r * r), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + N[Abs[r], $MachinePrecision]), $MachinePrecision]), $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}^{2} \leq 10^{+110}:\\
\;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{\sqrt{\mathsf{fma}\left(q\_m \cdot q\_m, 4, r \cdot r\right)} + \left|r\right|}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (pow.f64 q #s(literal 2 binary64)) < 1e110

    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. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

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

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

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

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

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

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(\left|r\right| \cdot \left|r\right| - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}} \cdot \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}, \frac{1}{\left|r\right| + \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}}, \left|p\right|\right)} \]
    4. Applied rewrites10.2%

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

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left|p\right| + -1 \cdot \left(p \cdot \left(-2 \cdot \frac{r}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}} + 4 \cdot \left(\frac{{q}^{2} \cdot r}{{\left(\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}\right)}^{2}} \cdot \sqrt{\frac{1}{4 \cdot {q}^{2} + {r}^{2}}}\right)\right)\right)\right) - 4 \cdot \frac{{q}^{2}}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}}\right)} \]
    6. Applied rewrites44.8%

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

      \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + 2 \cdot \frac{p \cdot r}{r + \left|r\right|}\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]
    8. Step-by-step derivation
      1. Applied rewrites34.8%

        \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]

      if 1e110 < (pow.f64 q #s(literal 2 binary64))

      1. Initial program 23.1%

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

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

          \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
        2. lower-neg.f6434.8

          \[\leadsto \color{blue}{-q} \]
      5. Applied rewrites34.8%

        \[\leadsto \color{blue}{-q} \]
    9. Recombined 2 regimes into one program.
    10. Final simplification34.8%

      \[\leadsto \begin{array}{l} \mathbf{if}\;{q}^{2} \leq 10^{+110}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\\ \end{array} \]
    11. Add Preprocessing

    Alternative 2: 59.6% accurate, 0.9× speedup?

    \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;{q\_m}^{2} \leq 10^{+114}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{\mathsf{fma}\left(\frac{q\_m \cdot q\_m}{r}, 2, r\right) + \left|r\right|}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
    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 (<= (pow q_m 2.0) 1e+114)
       (*
        (pow 2.0 -1.0)
        (+
         (fma 2.0 (* p (/ r (+ (fabs r) r))) (fabs p))
         (* -4.0 (/ (* q_m q_m) (+ (fma (/ (* q_m q_m) r) 2.0 r) (fabs r))))))
       (- q_m)))
    q_m = fabs(q);
    assert(p < r && r < q_m);
    double code(double p, double r, double q_m) {
    	double tmp;
    	if (pow(q_m, 2.0) <= 1e+114) {
    		tmp = pow(2.0, -1.0) * (fma(2.0, (p * (r / (fabs(r) + r))), fabs(p)) + (-4.0 * ((q_m * q_m) / (fma(((q_m * q_m) / r), 2.0, r) + fabs(r)))));
    	} 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 ^ 2.0) <= 1e+114)
    		tmp = Float64((2.0 ^ -1.0) * Float64(fma(2.0, Float64(p * Float64(r / Float64(abs(r) + r))), abs(p)) + Float64(-4.0 * Float64(Float64(q_m * q_m) / Float64(fma(Float64(Float64(q_m * q_m) / r), 2.0, r) + abs(r))))));
    	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[N[Power[q$95$m, 2.0], $MachinePrecision], 1e+114], N[(N[Power[2.0, -1.0], $MachinePrecision] * N[(N[(2.0 * N[(p * N[(r / N[(N[Abs[r], $MachinePrecision] + r), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + N[(-4.0 * N[(N[(q$95$m * q$95$m), $MachinePrecision] / N[(N[(N[(N[(q$95$m * q$95$m), $MachinePrecision] / r), $MachinePrecision] * 2.0 + r), $MachinePrecision] + N[Abs[r], $MachinePrecision]), $MachinePrecision]), $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}^{2} \leq 10^{+114}:\\
    \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{\mathsf{fma}\left(\frac{q\_m \cdot q\_m}{r}, 2, r\right) + \left|r\right|}\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;-q\_m\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (pow.f64 q #s(literal 2 binary64)) < 1e114

      1. Initial program 24.1%

        \[\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}\right) \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

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

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

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

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

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

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

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(\left|r\right| \cdot \left|r\right| - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}} \cdot \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}, \frac{1}{\left|r\right| + \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}}, \left|p\right|\right)} \]
      4. Applied rewrites10.2%

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

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left|p\right| + -1 \cdot \left(p \cdot \left(-2 \cdot \frac{r}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}} + 4 \cdot \left(\frac{{q}^{2} \cdot r}{{\left(\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}\right)}^{2}} \cdot \sqrt{\frac{1}{4 \cdot {q}^{2} + {r}^{2}}}\right)\right)\right)\right) - 4 \cdot \frac{{q}^{2}}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}}\right)} \]
      6. Applied rewrites44.5%

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

        \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + 2 \cdot \frac{p \cdot r}{r + \left|r\right|}\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]
      8. Step-by-step derivation
        1. Applied rewrites34.6%

          \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]
        2. Taylor expanded in q around 0

          \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\left(r + 2 \cdot \frac{{q}^{2}}{r}\right) + \left|\color{blue}{r}\right|}\right) \]
        3. Step-by-step derivation
          1. Applied rewrites34.5%

            \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\mathsf{fma}\left(\frac{q \cdot q}{r}, 2, r\right) + \left|\color{blue}{r}\right|}\right) \]

          if 1e114 < (pow.f64 q #s(literal 2 binary64))

          1. Initial program 23.3%

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

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

              \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
            2. lower-neg.f6435.1

              \[\leadsto \color{blue}{-q} \]
          5. Applied rewrites35.1%

            \[\leadsto \color{blue}{-q} \]
        4. Recombined 2 regimes into one program.
        5. Final simplification34.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;{q}^{2} \leq 10^{+114}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\mathsf{fma}\left(\frac{q \cdot q}{r}, 2, r\right) + \left|r\right|}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\\ \end{array} \]
        6. Add Preprocessing

        Alternative 3: 59.3% accurate, 0.9× speedup?

        \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} t_0 := \left|r\right| + r\\ \mathbf{if}\;{q\_m}^{2} \leq 10^{+110}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{t\_0}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{t\_0}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
        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
         (let* ((t_0 (+ (fabs r) r)))
           (if (<= (pow q_m 2.0) 1e+110)
             (*
              (pow 2.0 -1.0)
              (+ (fma 2.0 (* p (/ r t_0)) (fabs p)) (* -4.0 (/ (* q_m q_m) t_0))))
             (- q_m))))
        q_m = fabs(q);
        assert(p < r && r < q_m);
        double code(double p, double r, double q_m) {
        	double t_0 = fabs(r) + r;
        	double tmp;
        	if (pow(q_m, 2.0) <= 1e+110) {
        		tmp = pow(2.0, -1.0) * (fma(2.0, (p * (r / t_0)), fabs(p)) + (-4.0 * ((q_m * q_m) / t_0)));
        	} 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)
        	t_0 = Float64(abs(r) + r)
        	tmp = 0.0
        	if ((q_m ^ 2.0) <= 1e+110)
        		tmp = Float64((2.0 ^ -1.0) * Float64(fma(2.0, Float64(p * Float64(r / t_0)), abs(p)) + Float64(-4.0 * Float64(Float64(q_m * q_m) / t_0))));
        	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_] := Block[{t$95$0 = N[(N[Abs[r], $MachinePrecision] + r), $MachinePrecision]}, If[LessEqual[N[Power[q$95$m, 2.0], $MachinePrecision], 1e+110], N[(N[Power[2.0, -1.0], $MachinePrecision] * N[(N[(2.0 * N[(p * N[(r / t$95$0), $MachinePrecision]), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + N[(-4.0 * N[(N[(q$95$m * q$95$m), $MachinePrecision] / t$95$0), $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}
        t_0 := \left|r\right| + r\\
        \mathbf{if}\;{q\_m}^{2} \leq 10^{+110}:\\
        \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{t\_0}, \left|p\right|\right) + -4 \cdot \frac{q\_m \cdot q\_m}{t\_0}\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;-q\_m\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (pow.f64 q #s(literal 2 binary64)) < 1e110

          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. Add Preprocessing
          3. Step-by-step derivation
            1. lift--.f64N/A

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

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

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

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

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

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

              \[\leadsto \frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(\left|r\right| \cdot \left|r\right| - \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}} \cdot \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}, \frac{1}{\left|r\right| + \sqrt{{\left(p - r\right)}^{2} + 4 \cdot {q}^{2}}}, \left|p\right|\right)} \]
          4. Applied rewrites10.2%

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

            \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left|p\right| + -1 \cdot \left(p \cdot \left(-2 \cdot \frac{r}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}} + 4 \cdot \left(\frac{{q}^{2} \cdot r}{{\left(\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}\right)}^{2}} \cdot \sqrt{\frac{1}{4 \cdot {q}^{2} + {r}^{2}}}\right)\right)\right)\right) - 4 \cdot \frac{{q}^{2}}{\left|r\right| + \sqrt{4 \cdot {q}^{2} + {r}^{2}}}\right)} \]
          6. Applied rewrites44.8%

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

            \[\leadsto \frac{1}{2} \cdot \left(\left(\left|p\right| + 2 \cdot \frac{p \cdot r}{r + \left|r\right|}\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]
          8. Step-by-step derivation
            1. Applied rewrites34.8%

              \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + \color{blue}{-4} \cdot \frac{q \cdot q}{\sqrt{\mathsf{fma}\left(q \cdot q, 4, r \cdot r\right)} + \left|r\right|}\right) \]
            2. Taylor expanded in q around 0

              \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{{q}^{2}}{\color{blue}{r + \left|r\right|}}\right) \]
            3. Step-by-step derivation
              1. Applied rewrites34.7%

                \[\leadsto \frac{1}{2} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\color{blue}{\left|r\right| + r}}\right) \]

              if 1e110 < (pow.f64 q #s(literal 2 binary64))

              1. Initial program 23.1%

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

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

                  \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
                2. lower-neg.f6434.8

                  \[\leadsto \color{blue}{-q} \]
              5. Applied rewrites34.8%

                \[\leadsto \color{blue}{-q} \]
            4. Recombined 2 regimes into one program.
            5. Final simplification34.7%

              \[\leadsto \begin{array}{l} \mathbf{if}\;{q}^{2} \leq 10^{+110}:\\ \;\;\;\;{2}^{-1} \cdot \left(\mathsf{fma}\left(2, p \cdot \frac{r}{\left|r\right| + r}, \left|p\right|\right) + -4 \cdot \frac{q \cdot q}{\left|r\right| + r}\right)\\ \mathbf{else}:\\ \;\;\;\;-q\\ \end{array} \]
            6. Add Preprocessing

            Alternative 4: 57.9% accurate, 1.1× speedup?

            \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;{q\_m}^{2} \leq 5 \cdot 10^{-164}:\\ \;\;\;\;0.5 \cdot \left(\left(\left(\left|r\right| - r\right) + \left|p\right|\right) + p\right)\\ \mathbf{elif}\;{q\_m}^{2} \leq 5 \cdot 10^{-18}:\\ \;\;\;\;\frac{\left(-q\_m\right) \cdot q\_m}{r}\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
            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 (<= (pow q_m 2.0) 5e-164)
               (* 0.5 (+ (+ (- (fabs r) r) (fabs p)) p))
               (if (<= (pow q_m 2.0) 5e-18) (/ (* (- q_m) q_m) r) (- q_m))))
            q_m = fabs(q);
            assert(p < r && r < q_m);
            double code(double p, double r, double q_m) {
            	double tmp;
            	if (pow(q_m, 2.0) <= 5e-164) {
            		tmp = 0.5 * (((fabs(r) - r) + fabs(p)) + p);
            	} else if (pow(q_m, 2.0) <= 5e-18) {
            		tmp = (-q_m * q_m) / r;
            	} else {
            		tmp = -q_m;
            	}
            	return tmp;
            }
            
            q_m = abs(q)
            NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
            real(8) function code(p, r, q_m)
                real(8), intent (in) :: p
                real(8), intent (in) :: r
                real(8), intent (in) :: q_m
                real(8) :: tmp
                if ((q_m ** 2.0d0) <= 5d-164) then
                    tmp = 0.5d0 * (((abs(r) - r) + abs(p)) + p)
                else if ((q_m ** 2.0d0) <= 5d-18) then
                    tmp = (-q_m * q_m) / r
                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 (Math.pow(q_m, 2.0) <= 5e-164) {
            		tmp = 0.5 * (((Math.abs(r) - r) + Math.abs(p)) + p);
            	} else if (Math.pow(q_m, 2.0) <= 5e-18) {
            		tmp = (-q_m * q_m) / r;
            	} 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 math.pow(q_m, 2.0) <= 5e-164:
            		tmp = 0.5 * (((math.fabs(r) - r) + math.fabs(p)) + p)
            	elif math.pow(q_m, 2.0) <= 5e-18:
            		tmp = (-q_m * q_m) / r
            	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 ^ 2.0) <= 5e-164)
            		tmp = Float64(0.5 * Float64(Float64(Float64(abs(r) - r) + abs(p)) + p));
            	elseif ((q_m ^ 2.0) <= 5e-18)
            		tmp = Float64(Float64(Float64(-q_m) * q_m) / r);
            	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 ^ 2.0) <= 5e-164)
            		tmp = 0.5 * (((abs(r) - r) + abs(p)) + p);
            	elseif ((q_m ^ 2.0) <= 5e-18)
            		tmp = (-q_m * q_m) / r;
            	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[Power[q$95$m, 2.0], $MachinePrecision], 5e-164], N[(0.5 * N[(N[(N[(N[Abs[r], $MachinePrecision] - r), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + p), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[Power[q$95$m, 2.0], $MachinePrecision], 5e-18], N[(N[((-q$95$m) * q$95$m), $MachinePrecision] / r), $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}^{2} \leq 5 \cdot 10^{-164}:\\
            \;\;\;\;0.5 \cdot \left(\left(\left(\left|r\right| - r\right) + \left|p\right|\right) + p\right)\\
            
            \mathbf{elif}\;{q\_m}^{2} \leq 5 \cdot 10^{-18}:\\
            \;\;\;\;\frac{\left(-q\_m\right) \cdot q\_m}{r}\\
            
            \mathbf{else}:\\
            \;\;\;\;-q\_m\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if (pow.f64 q #s(literal 2 binary64)) < 4.99999999999999962e-164

              1. Initial program 27.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \left(-p\right) \cdot \mathsf{fma}\left(\frac{\left(\color{blue}{\left|r\right|} + \left|p\right|\right) - r}{p}, \frac{-1}{2}, \frac{-1}{2}\right) \]
                14. lower-fabs.f6416.4

                  \[\leadsto \left(-p\right) \cdot \mathsf{fma}\left(\frac{\left(\left|r\right| + \color{blue}{\left|p\right|}\right) - r}{p}, -0.5, -0.5\right) \]
              5. Applied rewrites16.4%

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

                \[\leadsto \frac{1}{2} \cdot p + \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right)} \]
              7. Step-by-step derivation
                1. Applied rewrites39.8%

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

                if 4.99999999999999962e-164 < (pow.f64 q #s(literal 2 binary64)) < 5.00000000000000036e-18

                1. Initial program 7.2%

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

                  \[\leadsto \color{blue}{r \cdot \left(\left(-1 \cdot \frac{p \cdot {q}^{2}}{{r}^{3}} + \left(-1 \cdot \frac{{q}^{2}}{{r}^{2}} + \frac{1}{2} \cdot \frac{\left(\left|p\right| + \left|r\right|\right) - -1 \cdot p}{r}\right)\right) - \frac{1}{2}\right)} \]
                4. Applied rewrites14.9%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(-1, \left(\frac{p}{r} + 1\right) \cdot \left(\frac{q}{r} \cdot \frac{q}{r}\right), \mathsf{fma}\left(\frac{\left(\left|r\right| + p\right) + \left|p\right|}{r}, 0.5, -0.5\right)\right) \cdot r} \]
                5. Taylor expanded in r around 0

                  \[\leadsto \frac{-1 \cdot \left(p \cdot {q}^{2}\right) + -1 \cdot \left({q}^{2} \cdot r\right)}{\color{blue}{{r}^{2}}} \]
                6. Step-by-step derivation
                  1. Applied rewrites15.9%

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

                    \[\leadsto -1 \cdot \frac{{q}^{2}}{\color{blue}{r}} \]
                  3. Step-by-step derivation
                    1. Applied rewrites26.9%

                      \[\leadsto -\frac{q \cdot q}{r} \]

                    if 5.00000000000000036e-18 < (pow.f64 q #s(literal 2 binary64))

                    1. Initial program 25.3%

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

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

                        \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
                      2. lower-neg.f6429.7

                        \[\leadsto \color{blue}{-q} \]
                    5. Applied rewrites29.7%

                      \[\leadsto \color{blue}{-q} \]
                  4. Recombined 3 regimes into one program.
                  5. Final simplification33.1%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;{q}^{2} \leq 5 \cdot 10^{-164}:\\ \;\;\;\;0.5 \cdot \left(\left(\left(\left|r\right| - r\right) + \left|p\right|\right) + p\right)\\ \mathbf{elif}\;{q}^{2} \leq 5 \cdot 10^{-18}:\\ \;\;\;\;\frac{\left(-q\right) \cdot q}{r}\\ \mathbf{else}:\\ \;\;\;\;-q\\ \end{array} \]
                  6. Add Preprocessing

                  Alternative 5: 58.4% accurate, 2.0× speedup?

                  \[\begin{array}{l} q_m = \left|q\right| \\ [p, r, q_m] = \mathsf{sort}([p, r, q_m])\\ \\ \begin{array}{l} \mathbf{if}\;{q\_m}^{2} \leq 4 \cdot 10^{-46}:\\ \;\;\;\;0.5 \cdot \left(\left(\left(\left|r\right| - r\right) + \left|p\right|\right) + p\right)\\ \mathbf{else}:\\ \;\;\;\;-q\_m\\ \end{array} \end{array} \]
                  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 (<= (pow q_m 2.0) 4e-46)
                     (* 0.5 (+ (+ (- (fabs r) r) (fabs p)) 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 (pow(q_m, 2.0) <= 4e-46) {
                  		tmp = 0.5 * (((fabs(r) - r) + fabs(p)) + p);
                  	} else {
                  		tmp = -q_m;
                  	}
                  	return tmp;
                  }
                  
                  q_m = abs(q)
                  NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
                  real(8) function code(p, r, q_m)
                      real(8), intent (in) :: p
                      real(8), intent (in) :: r
                      real(8), intent (in) :: q_m
                      real(8) :: tmp
                      if ((q_m ** 2.0d0) <= 4d-46) then
                          tmp = 0.5d0 * (((abs(r) - r) + abs(p)) + 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 (Math.pow(q_m, 2.0) <= 4e-46) {
                  		tmp = 0.5 * (((Math.abs(r) - r) + Math.abs(p)) + 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 math.pow(q_m, 2.0) <= 4e-46:
                  		tmp = 0.5 * (((math.fabs(r) - r) + math.fabs(p)) + 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 ^ 2.0) <= 4e-46)
                  		tmp = Float64(0.5 * Float64(Float64(Float64(abs(r) - r) + abs(p)) + 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 ^ 2.0) <= 4e-46)
                  		tmp = 0.5 * (((abs(r) - r) + abs(p)) + 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[N[Power[q$95$m, 2.0], $MachinePrecision], 4e-46], N[(0.5 * N[(N[(N[(N[Abs[r], $MachinePrecision] - r), $MachinePrecision] + N[Abs[p], $MachinePrecision]), $MachinePrecision] + p), $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}^{2} \leq 4 \cdot 10^{-46}:\\
                  \;\;\;\;0.5 \cdot \left(\left(\left(\left|r\right| - r\right) + \left|p\right|\right) + p\right)\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;-q\_m\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if (pow.f64 q #s(literal 2 binary64)) < 4.00000000000000009e-46

                    1. Initial program 23.0%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                        \[\leadsto \left(-p\right) \cdot \mathsf{fma}\left(\frac{\left(\color{blue}{\left|r\right|} + \left|p\right|\right) - r}{p}, \frac{-1}{2}, \frac{-1}{2}\right) \]
                      14. lower-fabs.f6414.2

                        \[\leadsto \left(-p\right) \cdot \mathsf{fma}\left(\frac{\left(\left|r\right| + \color{blue}{\left|p\right|}\right) - r}{p}, -0.5, -0.5\right) \]
                    5. Applied rewrites14.2%

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

                      \[\leadsto \frac{1}{2} \cdot p + \color{blue}{\frac{1}{2} \cdot \left(\left(\left|p\right| + \left|r\right|\right) - r\right)} \]
                    7. Step-by-step derivation
                      1. Applied rewrites34.2%

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

                      if 4.00000000000000009e-46 < (pow.f64 q #s(literal 2 binary64))

                      1. Initial program 24.6%

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

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

                          \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
                        2. lower-neg.f6428.9

                          \[\leadsto \color{blue}{-q} \]
                      5. Applied rewrites28.9%

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

                    Alternative 6: 36.1% 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 = abs(q)
                    NOTE: p, r, and q_m should be sorted in increasing order before calling this function.
                    real(8) function code(p, r, q_m)
                        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 23.8%

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

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

                        \[\leadsto \color{blue}{\mathsf{neg}\left(q\right)} \]
                      2. lower-neg.f6417.6

                        \[\leadsto \color{blue}{-q} \]
                    5. Applied rewrites17.6%

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

                    Reproduce

                    ?
                    herbie shell --seed 2024314 
                    (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)))))))