Maksimov and Kolovsky, Equation (3)

Percentage Accurate: 72.7% → 99.2%
Time: 10.5s
Alternatives: 7
Speedup: 1.3×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot t\_0}\right)}^{2}} \end{array} \end{array} \]
(FPCore (J K U)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0))))
   (* (* (* -2.0 J) t_0) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) t_0)) 2.0))))))
double code(double J, double K, double U) {
	double t_0 = cos((K / 2.0));
	return ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U / ((2.0 * J) * t_0)), 2.0)));
}
real(8) function code(j, k, u)
    real(8), intent (in) :: j
    real(8), intent (in) :: k
    real(8), intent (in) :: u
    real(8) :: t_0
    t_0 = cos((k / 2.0d0))
    code = (((-2.0d0) * j) * t_0) * sqrt((1.0d0 + ((u / ((2.0d0 * j) * t_0)) ** 2.0d0)))
end function
public static double code(double J, double K, double U) {
	double t_0 = Math.cos((K / 2.0));
	return ((-2.0 * J) * t_0) * Math.sqrt((1.0 + Math.pow((U / ((2.0 * J) * t_0)), 2.0)));
}
def code(J, K, U):
	t_0 = math.cos((K / 2.0))
	return ((-2.0 * J) * t_0) * math.sqrt((1.0 + math.pow((U / ((2.0 * J) * t_0)), 2.0)))
function code(J, K, U)
	t_0 = cos(Float64(K / 2.0))
	return Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U / Float64(Float64(2.0 * J) * t_0)) ^ 2.0))))
end
function tmp = code(J, K, U)
	t_0 = cos((K / 2.0));
	tmp = ((-2.0 * J) * t_0) * sqrt((1.0 + ((U / ((2.0 * J) * t_0)) ^ 2.0)));
end
code[J_, K_, U_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U / N[(N[(2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
\left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot t\_0}\right)}^{2}}
\end{array}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 7 alternatives:

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

Initial Program: 72.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot t\_0}\right)}^{2}} \end{array} \end{array} \]
(FPCore (J K U)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0))))
   (* (* (* -2.0 J) t_0) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) t_0)) 2.0))))))
double code(double J, double K, double U) {
	double t_0 = cos((K / 2.0));
	return ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U / ((2.0 * J) * t_0)), 2.0)));
}
real(8) function code(j, k, u)
    real(8), intent (in) :: j
    real(8), intent (in) :: k
    real(8), intent (in) :: u
    real(8) :: t_0
    t_0 = cos((k / 2.0d0))
    code = (((-2.0d0) * j) * t_0) * sqrt((1.0d0 + ((u / ((2.0d0 * j) * t_0)) ** 2.0d0)))
end function
public static double code(double J, double K, double U) {
	double t_0 = Math.cos((K / 2.0));
	return ((-2.0 * J) * t_0) * Math.sqrt((1.0 + Math.pow((U / ((2.0 * J) * t_0)), 2.0)));
}
def code(J, K, U):
	t_0 = math.cos((K / 2.0))
	return ((-2.0 * J) * t_0) * math.sqrt((1.0 + math.pow((U / ((2.0 * J) * t_0)), 2.0)))
function code(J, K, U)
	t_0 = cos(Float64(K / 2.0))
	return Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U / Float64(Float64(2.0 * J) * t_0)) ^ 2.0))))
end
function tmp = code(J, K, U)
	t_0 = cos((K / 2.0));
	tmp = ((-2.0 * J) * t_0) * sqrt((1.0 + ((U / ((2.0 * J) * t_0)) ^ 2.0)));
end
code[J_, K_, U_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U / N[(N[(2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
\left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot t\_0}\right)}^{2}}
\end{array}
\end{array}

Alternative 1: 99.2% accurate, 0.3× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\_m\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J\_m \cdot 2\right)}\right)}^{2}}\\ J\_s \cdot \begin{array}{l} \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;0 - U\_m\\ \mathbf{elif}\;t\_1 \leq 10^{+292}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;U\_m\\ \end{array} \end{array} \end{array} \]
U_m = (fabs.f64 U)
J\_m = (fabs.f64 J)
J\_s = (copysign.f64 #s(literal 1 binary64) J)
(FPCore (J_s J_m K U_m)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0)))
        (t_1
         (*
          (* (* -2.0 J_m) t_0)
          (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J_m 2.0))) 2.0))))))
   (*
    J_s
    (if (<= t_1 (- INFINITY)) (- 0.0 U_m) (if (<= t_1 1e+292) t_1 U_m)))))
U_m = fabs(U);
J\_m = fabs(J);
J\_s = copysign(1.0, J);
double code(double J_s, double J_m, double K, double U_m) {
	double t_0 = cos((K / 2.0));
	double t_1 = ((-2.0 * J_m) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J_m * 2.0))), 2.0)));
	double tmp;
	if (t_1 <= -((double) INFINITY)) {
		tmp = 0.0 - U_m;
	} else if (t_1 <= 1e+292) {
		tmp = t_1;
	} else {
		tmp = U_m;
	}
	return J_s * tmp;
}
U_m = Math.abs(U);
J\_m = Math.abs(J);
J\_s = Math.copySign(1.0, J);
public static double code(double J_s, double J_m, double K, double U_m) {
	double t_0 = Math.cos((K / 2.0));
	double t_1 = ((-2.0 * J_m) * t_0) * Math.sqrt((1.0 + Math.pow((U_m / (t_0 * (J_m * 2.0))), 2.0)));
	double tmp;
	if (t_1 <= -Double.POSITIVE_INFINITY) {
		tmp = 0.0 - U_m;
	} else if (t_1 <= 1e+292) {
		tmp = t_1;
	} else {
		tmp = U_m;
	}
	return J_s * tmp;
}
U_m = math.fabs(U)
J\_m = math.fabs(J)
J\_s = math.copysign(1.0, J)
def code(J_s, J_m, K, U_m):
	t_0 = math.cos((K / 2.0))
	t_1 = ((-2.0 * J_m) * t_0) * math.sqrt((1.0 + math.pow((U_m / (t_0 * (J_m * 2.0))), 2.0)))
	tmp = 0
	if t_1 <= -math.inf:
		tmp = 0.0 - U_m
	elif t_1 <= 1e+292:
		tmp = t_1
	else:
		tmp = U_m
	return J_s * tmp
U_m = abs(U)
J\_m = abs(J)
J\_s = copysign(1.0, J)
function code(J_s, J_m, K, U_m)
	t_0 = cos(Float64(K / 2.0))
	t_1 = Float64(Float64(Float64(-2.0 * J_m) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J_m * 2.0))) ^ 2.0))))
	tmp = 0.0
	if (t_1 <= Float64(-Inf))
		tmp = Float64(0.0 - U_m);
	elseif (t_1 <= 1e+292)
		tmp = t_1;
	else
		tmp = U_m;
	end
	return Float64(J_s * tmp)
end
U_m = abs(U);
J\_m = abs(J);
J\_s = sign(J) * abs(1.0);
function tmp_2 = code(J_s, J_m, K, U_m)
	t_0 = cos((K / 2.0));
	t_1 = ((-2.0 * J_m) * t_0) * sqrt((1.0 + ((U_m / (t_0 * (J_m * 2.0))) ^ 2.0)));
	tmp = 0.0;
	if (t_1 <= -Inf)
		tmp = 0.0 - U_m;
	elseif (t_1 <= 1e+292)
		tmp = t_1;
	else
		tmp = U_m;
	end
	tmp_2 = J_s * tmp;
end
U_m = N[Abs[U], $MachinePrecision]
J\_m = N[Abs[J], $MachinePrecision]
J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[J$95$s_, J$95$m_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(N[(-2.0 * J$95$m), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J$95$m * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, N[(J$95$s * If[LessEqual[t$95$1, (-Infinity)], N[(0.0 - U$95$m), $MachinePrecision], If[LessEqual[t$95$1, 1e+292], t$95$1, U$95$m]]), $MachinePrecision]]]
\begin{array}{l}
U_m = \left|U\right|
\\
J\_m = \left|J\right|
\\
J\_s = \mathsf{copysign}\left(1, J\right)

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
t_1 := \left(\left(-2 \cdot J\_m\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J\_m \cdot 2\right)}\right)}^{2}}\\
J\_s \cdot \begin{array}{l}
\mathbf{if}\;t\_1 \leq -\infty:\\
\;\;\;\;0 - U\_m\\

\mathbf{elif}\;t\_1 \leq 10^{+292}:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;U\_m\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 (*.f64 (*.f64 #s(literal -2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64)))) (sqrt.f64 (+.f64 #s(literal 1 binary64) (pow.f64 (/.f64 U (*.f64 (*.f64 #s(literal 2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64))))) #s(literal 2 binary64))))) < -inf.0

    1. Initial program 5.6%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Add Preprocessing
    3. Taylor expanded in J around 0

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

        \[\leadsto \mathsf{neg}\left(U\right) \]
      2. neg-sub0N/A

        \[\leadsto 0 - \color{blue}{U} \]
      3. --lowering--.f6443.6%

        \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
    5. Simplified43.6%

      \[\leadsto \color{blue}{0 - U} \]
    6. Step-by-step derivation
      1. sub0-negN/A

        \[\leadsto \mathsf{neg}\left(U\right) \]
      2. neg-lowering-neg.f6443.6%

        \[\leadsto \mathsf{neg.f64}\left(U\right) \]
    7. Applied egg-rr43.6%

      \[\leadsto \color{blue}{-U} \]

    if -inf.0 < (*.f64 (*.f64 (*.f64 #s(literal -2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64)))) (sqrt.f64 (+.f64 #s(literal 1 binary64) (pow.f64 (/.f64 U (*.f64 (*.f64 #s(literal 2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64))))) #s(literal 2 binary64))))) < 1e292

    1. Initial program 99.8%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Add Preprocessing

    if 1e292 < (*.f64 (*.f64 (*.f64 #s(literal -2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64)))) (sqrt.f64 (+.f64 #s(literal 1 binary64) (pow.f64 (/.f64 U (*.f64 (*.f64 #s(literal 2 binary64) J) (cos.f64 (/.f64 K #s(literal 2 binary64))))) #s(literal 2 binary64)))))

    1. Initial program 14.6%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Add Preprocessing
    3. Taylor expanded in U around -inf

      \[\leadsto \color{blue}{U} \]
    4. Step-by-step derivation
      1. Simplified37.6%

        \[\leadsto \color{blue}{U} \]
    5. Recombined 3 regimes into one program.
    6. Final simplification81.2%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;0 - U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 10^{+292}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;U\\ \end{array} \]
    7. Add Preprocessing

    Alternative 2: 69.6% accurate, 0.6× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ J\_s \cdot \begin{array}{l} \mathbf{if}\;t\_0 \leq -0.05:\\ \;\;\;\;U\_m\\ \mathbf{elif}\;t\_0 \leq 0.2:\\ \;\;\;\;\frac{1}{\frac{1}{\left(-2 \cdot J\_m\right) \cdot t\_0}}\\ \mathbf{elif}\;t\_0 \leq 0.925:\\ \;\;\;\;0 - U\_m\\ \mathbf{elif}\;t\_0 \leq 0.99996:\\ \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{hypot}\left(1, \frac{\frac{U\_m}{J\_m \cdot 2}}{t\_0}\right) \cdot \left(-2 \cdot J\_m + 0.25 \cdot \left(J\_m \cdot \left(K \cdot K\right)\right)\right)\\ \end{array} \end{array} \end{array} \]
    U_m = (fabs.f64 U)
    J\_m = (fabs.f64 J)
    J\_s = (copysign.f64 #s(literal 1 binary64) J)
    (FPCore (J_s J_m K U_m)
     :precision binary64
     (let* ((t_0 (cos (/ K 2.0))))
       (*
        J_s
        (if (<= t_0 -0.05)
          U_m
          (if (<= t_0 0.2)
            (/ 1.0 (/ 1.0 (* (* -2.0 J_m) t_0)))
            (if (<= t_0 0.925)
              (- 0.0 U_m)
              (if (<= t_0 0.99996)
                (* (* -2.0 J_m) (cos (* K 0.5)))
                (*
                 (hypot 1.0 (/ (/ U_m (* J_m 2.0)) t_0))
                 (+ (* -2.0 J_m) (* 0.25 (* J_m (* K K))))))))))))
    U_m = fabs(U);
    J\_m = fabs(J);
    J\_s = copysign(1.0, J);
    double code(double J_s, double J_m, double K, double U_m) {
    	double t_0 = cos((K / 2.0));
    	double tmp;
    	if (t_0 <= -0.05) {
    		tmp = U_m;
    	} else if (t_0 <= 0.2) {
    		tmp = 1.0 / (1.0 / ((-2.0 * J_m) * t_0));
    	} else if (t_0 <= 0.925) {
    		tmp = 0.0 - U_m;
    	} else if (t_0 <= 0.99996) {
    		tmp = (-2.0 * J_m) * cos((K * 0.5));
    	} else {
    		tmp = hypot(1.0, ((U_m / (J_m * 2.0)) / t_0)) * ((-2.0 * J_m) + (0.25 * (J_m * (K * K))));
    	}
    	return J_s * tmp;
    }
    
    U_m = Math.abs(U);
    J\_m = Math.abs(J);
    J\_s = Math.copySign(1.0, J);
    public static double code(double J_s, double J_m, double K, double U_m) {
    	double t_0 = Math.cos((K / 2.0));
    	double tmp;
    	if (t_0 <= -0.05) {
    		tmp = U_m;
    	} else if (t_0 <= 0.2) {
    		tmp = 1.0 / (1.0 / ((-2.0 * J_m) * t_0));
    	} else if (t_0 <= 0.925) {
    		tmp = 0.0 - U_m;
    	} else if (t_0 <= 0.99996) {
    		tmp = (-2.0 * J_m) * Math.cos((K * 0.5));
    	} else {
    		tmp = Math.hypot(1.0, ((U_m / (J_m * 2.0)) / t_0)) * ((-2.0 * J_m) + (0.25 * (J_m * (K * K))));
    	}
    	return J_s * tmp;
    }
    
    U_m = math.fabs(U)
    J\_m = math.fabs(J)
    J\_s = math.copysign(1.0, J)
    def code(J_s, J_m, K, U_m):
    	t_0 = math.cos((K / 2.0))
    	tmp = 0
    	if t_0 <= -0.05:
    		tmp = U_m
    	elif t_0 <= 0.2:
    		tmp = 1.0 / (1.0 / ((-2.0 * J_m) * t_0))
    	elif t_0 <= 0.925:
    		tmp = 0.0 - U_m
    	elif t_0 <= 0.99996:
    		tmp = (-2.0 * J_m) * math.cos((K * 0.5))
    	else:
    		tmp = math.hypot(1.0, ((U_m / (J_m * 2.0)) / t_0)) * ((-2.0 * J_m) + (0.25 * (J_m * (K * K))))
    	return J_s * tmp
    
    U_m = abs(U)
    J\_m = abs(J)
    J\_s = copysign(1.0, J)
    function code(J_s, J_m, K, U_m)
    	t_0 = cos(Float64(K / 2.0))
    	tmp = 0.0
    	if (t_0 <= -0.05)
    		tmp = U_m;
    	elseif (t_0 <= 0.2)
    		tmp = Float64(1.0 / Float64(1.0 / Float64(Float64(-2.0 * J_m) * t_0)));
    	elseif (t_0 <= 0.925)
    		tmp = Float64(0.0 - U_m);
    	elseif (t_0 <= 0.99996)
    		tmp = Float64(Float64(-2.0 * J_m) * cos(Float64(K * 0.5)));
    	else
    		tmp = Float64(hypot(1.0, Float64(Float64(U_m / Float64(J_m * 2.0)) / t_0)) * Float64(Float64(-2.0 * J_m) + Float64(0.25 * Float64(J_m * Float64(K * K)))));
    	end
    	return Float64(J_s * tmp)
    end
    
    U_m = abs(U);
    J\_m = abs(J);
    J\_s = sign(J) * abs(1.0);
    function tmp_2 = code(J_s, J_m, K, U_m)
    	t_0 = cos((K / 2.0));
    	tmp = 0.0;
    	if (t_0 <= -0.05)
    		tmp = U_m;
    	elseif (t_0 <= 0.2)
    		tmp = 1.0 / (1.0 / ((-2.0 * J_m) * t_0));
    	elseif (t_0 <= 0.925)
    		tmp = 0.0 - U_m;
    	elseif (t_0 <= 0.99996)
    		tmp = (-2.0 * J_m) * cos((K * 0.5));
    	else
    		tmp = hypot(1.0, ((U_m / (J_m * 2.0)) / t_0)) * ((-2.0 * J_m) + (0.25 * (J_m * (K * K))));
    	end
    	tmp_2 = J_s * tmp;
    end
    
    U_m = N[Abs[U], $MachinePrecision]
    J\_m = N[Abs[J], $MachinePrecision]
    J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
    code[J$95$s_, J$95$m_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(J$95$s * If[LessEqual[t$95$0, -0.05], U$95$m, If[LessEqual[t$95$0, 0.2], N[(1.0 / N[(1.0 / N[(N[(-2.0 * J$95$m), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.925], N[(0.0 - U$95$m), $MachinePrecision], If[LessEqual[t$95$0, 0.99996], N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / N[(J$95$m * 2.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] ^ 2], $MachinePrecision] * N[(N[(-2.0 * J$95$m), $MachinePrecision] + N[(0.25 * N[(J$95$m * N[(K * K), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]), $MachinePrecision]]
    
    \begin{array}{l}
    U_m = \left|U\right|
    \\
    J\_m = \left|J\right|
    \\
    J\_s = \mathsf{copysign}\left(1, J\right)
    
    \\
    \begin{array}{l}
    t_0 := \cos \left(\frac{K}{2}\right)\\
    J\_s \cdot \begin{array}{l}
    \mathbf{if}\;t\_0 \leq -0.05:\\
    \;\;\;\;U\_m\\
    
    \mathbf{elif}\;t\_0 \leq 0.2:\\
    \;\;\;\;\frac{1}{\frac{1}{\left(-2 \cdot J\_m\right) \cdot t\_0}}\\
    
    \mathbf{elif}\;t\_0 \leq 0.925:\\
    \;\;\;\;0 - U\_m\\
    
    \mathbf{elif}\;t\_0 \leq 0.99996:\\
    \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{hypot}\left(1, \frac{\frac{U\_m}{J\_m \cdot 2}}{t\_0}\right) \cdot \left(-2 \cdot J\_m + 0.25 \cdot \left(J\_m \cdot \left(K \cdot K\right)\right)\right)\\
    
    
    \end{array}
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 5 regimes
    2. if (cos.f64 (/.f64 K #s(literal 2 binary64))) < -0.050000000000000003

      1. Initial program 64.6%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Taylor expanded in U around -inf

        \[\leadsto \color{blue}{U} \]
      4. Step-by-step derivation
        1. Simplified34.8%

          \[\leadsto \color{blue}{U} \]

        if -0.050000000000000003 < (cos.f64 (/.f64 K #s(literal 2 binary64))) < 0.20000000000000001

        1. Initial program 99.7%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around inf

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

            \[\leadsto \left(-2 \cdot J\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)} \]
          2. *-commutativeN/A

            \[\leadsto \cos \left(\frac{1}{2} \cdot K\right) \cdot \color{blue}{\left(-2 \cdot J\right)} \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\left(-2 \cdot J\right)}\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\left(\frac{1}{2} \cdot K\right)\right), \left(\color{blue}{-2} \cdot J\right)\right) \]
          5. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \left(-2 \cdot J\right)\right) \]
          6. *-lowering-*.f6499.7%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
        5. Simplified99.7%

          \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]
        6. Step-by-step derivation
          1. *-commutativeN/A

            \[\leadsto \left(-2 \cdot J\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)} \]
          2. *-commutativeN/A

            \[\leadsto \left(-2 \cdot J\right) \cdot \cos \left(K \cdot \frac{1}{2}\right) \]
          3. metadata-evalN/A

            \[\leadsto \left(-2 \cdot J\right) \cdot \cos \left(K \cdot \frac{1}{2}\right) \]
          4. div-invN/A

            \[\leadsto \left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right) \]
          5. remove-double-divN/A

            \[\leadsto \left(-2 \cdot J\right) \cdot \frac{1}{\color{blue}{\frac{1}{\cos \left(\frac{K}{2}\right)}}} \]
          6. un-div-invN/A

            \[\leadsto \frac{-2 \cdot J}{\color{blue}{\frac{1}{\cos \left(\frac{K}{2}\right)}}} \]
          7. clear-numN/A

            \[\leadsto \frac{1}{\color{blue}{\frac{\frac{1}{\cos \left(\frac{K}{2}\right)}}{-2 \cdot J}}} \]
          8. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(\frac{\frac{1}{\cos \left(\frac{K}{2}\right)}}{-2 \cdot J}\right)}\right) \]
          9. clear-numN/A

            \[\leadsto \mathsf{/.f64}\left(1, \left(\frac{1}{\color{blue}{\frac{-2 \cdot J}{\frac{1}{\cos \left(\frac{K}{2}\right)}}}}\right)\right) \]
          10. un-div-invN/A

            \[\leadsto \mathsf{/.f64}\left(1, \left(\frac{1}{\left(-2 \cdot J\right) \cdot \color{blue}{\frac{1}{\frac{1}{\cos \left(\frac{K}{2}\right)}}}}\right)\right) \]
          11. remove-double-divN/A

            \[\leadsto \mathsf{/.f64}\left(1, \left(\frac{1}{\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)\right) \]
          12. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \color{blue}{\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right)}\right)\right) \]
          13. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\left(-2 \cdot J\right), \color{blue}{\cos \left(\frac{K}{2}\right)}\right)\right)\right) \]
          14. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \color{blue}{\left(\frac{K}{2}\right)}\right)\right)\right) \]
          15. div-invN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \left(K \cdot \frac{1}{2}\right)\right)\right)\right) \]
          16. metadata-evalN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \left(K \cdot \frac{1}{2}\right)\right)\right)\right) \]
          17. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \left(\frac{1}{2} \cdot K\right)\right)\right)\right) \]
          18. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(\frac{1}{2} \cdot K\right)\right)\right)\right)\right) \]
          19. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(K \cdot \frac{1}{2}\right)\right)\right)\right)\right) \]
          20. metadata-evalN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(K \cdot \frac{1}{2}\right)\right)\right)\right)\right) \]
          21. div-invN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(\frac{K}{2}\right)\right)\right)\right)\right) \]
          22. /-lowering-/.f64100.0%

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{/.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
        7. Applied egg-rr100.0%

          \[\leadsto \color{blue}{\frac{1}{\frac{1}{\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]

        if 0.20000000000000001 < (cos.f64 (/.f64 K #s(literal 2 binary64))) < 0.92500000000000004

        1. Initial program 69.7%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around 0

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

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-sub0N/A

            \[\leadsto 0 - \color{blue}{U} \]
          3. --lowering--.f6444.0%

            \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
        5. Simplified44.0%

          \[\leadsto \color{blue}{0 - U} \]
        6. Step-by-step derivation
          1. sub0-negN/A

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-lowering-neg.f6444.0%

            \[\leadsto \mathsf{neg.f64}\left(U\right) \]
        7. Applied egg-rr44.0%

          \[\leadsto \color{blue}{-U} \]

        if 0.92500000000000004 < (cos.f64 (/.f64 K #s(literal 2 binary64))) < 0.99995999999999996

        1. Initial program 74.9%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around inf

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

            \[\leadsto \left(-2 \cdot J\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)} \]
          2. *-commutativeN/A

            \[\leadsto \cos \left(\frac{1}{2} \cdot K\right) \cdot \color{blue}{\left(-2 \cdot J\right)} \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\left(-2 \cdot J\right)}\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\left(\frac{1}{2} \cdot K\right)\right), \left(\color{blue}{-2} \cdot J\right)\right) \]
          5. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \left(-2 \cdot J\right)\right) \]
          6. *-lowering-*.f6466.7%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
        5. Simplified66.7%

          \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]

        if 0.99995999999999996 < (cos.f64 (/.f64 K #s(literal 2 binary64)))

        1. Initial program 73.6%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Step-by-step derivation
          1. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right), \color{blue}{\left(\sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\right)}\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\left(-2 \cdot J\right), \cos \left(\frac{K}{2}\right)\right), \left(\sqrt{\color{blue}{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}}\right)\right) \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \left(\frac{K}{2}\right)\right), \left(\sqrt{\color{blue}{1} + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\right)\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(\frac{K}{2}\right)\right)\right), \left(\sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}}\right)\right) \]
          5. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\sqrt{1 + {\color{blue}{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}}^{2}}\right)\right) \]
          6. unpow2N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}\right)\right) \]
          7. hypot-1-defN/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}\right)\right)\right) \]
          8. hypot-lowering-hypot.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \color{blue}{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}\right)\right) \]
          9. associate-/r*N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \left(\frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(\frac{K}{2}\right)}}\right)\right)\right) \]
          10. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\left(\frac{U}{2 \cdot J}\right), \color{blue}{\cos \left(\frac{K}{2}\right)}\right)\right)\right) \]
          11. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \left(2 \cdot J\right)\right), \cos \color{blue}{\left(\frac{K}{2}\right)}\right)\right)\right) \]
          12. *-commutativeN/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \left(J \cdot 2\right)\right), \cos \left(\frac{K}{\color{blue}{2}}\right)\right)\right)\right) \]
          13. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \cos \left(\frac{K}{\color{blue}{2}}\right)\right)\right)\right) \]
          14. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\left(\frac{K}{2}\right)\right)\right)\right)\right) \]
          15. /-lowering-/.f6485.9%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
        3. Simplified85.9%

          \[\leadsto \color{blue}{\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
        4. Add Preprocessing
        5. Taylor expanded in K around 0

          \[\leadsto \mathsf{*.f64}\left(\color{blue}{\left(-2 \cdot J + \frac{1}{4} \cdot \left(J \cdot {K}^{2}\right)\right)}, \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
        6. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\left(-2 \cdot J\right), \left(\frac{1}{4} \cdot \left(J \cdot {K}^{2}\right)\right)\right), \mathsf{hypot.f64}\left(\color{blue}{1}, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\mathsf{*.f64}\left(-2, J\right), \left(\frac{1}{4} \cdot \left(J \cdot {K}^{2}\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{*.f64}\left(\frac{1}{4}, \left(J \cdot {K}^{2}\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
          4. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{*.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(J, \left({K}^{2}\right)\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
          5. unpow2N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{*.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(J, \left(K \cdot K\right)\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
          6. *-lowering-*.f6486.0%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{+.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{*.f64}\left(\frac{1}{4}, \mathsf{*.f64}\left(J, \mathsf{*.f64}\left(K, K\right)\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
        7. Simplified86.0%

          \[\leadsto \color{blue}{\left(-2 \cdot J + 0.25 \cdot \left(J \cdot \left(K \cdot K\right)\right)\right)} \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
      5. Recombined 5 regimes into one program.
      6. Final simplification68.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\cos \left(\frac{K}{2}\right) \leq -0.05:\\ \;\;\;\;U\\ \mathbf{elif}\;\cos \left(\frac{K}{2}\right) \leq 0.2:\\ \;\;\;\;\frac{1}{\frac{1}{\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}\\ \mathbf{elif}\;\cos \left(\frac{K}{2}\right) \leq 0.925:\\ \;\;\;\;0 - U\\ \mathbf{elif}\;\cos \left(\frac{K}{2}\right) \leq 0.99996:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \cdot \left(-2 \cdot J + 0.25 \cdot \left(J \cdot \left(K \cdot K\right)\right)\right)\\ \end{array} \]
      7. Add Preprocessing

      Alternative 3: 88.8% accurate, 1.3× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 1.32 \cdot 10^{-256}:\\ \;\;\;\;0 - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot t\_0\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{J\_m \cdot 2}}{t\_0}\right)\\ \end{array} \end{array} \end{array} \]
      U_m = (fabs.f64 U)
      J\_m = (fabs.f64 J)
      J\_s = (copysign.f64 #s(literal 1 binary64) J)
      (FPCore (J_s J_m K U_m)
       :precision binary64
       (let* ((t_0 (cos (/ K 2.0))))
         (*
          J_s
          (if (<= J_m 1.32e-256)
            (- 0.0 U_m)
            (* (* (* -2.0 J_m) t_0) (hypot 1.0 (/ (/ U_m (* J_m 2.0)) t_0)))))))
      U_m = fabs(U);
      J\_m = fabs(J);
      J\_s = copysign(1.0, J);
      double code(double J_s, double J_m, double K, double U_m) {
      	double t_0 = cos((K / 2.0));
      	double tmp;
      	if (J_m <= 1.32e-256) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = ((-2.0 * J_m) * t_0) * hypot(1.0, ((U_m / (J_m * 2.0)) / t_0));
      	}
      	return J_s * tmp;
      }
      
      U_m = Math.abs(U);
      J\_m = Math.abs(J);
      J\_s = Math.copySign(1.0, J);
      public static double code(double J_s, double J_m, double K, double U_m) {
      	double t_0 = Math.cos((K / 2.0));
      	double tmp;
      	if (J_m <= 1.32e-256) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = ((-2.0 * J_m) * t_0) * Math.hypot(1.0, ((U_m / (J_m * 2.0)) / t_0));
      	}
      	return J_s * tmp;
      }
      
      U_m = math.fabs(U)
      J\_m = math.fabs(J)
      J\_s = math.copysign(1.0, J)
      def code(J_s, J_m, K, U_m):
      	t_0 = math.cos((K / 2.0))
      	tmp = 0
      	if J_m <= 1.32e-256:
      		tmp = 0.0 - U_m
      	else:
      		tmp = ((-2.0 * J_m) * t_0) * math.hypot(1.0, ((U_m / (J_m * 2.0)) / t_0))
      	return J_s * tmp
      
      U_m = abs(U)
      J\_m = abs(J)
      J\_s = copysign(1.0, J)
      function code(J_s, J_m, K, U_m)
      	t_0 = cos(Float64(K / 2.0))
      	tmp = 0.0
      	if (J_m <= 1.32e-256)
      		tmp = Float64(0.0 - U_m);
      	else
      		tmp = Float64(Float64(Float64(-2.0 * J_m) * t_0) * hypot(1.0, Float64(Float64(U_m / Float64(J_m * 2.0)) / t_0)));
      	end
      	return Float64(J_s * tmp)
      end
      
      U_m = abs(U);
      J\_m = abs(J);
      J\_s = sign(J) * abs(1.0);
      function tmp_2 = code(J_s, J_m, K, U_m)
      	t_0 = cos((K / 2.0));
      	tmp = 0.0;
      	if (J_m <= 1.32e-256)
      		tmp = 0.0 - U_m;
      	else
      		tmp = ((-2.0 * J_m) * t_0) * hypot(1.0, ((U_m / (J_m * 2.0)) / t_0));
      	end
      	tmp_2 = J_s * tmp;
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      J\_m = N[Abs[J], $MachinePrecision]
      J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[J$95$s_, J$95$m_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(J$95$s * If[LessEqual[J$95$m, 1.32e-256], N[(0.0 - U$95$m), $MachinePrecision], N[(N[(N[(-2.0 * J$95$m), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / N[(J$95$m * 2.0), $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]]
      
      \begin{array}{l}
      U_m = \left|U\right|
      \\
      J\_m = \left|J\right|
      \\
      J\_s = \mathsf{copysign}\left(1, J\right)
      
      \\
      \begin{array}{l}
      t_0 := \cos \left(\frac{K}{2}\right)\\
      J\_s \cdot \begin{array}{l}
      \mathbf{if}\;J\_m \leq 1.32 \cdot 10^{-256}:\\
      \;\;\;\;0 - U\_m\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot t\_0\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{J\_m \cdot 2}}{t\_0}\right)\\
      
      
      \end{array}
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if J < 1.32e-256

        1. Initial program 62.8%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around 0

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

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-sub0N/A

            \[\leadsto 0 - \color{blue}{U} \]
          3. --lowering--.f6432.8%

            \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
        5. Simplified32.8%

          \[\leadsto \color{blue}{0 - U} \]
        6. Step-by-step derivation
          1. sub0-negN/A

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-lowering-neg.f6432.8%

            \[\leadsto \mathsf{neg.f64}\left(U\right) \]
        7. Applied egg-rr32.8%

          \[\leadsto \color{blue}{-U} \]

        if 1.32e-256 < J

        1. Initial program 82.3%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Step-by-step derivation
          1. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right), \color{blue}{\left(\sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\right)}\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\left(-2 \cdot J\right), \cos \left(\frac{K}{2}\right)\right), \left(\sqrt{\color{blue}{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}}\right)\right) \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \cos \left(\frac{K}{2}\right)\right), \left(\sqrt{\color{blue}{1} + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}\right)\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\left(\frac{K}{2}\right)\right)\right), \left(\sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}}}\right)\right) \]
          5. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\sqrt{1 + {\color{blue}{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}}^{2}}\right)\right) \]
          6. unpow2N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}\right)\right) \]
          7. hypot-1-defN/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \left(\mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}\right)\right)\right) \]
          8. hypot-lowering-hypot.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \color{blue}{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}\right)\right) \]
          9. associate-/r*N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \left(\frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(\frac{K}{2}\right)}}\right)\right)\right) \]
          10. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\left(\frac{U}{2 \cdot J}\right), \color{blue}{\cos \left(\frac{K}{2}\right)}\right)\right)\right) \]
          11. /-lowering-/.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \left(2 \cdot J\right)\right), \cos \color{blue}{\left(\frac{K}{2}\right)}\right)\right)\right) \]
          12. *-commutativeN/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \left(J \cdot 2\right)\right), \cos \left(\frac{K}{\color{blue}{2}}\right)\right)\right)\right) \]
          13. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \cos \left(\frac{K}{\color{blue}{2}}\right)\right)\right)\right) \]
          14. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\left(\frac{K}{2}\right)\right)\right)\right)\right) \]
          15. /-lowering-/.f6494.2%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{hypot.f64}\left(1, \mathsf{/.f64}\left(\mathsf{/.f64}\left(U, \mathsf{*.f64}\left(J, 2\right)\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right)\right)\right) \]
        3. Simplified94.2%

          \[\leadsto \color{blue}{\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
        4. Add Preprocessing
      3. Recombined 2 regimes into one program.
      4. Final simplification61.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 1.32 \cdot 10^{-256}:\\ \;\;\;\;0 - U\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 4: 66.6% accurate, 3.7× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 7.5 \cdot 10^{-61}:\\ \;\;\;\;0 - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \end{array} \]
      U_m = (fabs.f64 U)
      J\_m = (fabs.f64 J)
      J\_s = (copysign.f64 #s(literal 1 binary64) J)
      (FPCore (J_s J_m K U_m)
       :precision binary64
       (* J_s (if (<= J_m 7.5e-61) (- 0.0 U_m) (* (* -2.0 J_m) (cos (* K 0.5))))))
      U_m = fabs(U);
      J\_m = fabs(J);
      J\_s = copysign(1.0, J);
      double code(double J_s, double J_m, double K, double U_m) {
      	double tmp;
      	if (J_m <= 7.5e-61) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = (-2.0 * J_m) * cos((K * 0.5));
      	}
      	return J_s * tmp;
      }
      
      U_m = abs(u)
      J\_m = abs(j)
      J\_s = copysign(1.0d0, j)
      real(8) function code(j_s, j_m, k, u_m)
          real(8), intent (in) :: j_s
          real(8), intent (in) :: j_m
          real(8), intent (in) :: k
          real(8), intent (in) :: u_m
          real(8) :: tmp
          if (j_m <= 7.5d-61) then
              tmp = 0.0d0 - u_m
          else
              tmp = ((-2.0d0) * j_m) * cos((k * 0.5d0))
          end if
          code = j_s * tmp
      end function
      
      U_m = Math.abs(U);
      J\_m = Math.abs(J);
      J\_s = Math.copySign(1.0, J);
      public static double code(double J_s, double J_m, double K, double U_m) {
      	double tmp;
      	if (J_m <= 7.5e-61) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = (-2.0 * J_m) * Math.cos((K * 0.5));
      	}
      	return J_s * tmp;
      }
      
      U_m = math.fabs(U)
      J\_m = math.fabs(J)
      J\_s = math.copysign(1.0, J)
      def code(J_s, J_m, K, U_m):
      	tmp = 0
      	if J_m <= 7.5e-61:
      		tmp = 0.0 - U_m
      	else:
      		tmp = (-2.0 * J_m) * math.cos((K * 0.5))
      	return J_s * tmp
      
      U_m = abs(U)
      J\_m = abs(J)
      J\_s = copysign(1.0, J)
      function code(J_s, J_m, K, U_m)
      	tmp = 0.0
      	if (J_m <= 7.5e-61)
      		tmp = Float64(0.0 - U_m);
      	else
      		tmp = Float64(Float64(-2.0 * J_m) * cos(Float64(K * 0.5)));
      	end
      	return Float64(J_s * tmp)
      end
      
      U_m = abs(U);
      J\_m = abs(J);
      J\_s = sign(J) * abs(1.0);
      function tmp_2 = code(J_s, J_m, K, U_m)
      	tmp = 0.0;
      	if (J_m <= 7.5e-61)
      		tmp = 0.0 - U_m;
      	else
      		tmp = (-2.0 * J_m) * cos((K * 0.5));
      	end
      	tmp_2 = J_s * tmp;
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      J\_m = N[Abs[J], $MachinePrecision]
      J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[J$95$s_, J$95$m_, K_, U$95$m_] := N[(J$95$s * If[LessEqual[J$95$m, 7.5e-61], N[(0.0 - U$95$m), $MachinePrecision], N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
      
      \begin{array}{l}
      U_m = \left|U\right|
      \\
      J\_m = \left|J\right|
      \\
      J\_s = \mathsf{copysign}\left(1, J\right)
      
      \\
      J\_s \cdot \begin{array}{l}
      \mathbf{if}\;J\_m \leq 7.5 \cdot 10^{-61}:\\
      \;\;\;\;0 - U\_m\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if J < 7.50000000000000047e-61

        1. Initial program 62.2%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around 0

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

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-sub0N/A

            \[\leadsto 0 - \color{blue}{U} \]
          3. --lowering--.f6432.5%

            \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
        5. Simplified32.5%

          \[\leadsto \color{blue}{0 - U} \]
        6. Step-by-step derivation
          1. sub0-negN/A

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-lowering-neg.f6432.5%

            \[\leadsto \mathsf{neg.f64}\left(U\right) \]
        7. Applied egg-rr32.5%

          \[\leadsto \color{blue}{-U} \]

        if 7.50000000000000047e-61 < J

        1. Initial program 94.9%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around inf

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

            \[\leadsto \left(-2 \cdot J\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)} \]
          2. *-commutativeN/A

            \[\leadsto \cos \left(\frac{1}{2} \cdot K\right) \cdot \color{blue}{\left(-2 \cdot J\right)} \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\left(-2 \cdot J\right)}\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\left(\frac{1}{2} \cdot K\right)\right), \left(\color{blue}{-2} \cdot J\right)\right) \]
          5. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \left(-2 \cdot J\right)\right) \]
          6. *-lowering-*.f6472.8%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
        5. Simplified72.8%

          \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification44.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 7.5 \cdot 10^{-61}:\\ \;\;\;\;0 - U\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 5: 50.1% accurate, 52.4× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 1.55 \cdot 10^{+77}:\\ \;\;\;\;0 - U\_m\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\_m\\ \end{array} \end{array} \]
      U_m = (fabs.f64 U)
      J\_m = (fabs.f64 J)
      J\_s = (copysign.f64 #s(literal 1 binary64) J)
      (FPCore (J_s J_m K U_m)
       :precision binary64
       (* J_s (if (<= J_m 1.55e+77) (- 0.0 U_m) (* -2.0 J_m))))
      U_m = fabs(U);
      J\_m = fabs(J);
      J\_s = copysign(1.0, J);
      double code(double J_s, double J_m, double K, double U_m) {
      	double tmp;
      	if (J_m <= 1.55e+77) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = -2.0 * J_m;
      	}
      	return J_s * tmp;
      }
      
      U_m = abs(u)
      J\_m = abs(j)
      J\_s = copysign(1.0d0, j)
      real(8) function code(j_s, j_m, k, u_m)
          real(8), intent (in) :: j_s
          real(8), intent (in) :: j_m
          real(8), intent (in) :: k
          real(8), intent (in) :: u_m
          real(8) :: tmp
          if (j_m <= 1.55d+77) then
              tmp = 0.0d0 - u_m
          else
              tmp = (-2.0d0) * j_m
          end if
          code = j_s * tmp
      end function
      
      U_m = Math.abs(U);
      J\_m = Math.abs(J);
      J\_s = Math.copySign(1.0, J);
      public static double code(double J_s, double J_m, double K, double U_m) {
      	double tmp;
      	if (J_m <= 1.55e+77) {
      		tmp = 0.0 - U_m;
      	} else {
      		tmp = -2.0 * J_m;
      	}
      	return J_s * tmp;
      }
      
      U_m = math.fabs(U)
      J\_m = math.fabs(J)
      J\_s = math.copysign(1.0, J)
      def code(J_s, J_m, K, U_m):
      	tmp = 0
      	if J_m <= 1.55e+77:
      		tmp = 0.0 - U_m
      	else:
      		tmp = -2.0 * J_m
      	return J_s * tmp
      
      U_m = abs(U)
      J\_m = abs(J)
      J\_s = copysign(1.0, J)
      function code(J_s, J_m, K, U_m)
      	tmp = 0.0
      	if (J_m <= 1.55e+77)
      		tmp = Float64(0.0 - U_m);
      	else
      		tmp = Float64(-2.0 * J_m);
      	end
      	return Float64(J_s * tmp)
      end
      
      U_m = abs(U);
      J\_m = abs(J);
      J\_s = sign(J) * abs(1.0);
      function tmp_2 = code(J_s, J_m, K, U_m)
      	tmp = 0.0;
      	if (J_m <= 1.55e+77)
      		tmp = 0.0 - U_m;
      	else
      		tmp = -2.0 * J_m;
      	end
      	tmp_2 = J_s * tmp;
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      J\_m = N[Abs[J], $MachinePrecision]
      J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[J$95$s_, J$95$m_, K_, U$95$m_] := N[(J$95$s * If[LessEqual[J$95$m, 1.55e+77], N[(0.0 - U$95$m), $MachinePrecision], N[(-2.0 * J$95$m), $MachinePrecision]]), $MachinePrecision]
      
      \begin{array}{l}
      U_m = \left|U\right|
      \\
      J\_m = \left|J\right|
      \\
      J\_s = \mathsf{copysign}\left(1, J\right)
      
      \\
      J\_s \cdot \begin{array}{l}
      \mathbf{if}\;J\_m \leq 1.55 \cdot 10^{+77}:\\
      \;\;\;\;0 - U\_m\\
      
      \mathbf{else}:\\
      \;\;\;\;-2 \cdot J\_m\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if J < 1.54999999999999999e77

        1. Initial program 64.3%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around 0

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

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-sub0N/A

            \[\leadsto 0 - \color{blue}{U} \]
          3. --lowering--.f6433.2%

            \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
        5. Simplified33.2%

          \[\leadsto \color{blue}{0 - U} \]
        6. Step-by-step derivation
          1. sub0-negN/A

            \[\leadsto \mathsf{neg}\left(U\right) \]
          2. neg-lowering-neg.f6433.2%

            \[\leadsto \mathsf{neg.f64}\left(U\right) \]
        7. Applied egg-rr33.2%

          \[\leadsto \color{blue}{-U} \]

        if 1.54999999999999999e77 < J

        1. Initial program 98.3%

          \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
        2. Add Preprocessing
        3. Taylor expanded in J around inf

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

            \[\leadsto \left(-2 \cdot J\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)} \]
          2. *-commutativeN/A

            \[\leadsto \cos \left(\frac{1}{2} \cdot K\right) \cdot \color{blue}{\left(-2 \cdot J\right)} \]
          3. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\left(-2 \cdot J\right)}\right) \]
          4. cos-lowering-cos.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\left(\frac{1}{2} \cdot K\right)\right), \left(\color{blue}{-2} \cdot J\right)\right) \]
          5. *-lowering-*.f64N/A

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \left(-2 \cdot J\right)\right) \]
          6. *-lowering-*.f6485.1%

            \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
        5. Simplified85.1%

          \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]
        6. Taylor expanded in K around 0

          \[\leadsto \color{blue}{-2 \cdot J} \]
        7. Step-by-step derivation
          1. *-lowering-*.f6452.5%

            \[\leadsto \mathsf{*.f64}\left(-2, \color{blue}{J}\right) \]
        8. Simplified52.5%

          \[\leadsto \color{blue}{-2 \cdot J} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification37.5%

        \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 1.55 \cdot 10^{+77}:\\ \;\;\;\;0 - U\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\\ \end{array} \]
      5. Add Preprocessing

      Alternative 6: 39.7% accurate, 140.0× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \left(0 - U\_m\right) \end{array} \]
      U_m = (fabs.f64 U)
      J\_m = (fabs.f64 J)
      J\_s = (copysign.f64 #s(literal 1 binary64) J)
      (FPCore (J_s J_m K U_m) :precision binary64 (* J_s (- 0.0 U_m)))
      U_m = fabs(U);
      J\_m = fabs(J);
      J\_s = copysign(1.0, J);
      double code(double J_s, double J_m, double K, double U_m) {
      	return J_s * (0.0 - U_m);
      }
      
      U_m = abs(u)
      J\_m = abs(j)
      J\_s = copysign(1.0d0, j)
      real(8) function code(j_s, j_m, k, u_m)
          real(8), intent (in) :: j_s
          real(8), intent (in) :: j_m
          real(8), intent (in) :: k
          real(8), intent (in) :: u_m
          code = j_s * (0.0d0 - u_m)
      end function
      
      U_m = Math.abs(U);
      J\_m = Math.abs(J);
      J\_s = Math.copySign(1.0, J);
      public static double code(double J_s, double J_m, double K, double U_m) {
      	return J_s * (0.0 - U_m);
      }
      
      U_m = math.fabs(U)
      J\_m = math.fabs(J)
      J\_s = math.copysign(1.0, J)
      def code(J_s, J_m, K, U_m):
      	return J_s * (0.0 - U_m)
      
      U_m = abs(U)
      J\_m = abs(J)
      J\_s = copysign(1.0, J)
      function code(J_s, J_m, K, U_m)
      	return Float64(J_s * Float64(0.0 - U_m))
      end
      
      U_m = abs(U);
      J\_m = abs(J);
      J\_s = sign(J) * abs(1.0);
      function tmp = code(J_s, J_m, K, U_m)
      	tmp = J_s * (0.0 - U_m);
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      J\_m = N[Abs[J], $MachinePrecision]
      J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[J$95$s_, J$95$m_, K_, U$95$m_] := N[(J$95$s * N[(0.0 - U$95$m), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      U_m = \left|U\right|
      \\
      J\_m = \left|J\right|
      \\
      J\_s = \mathsf{copysign}\left(1, J\right)
      
      \\
      J\_s \cdot \left(0 - U\_m\right)
      \end{array}
      
      Derivation
      1. Initial program 71.9%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Taylor expanded in J around 0

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

          \[\leadsto \mathsf{neg}\left(U\right) \]
        2. neg-sub0N/A

          \[\leadsto 0 - \color{blue}{U} \]
        3. --lowering--.f6428.7%

          \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
      5. Simplified28.7%

        \[\leadsto \color{blue}{0 - U} \]
      6. Step-by-step derivation
        1. sub0-negN/A

          \[\leadsto \mathsf{neg}\left(U\right) \]
        2. neg-lowering-neg.f6428.7%

          \[\leadsto \mathsf{neg.f64}\left(U\right) \]
      7. Applied egg-rr28.7%

        \[\leadsto \color{blue}{-U} \]
      8. Final simplification28.7%

        \[\leadsto 0 - U \]
      9. Add Preprocessing

      Alternative 7: 14.4% accurate, 420.0× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot U\_m \end{array} \]
      U_m = (fabs.f64 U)
      J\_m = (fabs.f64 J)
      J\_s = (copysign.f64 #s(literal 1 binary64) J)
      (FPCore (J_s J_m K U_m) :precision binary64 (* J_s U_m))
      U_m = fabs(U);
      J\_m = fabs(J);
      J\_s = copysign(1.0, J);
      double code(double J_s, double J_m, double K, double U_m) {
      	return J_s * U_m;
      }
      
      U_m = abs(u)
      J\_m = abs(j)
      J\_s = copysign(1.0d0, j)
      real(8) function code(j_s, j_m, k, u_m)
          real(8), intent (in) :: j_s
          real(8), intent (in) :: j_m
          real(8), intent (in) :: k
          real(8), intent (in) :: u_m
          code = j_s * u_m
      end function
      
      U_m = Math.abs(U);
      J\_m = Math.abs(J);
      J\_s = Math.copySign(1.0, J);
      public static double code(double J_s, double J_m, double K, double U_m) {
      	return J_s * U_m;
      }
      
      U_m = math.fabs(U)
      J\_m = math.fabs(J)
      J\_s = math.copysign(1.0, J)
      def code(J_s, J_m, K, U_m):
      	return J_s * U_m
      
      U_m = abs(U)
      J\_m = abs(J)
      J\_s = copysign(1.0, J)
      function code(J_s, J_m, K, U_m)
      	return Float64(J_s * U_m)
      end
      
      U_m = abs(U);
      J\_m = abs(J);
      J\_s = sign(J) * abs(1.0);
      function tmp = code(J_s, J_m, K, U_m)
      	tmp = J_s * U_m;
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      J\_m = N[Abs[J], $MachinePrecision]
      J\_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[J]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
      code[J$95$s_, J$95$m_, K_, U$95$m_] := N[(J$95$s * U$95$m), $MachinePrecision]
      
      \begin{array}{l}
      U_m = \left|U\right|
      \\
      J\_m = \left|J\right|
      \\
      J\_s = \mathsf{copysign}\left(1, J\right)
      
      \\
      J\_s \cdot U\_m
      \end{array}
      
      Derivation
      1. Initial program 71.9%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Taylor expanded in U around -inf

        \[\leadsto \color{blue}{U} \]
      4. Step-by-step derivation
        1. Simplified26.8%

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

        Reproduce

        ?
        herbie shell --seed 2024138 
        (FPCore (J K U)
          :name "Maksimov and Kolovsky, Equation (3)"
          :precision binary64
          (* (* (* -2.0 J) (cos (/ K 2.0))) (sqrt (+ 1.0 (pow (/ U (* (* 2.0 J) (cos (/ K 2.0)))) 2.0)))))