Maksimov and Kolovsky, Equation (3)

Percentage Accurate: 73.6% → 99.6%
Time: 11.2s
Alternatives: 9
Speedup: 1.9×

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 9 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: 73.6% 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: 99.6% accurate, 0.3× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\_m\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J\_m \cdot 2\right)}\right)}^{2}}\\ J\_s \cdot \begin{array}{l} \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;0 - U\_m\\ \mathbf{elif}\;t\_1 \leq 10^{+298}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;U\_m\\ \end{array} \end{array} \end{array} \]
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+298) 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+298) {
		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+298) {
		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+298:
		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+298)
		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+298)
		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+298], 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^{+298}:\\
\;\;\;\;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 5.1%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    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--.f6446.1%

        \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
    5. Simplified46.1%

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

        \[\leadsto \mathsf{neg}\left(U\right) \]
      2. neg-lowering-neg.f6446.1%

        \[\leadsto \mathsf{neg.f64}\left(U\right) \]
    7. Applied egg-rr46.1%

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

    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))))) < 9.9999999999999996e297

    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 9.9999999999999996e297 < (*.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 17.5%

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

      \[\leadsto \color{blue}{U} \]
    4. Step-by-step derivation
      1. Simplified53.0%

        \[\leadsto \color{blue}{U} \]
    5. Recombined 3 regimes into one program.
    6. Final simplification85.2%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;0 - U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 10^{+298}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;U\\ \end{array} \]
    7. Add Preprocessing

    Alternative 2: 79.9% accurate, 1.2× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 5.4 \cdot 10^{-181}:\\ \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U\_m}{\left(-2 \cdot J\_m\right) \cdot \left(\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \frac{K}{2}\right)\right) \cdot \frac{J\_m \cdot 2}{U\_m}\right)}}\\ \end{array} \end{array} \]
    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 5.4e-181)
        (- (* J_m (/ (* -2.0 J_m) U_m)) U_m)
        (*
         (* (* -2.0 J_m) (cos (/ K 2.0)))
         (sqrt
          (-
           1.0
           (/
            U_m
            (*
             (* -2.0 J_m)
             (*
              (+ 0.5 (* 0.5 (cos (* 2.0 (/ K 2.0)))))
              (/ (* J_m 2.0) 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) {
    	double tmp;
    	if (J_m <= 5.4e-181) {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - U_m;
    	} else {
    		tmp = ((-2.0 * J_m) * cos((K / 2.0))) * sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((0.5 + (0.5 * cos((2.0 * (K / 2.0))))) * ((J_m * 2.0) / U_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 <= 5.4d-181) then
            tmp = (j_m * (((-2.0d0) * j_m) / u_m)) - u_m
        else
            tmp = (((-2.0d0) * j_m) * cos((k / 2.0d0))) * sqrt((1.0d0 - (u_m / (((-2.0d0) * j_m) * ((0.5d0 + (0.5d0 * cos((2.0d0 * (k / 2.0d0))))) * ((j_m * 2.0d0) / u_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 <= 5.4e-181) {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - U_m;
    	} else {
    		tmp = ((-2.0 * J_m) * Math.cos((K / 2.0))) * Math.sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((0.5 + (0.5 * Math.cos((2.0 * (K / 2.0))))) * ((J_m * 2.0) / 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):
    	tmp = 0
    	if J_m <= 5.4e-181:
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - U_m
    	else:
    		tmp = ((-2.0 * J_m) * math.cos((K / 2.0))) * math.sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((0.5 + (0.5 * math.cos((2.0 * (K / 2.0))))) * ((J_m * 2.0) / 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)
    	tmp = 0.0
    	if (J_m <= 5.4e-181)
    		tmp = Float64(Float64(J_m * Float64(Float64(-2.0 * J_m) / U_m)) - U_m);
    	else
    		tmp = Float64(Float64(Float64(-2.0 * J_m) * cos(Float64(K / 2.0))) * sqrt(Float64(1.0 - Float64(U_m / Float64(Float64(-2.0 * J_m) * Float64(Float64(0.5 + Float64(0.5 * cos(Float64(2.0 * Float64(K / 2.0))))) * Float64(Float64(J_m * 2.0) / 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)
    	tmp = 0.0;
    	if (J_m <= 5.4e-181)
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - U_m;
    	else
    		tmp = ((-2.0 * J_m) * cos((K / 2.0))) * sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((0.5 + (0.5 * cos((2.0 * (K / 2.0))))) * ((J_m * 2.0) / 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_] := N[(J$95$s * If[LessEqual[J$95$m, 5.4e-181], N[(N[(J$95$m * N[(N[(-2.0 * J$95$m), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision] - U$95$m), $MachinePrecision], N[(N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(1.0 - N[(U$95$m / N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[(N[(0.5 + N[(0.5 * N[Cos[N[(2.0 * N[(K / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(J$95$m * 2.0), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision]), $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)
    
    \\
    J\_s \cdot \begin{array}{l}
    \mathbf{if}\;J\_m \leq 5.4 \cdot 10^{-181}:\\
    \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - U\_m\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U\_m}{\left(-2 \cdot J\_m\right) \cdot \left(\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \frac{K}{2}\right)\right) \cdot \frac{J\_m \cdot 2}{U\_m}\right)}}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if J < 5.3999999999999999e-181

      1. Initial program 66.2%

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

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

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

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

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

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \left(\frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        6. associate-*r/N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\left(\frac{1}{4} \cdot {U}^{2}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        8. *-commutativeN/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({U}^{2}\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        10. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        12. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        14. *-lowering-*.f6425.7%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified25.7%

        \[\leadsto \color{blue}{\sqrt{1 + \frac{\left(U \cdot U\right) \cdot 0.25}{J \cdot J}} \cdot \left(-2 \cdot J\right)} \]
      6. Taylor expanded in J around 0

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2}}{U} + -1 \cdot U} \]
      7. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} + \left(\mathsf{neg}\left(U\right)\right) \]
        2. unsub-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} - \color{blue}{U} \]
        3. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(-2 \cdot \frac{{J}^{2}}{U}\right), \color{blue}{U}\right) \]
        4. associate-*r/N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{-2 \cdot {J}^{2}}{U}\right), U\right) \]
        5. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left(-2 \cdot {J}^{2}\right), U\right), U\right) \]
        6. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left({J}^{2} \cdot -2\right), U\right), U\right) \]
        7. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({J}^{2}\right), -2\right), U\right), U\right) \]
        8. unpow2N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left(J \cdot J\right), -2\right), U\right), U\right) \]
        9. *-lowering-*.f6426.9%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(J, J\right), -2\right), U\right), U\right) \]
      8. Simplified26.9%

        \[\leadsto \color{blue}{\frac{\left(J \cdot J\right) \cdot -2}{U} - U} \]
      9. Step-by-step derivation
        1. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{\left(J \cdot J\right) \cdot -2}{U}\right), \color{blue}{U}\right) \]
        2. associate-*l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(J \cdot -2\right)}{U}\right), U\right) \]
        3. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(-2 \cdot J\right)}{U}\right), U\right) \]
        4. associate-/l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(J \cdot \frac{-2 \cdot J}{U}\right), U\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \left(\frac{-2 \cdot J}{U}\right)\right), U\right) \]
        6. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(-2 \cdot J\right), U\right)\right), U\right) \]
        7. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(J \cdot -2\right), U\right)\right), U\right) \]
        8. *-lowering-*.f6429.4%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\mathsf{*.f64}\left(J, -2\right), U\right)\right), U\right) \]
      10. Applied egg-rr29.4%

        \[\leadsto \color{blue}{J \cdot \frac{J \cdot -2}{U} - U} \]

      if 5.3999999999999999e-181 < J

      1. Initial program 86.5%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. unpow2N/A

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\left(\frac{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}{U} \cdot \left(\mathsf{neg}\left(\cos \left(\frac{K}{2}\right) \cdot \left(2 \cdot J\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
        11. distribute-rgt-neg-inN/A

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\left(\frac{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}{U} \cdot \left(\cos \left(\frac{K}{2}\right) \cdot \left(\mathsf{neg}\left(2 \cdot J\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
      4. Applied egg-rr86.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{-\left(\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \frac{K}{2}\right)\right) \cdot \frac{J \cdot 2}{U}\right) \cdot \left(-2 \cdot J\right)}}} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification51.4%

      \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 5.4 \cdot 10^{-181}:\\ \;\;\;\;J \cdot \frac{-2 \cdot J}{U} - U\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U}{\left(-2 \cdot J\right) \cdot \left(\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \frac{K}{2}\right)\right) \cdot \frac{J \cdot 2}{U}\right)}}\\ \end{array} \]
    5. Add Preprocessing

    Alternative 3: 74.3% accurate, 1.9× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 3.9 \cdot 10^{-128}:\\ \;\;\;\;J\_m \cdot \left(\left(-2 \cdot J\_m\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U\_m}\right) - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U\_m}{\left(-2 \cdot J\_m\right) \cdot \frac{J\_m \cdot 2}{U\_m}}}\\ \end{array} \end{array} \]
    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 3.9e-128)
        (- (* J_m (* (* -2.0 J_m) (/ (+ 0.5 (* 0.5 (cos K))) U_m))) U_m)
        (*
         (* (* -2.0 J_m) (cos (/ K 2.0)))
         (sqrt (- 1.0 (/ U_m (* (* -2.0 J_m) (/ (* J_m 2.0) 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) {
    	double tmp;
    	if (J_m <= 3.9e-128) {
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * cos(K))) / U_m))) - U_m;
    	} else {
    		tmp = ((-2.0 * J_m) * cos((K / 2.0))) * sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((J_m * 2.0) / U_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 <= 3.9d-128) then
            tmp = (j_m * (((-2.0d0) * j_m) * ((0.5d0 + (0.5d0 * cos(k))) / u_m))) - u_m
        else
            tmp = (((-2.0d0) * j_m) * cos((k / 2.0d0))) * sqrt((1.0d0 - (u_m / (((-2.0d0) * j_m) * ((j_m * 2.0d0) / u_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 <= 3.9e-128) {
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * Math.cos(K))) / U_m))) - U_m;
    	} else {
    		tmp = ((-2.0 * J_m) * Math.cos((K / 2.0))) * Math.sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((J_m * 2.0) / 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):
    	tmp = 0
    	if J_m <= 3.9e-128:
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * math.cos(K))) / U_m))) - U_m
    	else:
    		tmp = ((-2.0 * J_m) * math.cos((K / 2.0))) * math.sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((J_m * 2.0) / 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)
    	tmp = 0.0
    	if (J_m <= 3.9e-128)
    		tmp = Float64(Float64(J_m * Float64(Float64(-2.0 * J_m) * Float64(Float64(0.5 + Float64(0.5 * cos(K))) / U_m))) - U_m);
    	else
    		tmp = Float64(Float64(Float64(-2.0 * J_m) * cos(Float64(K / 2.0))) * sqrt(Float64(1.0 - Float64(U_m / Float64(Float64(-2.0 * J_m) * Float64(Float64(J_m * 2.0) / 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)
    	tmp = 0.0;
    	if (J_m <= 3.9e-128)
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * cos(K))) / U_m))) - U_m;
    	else
    		tmp = ((-2.0 * J_m) * cos((K / 2.0))) * sqrt((1.0 - (U_m / ((-2.0 * J_m) * ((J_m * 2.0) / 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_] := N[(J$95$s * If[LessEqual[J$95$m, 3.9e-128], N[(N[(J$95$m * N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[(N[(0.5 + N[(0.5 * N[Cos[K], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - U$95$m), $MachinePrecision], N[(N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(1.0 - N[(U$95$m / N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[(N[(J$95$m * 2.0), $MachinePrecision] / U$95$m), $MachinePrecision]), $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)
    
    \\
    J\_s \cdot \begin{array}{l}
    \mathbf{if}\;J\_m \leq 3.9 \cdot 10^{-128}:\\
    \;\;\;\;J\_m \cdot \left(\left(-2 \cdot J\_m\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U\_m}\right) - U\_m\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(\left(-2 \cdot J\_m\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U\_m}{\left(-2 \cdot J\_m\right) \cdot \frac{J\_m \cdot 2}{U\_m}}}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if J < 3.89999999999999997e-128

      1. Initial program 66.4%

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

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} + -1 \cdot U} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} + \left(\mathsf{neg}\left(U\right)\right) \]
        2. unsub-negN/A

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

          \[\leadsto \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} \cdot -2 - U \]
        4. associate-/l*N/A

          \[\leadsto \left({J}^{2} \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right) \cdot -2 - U \]
        5. associate-*r*N/A

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

          \[\leadsto {J}^{2} \cdot \left(-2 \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right) - U \]
        7. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left({J}^{2} \cdot \left(-2 \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right)\right), \color{blue}{U}\right) \]
      5. Simplified28.2%

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

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

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

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\left(\frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} \cdot \left(-2 \cdot J\right)\right), J\right), U\right) \]
      7. Applied egg-rr30.6%

        \[\leadsto \color{blue}{\left(\frac{0.5 + 0.5 \cdot \cos \left(K \cdot 1\right)}{U} \cdot \left(J \cdot -2\right)\right) \cdot J} - U \]

      if 3.89999999999999997e-128 < J

      1. Initial program 89.0%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. unpow2N/A

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\left(\frac{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}{U} \cdot \left(\mathsf{neg}\left(\cos \left(\frac{K}{2}\right) \cdot \left(2 \cdot J\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
        11. distribute-rgt-neg-inN/A

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\left(\frac{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}{U} \cdot \left(\cos \left(\frac{K}{2}\right) \cdot \left(\mathsf{neg}\left(2 \cdot J\right)\right)\right)\right)\right)\right)\right)\right)\right) \]
      4. Applied egg-rr88.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{-\left(\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \frac{K}{2}\right)\right) \cdot \frac{J \cdot 2}{U}\right) \cdot \left(-2 \cdot J\right)}}} \]
      5. Taylor expanded in K around 0

        \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\color{blue}{\left(2 \cdot \frac{J}{U}\right)}, \mathsf{*.f64}\left(-2, J\right)\right)\right)\right)\right)\right)\right) \]
      6. Step-by-step derivation
        1. associate-*r/N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(\left(2 \cdot J\right), U\right), \mathsf{*.f64}\left(-2, J\right)\right)\right)\right)\right)\right)\right) \]
        3. *-lowering-*.f6479.8%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(-2, J\right), \mathsf{cos.f64}\left(\mathsf{/.f64}\left(K, 2\right)\right)\right), \mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(U, \mathsf{neg.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(2, J\right), U\right), \mathsf{*.f64}\left(-2, J\right)\right)\right)\right)\right)\right)\right) \]
      7. Simplified79.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \frac{U}{-\color{blue}{\frac{2 \cdot J}{U}} \cdot \left(-2 \cdot J\right)}} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification47.2%

      \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 3.9 \cdot 10^{-128}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot J\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U}\right) - U\\ \mathbf{else}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 - \frac{U}{\left(-2 \cdot J\right) \cdot \frac{J \cdot 2}{U}}}\\ \end{array} \]
    5. Add Preprocessing

    Alternative 4: 67.6% accurate, 3.5× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 9 \cdot 10^{-42}:\\ \;\;\;\;J\_m \cdot \left(\left(-2 \cdot J\_m\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U\_m}\right) - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \end{array} \]
    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 9e-42)
        (- (* J_m (* (* -2.0 J_m) (/ (+ 0.5 (* 0.5 (cos K))) U_m))) 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 <= 9e-42) {
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * cos(K))) / U_m))) - 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 <= 9d-42) then
            tmp = (j_m * (((-2.0d0) * j_m) * ((0.5d0 + (0.5d0 * cos(k))) / u_m))) - 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 <= 9e-42) {
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * Math.cos(K))) / U_m))) - 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 <= 9e-42:
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * math.cos(K))) / U_m))) - 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 <= 9e-42)
    		tmp = Float64(Float64(J_m * Float64(Float64(-2.0 * J_m) * Float64(Float64(0.5 + Float64(0.5 * cos(K))) / U_m))) - 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 <= 9e-42)
    		tmp = (J_m * ((-2.0 * J_m) * ((0.5 + (0.5 * cos(K))) / U_m))) - 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, 9e-42], N[(N[(J$95$m * N[(N[(-2.0 * J$95$m), $MachinePrecision] * N[(N[(0.5 + N[(0.5 * N[Cos[K], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 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 9 \cdot 10^{-42}:\\
    \;\;\;\;J\_m \cdot \left(\left(-2 \cdot J\_m\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U\_m}\right) - 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 < 9e-42

      1. Initial program 66.5%

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

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} + -1 \cdot U} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} + \left(\mathsf{neg}\left(U\right)\right) \]
        2. unsub-negN/A

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

          \[\leadsto \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} \cdot -2 - U \]
        4. associate-/l*N/A

          \[\leadsto \left({J}^{2} \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right) \cdot -2 - U \]
        5. associate-*r*N/A

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

          \[\leadsto {J}^{2} \cdot \left(-2 \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right) - U \]
        7. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left({J}^{2} \cdot \left(-2 \cdot \frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U}\right)\right), \color{blue}{U}\right) \]
      5. Simplified27.5%

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

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

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

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(\left(\frac{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{U} \cdot \left(-2 \cdot J\right)\right), J\right), U\right) \]
      7. Applied egg-rr29.7%

        \[\leadsto \color{blue}{\left(\frac{0.5 + 0.5 \cdot \cos \left(K \cdot 1\right)}{U} \cdot \left(J \cdot -2\right)\right) \cdot J} - U \]

      if 9e-42 < J

      1. Initial program 95.7%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      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-*.f6476.1%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified76.1%

        \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification41.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 9 \cdot 10^{-42}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot J\right) \cdot \frac{0.5 + 0.5 \cdot \cos K}{U}\right) - U\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 5: 67.6% accurate, 3.7× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;J\_m \leq 4.4 \cdot 10^{-43}:\\ \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\_m\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \end{array} \]
    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 4.4e-43)
        (- (* J_m (/ (* -2.0 J_m) U_m)) 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 <= 4.4e-43) {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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 <= 4.4d-43) then
            tmp = (j_m * (((-2.0d0) * j_m) / u_m)) - 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 <= 4.4e-43) {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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 <= 4.4e-43:
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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 <= 4.4e-43)
    		tmp = Float64(Float64(J_m * Float64(Float64(-2.0 * J_m) / U_m)) - 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 <= 4.4e-43)
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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, 4.4e-43], N[(N[(J$95$m * N[(N[(-2.0 * J$95$m), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision] - 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 4.4 \cdot 10^{-43}:\\
    \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - 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 < 4.39999999999999994e-43

      1. Initial program 66.5%

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

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

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

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

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

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \left(\frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        6. associate-*r/N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\left(\frac{1}{4} \cdot {U}^{2}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        8. *-commutativeN/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({U}^{2}\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        10. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        12. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        14. *-lowering-*.f6427.0%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified27.0%

        \[\leadsto \color{blue}{\sqrt{1 + \frac{\left(U \cdot U\right) \cdot 0.25}{J \cdot J}} \cdot \left(-2 \cdot J\right)} \]
      6. Taylor expanded in J around 0

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2}}{U} + -1 \cdot U} \]
      7. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} + \left(\mathsf{neg}\left(U\right)\right) \]
        2. unsub-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} - \color{blue}{U} \]
        3. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(-2 \cdot \frac{{J}^{2}}{U}\right), \color{blue}{U}\right) \]
        4. associate-*r/N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{-2 \cdot {J}^{2}}{U}\right), U\right) \]
        5. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left(-2 \cdot {J}^{2}\right), U\right), U\right) \]
        6. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left({J}^{2} \cdot -2\right), U\right), U\right) \]
        7. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({J}^{2}\right), -2\right), U\right), U\right) \]
        8. unpow2N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left(J \cdot J\right), -2\right), U\right), U\right) \]
        9. *-lowering-*.f6427.5%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(J, J\right), -2\right), U\right), U\right) \]
      8. Simplified27.5%

        \[\leadsto \color{blue}{\frac{\left(J \cdot J\right) \cdot -2}{U} - U} \]
      9. Step-by-step derivation
        1. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{\left(J \cdot J\right) \cdot -2}{U}\right), \color{blue}{U}\right) \]
        2. associate-*l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(J \cdot -2\right)}{U}\right), U\right) \]
        3. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(-2 \cdot J\right)}{U}\right), U\right) \]
        4. associate-/l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(J \cdot \frac{-2 \cdot J}{U}\right), U\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \left(\frac{-2 \cdot J}{U}\right)\right), U\right) \]
        6. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(-2 \cdot J\right), U\right)\right), U\right) \]
        7. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(J \cdot -2\right), U\right)\right), U\right) \]
        8. *-lowering-*.f6429.7%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\mathsf{*.f64}\left(J, -2\right), U\right)\right), U\right) \]
      10. Applied egg-rr29.7%

        \[\leadsto \color{blue}{J \cdot \frac{J \cdot -2}{U} - U} \]

      if 4.39999999999999994e-43 < J

      1. Initial program 95.7%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      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-*.f6476.1%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified76.1%

        \[\leadsto \color{blue}{\cos \left(0.5 \cdot K\right) \cdot \left(-2 \cdot J\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification41.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 4.4 \cdot 10^{-43}:\\ \;\;\;\;J \cdot \frac{-2 \cdot J}{U} - U\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 6: 50.9% accurate, 30.0× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;U\_m \leq 1.5 \cdot 10^{-89}:\\ \;\;\;\;-2 \cdot J\_m\\ \mathbf{else}:\\ \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - U\_m\\ \end{array} \end{array} \]
    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 (<= U_m 1.5e-89) (* -2.0 J_m) (- (* J_m (/ (* -2.0 J_m) U_m)) 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 tmp;
    	if (U_m <= 1.5e-89) {
    		tmp = -2.0 * J_m;
    	} else {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - U_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 (u_m <= 1.5d-89) then
            tmp = (-2.0d0) * j_m
        else
            tmp = (j_m * (((-2.0d0) * j_m) / u_m)) - u_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 (U_m <= 1.5e-89) {
    		tmp = -2.0 * J_m;
    	} else {
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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):
    	tmp = 0
    	if U_m <= 1.5e-89:
    		tmp = -2.0 * J_m
    	else:
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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)
    	tmp = 0.0
    	if (U_m <= 1.5e-89)
    		tmp = Float64(-2.0 * J_m);
    	else
    		tmp = Float64(Float64(J_m * Float64(Float64(-2.0 * J_m) / U_m)) - 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)
    	tmp = 0.0;
    	if (U_m <= 1.5e-89)
    		tmp = -2.0 * J_m;
    	else
    		tmp = (J_m * ((-2.0 * J_m) / U_m)) - 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_] := N[(J$95$s * If[LessEqual[U$95$m, 1.5e-89], N[(-2.0 * J$95$m), $MachinePrecision], N[(N[(J$95$m * N[(N[(-2.0 * J$95$m), $MachinePrecision] / U$95$m), $MachinePrecision]), $MachinePrecision] - 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 \begin{array}{l}
    \mathbf{if}\;U\_m \leq 1.5 \cdot 10^{-89}:\\
    \;\;\;\;-2 \cdot J\_m\\
    
    \mathbf{else}:\\
    \;\;\;\;J\_m \cdot \frac{-2 \cdot J\_m}{U\_m} - U\_m\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if U < 1.5e-89

      1. Initial program 82.2%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Taylor expanded in J around 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-*.f6462.4%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified62.4%

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

        \[\leadsto \color{blue}{-2 \cdot J} \]
      7. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto J \cdot \color{blue}{-2} \]
        2. *-lowering-*.f6431.6%

          \[\leadsto \mathsf{*.f64}\left(J, \color{blue}{-2}\right) \]
      8. Simplified31.6%

        \[\leadsto \color{blue}{J \cdot -2} \]

      if 1.5e-89 < U

      1. Initial program 56.1%

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

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

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

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

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

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \left(\frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        6. associate-*r/N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\left(\frac{1}{4} \cdot {U}^{2}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        8. *-commutativeN/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({U}^{2}\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        10. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \left({J}^{2}\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        12. unpow2N/A

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

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \left(-2 \cdot J\right)\right) \]
        14. *-lowering-*.f6426.2%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{sqrt.f64}\left(\mathsf{+.f64}\left(1, \mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(U, U\right), \frac{1}{4}\right), \mathsf{*.f64}\left(J, J\right)\right)\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified26.2%

        \[\leadsto \color{blue}{\sqrt{1 + \frac{\left(U \cdot U\right) \cdot 0.25}{J \cdot J}} \cdot \left(-2 \cdot J\right)} \]
      6. Taylor expanded in J around 0

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2}}{U} + -1 \cdot U} \]
      7. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} + \left(\mathsf{neg}\left(U\right)\right) \]
        2. unsub-negN/A

          \[\leadsto -2 \cdot \frac{{J}^{2}}{U} - \color{blue}{U} \]
        3. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(-2 \cdot \frac{{J}^{2}}{U}\right), \color{blue}{U}\right) \]
        4. associate-*r/N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{-2 \cdot {J}^{2}}{U}\right), U\right) \]
        5. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left(-2 \cdot {J}^{2}\right), U\right), U\right) \]
        6. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\left({J}^{2} \cdot -2\right), U\right), U\right) \]
        7. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left({J}^{2}\right), -2\right), U\right), U\right) \]
        8. unpow2N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\left(J \cdot J\right), -2\right), U\right), U\right) \]
        9. *-lowering-*.f6432.9%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(J, J\right), -2\right), U\right), U\right) \]
      8. Simplified32.9%

        \[\leadsto \color{blue}{\frac{\left(J \cdot J\right) \cdot -2}{U} - U} \]
      9. Step-by-step derivation
        1. --lowering--.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{\left(J \cdot J\right) \cdot -2}{U}\right), \color{blue}{U}\right) \]
        2. associate-*l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(J \cdot -2\right)}{U}\right), U\right) \]
        3. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\left(\frac{J \cdot \left(-2 \cdot J\right)}{U}\right), U\right) \]
        4. associate-/l*N/A

          \[\leadsto \mathsf{\_.f64}\left(\left(J \cdot \frac{-2 \cdot J}{U}\right), U\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \left(\frac{-2 \cdot J}{U}\right)\right), U\right) \]
        6. /-lowering-/.f64N/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(-2 \cdot J\right), U\right)\right), U\right) \]
        7. *-commutativeN/A

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\left(J \cdot -2\right), U\right)\right), U\right) \]
        8. *-lowering-*.f6436.3%

          \[\leadsto \mathsf{\_.f64}\left(\mathsf{*.f64}\left(J, \mathsf{/.f64}\left(\mathsf{*.f64}\left(J, -2\right), U\right)\right), U\right) \]
      10. Applied egg-rr36.3%

        \[\leadsto \color{blue}{J \cdot \frac{J \cdot -2}{U} - U} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification33.0%

      \[\leadsto \begin{array}{l} \mathbf{if}\;U \leq 1.5 \cdot 10^{-89}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{else}:\\ \;\;\;\;J \cdot \frac{-2 \cdot J}{U} - U\\ \end{array} \]
    5. Add Preprocessing

    Alternative 7: 50.6% accurate, 52.4× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ J\_m = \left|J\right| \\ J\_s = \mathsf{copysign}\left(1, J\right) \\ J\_s \cdot \begin{array}{l} \mathbf{if}\;U\_m \leq 10^{-93}:\\ \;\;\;\;-2 \cdot J\_m\\ \mathbf{else}:\\ \;\;\;\;0 - U\_m\\ \end{array} \end{array} \]
    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 (<= U_m 1e-93) (* -2.0 J_m) (- 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) {
    	double tmp;
    	if (U_m <= 1e-93) {
    		tmp = -2.0 * J_m;
    	} else {
    		tmp = 0.0 - U_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 (u_m <= 1d-93) then
            tmp = (-2.0d0) * j_m
        else
            tmp = 0.0d0 - u_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 (U_m <= 1e-93) {
    		tmp = -2.0 * J_m;
    	} else {
    		tmp = 0.0 - 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):
    	tmp = 0
    	if U_m <= 1e-93:
    		tmp = -2.0 * J_m
    	else:
    		tmp = 0.0 - 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)
    	tmp = 0.0
    	if (U_m <= 1e-93)
    		tmp = Float64(-2.0 * J_m);
    	else
    		tmp = Float64(0.0 - 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)
    	tmp = 0.0;
    	if (U_m <= 1e-93)
    		tmp = -2.0 * J_m;
    	else
    		tmp = 0.0 - 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_] := N[(J$95$s * If[LessEqual[U$95$m, 1e-93], N[(-2.0 * J$95$m), $MachinePrecision], 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 \begin{array}{l}
    \mathbf{if}\;U\_m \leq 10^{-93}:\\
    \;\;\;\;-2 \cdot J\_m\\
    
    \mathbf{else}:\\
    \;\;\;\;0 - U\_m\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if U < 9.999999999999999e-94

      1. Initial program 82.2%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      2. Add Preprocessing
      3. Taylor expanded in J around 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-*.f6462.4%

          \[\leadsto \mathsf{*.f64}\left(\mathsf{cos.f64}\left(\mathsf{*.f64}\left(\frac{1}{2}, K\right)\right), \mathsf{*.f64}\left(-2, \color{blue}{J}\right)\right) \]
      5. Simplified62.4%

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

        \[\leadsto \color{blue}{-2 \cdot J} \]
      7. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto J \cdot \color{blue}{-2} \]
        2. *-lowering-*.f6431.6%

          \[\leadsto \mathsf{*.f64}\left(J, \color{blue}{-2}\right) \]
      8. Simplified31.6%

        \[\leadsto \color{blue}{J \cdot -2} \]

      if 9.999999999999999e-94 < U

      1. Initial program 56.1%

        \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
      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--.f6436.2%

          \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
      5. Simplified36.2%

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

          \[\leadsto \mathsf{neg}\left(U\right) \]
        2. neg-lowering-neg.f6436.2%

          \[\leadsto \mathsf{neg.f64}\left(U\right) \]
      7. Applied egg-rr36.2%

        \[\leadsto \color{blue}{-U} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification33.0%

      \[\leadsto \begin{array}{l} \mathbf{if}\;U \leq 10^{-93}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{else}:\\ \;\;\;\;0 - U\\ \end{array} \]
    5. Add Preprocessing

    Alternative 8: 39.1% 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 74.0%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    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--.f6427.1%

        \[\leadsto \mathsf{\_.f64}\left(0, \color{blue}{U}\right) \]
    5. Simplified27.1%

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

        \[\leadsto \mathsf{neg}\left(U\right) \]
      2. neg-lowering-neg.f6427.1%

        \[\leadsto \mathsf{neg.f64}\left(U\right) \]
    7. Applied egg-rr27.1%

      \[\leadsto \color{blue}{-U} \]
    8. Final simplification27.1%

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

    Alternative 9: 13.9% 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 74.0%

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

      \[\leadsto \color{blue}{U} \]
    4. Step-by-step derivation
      1. Simplified24.4%

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

      Reproduce

      ?
      herbie shell --seed 2024191 
      (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)))))