Maksimov and Kolovsky, Equation (3)

Percentage Accurate: 73.0% → 99.6%
Time: 12.1s
Alternatives: 13
Speedup: 0.4×

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 13 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: 73.0% 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?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {\cos \left(K \cdot 0.5\right)}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0)))
        (t_1
         (*
          (* (* -2.0 J) t_0)
          (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
   (if (<= t_1 (- INFINITY))
     (- U_m)
     (if (<= t_1 5e+305)
       t_1
       (*
        (- U_m)
        (fma
         -2.0
         (* (pow (cos (* K 0.5)) 2.0) (/ (* J J) (* U_m U_m)))
         -1.0))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double t_0 = cos((K / 2.0));
	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
	double tmp;
	if (t_1 <= -((double) INFINITY)) {
		tmp = -U_m;
	} else if (t_1 <= 5e+305) {
		tmp = t_1;
	} else {
		tmp = -U_m * fma(-2.0, (pow(cos((K * 0.5)), 2.0) * ((J * J) / (U_m * U_m))), -1.0);
	}
	return tmp;
}
U_m = abs(U)
function code(J, K, U_m)
	t_0 = cos(Float64(K / 2.0))
	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
	tmp = 0.0
	if (t_1 <= Float64(-Inf))
		tmp = Float64(-U_m);
	elseif (t_1 <= 5e+305)
		tmp = t_1;
	else
		tmp = Float64(Float64(-U_m) * fma(-2.0, Float64((cos(Float64(K * 0.5)) ^ 2.0) * Float64(Float64(J * J) / Float64(U_m * U_m))), -1.0));
	end
	return tmp
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, 5e+305], t$95$1, N[((-U$95$m) * N[(-2.0 * N[(N[Power[N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision], 2.0], $MachinePrecision] * N[(N[(J * J), $MachinePrecision] / N[(U$95$m * U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}
U_m = \left|U\right|

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

\mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+305}:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {\cos \left(K \cdot 0.5\right)}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\


\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 5.3%

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

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

        \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
      2. lower-neg.f6450.4

        \[\leadsto \color{blue}{-U} \]
    5. Applied rewrites50.4%

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

    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))))) < 5.00000000000000009e305

    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 5.00000000000000009e305 < (*.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 5.8%

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

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

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

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

        \[\leadsto \color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} - 1\right) \]
      4. lower-neg.f64N/A

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

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
      6. metadata-evalN/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \color{blue}{-1}\right) \]
      7. lower-fma.f64N/A

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

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

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

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
      11. lower-pow.f64N/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
      12. lower-cos.f64N/A

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

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
      14. lower-/.f64N/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \color{blue}{\frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
      15. unpow2N/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
      16. lower-*.f64N/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
      17. unpow2N/A

        \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
      18. lower-*.f6446.5

        \[\leadsto \left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
    5. Applied rewrites46.5%

      \[\leadsto \color{blue}{\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification85.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+305}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(K \cdot 0.5\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 82.2% accurate, 0.2× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(-2 \cdot J\right) \cdot t\_0\\ t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ t_3 := \cos \left(K \cdot 0.5\right)\\ t_4 := J \cdot \left(\left(-2 \cdot t\_3\right) \cdot \sqrt{\mathsf{fma}\left(U\_m, \frac{U\_m}{\left(J \cdot 2\right) \cdot \mathsf{fma}\left(J, \cos K, J\right)}, 1\right)}\right)\\ \mathbf{if}\;t\_2 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_2 \leq -3 \cdot 10^{-95}:\\ \;\;\;\;t\_4\\ \mathbf{elif}\;t\_2 \leq 10^{-50}:\\ \;\;\;\;t\_1 \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U\_m}{J}\right)}^{2}}\\ \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;t\_4\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\_m\right) \cdot t\_3}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0)))
        (t_1 (* (* -2.0 J) t_0))
        (t_2 (* t_1 (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0)))))
        (t_3 (cos (* K 0.5)))
        (t_4
         (*
          J
          (*
           (* -2.0 t_3)
           (sqrt (fma U_m (/ U_m (* (* J 2.0) (fma J (cos K) J))) 1.0))))))
   (if (<= t_2 (- INFINITY))
     (- U_m)
     (if (<= t_2 -3e-95)
       t_4
       (if (<= t_2 1e-50)
         (* t_1 (sqrt (+ 1.0 (pow (* 0.5 (/ U_m J)) 2.0))))
         (if (<= t_2 5e+301)
           t_4
           (/ (* (- U_m) t_3) (sqrt (fma (cos K) 0.5 0.5)))))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double t_0 = cos((K / 2.0));
	double t_1 = (-2.0 * J) * t_0;
	double t_2 = t_1 * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
	double t_3 = cos((K * 0.5));
	double t_4 = J * ((-2.0 * t_3) * sqrt(fma(U_m, (U_m / ((J * 2.0) * fma(J, cos(K), J))), 1.0)));
	double tmp;
	if (t_2 <= -((double) INFINITY)) {
		tmp = -U_m;
	} else if (t_2 <= -3e-95) {
		tmp = t_4;
	} else if (t_2 <= 1e-50) {
		tmp = t_1 * sqrt((1.0 + pow((0.5 * (U_m / J)), 2.0)));
	} else if (t_2 <= 5e+301) {
		tmp = t_4;
	} else {
		tmp = (-U_m * t_3) / sqrt(fma(cos(K), 0.5, 0.5));
	}
	return tmp;
}
U_m = abs(U)
function code(J, K, U_m)
	t_0 = cos(Float64(K / 2.0))
	t_1 = Float64(Float64(-2.0 * J) * t_0)
	t_2 = Float64(t_1 * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
	t_3 = cos(Float64(K * 0.5))
	t_4 = Float64(J * Float64(Float64(-2.0 * t_3) * sqrt(fma(U_m, Float64(U_m / Float64(Float64(J * 2.0) * fma(J, cos(K), J))), 1.0))))
	tmp = 0.0
	if (t_2 <= Float64(-Inf))
		tmp = Float64(-U_m);
	elseif (t_2 <= -3e-95)
		tmp = t_4;
	elseif (t_2 <= 1e-50)
		tmp = Float64(t_1 * sqrt(Float64(1.0 + (Float64(0.5 * Float64(U_m / J)) ^ 2.0))));
	elseif (t_2 <= 5e+301)
		tmp = t_4;
	else
		tmp = Float64(Float64(Float64(-U_m) * t_3) / sqrt(fma(cos(K), 0.5, 0.5)));
	end
	return tmp
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(J * N[(N[(-2.0 * t$95$3), $MachinePrecision] * N[Sqrt[N[(U$95$m * N[(U$95$m / N[(N[(J * 2.0), $MachinePrecision] * N[(J * N[Cos[K], $MachinePrecision] + J), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, (-Infinity)], (-U$95$m), If[LessEqual[t$95$2, -3e-95], t$95$4, If[LessEqual[t$95$2, 1e-50], N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(0.5 * N[(U$95$m / J), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 5e+301], t$95$4, N[(N[((-U$95$m) * t$95$3), $MachinePrecision] / N[Sqrt[N[(N[Cos[K], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]]]]]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
t_1 := \left(-2 \cdot J\right) \cdot t\_0\\
t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
t_3 := \cos \left(K \cdot 0.5\right)\\
t_4 := J \cdot \left(\left(-2 \cdot t\_3\right) \cdot \sqrt{\mathsf{fma}\left(U\_m, \frac{U\_m}{\left(J \cdot 2\right) \cdot \mathsf{fma}\left(J, \cos K, J\right)}, 1\right)}\right)\\
\mathbf{if}\;t\_2 \leq -\infty:\\
\;\;\;\;-U\_m\\

\mathbf{elif}\;t\_2 \leq -3 \cdot 10^{-95}:\\
\;\;\;\;t\_4\\

\mathbf{elif}\;t\_2 \leq 10^{-50}:\\
\;\;\;\;t\_1 \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U\_m}{J}\right)}^{2}}\\

\mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\
\;\;\;\;t\_4\\

\mathbf{else}:\\
\;\;\;\;\frac{\left(-U\_m\right) \cdot t\_3}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 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 5.3%

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

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

        \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
      2. lower-neg.f6450.4

        \[\leadsto \color{blue}{-U} \]
    5. Applied rewrites50.4%

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

    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))))) < -3e-95 or 1.00000000000000001e-50 < (*.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))))) < 5.0000000000000004e301

    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
    3. Applied rewrites94.9%

      \[\leadsto \color{blue}{\left(\sqrt{\mathsf{fma}\left(U, \frac{U}{\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \left(K \cdot 0.5\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J} \]
    4. Step-by-step derivation
      1. lift-fma.f64N/A

        \[\leadsto \left(\sqrt{\color{blue}{U \cdot \frac{U}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)} + 1}} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
    5. Applied rewrites99.7%

      \[\leadsto \left(\sqrt{\color{blue}{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(J, 1, \cos \left(K \cdot 1\right) \cdot \left(J \cdot 1\right)\right)}, \frac{U}{J \cdot 2}, 1\right)}} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J \]
    6. Step-by-step derivation
      1. lift-fma.f64N/A

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

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

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

        \[\leadsto \left(\sqrt{\color{blue}{\frac{U \cdot U}{\mathsf{fma}\left(J, 1, \cos \left(K \cdot 1\right) \cdot \left(J \cdot 1\right)\right) \cdot \left(J \cdot 2\right)}} + 1} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
      5. associate-/l*N/A

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

        \[\leadsto \left(\sqrt{\color{blue}{\mathsf{fma}\left(U, \frac{U}{\mathsf{fma}\left(J, 1, \cos \left(K \cdot 1\right) \cdot \left(J \cdot 1\right)\right) \cdot \left(J \cdot 2\right)}, 1\right)}} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
    7. Applied rewrites94.9%

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

    if -3e-95 < (*.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))))) < 1.00000000000000001e-50

    1. Initial program 99.9%

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

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

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\color{blue}{\left(\frac{1}{2} \cdot \frac{U}{J}\right)}}^{2}} \]
      2. lower-/.f6474.9

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(0.5 \cdot \color{blue}{\frac{U}{J}}\right)}^{2}} \]
    5. Applied rewrites74.9%

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

    if 5.0000000000000004e301 < (*.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 12.5%

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

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

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

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

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

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}} \]
      6. associate-*l/N/A

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}{\cos \left(\frac{K}{2}\right)}}} \]
      7. lift-/.f64N/A

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \frac{\frac{U}{2 \cdot J} \cdot \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}}{\cos \left(\frac{K}{2}\right)}} \]
      8. associate-*r/N/A

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

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      10. lower-/.f64N/A

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
    4. Applied rewrites10.4%

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

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

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

        \[\leadsto \mathsf{neg}\left(\color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)}\right) \]
      3. distribute-rgt-neg-inN/A

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(\mathsf{neg}\left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
      4. mul-1-negN/A

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

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
      6. lower-sqrt.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
      7. lower-/.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
      8. +-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{\color{blue}{\frac{1}{2} \cdot \cos K + \frac{1}{2}}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
      9. lower-fma.f64N/A

        \[\leadsto \sqrt{\frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
      10. lower-cos.f64N/A

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

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
      12. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
      13. mul-1-negN/A

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
      14. lower-neg.f64N/A

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
      15. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}\right) \]
      16. lower-*.f6443.4

        \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}\right) \]
    7. Applied rewrites43.4%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \left(0.5 \cdot K\right)\right)} \]
    8. Step-by-step derivation
      1. Applied rewrites43.5%

        \[\leadsto \color{blue}{\frac{\cos \left(K \cdot 0.5\right) \cdot \left(-U\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}} \]
    9. Recombined 4 regimes into one program.
    10. Final simplification78.3%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -3 \cdot 10^{-95}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \sqrt{\mathsf{fma}\left(U, \frac{U}{\left(J \cdot 2\right) \cdot \mathsf{fma}\left(J, \cos K, J\right)}, 1\right)}\right)\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 10^{-50}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U}{J}\right)}^{2}}\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \sqrt{\mathsf{fma}\left(U, \frac{U}{\left(J \cdot 2\right) \cdot \mathsf{fma}\left(J, \cos K, J\right)}, 1\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \]
    11. Add Preprocessing

    Alternative 3: 78.2% accurate, 0.2× speedup?

    \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ t_2 := \cos \left(K \cdot 0.5\right) \cdot \left(\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(U\_m \cdot 0.25, \frac{U\_m}{J \cdot J}, 1\right)}\right)\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{-130}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 10^{-167}:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;t\_2\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\ \end{array} \end{array} \]
    U_m = (fabs.f64 U)
    (FPCore (J K U_m)
     :precision binary64
     (let* ((t_0 (cos (/ K 2.0)))
            (t_1
             (*
              (* (* -2.0 J) t_0)
              (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0)))))
            (t_2
             (*
              (cos (* K 0.5))
              (* (* -2.0 J) (sqrt (fma (* U_m 0.25) (/ U_m (* J J)) 1.0))))))
       (if (<= t_1 (- INFINITY))
         (- U_m)
         (if (<= t_1 -5e-130)
           t_2
           (if (<= t_1 1e-167)
             (- U_m)
             (if (<= t_1 5e+301) t_2 (* (* -2.0 J) (* (/ U_m J) -0.5))))))))
    U_m = fabs(U);
    double code(double J, double K, double U_m) {
    	double t_0 = cos((K / 2.0));
    	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
    	double t_2 = cos((K * 0.5)) * ((-2.0 * J) * sqrt(fma((U_m * 0.25), (U_m / (J * J)), 1.0)));
    	double tmp;
    	if (t_1 <= -((double) INFINITY)) {
    		tmp = -U_m;
    	} else if (t_1 <= -5e-130) {
    		tmp = t_2;
    	} else if (t_1 <= 1e-167) {
    		tmp = -U_m;
    	} else if (t_1 <= 5e+301) {
    		tmp = t_2;
    	} else {
    		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
    	}
    	return tmp;
    }
    
    U_m = abs(U)
    function code(J, K, U_m)
    	t_0 = cos(Float64(K / 2.0))
    	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
    	t_2 = Float64(cos(Float64(K * 0.5)) * Float64(Float64(-2.0 * J) * sqrt(fma(Float64(U_m * 0.25), Float64(U_m / Float64(J * J)), 1.0))))
    	tmp = 0.0
    	if (t_1 <= Float64(-Inf))
    		tmp = Float64(-U_m);
    	elseif (t_1 <= -5e-130)
    		tmp = t_2;
    	elseif (t_1 <= 1e-167)
    		tmp = Float64(-U_m);
    	elseif (t_1 <= 5e+301)
    		tmp = t_2;
    	else
    		tmp = Float64(Float64(-2.0 * J) * Float64(Float64(U_m / J) * -0.5));
    	end
    	return tmp
    end
    
    U_m = N[Abs[U], $MachinePrecision]
    code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision] * N[(N[(-2.0 * J), $MachinePrecision] * N[Sqrt[N[(N[(U$95$m * 0.25), $MachinePrecision] * N[(U$95$m / N[(J * J), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, -5e-130], t$95$2, If[LessEqual[t$95$1, 1e-167], (-U$95$m), If[LessEqual[t$95$1, 5e+301], t$95$2, N[(N[(-2.0 * J), $MachinePrecision] * N[(N[(U$95$m / J), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]]]]]]]]
    
    \begin{array}{l}
    U_m = \left|U\right|
    
    \\
    \begin{array}{l}
    t_0 := \cos \left(\frac{K}{2}\right)\\
    t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
    t_2 := \cos \left(K \cdot 0.5\right) \cdot \left(\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(U\_m \cdot 0.25, \frac{U\_m}{J \cdot J}, 1\right)}\right)\\
    \mathbf{if}\;t\_1 \leq -\infty:\\
    \;\;\;\;-U\_m\\
    
    \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{-130}:\\
    \;\;\;\;t\_2\\
    
    \mathbf{elif}\;t\_1 \leq 10^{-167}:\\
    \;\;\;\;-U\_m\\
    
    \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+301}:\\
    \;\;\;\;t\_2\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\
    
    
    \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 or -4.9999999999999996e-130 < (*.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))))) < 1e-167

      1. Initial program 31.1%

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

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

          \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
        2. lower-neg.f6446.8

          \[\leadsto \color{blue}{-U} \]
      5. Applied rewrites46.8%

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

      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))))) < -4.9999999999999996e-130 or 1e-167 < (*.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))))) < 5.0000000000000004e301

      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
      3. Taylor expanded in K around 0

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
      4. Step-by-step derivation
        1. lower-sqrt.f64N/A

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

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

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

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
        5. unpow2N/A

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

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
        7. unpow2N/A

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
        8. lower-*.f6476.8

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
      5. Applied rewrites76.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
      6. Step-by-step derivation
        1. lift-*.f64N/A

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

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

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

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \left(\left(-2 \cdot J\right) \cdot \cos \color{blue}{\left(\frac{K}{2}\right)}\right) \]
        5. div-invN/A

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \left(\left(-2 \cdot J\right) \cdot \cos \color{blue}{\left(K \cdot \frac{1}{2}\right)}\right) \]
        6. metadata-evalN/A

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

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \left(\left(-2 \cdot J\right) \cdot \cos \color{blue}{\left(K \cdot \frac{1}{2}\right)}\right) \]
        8. associate-*r*N/A

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

          \[\leadsto \color{blue}{\left(\sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \left(-2 \cdot J\right)\right) \cdot \cos \left(K \cdot \frac{1}{2}\right)} \]
      7. Applied rewrites83.5%

        \[\leadsto \color{blue}{\left(\sqrt{\mathsf{fma}\left(0.25 \cdot U, \frac{U}{J \cdot J}, 1\right)} \cdot \left(J \cdot -2\right)\right) \cdot \cos \left(0.5 \cdot K\right)} \]

      if 5.0000000000000004e301 < (*.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 12.5%

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

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
      4. Step-by-step derivation
        1. lower-sqrt.f64N/A

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

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

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

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
        5. unpow2N/A

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

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
        7. unpow2N/A

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
        8. lower-*.f647.8

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
      5. Applied rewrites7.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
      6. Taylor expanded in U around inf

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{J} + \frac{J}{{U}^{2}}\right)}\right) \]
      7. Step-by-step derivation
        1. Applied rewrites20.0%

          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{J}{U \cdot U} + \frac{0.5}{J}\right)}\right) \]
        2. Step-by-step derivation
          1. lift-*.f64N/A

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

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

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

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

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

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

            \[\leadsto \color{blue}{\left(\cos \left(\frac{K}{2}\right) \cdot \left(U \cdot \left(\frac{J}{U \cdot U} + \frac{\frac{1}{2}}{J}\right)\right)\right) \cdot \left(J \cdot -2\right)} \]
        3. Applied rewrites20.0%

          \[\leadsto \color{blue}{\left(\mathsf{fma}\left(U, \frac{0.5}{J}, \frac{J}{U}\right) \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot -2\right)} \]
        4. Taylor expanded in U around -inf

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

            \[\leadsto \color{blue}{\left(\frac{-1}{2} \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
          2. lower-/.f6430.0

            \[\leadsto \left(-0.5 \cdot \color{blue}{\frac{U}{J}}\right) \cdot \left(J \cdot -2\right) \]
        6. Applied rewrites30.0%

          \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
      8. Recombined 3 regimes into one program.
      9. Final simplification68.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -5 \cdot 10^{-130}:\\ \;\;\;\;\cos \left(K \cdot 0.5\right) \cdot \left(\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(U \cdot 0.25, \frac{U}{J \cdot J}, 1\right)}\right)\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 10^{-167}:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\cos \left(K \cdot 0.5\right) \cdot \left(\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(U \cdot 0.25, \frac{U}{J \cdot J}, 1\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U}{J} \cdot -0.5\right)\\ \end{array} \]
      10. Add Preprocessing

      Alternative 4: 52.5% accurate, 0.2× speedup?

      \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{+187}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{-62}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot U\_m}{J \cdot J}, 1\right)}\\ \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-286}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\ \end{array} \end{array} \]
      U_m = (fabs.f64 U)
      (FPCore (J K U_m)
       :precision binary64
       (let* ((t_0 (cos (/ K 2.0)))
              (t_1
               (*
                (* (* -2.0 J) t_0)
                (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
         (if (<= t_1 (- INFINITY))
           (- U_m)
           (if (<= t_1 -5e+187)
             (* -2.0 J)
             (if (<= t_1 -5e-62)
               (* (* -2.0 J) (sqrt (fma 0.25 (/ (* U_m U_m) (* J J)) 1.0)))
               (if (<= t_1 -1e-286) (- U_m) (* (* -2.0 J) (* (/ U_m J) -0.5))))))))
      U_m = fabs(U);
      double code(double J, double K, double U_m) {
      	double t_0 = cos((K / 2.0));
      	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
      	double tmp;
      	if (t_1 <= -((double) INFINITY)) {
      		tmp = -U_m;
      	} else if (t_1 <= -5e+187) {
      		tmp = -2.0 * J;
      	} else if (t_1 <= -5e-62) {
      		tmp = (-2.0 * J) * sqrt(fma(0.25, ((U_m * U_m) / (J * J)), 1.0));
      	} else if (t_1 <= -1e-286) {
      		tmp = -U_m;
      	} else {
      		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
      	}
      	return tmp;
      }
      
      U_m = abs(U)
      function code(J, K, U_m)
      	t_0 = cos(Float64(K / 2.0))
      	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
      	tmp = 0.0
      	if (t_1 <= Float64(-Inf))
      		tmp = Float64(-U_m);
      	elseif (t_1 <= -5e+187)
      		tmp = Float64(-2.0 * J);
      	elseif (t_1 <= -5e-62)
      		tmp = Float64(Float64(-2.0 * J) * sqrt(fma(0.25, Float64(Float64(U_m * U_m) / Float64(J * J)), 1.0)));
      	elseif (t_1 <= -1e-286)
      		tmp = Float64(-U_m);
      	else
      		tmp = Float64(Float64(-2.0 * J) * Float64(Float64(U_m / J) * -0.5));
      	end
      	return tmp
      end
      
      U_m = N[Abs[U], $MachinePrecision]
      code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, -5e+187], N[(-2.0 * J), $MachinePrecision], If[LessEqual[t$95$1, -5e-62], N[(N[(-2.0 * J), $MachinePrecision] * N[Sqrt[N[(0.25 * N[(N[(U$95$m * U$95$m), $MachinePrecision] / N[(J * J), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, -1e-286], (-U$95$m), N[(N[(-2.0 * J), $MachinePrecision] * N[(N[(U$95$m / J), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]]]]]]]
      
      \begin{array}{l}
      U_m = \left|U\right|
      
      \\
      \begin{array}{l}
      t_0 := \cos \left(\frac{K}{2}\right)\\
      t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
      \mathbf{if}\;t\_1 \leq -\infty:\\
      \;\;\;\;-U\_m\\
      
      \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{+187}:\\
      \;\;\;\;-2 \cdot J\\
      
      \mathbf{elif}\;t\_1 \leq -5 \cdot 10^{-62}:\\
      \;\;\;\;\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot U\_m}{J \cdot J}, 1\right)}\\
      
      \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-286}:\\
      \;\;\;\;-U\_m\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 4 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 or -5.0000000000000002e-62 < (*.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))))) < -1.00000000000000005e-286

        1. Initial program 32.6%

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

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

            \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
          2. lower-neg.f6443.5

            \[\leadsto \color{blue}{-U} \]
        5. Applied rewrites43.5%

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

        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))))) < -5.0000000000000001e187

        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
        3. Taylor expanded in U around 0

          \[\leadsto \color{blue}{-2 \cdot \left(J \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) + \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}} \]
        4. Step-by-step derivation
          1. lower-fma.f64N/A

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

            \[\leadsto \mathsf{fma}\left(-2, \color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
          3. lower-cos.f64N/A

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

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
          5. associate-*r/N/A

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\frac{\frac{-1}{4} \cdot {U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
          6. lower-/.f64N/A

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

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\color{blue}{\frac{-1}{4} \cdot {U}^{2}}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
          8. unpow2N/A

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

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

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{\color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
          11. lower-cos.f64N/A

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{J \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
          12. lower-*.f6478.2

            \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}}\right) \]
        5. Applied rewrites78.2%

          \[\leadsto \color{blue}{\mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \left(0.5 \cdot K\right)}\right)} \]
        6. Taylor expanded in K around 0

          \[\leadsto -2 \cdot J + \color{blue}{\left(\frac{-1}{4} \cdot \frac{{U}^{2}}{J} + {K}^{2} \cdot \left(\frac{-1}{32} \cdot \frac{{U}^{2}}{J} + \frac{1}{4} \cdot J\right)\right)} \]
        7. Step-by-step derivation
          1. Applied rewrites36.0%

            \[\leadsto \mathsf{fma}\left(K, \color{blue}{K \cdot \mathsf{fma}\left(0.25, J, \frac{U \cdot U}{J} \cdot -0.03125\right)}, \mathsf{fma}\left(J, -2, \frac{\left(U \cdot U\right) \cdot -0.25}{J}\right)\right) \]
          2. Taylor expanded in J around inf

            \[\leadsto J \cdot \left(\frac{1}{4} \cdot {K}^{2} - \color{blue}{2}\right) \]
          3. Step-by-step derivation
            1. Applied rewrites39.0%

              \[\leadsto J \cdot \mathsf{fma}\left(0.25, \color{blue}{K \cdot K}, -2\right) \]
            2. Taylor expanded in K around 0

              \[\leadsto -2 \cdot J \]
            3. Step-by-step derivation
              1. Applied rewrites41.7%

                \[\leadsto J \cdot -2 \]

              if -5.0000000000000001e187 < (*.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))))) < -5.0000000000000002e-62

              1. Initial program 100.0%

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

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

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

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

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

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

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

                  \[\leadsto \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \cdot \left(-2 \cdot J\right) \]
                8. unpow2N/A

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

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

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

                  \[\leadsto \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \cdot \left(-2 \cdot J\right) \]
                12. lower-*.f6451.2

                  \[\leadsto \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \color{blue}{\left(-2 \cdot J\right)} \]
              5. Applied rewrites51.2%

                \[\leadsto \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)} \cdot \left(-2 \cdot J\right)} \]

              if -1.00000000000000005e-286 < (*.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 73.4%

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

                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
              4. Step-by-step derivation
                1. lower-sqrt.f64N/A

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

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

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

                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                5. unpow2N/A

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

                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                7. unpow2N/A

                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                8. lower-*.f6449.3

                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
              5. Applied rewrites49.3%

                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
              6. Taylor expanded in U around inf

                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{J} + \frac{J}{{U}^{2}}\right)}\right) \]
              7. Step-by-step derivation
                1. Applied rewrites13.7%

                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{J}{U \cdot U} + \frac{0.5}{J}\right)}\right) \]
                2. Step-by-step derivation
                  1. lift-*.f64N/A

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

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

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

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

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

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

                    \[\leadsto \color{blue}{\left(\cos \left(\frac{K}{2}\right) \cdot \left(U \cdot \left(\frac{J}{U \cdot U} + \frac{\frac{1}{2}}{J}\right)\right)\right) \cdot \left(J \cdot -2\right)} \]
                3. Applied rewrites15.4%

                  \[\leadsto \color{blue}{\left(\mathsf{fma}\left(U, \frac{0.5}{J}, \frac{J}{U}\right) \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot -2\right)} \]
                4. Taylor expanded in U around -inf

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

                    \[\leadsto \color{blue}{\left(\frac{-1}{2} \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                  2. lower-/.f6421.2

                    \[\leadsto \left(-0.5 \cdot \color{blue}{\frac{U}{J}}\right) \cdot \left(J \cdot -2\right) \]
                6. Applied rewrites21.2%

                  \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
              8. Recombined 4 regimes into one program.
              9. Final simplification32.4%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -5 \cdot 10^{+187}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -5 \cdot 10^{-62}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -1 \cdot 10^{-286}:\\ \;\;\;\;-U\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U}{J} \cdot -0.5\right)\\ \end{array} \]
              10. Add Preprocessing

              Alternative 5: 49.8% accurate, 0.3× speedup?

              \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-6}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-286}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\ \end{array} \end{array} \]
              U_m = (fabs.f64 U)
              (FPCore (J K U_m)
               :precision binary64
               (let* ((t_0 (cos (/ K 2.0)))
                      (t_1
                       (*
                        (* (* -2.0 J) t_0)
                        (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
                 (if (<= t_1 (- INFINITY))
                   (- U_m)
                   (if (<= t_1 -1e-6)
                     (* -2.0 J)
                     (if (<= t_1 -1e-286) (- U_m) (* (* -2.0 J) (* (/ U_m J) -0.5)))))))
              U_m = fabs(U);
              double code(double J, double K, double U_m) {
              	double t_0 = cos((K / 2.0));
              	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
              	double tmp;
              	if (t_1 <= -((double) INFINITY)) {
              		tmp = -U_m;
              	} else if (t_1 <= -1e-6) {
              		tmp = -2.0 * J;
              	} else if (t_1 <= -1e-286) {
              		tmp = -U_m;
              	} else {
              		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
              	}
              	return tmp;
              }
              
              U_m = Math.abs(U);
              public static double code(double J, double K, double U_m) {
              	double t_0 = Math.cos((K / 2.0));
              	double t_1 = ((-2.0 * J) * t_0) * Math.sqrt((1.0 + Math.pow((U_m / (t_0 * (J * 2.0))), 2.0)));
              	double tmp;
              	if (t_1 <= -Double.POSITIVE_INFINITY) {
              		tmp = -U_m;
              	} else if (t_1 <= -1e-6) {
              		tmp = -2.0 * J;
              	} else if (t_1 <= -1e-286) {
              		tmp = -U_m;
              	} else {
              		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
              	}
              	return tmp;
              }
              
              U_m = math.fabs(U)
              def code(J, K, U_m):
              	t_0 = math.cos((K / 2.0))
              	t_1 = ((-2.0 * J) * t_0) * math.sqrt((1.0 + math.pow((U_m / (t_0 * (J * 2.0))), 2.0)))
              	tmp = 0
              	if t_1 <= -math.inf:
              		tmp = -U_m
              	elif t_1 <= -1e-6:
              		tmp = -2.0 * J
              	elif t_1 <= -1e-286:
              		tmp = -U_m
              	else:
              		tmp = (-2.0 * J) * ((U_m / J) * -0.5)
              	return tmp
              
              U_m = abs(U)
              function code(J, K, U_m)
              	t_0 = cos(Float64(K / 2.0))
              	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
              	tmp = 0.0
              	if (t_1 <= Float64(-Inf))
              		tmp = Float64(-U_m);
              	elseif (t_1 <= -1e-6)
              		tmp = Float64(-2.0 * J);
              	elseif (t_1 <= -1e-286)
              		tmp = Float64(-U_m);
              	else
              		tmp = Float64(Float64(-2.0 * J) * Float64(Float64(U_m / J) * -0.5));
              	end
              	return tmp
              end
              
              U_m = abs(U);
              function tmp_2 = code(J, K, U_m)
              	t_0 = cos((K / 2.0));
              	t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + ((U_m / (t_0 * (J * 2.0))) ^ 2.0)));
              	tmp = 0.0;
              	if (t_1 <= -Inf)
              		tmp = -U_m;
              	elseif (t_1 <= -1e-6)
              		tmp = -2.0 * J;
              	elseif (t_1 <= -1e-286)
              		tmp = -U_m;
              	else
              		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
              	end
              	tmp_2 = tmp;
              end
              
              U_m = N[Abs[U], $MachinePrecision]
              code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, -1e-6], N[(-2.0 * J), $MachinePrecision], If[LessEqual[t$95$1, -1e-286], (-U$95$m), N[(N[(-2.0 * J), $MachinePrecision] * N[(N[(U$95$m / J), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]]]]]]
              
              \begin{array}{l}
              U_m = \left|U\right|
              
              \\
              \begin{array}{l}
              t_0 := \cos \left(\frac{K}{2}\right)\\
              t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
              \mathbf{if}\;t\_1 \leq -\infty:\\
              \;\;\;\;-U\_m\\
              
              \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-6}:\\
              \;\;\;\;-2 \cdot J\\
              
              \mathbf{elif}\;t\_1 \leq -1 \cdot 10^{-286}:\\
              \;\;\;\;-U\_m\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\
              
              
              \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 or -9.99999999999999955e-7 < (*.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))))) < -1.00000000000000005e-286

                1. Initial program 43.8%

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

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

                    \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                  2. lower-neg.f6438.5

                    \[\leadsto \color{blue}{-U} \]
                5. Applied rewrites38.5%

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

                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))))) < -9.99999999999999955e-7

                1. Initial program 99.9%

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

                  \[\leadsto \color{blue}{-2 \cdot \left(J \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) + \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}} \]
                4. Step-by-step derivation
                  1. lower-fma.f64N/A

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

                    \[\leadsto \mathsf{fma}\left(-2, \color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                  3. lower-cos.f64N/A

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

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                  5. associate-*r/N/A

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\frac{\frac{-1}{4} \cdot {U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                  6. lower-/.f64N/A

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

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\color{blue}{\frac{-1}{4} \cdot {U}^{2}}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                  8. unpow2N/A

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

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

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{\color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                  11. lower-cos.f64N/A

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{J \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                  12. lower-*.f6483.6

                    \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}}\right) \]
                5. Applied rewrites83.6%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \left(0.5 \cdot K\right)}\right)} \]
                6. Taylor expanded in K around 0

                  \[\leadsto -2 \cdot J + \color{blue}{\left(\frac{-1}{4} \cdot \frac{{U}^{2}}{J} + {K}^{2} \cdot \left(\frac{-1}{32} \cdot \frac{{U}^{2}}{J} + \frac{1}{4} \cdot J\right)\right)} \]
                7. Step-by-step derivation
                  1. Applied rewrites40.2%

                    \[\leadsto \mathsf{fma}\left(K, \color{blue}{K \cdot \mathsf{fma}\left(0.25, J, \frac{U \cdot U}{J} \cdot -0.03125\right)}, \mathsf{fma}\left(J, -2, \frac{\left(U \cdot U\right) \cdot -0.25}{J}\right)\right) \]
                  2. Taylor expanded in J around inf

                    \[\leadsto J \cdot \left(\frac{1}{4} \cdot {K}^{2} - \color{blue}{2}\right) \]
                  3. Step-by-step derivation
                    1. Applied rewrites41.7%

                      \[\leadsto J \cdot \mathsf{fma}\left(0.25, \color{blue}{K \cdot K}, -2\right) \]
                    2. Taylor expanded in K around 0

                      \[\leadsto -2 \cdot J \]
                    3. Step-by-step derivation
                      1. Applied rewrites45.1%

                        \[\leadsto J \cdot -2 \]

                      if -1.00000000000000005e-286 < (*.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 73.4%

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

                        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
                      4. Step-by-step derivation
                        1. lower-sqrt.f64N/A

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

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

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

                          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                        5. unpow2N/A

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

                          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                        7. unpow2N/A

                          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                        8. lower-*.f6449.3

                          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                      5. Applied rewrites49.3%

                        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
                      6. Taylor expanded in U around inf

                        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{J} + \frac{J}{{U}^{2}}\right)}\right) \]
                      7. Step-by-step derivation
                        1. Applied rewrites13.7%

                          \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{J}{U \cdot U} + \frac{0.5}{J}\right)}\right) \]
                        2. Step-by-step derivation
                          1. lift-*.f64N/A

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

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

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

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

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

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

                            \[\leadsto \color{blue}{\left(\cos \left(\frac{K}{2}\right) \cdot \left(U \cdot \left(\frac{J}{U \cdot U} + \frac{\frac{1}{2}}{J}\right)\right)\right) \cdot \left(J \cdot -2\right)} \]
                        3. Applied rewrites15.4%

                          \[\leadsto \color{blue}{\left(\mathsf{fma}\left(U, \frac{0.5}{J}, \frac{J}{U}\right) \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot -2\right)} \]
                        4. Taylor expanded in U around -inf

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

                            \[\leadsto \color{blue}{\left(\frac{-1}{2} \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                          2. lower-/.f6421.2

                            \[\leadsto \left(-0.5 \cdot \color{blue}{\frac{U}{J}}\right) \cdot \left(J \cdot -2\right) \]
                        6. Applied rewrites21.2%

                          \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                      8. Recombined 3 regimes into one program.
                      9. Final simplification30.7%

                        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -1 \cdot 10^{-6}:\\ \;\;\;\;-2 \cdot J\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -1 \cdot 10^{-286}:\\ \;\;\;\;-U\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U}{J} \cdot -0.5\right)\\ \end{array} \]
                      10. Add Preprocessing

                      Alternative 6: 99.4% accurate, 0.4× speedup?

                      \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(K \cdot 0.5\right)\\ t_1 := \cos \left(\frac{K}{2}\right)\\ t_2 := \left(\left(-2 \cdot J\right) \cdot t\_1\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_1 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_2 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;J \cdot \left(\sqrt{\mathsf{fma}\left(\frac{U\_m}{\mathsf{fma}\left(J, 1, J \cdot \cos K\right)}, \frac{U\_m}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot t\_0\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {t\_0}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\ \end{array} \end{array} \]
                      U_m = (fabs.f64 U)
                      (FPCore (J K U_m)
                       :precision binary64
                       (let* ((t_0 (cos (* K 0.5)))
                              (t_1 (cos (/ K 2.0)))
                              (t_2
                               (*
                                (* (* -2.0 J) t_1)
                                (sqrt (+ 1.0 (pow (/ U_m (* t_1 (* J 2.0))) 2.0))))))
                         (if (<= t_2 (- INFINITY))
                           (- U_m)
                           (if (<= t_2 5e+305)
                             (*
                              J
                              (*
                               (sqrt (fma (/ U_m (fma J 1.0 (* J (cos K)))) (/ U_m (* J 2.0)) 1.0))
                               (* -2.0 t_0)))
                             (*
                              (- U_m)
                              (fma -2.0 (* (pow t_0 2.0) (/ (* J J) (* U_m U_m))) -1.0))))))
                      U_m = fabs(U);
                      double code(double J, double K, double U_m) {
                      	double t_0 = cos((K * 0.5));
                      	double t_1 = cos((K / 2.0));
                      	double t_2 = ((-2.0 * J) * t_1) * sqrt((1.0 + pow((U_m / (t_1 * (J * 2.0))), 2.0)));
                      	double tmp;
                      	if (t_2 <= -((double) INFINITY)) {
                      		tmp = -U_m;
                      	} else if (t_2 <= 5e+305) {
                      		tmp = J * (sqrt(fma((U_m / fma(J, 1.0, (J * cos(K)))), (U_m / (J * 2.0)), 1.0)) * (-2.0 * t_0));
                      	} else {
                      		tmp = -U_m * fma(-2.0, (pow(t_0, 2.0) * ((J * J) / (U_m * U_m))), -1.0);
                      	}
                      	return tmp;
                      }
                      
                      U_m = abs(U)
                      function code(J, K, U_m)
                      	t_0 = cos(Float64(K * 0.5))
                      	t_1 = cos(Float64(K / 2.0))
                      	t_2 = Float64(Float64(Float64(-2.0 * J) * t_1) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_1 * Float64(J * 2.0))) ^ 2.0))))
                      	tmp = 0.0
                      	if (t_2 <= Float64(-Inf))
                      		tmp = Float64(-U_m);
                      	elseif (t_2 <= 5e+305)
                      		tmp = Float64(J * Float64(sqrt(fma(Float64(U_m / fma(J, 1.0, Float64(J * cos(K)))), Float64(U_m / Float64(J * 2.0)), 1.0)) * Float64(-2.0 * t_0)));
                      	else
                      		tmp = Float64(Float64(-U_m) * fma(-2.0, Float64((t_0 ^ 2.0) * Float64(Float64(J * J) / Float64(U_m * U_m))), -1.0));
                      	end
                      	return tmp
                      end
                      
                      U_m = N[Abs[U], $MachinePrecision]
                      code[J_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(-2.0 * J), $MachinePrecision] * t$95$1), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$1 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, (-Infinity)], (-U$95$m), If[LessEqual[t$95$2, 5e+305], N[(J * N[(N[Sqrt[N[(N[(U$95$m / N[(J * 1.0 + N[(J * N[Cos[K], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(U$95$m / N[(J * 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision] * N[(-2.0 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[((-U$95$m) * N[(-2.0 * N[(N[Power[t$95$0, 2.0], $MachinePrecision] * N[(N[(J * J), $MachinePrecision] / N[(U$95$m * U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]]]]]]
                      
                      \begin{array}{l}
                      U_m = \left|U\right|
                      
                      \\
                      \begin{array}{l}
                      t_0 := \cos \left(K \cdot 0.5\right)\\
                      t_1 := \cos \left(\frac{K}{2}\right)\\
                      t_2 := \left(\left(-2 \cdot J\right) \cdot t\_1\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_1 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                      \mathbf{if}\;t\_2 \leq -\infty:\\
                      \;\;\;\;-U\_m\\
                      
                      \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+305}:\\
                      \;\;\;\;J \cdot \left(\sqrt{\mathsf{fma}\left(\frac{U\_m}{\mathsf{fma}\left(J, 1, J \cdot \cos K\right)}, \frac{U\_m}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot t\_0\right)\right)\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {t\_0}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\
                      
                      
                      \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 5.3%

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

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

                            \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                          2. lower-neg.f6450.4

                            \[\leadsto \color{blue}{-U} \]
                        5. Applied rewrites50.4%

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

                        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))))) < 5.00000000000000009e305

                        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
                        3. Applied rewrites83.8%

                          \[\leadsto \color{blue}{\left(\sqrt{\mathsf{fma}\left(U, \frac{U}{\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \left(K \cdot 0.5\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J} \]
                        4. Step-by-step derivation
                          1. lift-fma.f64N/A

                            \[\leadsto \left(\sqrt{\color{blue}{U \cdot \frac{U}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)} + 1}} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
                        5. Applied rewrites99.7%

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

                        if 5.00000000000000009e305 < (*.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 5.8%

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

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

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

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

                            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} - 1\right) \]
                          4. lower-neg.f64N/A

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
                          6. metadata-evalN/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \color{blue}{-1}\right) \]
                          7. lower-fma.f64N/A

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

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

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
                          11. lower-pow.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
                          12. lower-cos.f64N/A

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
                          14. lower-/.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \color{blue}{\frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
                          15. unpow2N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
                          16. lower-*.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
                          17. unpow2N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
                          18. lower-*.f6446.5

                            \[\leadsto \left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
                        5. Applied rewrites46.5%

                          \[\leadsto \color{blue}{\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)} \]
                      3. Recombined 3 regimes into one program.
                      4. Final simplification85.4%

                        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+305}:\\ \;\;\;\;J \cdot \left(\sqrt{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(J, 1, J \cdot \cos K\right)}, \frac{U}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(K \cdot 0.5\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)\\ \end{array} \]
                      5. Add Preprocessing

                      Alternative 7: 99.5% accurate, 0.4× speedup?

                      \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ t_2 := \cos \left(K \cdot 0.5\right)\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot t\_2\right) \cdot \sqrt{\mathsf{fma}\left(\frac{U\_m}{\mathsf{fma}\left(\cos K, J, J\right)}, \frac{U\_m}{J \cdot 2}, 1\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {t\_2}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\ \end{array} \end{array} \]
                      U_m = (fabs.f64 U)
                      (FPCore (J K U_m)
                       :precision binary64
                       (let* ((t_0 (cos (/ K 2.0)))
                              (t_1
                               (*
                                (* (* -2.0 J) t_0)
                                (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0)))))
                              (t_2 (cos (* K 0.5))))
                         (if (<= t_1 (- INFINITY))
                           (- U_m)
                           (if (<= t_1 5e+305)
                             (*
                              J
                              (*
                               (* -2.0 t_2)
                               (sqrt (fma (/ U_m (fma (cos K) J J)) (/ U_m (* J 2.0)) 1.0))))
                             (*
                              (- U_m)
                              (fma -2.0 (* (pow t_2 2.0) (/ (* J J) (* U_m U_m))) -1.0))))))
                      U_m = fabs(U);
                      double code(double J, double K, double U_m) {
                      	double t_0 = cos((K / 2.0));
                      	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                      	double t_2 = cos((K * 0.5));
                      	double tmp;
                      	if (t_1 <= -((double) INFINITY)) {
                      		tmp = -U_m;
                      	} else if (t_1 <= 5e+305) {
                      		tmp = J * ((-2.0 * t_2) * sqrt(fma((U_m / fma(cos(K), J, J)), (U_m / (J * 2.0)), 1.0)));
                      	} else {
                      		tmp = -U_m * fma(-2.0, (pow(t_2, 2.0) * ((J * J) / (U_m * U_m))), -1.0);
                      	}
                      	return tmp;
                      }
                      
                      U_m = abs(U)
                      function code(J, K, U_m)
                      	t_0 = cos(Float64(K / 2.0))
                      	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
                      	t_2 = cos(Float64(K * 0.5))
                      	tmp = 0.0
                      	if (t_1 <= Float64(-Inf))
                      		tmp = Float64(-U_m);
                      	elseif (t_1 <= 5e+305)
                      		tmp = Float64(J * Float64(Float64(-2.0 * t_2) * sqrt(fma(Float64(U_m / fma(cos(K), J, J)), Float64(U_m / Float64(J * 2.0)), 1.0))));
                      	else
                      		tmp = Float64(Float64(-U_m) * fma(-2.0, Float64((t_2 ^ 2.0) * Float64(Float64(J * J) / Float64(U_m * U_m))), -1.0));
                      	end
                      	return tmp
                      end
                      
                      U_m = N[Abs[U], $MachinePrecision]
                      code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, 5e+305], N[(J * N[(N[(-2.0 * t$95$2), $MachinePrecision] * N[Sqrt[N[(N[(U$95$m / N[(N[Cos[K], $MachinePrecision] * J + J), $MachinePrecision]), $MachinePrecision] * N[(U$95$m / N[(J * 2.0), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[((-U$95$m) * N[(-2.0 * N[(N[Power[t$95$2, 2.0], $MachinePrecision] * N[(N[(J * J), $MachinePrecision] / N[(U$95$m * U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]]]]]]
                      
                      \begin{array}{l}
                      U_m = \left|U\right|
                      
                      \\
                      \begin{array}{l}
                      t_0 := \cos \left(\frac{K}{2}\right)\\
                      t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                      t_2 := \cos \left(K \cdot 0.5\right)\\
                      \mathbf{if}\;t\_1 \leq -\infty:\\
                      \;\;\;\;-U\_m\\
                      
                      \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+305}:\\
                      \;\;\;\;J \cdot \left(\left(-2 \cdot t\_2\right) \cdot \sqrt{\mathsf{fma}\left(\frac{U\_m}{\mathsf{fma}\left(\cos K, J, J\right)}, \frac{U\_m}{J \cdot 2}, 1\right)}\right)\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\left(-U\_m\right) \cdot \mathsf{fma}\left(-2, {t\_2}^{2} \cdot \frac{J \cdot J}{U\_m \cdot U\_m}, -1\right)\\
                      
                      
                      \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 5.3%

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

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

                            \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                          2. lower-neg.f6450.4

                            \[\leadsto \color{blue}{-U} \]
                        5. Applied rewrites50.4%

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

                        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))))) < 5.00000000000000009e305

                        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
                        3. Applied rewrites83.8%

                          \[\leadsto \color{blue}{\left(\sqrt{\mathsf{fma}\left(U, \frac{U}{\left(0.5 + 0.5 \cdot \cos \left(2 \cdot \left(K \cdot 0.5\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J} \]
                        4. Step-by-step derivation
                          1. lift-fma.f64N/A

                            \[\leadsto \left(\sqrt{\color{blue}{U \cdot \frac{U}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot \left(\left(J \cdot 2\right) \cdot \left(J \cdot 2\right)\right)} + 1}} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
                        5. Applied rewrites99.7%

                          \[\leadsto \left(\sqrt{\color{blue}{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(J, 1, \cos \left(K \cdot 1\right) \cdot \left(J \cdot 1\right)\right)}, \frac{U}{J \cdot 2}, 1\right)}} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J \]
                        6. Step-by-step derivation
                          1. lift-fma.f64N/A

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

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

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

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

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

                            \[\leadsto \left(\sqrt{\mathsf{fma}\left(\frac{U}{\cos \left(K \cdot 1\right) \cdot \color{blue}{J} + J}, \frac{U}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
                          7. lower-fma.f6499.7

                            \[\leadsto \left(\sqrt{\mathsf{fma}\left(\frac{U}{\color{blue}{\mathsf{fma}\left(\cos \left(K \cdot 1\right), J, J\right)}}, \frac{U}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J \]
                          8. lift-*.f64N/A

                            \[\leadsto \left(\sqrt{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(\cos \color{blue}{\left(K \cdot 1\right)}, J, J\right)}, \frac{U}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot \frac{1}{2}\right)\right)\right) \cdot J \]
                          9. *-rgt-identity99.7

                            \[\leadsto \left(\sqrt{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(\cos \color{blue}{K}, J, J\right)}, \frac{U}{J \cdot 2}, 1\right)} \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\right) \cdot J \]
                        7. Applied rewrites99.7%

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

                        if 5.00000000000000009e305 < (*.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 5.8%

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

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

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

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

                            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} - 1\right) \]
                          4. lower-neg.f64N/A

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
                          6. metadata-evalN/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \left(-2 \cdot \frac{{J}^{2} \cdot {\cos \left(\frac{1}{2} \cdot K\right)}^{2}}{{U}^{2}} + \color{blue}{-1}\right) \]
                          7. lower-fma.f64N/A

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

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

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
                          11. lower-pow.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, \color{blue}{{\cos \left(\frac{1}{2} \cdot K\right)}^{2}} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
                          12. lower-cos.f64N/A

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

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}}^{2} \cdot \frac{{J}^{2}}{{U}^{2}}, -1\right) \]
                          14. lower-/.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \color{blue}{\frac{{J}^{2}}{{U}^{2}}}, -1\right) \]
                          15. unpow2N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
                          16. lower-*.f64N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{\color{blue}{J \cdot J}}{{U}^{2}}, -1\right) \]
                          17. unpow2N/A

                            \[\leadsto \left(\mathsf{neg}\left(U\right)\right) \cdot \mathsf{fma}\left(-2, {\cos \left(\frac{1}{2} \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
                          18. lower-*.f6446.5

                            \[\leadsto \left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{\color{blue}{U \cdot U}}, -1\right) \]
                        5. Applied rewrites46.5%

                          \[\leadsto \color{blue}{\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(0.5 \cdot K\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)} \]
                      3. Recombined 3 regimes into one program.
                      4. Final simplification85.4%

                        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+305}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{U}{\mathsf{fma}\left(\cos K, J, J\right)}, \frac{U}{J \cdot 2}, 1\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-U\right) \cdot \mathsf{fma}\left(-2, {\cos \left(K \cdot 0.5\right)}^{2} \cdot \frac{J \cdot J}{U \cdot U}, -1\right)\\ \end{array} \]
                      5. Add Preprocessing

                      Alternative 8: 79.8% accurate, 0.4× speedup?

                      \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(-2 \cdot J\right) \cdot t\_0\\ t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_2 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;t\_1 \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U\_m}{J}\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\_m\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \end{array} \]
                      U_m = (fabs.f64 U)
                      (FPCore (J K U_m)
                       :precision binary64
                       (let* ((t_0 (cos (/ K 2.0)))
                              (t_1 (* (* -2.0 J) t_0))
                              (t_2 (* t_1 (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
                         (if (<= t_2 (- INFINITY))
                           (- U_m)
                           (if (<= t_2 5e+301)
                             (* t_1 (sqrt (+ 1.0 (pow (* 0.5 (/ U_m J)) 2.0))))
                             (/ (* (- U_m) (cos (* K 0.5))) (sqrt (fma (cos K) 0.5 0.5)))))))
                      U_m = fabs(U);
                      double code(double J, double K, double U_m) {
                      	double t_0 = cos((K / 2.0));
                      	double t_1 = (-2.0 * J) * t_0;
                      	double t_2 = t_1 * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                      	double tmp;
                      	if (t_2 <= -((double) INFINITY)) {
                      		tmp = -U_m;
                      	} else if (t_2 <= 5e+301) {
                      		tmp = t_1 * sqrt((1.0 + pow((0.5 * (U_m / J)), 2.0)));
                      	} else {
                      		tmp = (-U_m * cos((K * 0.5))) / sqrt(fma(cos(K), 0.5, 0.5));
                      	}
                      	return tmp;
                      }
                      
                      U_m = abs(U)
                      function code(J, K, U_m)
                      	t_0 = cos(Float64(K / 2.0))
                      	t_1 = Float64(Float64(-2.0 * J) * t_0)
                      	t_2 = Float64(t_1 * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
                      	tmp = 0.0
                      	if (t_2 <= Float64(-Inf))
                      		tmp = Float64(-U_m);
                      	elseif (t_2 <= 5e+301)
                      		tmp = Float64(t_1 * sqrt(Float64(1.0 + (Float64(0.5 * Float64(U_m / J)) ^ 2.0))));
                      	else
                      		tmp = Float64(Float64(Float64(-U_m) * cos(Float64(K * 0.5))) / sqrt(fma(cos(K), 0.5, 0.5)));
                      	end
                      	return tmp
                      end
                      
                      U_m = N[Abs[U], $MachinePrecision]
                      code[J_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, (-Infinity)], (-U$95$m), If[LessEqual[t$95$2, 5e+301], N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(0.5 * N[(U$95$m / J), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[((-U$95$m) * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(N[Cos[K], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]]
                      
                      \begin{array}{l}
                      U_m = \left|U\right|
                      
                      \\
                      \begin{array}{l}
                      t_0 := \cos \left(\frac{K}{2}\right)\\
                      t_1 := \left(-2 \cdot J\right) \cdot t\_0\\
                      t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                      \mathbf{if}\;t\_2 \leq -\infty:\\
                      \;\;\;\;-U\_m\\
                      
                      \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\
                      \;\;\;\;t\_1 \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U\_m}{J}\right)}^{2}}\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\frac{\left(-U\_m\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\
                      
                      
                      \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 5.3%

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

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

                            \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                          2. lower-neg.f6450.4

                            \[\leadsto \color{blue}{-U} \]
                        5. Applied rewrites50.4%

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

                        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))))) < 5.0000000000000004e301

                        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
                        3. Taylor expanded in K around 0

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

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\color{blue}{\left(\frac{1}{2} \cdot \frac{U}{J}\right)}}^{2}} \]
                          2. lower-/.f6486.9

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(0.5 \cdot \color{blue}{\frac{U}{J}}\right)}^{2}} \]
                        5. Applied rewrites86.9%

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

                        if 5.0000000000000004e301 < (*.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 12.5%

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

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

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

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

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

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}} \]
                          6. associate-*l/N/A

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}{\cos \left(\frac{K}{2}\right)}}} \]
                          7. lift-/.f64N/A

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \frac{\frac{U}{2 \cdot J} \cdot \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}}{\cos \left(\frac{K}{2}\right)}} \]
                          8. associate-*r/N/A

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

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
                          10. lower-/.f64N/A

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
                        4. Applied rewrites10.4%

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

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

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

                            \[\leadsto \mathsf{neg}\left(\color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)}\right) \]
                          3. distribute-rgt-neg-inN/A

                            \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(\mathsf{neg}\left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
                          4. mul-1-negN/A

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

                            \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
                          6. lower-sqrt.f64N/A

                            \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                          7. lower-/.f64N/A

                            \[\leadsto \sqrt{\color{blue}{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                          8. +-commutativeN/A

                            \[\leadsto \sqrt{\frac{1}{\color{blue}{\frac{1}{2} \cdot \cos K + \frac{1}{2}}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                          9. lower-fma.f64N/A

                            \[\leadsto \sqrt{\frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                          10. lower-cos.f64N/A

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

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
                          12. lower-*.f64N/A

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
                          13. mul-1-negN/A

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
                          14. lower-neg.f64N/A

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
                          15. lower-cos.f64N/A

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                          16. lower-*.f6443.4

                            \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}\right) \]
                        7. Applied rewrites43.4%

                          \[\leadsto \color{blue}{\sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \left(0.5 \cdot K\right)\right)} \]
                        8. Step-by-step derivation
                          1. Applied rewrites43.5%

                            \[\leadsto \color{blue}{\frac{\cos \left(K \cdot 0.5\right) \cdot \left(-U\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}} \]
                        9. Recombined 3 regimes into one program.
                        10. Final simplification75.2%

                          \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(0.5 \cdot \frac{U}{J}\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \]
                        11. Add Preprocessing

                        Alternative 9: 78.4% accurate, 0.4× speedup?

                        \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(-2 \cdot J\right) \cdot t\_0\\ t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_2 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;t\_1 \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot \frac{U\_m}{J}}{J}, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\_m\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \end{array} \]
                        U_m = (fabs.f64 U)
                        (FPCore (J K U_m)
                         :precision binary64
                         (let* ((t_0 (cos (/ K 2.0)))
                                (t_1 (* (* -2.0 J) t_0))
                                (t_2 (* t_1 (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
                           (if (<= t_2 (- INFINITY))
                             (- U_m)
                             (if (<= t_2 5e+301)
                               (* t_1 (sqrt (fma 0.25 (/ (* U_m (/ U_m J)) J) 1.0)))
                               (/ (* (- U_m) (cos (* K 0.5))) (sqrt (fma (cos K) 0.5 0.5)))))))
                        U_m = fabs(U);
                        double code(double J, double K, double U_m) {
                        	double t_0 = cos((K / 2.0));
                        	double t_1 = (-2.0 * J) * t_0;
                        	double t_2 = t_1 * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                        	double tmp;
                        	if (t_2 <= -((double) INFINITY)) {
                        		tmp = -U_m;
                        	} else if (t_2 <= 5e+301) {
                        		tmp = t_1 * sqrt(fma(0.25, ((U_m * (U_m / J)) / J), 1.0));
                        	} else {
                        		tmp = (-U_m * cos((K * 0.5))) / sqrt(fma(cos(K), 0.5, 0.5));
                        	}
                        	return tmp;
                        }
                        
                        U_m = abs(U)
                        function code(J, K, U_m)
                        	t_0 = cos(Float64(K / 2.0))
                        	t_1 = Float64(Float64(-2.0 * J) * t_0)
                        	t_2 = Float64(t_1 * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
                        	tmp = 0.0
                        	if (t_2 <= Float64(-Inf))
                        		tmp = Float64(-U_m);
                        	elseif (t_2 <= 5e+301)
                        		tmp = Float64(t_1 * sqrt(fma(0.25, Float64(Float64(U_m * Float64(U_m / J)) / J), 1.0)));
                        	else
                        		tmp = Float64(Float64(Float64(-U_m) * cos(Float64(K * 0.5))) / sqrt(fma(cos(K), 0.5, 0.5)));
                        	end
                        	return tmp
                        end
                        
                        U_m = N[Abs[U], $MachinePrecision]
                        code[J_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, (-Infinity)], (-U$95$m), If[LessEqual[t$95$2, 5e+301], N[(t$95$1 * N[Sqrt[N[(0.25 * N[(N[(U$95$m * N[(U$95$m / J), $MachinePrecision]), $MachinePrecision] / J), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[((-U$95$m) * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(N[Cos[K], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]]
                        
                        \begin{array}{l}
                        U_m = \left|U\right|
                        
                        \\
                        \begin{array}{l}
                        t_0 := \cos \left(\frac{K}{2}\right)\\
                        t_1 := \left(-2 \cdot J\right) \cdot t\_0\\
                        t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                        \mathbf{if}\;t\_2 \leq -\infty:\\
                        \;\;\;\;-U\_m\\
                        
                        \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\
                        \;\;\;\;t\_1 \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot \frac{U\_m}{J}}{J}, 1\right)}\\
                        
                        \mathbf{else}:\\
                        \;\;\;\;\frac{\left(-U\_m\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\
                        
                        
                        \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 5.3%

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

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

                              \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                            2. lower-neg.f6450.4

                              \[\leadsto \color{blue}{-U} \]
                          5. Applied rewrites50.4%

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

                          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))))) < 5.0000000000000004e301

                          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
                          3. Taylor expanded in K around 0

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
                          4. Step-by-step derivation
                            1. lower-sqrt.f64N/A

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

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

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

                              \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                            5. unpow2N/A

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

                              \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                            7. unpow2N/A

                              \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                            8. lower-*.f6471.8

                              \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                          5. Applied rewrites71.8%

                            \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
                          6. Step-by-step derivation
                            1. Applied rewrites86.2%

                              \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{\frac{U}{J} \cdot U}{J}, 1\right)} \]

                            if 5.0000000000000004e301 < (*.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 12.5%

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

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

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

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

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

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}} \]
                              6. associate-*l/N/A

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}{\cos \left(\frac{K}{2}\right)}}} \]
                              7. lift-/.f64N/A

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \frac{\frac{U}{2 \cdot J} \cdot \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}}{\cos \left(\frac{K}{2}\right)}} \]
                              8. associate-*r/N/A

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

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
                              10. lower-/.f64N/A

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{\frac{U}{2 \cdot J} \cdot U}{\left(\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
                            4. Applied rewrites10.4%

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

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

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

                                \[\leadsto \mathsf{neg}\left(\color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)}\right) \]
                              3. distribute-rgt-neg-inN/A

                                \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(\mathsf{neg}\left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
                              4. mul-1-negN/A

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

                                \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right)} \]
                              6. lower-sqrt.f64N/A

                                \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                              7. lower-/.f64N/A

                                \[\leadsto \sqrt{\color{blue}{\frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos K}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                              8. +-commutativeN/A

                                \[\leadsto \sqrt{\frac{1}{\color{blue}{\frac{1}{2} \cdot \cos K + \frac{1}{2}}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                              9. lower-fma.f64N/A

                                \[\leadsto \sqrt{\frac{1}{\color{blue}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}}} \cdot \left(-1 \cdot \left(U \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)\right) \]
                              10. lower-cos.f64N/A

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

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
                              12. lower-*.f64N/A

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \color{blue}{\left(\left(-1 \cdot U\right) \cdot \cos \left(\frac{1}{2} \cdot K\right)\right)} \]
                              13. mul-1-negN/A

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
                              14. lower-neg.f64N/A

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\color{blue}{\left(\mathsf{neg}\left(U\right)\right)} \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) \]
                              15. lower-cos.f64N/A

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(\frac{1}{2}, \cos K, \frac{1}{2}\right)}} \cdot \left(\left(\mathsf{neg}\left(U\right)\right) \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                              16. lower-*.f6443.4

                                \[\leadsto \sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}\right) \]
                            7. Applied rewrites43.4%

                              \[\leadsto \color{blue}{\sqrt{\frac{1}{\mathsf{fma}\left(0.5, \cos K, 0.5\right)}} \cdot \left(\left(-U\right) \cdot \cos \left(0.5 \cdot K\right)\right)} \]
                            8. Step-by-step derivation
                              1. Applied rewrites43.5%

                                \[\leadsto \color{blue}{\frac{\cos \left(K \cdot 0.5\right) \cdot \left(-U\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}} \]
                            9. Recombined 3 regimes into one program.
                            10. Final simplification74.7%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot \frac{U}{J}}{J}, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-U\right) \cdot \cos \left(K \cdot 0.5\right)}{\sqrt{\mathsf{fma}\left(\cos K, 0.5, 0.5\right)}}\\ \end{array} \]
                            11. Add Preprocessing

                            Alternative 10: 83.5% accurate, 0.4× speedup?

                            \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(-2 \cdot J\right) \cdot t\_0\\ t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_2 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;t\_1 \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot \frac{U\_m}{J}}{J}, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\ \end{array} \end{array} \]
                            U_m = (fabs.f64 U)
                            (FPCore (J K U_m)
                             :precision binary64
                             (let* ((t_0 (cos (/ K 2.0)))
                                    (t_1 (* (* -2.0 J) t_0))
                                    (t_2 (* t_1 (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
                               (if (<= t_2 (- INFINITY))
                                 (- U_m)
                                 (if (<= t_2 5e+301)
                                   (* t_1 (sqrt (fma 0.25 (/ (* U_m (/ U_m J)) J) 1.0)))
                                   (* (* -2.0 J) (* (/ U_m J) -0.5))))))
                            U_m = fabs(U);
                            double code(double J, double K, double U_m) {
                            	double t_0 = cos((K / 2.0));
                            	double t_1 = (-2.0 * J) * t_0;
                            	double t_2 = t_1 * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                            	double tmp;
                            	if (t_2 <= -((double) INFINITY)) {
                            		tmp = -U_m;
                            	} else if (t_2 <= 5e+301) {
                            		tmp = t_1 * sqrt(fma(0.25, ((U_m * (U_m / J)) / J), 1.0));
                            	} else {
                            		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
                            	}
                            	return tmp;
                            }
                            
                            U_m = abs(U)
                            function code(J, K, U_m)
                            	t_0 = cos(Float64(K / 2.0))
                            	t_1 = Float64(Float64(-2.0 * J) * t_0)
                            	t_2 = Float64(t_1 * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
                            	tmp = 0.0
                            	if (t_2 <= Float64(-Inf))
                            		tmp = Float64(-U_m);
                            	elseif (t_2 <= 5e+301)
                            		tmp = Float64(t_1 * sqrt(fma(0.25, Float64(Float64(U_m * Float64(U_m / J)) / J), 1.0)));
                            	else
                            		tmp = Float64(Float64(-2.0 * J) * Float64(Float64(U_m / J) * -0.5));
                            	end
                            	return tmp
                            end
                            
                            U_m = N[Abs[U], $MachinePrecision]
                            code[J_, K_, U$95$m_] := Block[{t$95$0 = N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(-2.0 * J), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(t$95$1 * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, (-Infinity)], (-U$95$m), If[LessEqual[t$95$2, 5e+301], N[(t$95$1 * N[Sqrt[N[(0.25 * N[(N[(U$95$m * N[(U$95$m / J), $MachinePrecision]), $MachinePrecision] / J), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * J), $MachinePrecision] * N[(N[(U$95$m / J), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]]]]]]
                            
                            \begin{array}{l}
                            U_m = \left|U\right|
                            
                            \\
                            \begin{array}{l}
                            t_0 := \cos \left(\frac{K}{2}\right)\\
                            t_1 := \left(-2 \cdot J\right) \cdot t\_0\\
                            t_2 := t\_1 \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                            \mathbf{if}\;t\_2 \leq -\infty:\\
                            \;\;\;\;-U\_m\\
                            
                            \mathbf{elif}\;t\_2 \leq 5 \cdot 10^{+301}:\\
                            \;\;\;\;t\_1 \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U\_m \cdot \frac{U\_m}{J}}{J}, 1\right)}\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\
                            
                            
                            \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 5.3%

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

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

                                  \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                                2. lower-neg.f6450.4

                                  \[\leadsto \color{blue}{-U} \]
                              5. Applied rewrites50.4%

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

                              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))))) < 5.0000000000000004e301

                              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
                              3. Taylor expanded in K around 0

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
                              4. Step-by-step derivation
                                1. lower-sqrt.f64N/A

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

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

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

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                                5. unpow2N/A

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

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                                7. unpow2N/A

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                                8. lower-*.f6471.8

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                              5. Applied rewrites71.8%

                                \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
                              6. Step-by-step derivation
                                1. Applied rewrites86.2%

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{\frac{U}{J} \cdot U}{J}, 1\right)} \]

                                if 5.0000000000000004e301 < (*.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 12.5%

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

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
                                4. Step-by-step derivation
                                  1. lower-sqrt.f64N/A

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

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

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

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                                  5. unpow2N/A

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

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                                  7. unpow2N/A

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                                  8. lower-*.f647.8

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                                5. Applied rewrites7.8%

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
                                6. Taylor expanded in U around inf

                                  \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{J} + \frac{J}{{U}^{2}}\right)}\right) \]
                                7. Step-by-step derivation
                                  1. Applied rewrites20.0%

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{J}{U \cdot U} + \frac{0.5}{J}\right)}\right) \]
                                  2. Step-by-step derivation
                                    1. lift-*.f64N/A

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

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

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

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

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

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

                                      \[\leadsto \color{blue}{\left(\cos \left(\frac{K}{2}\right) \cdot \left(U \cdot \left(\frac{J}{U \cdot U} + \frac{\frac{1}{2}}{J}\right)\right)\right) \cdot \left(J \cdot -2\right)} \]
                                  3. Applied rewrites20.0%

                                    \[\leadsto \color{blue}{\left(\mathsf{fma}\left(U, \frac{0.5}{J}, \frac{J}{U}\right) \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot -2\right)} \]
                                  4. Taylor expanded in U around -inf

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

                                      \[\leadsto \color{blue}{\left(\frac{-1}{2} \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                                    2. lower-/.f6430.0

                                      \[\leadsto \left(-0.5 \cdot \color{blue}{\frac{U}{J}}\right) \cdot \left(J \cdot -2\right) \]
                                  6. Applied rewrites30.0%

                                    \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                                8. Recombined 3 regimes into one program.
                                9. Final simplification72.5%

                                  \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot \frac{U}{J}}{J}, 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U}{J} \cdot -0.5\right)\\ \end{array} \]
                                10. Add Preprocessing

                                Alternative 11: 72.7% accurate, 0.4× speedup?

                                \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\ \end{array} \end{array} \]
                                U_m = (fabs.f64 U)
                                (FPCore (J K U_m)
                                 :precision binary64
                                 (let* ((t_0 (cos (/ K 2.0)))
                                        (t_1
                                         (*
                                          (* (* -2.0 J) t_0)
                                          (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
                                   (if (<= t_1 (- INFINITY))
                                     (- U_m)
                                     (if (<= t_1 5e+301)
                                       (* (* -2.0 J) (cos (* K 0.5)))
                                       (* (* -2.0 J) (* (/ U_m J) -0.5))))))
                                U_m = fabs(U);
                                double code(double J, double K, double U_m) {
                                	double t_0 = cos((K / 2.0));
                                	double t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                                	double tmp;
                                	if (t_1 <= -((double) INFINITY)) {
                                		tmp = -U_m;
                                	} else if (t_1 <= 5e+301) {
                                		tmp = (-2.0 * J) * cos((K * 0.5));
                                	} else {
                                		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
                                	}
                                	return tmp;
                                }
                                
                                U_m = Math.abs(U);
                                public static double code(double J, double K, double U_m) {
                                	double t_0 = Math.cos((K / 2.0));
                                	double t_1 = ((-2.0 * J) * t_0) * Math.sqrt((1.0 + Math.pow((U_m / (t_0 * (J * 2.0))), 2.0)));
                                	double tmp;
                                	if (t_1 <= -Double.POSITIVE_INFINITY) {
                                		tmp = -U_m;
                                	} else if (t_1 <= 5e+301) {
                                		tmp = (-2.0 * J) * Math.cos((K * 0.5));
                                	} else {
                                		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
                                	}
                                	return tmp;
                                }
                                
                                U_m = math.fabs(U)
                                def code(J, K, U_m):
                                	t_0 = math.cos((K / 2.0))
                                	t_1 = ((-2.0 * J) * t_0) * math.sqrt((1.0 + math.pow((U_m / (t_0 * (J * 2.0))), 2.0)))
                                	tmp = 0
                                	if t_1 <= -math.inf:
                                		tmp = -U_m
                                	elif t_1 <= 5e+301:
                                		tmp = (-2.0 * J) * math.cos((K * 0.5))
                                	else:
                                		tmp = (-2.0 * J) * ((U_m / J) * -0.5)
                                	return tmp
                                
                                U_m = abs(U)
                                function code(J, K, U_m)
                                	t_0 = cos(Float64(K / 2.0))
                                	t_1 = Float64(Float64(Float64(-2.0 * J) * t_0) * sqrt(Float64(1.0 + (Float64(U_m / Float64(t_0 * Float64(J * 2.0))) ^ 2.0))))
                                	tmp = 0.0
                                	if (t_1 <= Float64(-Inf))
                                		tmp = Float64(-U_m);
                                	elseif (t_1 <= 5e+301)
                                		tmp = Float64(Float64(-2.0 * J) * cos(Float64(K * 0.5)));
                                	else
                                		tmp = Float64(Float64(-2.0 * J) * Float64(Float64(U_m / J) * -0.5));
                                	end
                                	return tmp
                                end
                                
                                U_m = abs(U);
                                function tmp_2 = code(J, K, U_m)
                                	t_0 = cos((K / 2.0));
                                	t_1 = ((-2.0 * J) * t_0) * sqrt((1.0 + ((U_m / (t_0 * (J * 2.0))) ^ 2.0)));
                                	tmp = 0.0;
                                	if (t_1 <= -Inf)
                                		tmp = -U_m;
                                	elseif (t_1 <= 5e+301)
                                		tmp = (-2.0 * J) * cos((K * 0.5));
                                	else
                                		tmp = (-2.0 * J) * ((U_m / J) * -0.5);
                                	end
                                	tmp_2 = tmp;
                                end
                                
                                U_m = N[Abs[U], $MachinePrecision]
                                code[J_, 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), $MachinePrecision] * t$95$0), $MachinePrecision] * N[Sqrt[N[(1.0 + N[Power[N[(U$95$m / N[(t$95$0 * N[(J * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, (-Infinity)], (-U$95$m), If[LessEqual[t$95$1, 5e+301], N[(N[(-2.0 * J), $MachinePrecision] * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * J), $MachinePrecision] * N[(N[(U$95$m / J), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]]]]]
                                
                                \begin{array}{l}
                                U_m = \left|U\right|
                                
                                \\
                                \begin{array}{l}
                                t_0 := \cos \left(\frac{K}{2}\right)\\
                                t_1 := \left(\left(-2 \cdot J\right) \cdot t\_0\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\
                                \mathbf{if}\;t\_1 \leq -\infty:\\
                                \;\;\;\;-U\_m\\
                                
                                \mathbf{elif}\;t\_1 \leq 5 \cdot 10^{+301}:\\
                                \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U\_m}{J} \cdot -0.5\right)\\
                                
                                
                                \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 5.3%

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

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

                                      \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                                    2. lower-neg.f6450.4

                                      \[\leadsto \color{blue}{-U} \]
                                  5. Applied rewrites50.4%

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

                                  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))))) < 5.0000000000000004e301

                                  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
                                  3. Taylor expanded in U around 0

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

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

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

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

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

                                      \[\leadsto \cos \color{blue}{\left(\frac{1}{2} \cdot K\right)} \cdot \left(-2 \cdot J\right) \]
                                    6. lower-*.f6473.0

                                      \[\leadsto \cos \left(0.5 \cdot K\right) \cdot \color{blue}{\left(-2 \cdot J\right)} \]
                                  5. Applied rewrites73.0%

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

                                  if 5.0000000000000004e301 < (*.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 12.5%

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

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{1}{4} \cdot \frac{{U}^{2}}{{J}^{2}}}} \]
                                  4. Step-by-step derivation
                                    1. lower-sqrt.f64N/A

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

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

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

                                      \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \color{blue}{\frac{{U}^{2}}{{J}^{2}}}, 1\right)} \]
                                    5. unpow2N/A

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

                                      \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{\color{blue}{U \cdot U}}{{J}^{2}}, 1\right)} \]
                                    7. unpow2N/A

                                      \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(\frac{1}{4}, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                                    8. lower-*.f647.8

                                      \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{\color{blue}{J \cdot J}}, 1\right)} \]
                                  5. Applied rewrites7.8%

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{\mathsf{fma}\left(0.25, \frac{U \cdot U}{J \cdot J}, 1\right)}} \]
                                  6. Taylor expanded in U around inf

                                    \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{J} + \frac{J}{{U}^{2}}\right)}\right) \]
                                  7. Step-by-step derivation
                                    1. Applied rewrites20.0%

                                      \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \left(U \cdot \color{blue}{\left(\frac{J}{U \cdot U} + \frac{0.5}{J}\right)}\right) \]
                                    2. Step-by-step derivation
                                      1. lift-*.f64N/A

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

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

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

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

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

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

                                        \[\leadsto \color{blue}{\left(\cos \left(\frac{K}{2}\right) \cdot \left(U \cdot \left(\frac{J}{U \cdot U} + \frac{\frac{1}{2}}{J}\right)\right)\right) \cdot \left(J \cdot -2\right)} \]
                                    3. Applied rewrites20.0%

                                      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(U, \frac{0.5}{J}, \frac{J}{U}\right) \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot -2\right)} \]
                                    4. Taylor expanded in U around -inf

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

                                        \[\leadsto \color{blue}{\left(\frac{-1}{2} \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                                      2. lower-/.f6430.0

                                        \[\leadsto \left(-0.5 \cdot \color{blue}{\frac{U}{J}}\right) \cdot \left(J \cdot -2\right) \]
                                    6. Applied rewrites30.0%

                                      \[\leadsto \color{blue}{\left(-0.5 \cdot \frac{U}{J}\right)} \cdot \left(J \cdot -2\right) \]
                                  8. Recombined 3 regimes into one program.
                                  9. Final simplification63.1%

                                    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq -\infty:\\ \;\;\;\;-U\\ \mathbf{elif}\;\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\cos \left(\frac{K}{2}\right) \cdot \left(J \cdot 2\right)}\right)}^{2}} \leq 5 \cdot 10^{+301}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-2 \cdot J\right) \cdot \left(\frac{U}{J} \cdot -0.5\right)\\ \end{array} \]
                                  10. Add Preprocessing

                                  Alternative 12: 32.2% accurate, 31.0× speedup?

                                  \[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;J \leq 2 \cdot 10^{+39}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\\ \end{array} \end{array} \]
                                  U_m = (fabs.f64 U)
                                  (FPCore (J K U_m) :precision binary64 (if (<= J 2e+39) (- U_m) (* -2.0 J)))
                                  U_m = fabs(U);
                                  double code(double J, double K, double U_m) {
                                  	double tmp;
                                  	if (J <= 2e+39) {
                                  		tmp = -U_m;
                                  	} else {
                                  		tmp = -2.0 * J;
                                  	}
                                  	return tmp;
                                  }
                                  
                                  U_m = abs(u)
                                  real(8) function code(j, k, u_m)
                                      real(8), intent (in) :: j
                                      real(8), intent (in) :: k
                                      real(8), intent (in) :: u_m
                                      real(8) :: tmp
                                      if (j <= 2d+39) then
                                          tmp = -u_m
                                      else
                                          tmp = (-2.0d0) * j
                                      end if
                                      code = tmp
                                  end function
                                  
                                  U_m = Math.abs(U);
                                  public static double code(double J, double K, double U_m) {
                                  	double tmp;
                                  	if (J <= 2e+39) {
                                  		tmp = -U_m;
                                  	} else {
                                  		tmp = -2.0 * J;
                                  	}
                                  	return tmp;
                                  }
                                  
                                  U_m = math.fabs(U)
                                  def code(J, K, U_m):
                                  	tmp = 0
                                  	if J <= 2e+39:
                                  		tmp = -U_m
                                  	else:
                                  		tmp = -2.0 * J
                                  	return tmp
                                  
                                  U_m = abs(U)
                                  function code(J, K, U_m)
                                  	tmp = 0.0
                                  	if (J <= 2e+39)
                                  		tmp = Float64(-U_m);
                                  	else
                                  		tmp = Float64(-2.0 * J);
                                  	end
                                  	return tmp
                                  end
                                  
                                  U_m = abs(U);
                                  function tmp_2 = code(J, K, U_m)
                                  	tmp = 0.0;
                                  	if (J <= 2e+39)
                                  		tmp = -U_m;
                                  	else
                                  		tmp = -2.0 * J;
                                  	end
                                  	tmp_2 = tmp;
                                  end
                                  
                                  U_m = N[Abs[U], $MachinePrecision]
                                  code[J_, K_, U$95$m_] := If[LessEqual[J, 2e+39], (-U$95$m), N[(-2.0 * J), $MachinePrecision]]
                                  
                                  \begin{array}{l}
                                  U_m = \left|U\right|
                                  
                                  \\
                                  \begin{array}{l}
                                  \mathbf{if}\;J \leq 2 \cdot 10^{+39}:\\
                                  \;\;\;\;-U\_m\\
                                  
                                  \mathbf{else}:\\
                                  \;\;\;\;-2 \cdot J\\
                                  
                                  
                                  \end{array}
                                  \end{array}
                                  
                                  Derivation
                                  1. Split input into 2 regimes
                                  2. if J < 1.99999999999999988e39

                                    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 U around inf

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

                                        \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                                      2. lower-neg.f6431.6

                                        \[\leadsto \color{blue}{-U} \]
                                    5. Applied rewrites31.6%

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

                                    if 1.99999999999999988e39 < J

                                    1. Initial program 98.2%

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

                                      \[\leadsto \color{blue}{-2 \cdot \left(J \cdot \cos \left(\frac{1}{2} \cdot K\right)\right) + \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}} \]
                                    4. Step-by-step derivation
                                      1. lower-fma.f64N/A

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

                                        \[\leadsto \mathsf{fma}\left(-2, \color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                                      3. lower-cos.f64N/A

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

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \color{blue}{\left(\frac{1}{2} \cdot K\right)}, \frac{-1}{4} \cdot \frac{{U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                                      5. associate-*r/N/A

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \color{blue}{\frac{\frac{-1}{4} \cdot {U}^{2}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                                      6. lower-/.f64N/A

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

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\color{blue}{\frac{-1}{4} \cdot {U}^{2}}}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}\right) \]
                                      8. unpow2N/A

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

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

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{\color{blue}{J \cdot \cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                                      11. lower-cos.f64N/A

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(\frac{1}{2} \cdot K\right), \frac{\frac{-1}{4} \cdot \left(U \cdot U\right)}{J \cdot \color{blue}{\cos \left(\frac{1}{2} \cdot K\right)}}\right) \]
                                      12. lower-*.f6480.1

                                        \[\leadsto \mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}}\right) \]
                                    5. Applied rewrites80.1%

                                      \[\leadsto \color{blue}{\mathsf{fma}\left(-2, J \cdot \cos \left(0.5 \cdot K\right), \frac{-0.25 \cdot \left(U \cdot U\right)}{J \cdot \cos \left(0.5 \cdot K\right)}\right)} \]
                                    6. Taylor expanded in K around 0

                                      \[\leadsto -2 \cdot J + \color{blue}{\left(\frac{-1}{4} \cdot \frac{{U}^{2}}{J} + {K}^{2} \cdot \left(\frac{-1}{32} \cdot \frac{{U}^{2}}{J} + \frac{1}{4} \cdot J\right)\right)} \]
                                    7. Step-by-step derivation
                                      1. Applied rewrites38.6%

                                        \[\leadsto \mathsf{fma}\left(K, \color{blue}{K \cdot \mathsf{fma}\left(0.25, J, \frac{U \cdot U}{J} \cdot -0.03125\right)}, \mathsf{fma}\left(J, -2, \frac{\left(U \cdot U\right) \cdot -0.25}{J}\right)\right) \]
                                      2. Taylor expanded in J around inf

                                        \[\leadsto J \cdot \left(\frac{1}{4} \cdot {K}^{2} - \color{blue}{2}\right) \]
                                      3. Step-by-step derivation
                                        1. Applied rewrites41.0%

                                          \[\leadsto J \cdot \mathsf{fma}\left(0.25, \color{blue}{K \cdot K}, -2\right) \]
                                        2. Taylor expanded in K around 0

                                          \[\leadsto -2 \cdot J \]
                                        3. Step-by-step derivation
                                          1. Applied rewrites43.5%

                                            \[\leadsto J \cdot -2 \]
                                        4. Recombined 2 regimes into one program.
                                        5. Final simplification34.4%

                                          \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 2 \cdot 10^{+39}:\\ \;\;\;\;-U\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\\ \end{array} \]
                                        6. Add Preprocessing

                                        Alternative 13: 27.0% accurate, 124.3× speedup?

                                        \[\begin{array}{l} U_m = \left|U\right| \\ -U\_m \end{array} \]
                                        U_m = (fabs.f64 U)
                                        (FPCore (J K U_m) :precision binary64 (- U_m))
                                        U_m = fabs(U);
                                        double code(double J, double K, double U_m) {
                                        	return -U_m;
                                        }
                                        
                                        U_m = abs(u)
                                        real(8) function code(j, k, u_m)
                                            real(8), intent (in) :: j
                                            real(8), intent (in) :: k
                                            real(8), intent (in) :: u_m
                                            code = -u_m
                                        end function
                                        
                                        U_m = Math.abs(U);
                                        public static double code(double J, double K, double U_m) {
                                        	return -U_m;
                                        }
                                        
                                        U_m = math.fabs(U)
                                        def code(J, K, U_m):
                                        	return -U_m
                                        
                                        U_m = abs(U)
                                        function code(J, K, U_m)
                                        	return Float64(-U_m)
                                        end
                                        
                                        U_m = abs(U);
                                        function tmp = code(J, K, U_m)
                                        	tmp = -U_m;
                                        end
                                        
                                        U_m = N[Abs[U], $MachinePrecision]
                                        code[J_, K_, U$95$m_] := (-U$95$m)
                                        
                                        \begin{array}{l}
                                        U_m = \left|U\right|
                                        
                                        \\
                                        -U\_m
                                        \end{array}
                                        
                                        Derivation
                                        1. Initial program 73.7%

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

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

                                            \[\leadsto \color{blue}{\mathsf{neg}\left(U\right)} \]
                                          2. lower-neg.f6426.8

                                            \[\leadsto \color{blue}{-U} \]
                                        5. Applied rewrites26.8%

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

                                        Reproduce

                                        ?
                                        herbie shell --seed 2024227 
                                        (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)))))