Maksimov and Kolovsky, Equation (3)

Percentage Accurate: 73.5% → 99.6%
Time: 12.1s
Alternatives: 10
Speedup: 0.3×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 10 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: 73.5% 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?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := \left(t\_0 \cdot \left(-2 \cdot J\right)\right) \cdot \sqrt{1 + {\left(\frac{U\_m}{t\_0 \cdot \left(J \cdot 2\right)}\right)}^{2}}\\ \mathbf{if}\;t\_1 \leq -\infty:\\ \;\;\;\;-U\_m\\ \mathbf{elif}\;t\_1 \leq 2 \cdot 10^{+305}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;U\_m\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0)))
        (t_1
         (*
          (* t_0 (* -2.0 J))
          (sqrt (+ 1.0 (pow (/ U_m (* t_0 (* J 2.0))) 2.0))))))
   (if (<= t_1 (- INFINITY)) (- U_m) (if (<= t_1 2e+305) t_1 U_m))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double t_0 = cos((K / 2.0));
	double t_1 = (t_0 * (-2.0 * J)) * 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 <= 2e+305) {
		tmp = t_1;
	} else {
		tmp = U_m;
	}
	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 = (t_0 * (-2.0 * J)) * 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 <= 2e+305) {
		tmp = t_1;
	} else {
		tmp = U_m;
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	t_0 = math.cos((K / 2.0))
	t_1 = (t_0 * (-2.0 * J)) * 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 <= 2e+305:
		tmp = t_1
	else:
		tmp = U_m
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	t_0 = cos(Float64(K / 2.0))
	t_1 = Float64(Float64(t_0 * Float64(-2.0 * J)) * 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 <= 2e+305)
		tmp = t_1;
	else
		tmp = U_m;
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	t_0 = cos((K / 2.0));
	t_1 = (t_0 * (-2.0 * J)) * 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 <= 2e+305)
		tmp = t_1;
	else
		tmp = U_m;
	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[(t$95$0 * N[(-2.0 * J), $MachinePrecision]), $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, 2e+305], t$95$1, U$95$m]]]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
t_1 := \left(t\_0 \cdot \left(-2 \cdot J\right)\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 2 \cdot 10^{+305}:\\
\;\;\;\;t\_1\\

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


\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 5.2%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified58.5%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in J around 0 50.4%

      \[\leadsto \color{blue}{-1 \cdot U} \]
    5. Step-by-step derivation
      1. neg-mul-150.4%

        \[\leadsto \color{blue}{-U} \]
    6. Simplified50.4%

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

    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))))) < 1.9999999999999999e305

    1. Initial program 99.7%

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

    if 1.9999999999999999e305 < (*.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 5.2%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified66.5%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in U around -inf 47.0%

      \[\leadsto \color{blue}{U} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification87.8%

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

Alternative 2: 51.0% accurate, 1.3× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := \cos \left(\frac{K}{2}\right)\\ t_1 := J \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{if}\;J \leq 6.6 \cdot 10^{-248}:\\ \;\;\;\;-2 \cdot \left(t\_1 \cdot \frac{t\_1}{U\_m}\right) - U\_m\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot t\_0\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{2}}{J \cdot t\_0}\right)\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (let* ((t_0 (cos (/ K 2.0))) (t_1 (* J (cos (* K 0.5)))))
   (if (<= J 6.6e-248)
     (- (* -2.0 (* t_1 (/ t_1 U_m))) U_m)
     (* J (* (* -2.0 t_0) (hypot 1.0 (/ (/ U_m 2.0) (* J t_0))))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double t_0 = cos((K / 2.0));
	double t_1 = J * cos((K * 0.5));
	double tmp;
	if (J <= 6.6e-248) {
		tmp = (-2.0 * (t_1 * (t_1 / U_m))) - U_m;
	} else {
		tmp = J * ((-2.0 * t_0) * hypot(1.0, ((U_m / 2.0) / (J * t_0))));
	}
	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 = J * Math.cos((K * 0.5));
	double tmp;
	if (J <= 6.6e-248) {
		tmp = (-2.0 * (t_1 * (t_1 / U_m))) - U_m;
	} else {
		tmp = J * ((-2.0 * t_0) * Math.hypot(1.0, ((U_m / 2.0) / (J * t_0))));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	t_0 = math.cos((K / 2.0))
	t_1 = J * math.cos((K * 0.5))
	tmp = 0
	if J <= 6.6e-248:
		tmp = (-2.0 * (t_1 * (t_1 / U_m))) - U_m
	else:
		tmp = J * ((-2.0 * t_0) * math.hypot(1.0, ((U_m / 2.0) / (J * t_0))))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	t_0 = cos(Float64(K / 2.0))
	t_1 = Float64(J * cos(Float64(K * 0.5)))
	tmp = 0.0
	if (J <= 6.6e-248)
		tmp = Float64(Float64(-2.0 * Float64(t_1 * Float64(t_1 / U_m))) - U_m);
	else
		tmp = Float64(J * Float64(Float64(-2.0 * t_0) * hypot(1.0, Float64(Float64(U_m / 2.0) / Float64(J * t_0)))));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	t_0 = cos((K / 2.0));
	t_1 = J * cos((K * 0.5));
	tmp = 0.0;
	if (J <= 6.6e-248)
		tmp = (-2.0 * (t_1 * (t_1 / U_m))) - U_m;
	else
		tmp = J * ((-2.0 * t_0) * hypot(1.0, ((U_m / 2.0) / (J * t_0))));
	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[(J * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[J, 6.6e-248], N[(N[(-2.0 * N[(t$95$1 * N[(t$95$1 / U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - U$95$m), $MachinePrecision], N[(J * N[(N[(-2.0 * t$95$0), $MachinePrecision] * N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / 2.0), $MachinePrecision] / N[(J * t$95$0), $MachinePrecision]), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
t_0 := \cos \left(\frac{K}{2}\right)\\
t_1 := J \cdot \cos \left(K \cdot 0.5\right)\\
\mathbf{if}\;J \leq 6.6 \cdot 10^{-248}:\\
\;\;\;\;-2 \cdot \left(t\_1 \cdot \frac{t\_1}{U\_m}\right) - U\_m\\

\mathbf{else}:\\
\;\;\;\;J \cdot \left(\left(-2 \cdot t\_0\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{2}}{J \cdot t\_0}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 6.6000000000000004e-248

    1. Initial program 78.4%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Step-by-step derivation
      1. unpow278.4%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      2. hypot-1-def88.9%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\mathsf{hypot}\left(1, \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)} \]
      3. associate-/r*88.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}}\right) \]
      4. cos-neg88.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(-\frac{K}{2}\right)}}\right) \]
      5. distribute-frac-neg88.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\cos \color{blue}{\left(\frac{-K}{2}\right)}}\right) \]
      6. associate-/r*88.9%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}\right) \]
      7. hypot-1-def78.4%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}} \]
      8. unpow278.4%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}\right)}^{2}}} \]
    3. Simplified88.8%

      \[\leadsto \color{blue}{\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u88.8%

        \[\leadsto \left(J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(\frac{K}{2}\right)\right)\right)}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
      2. div-inv88.8%

        \[\leadsto \left(J \cdot \left(-2 \cdot \mathsf{expm1}\left(\mathsf{log1p}\left(\cos \color{blue}{\left(K \cdot \frac{1}{2}\right)}\right)\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
      3. metadata-eval88.8%

        \[\leadsto \left(J \cdot \left(-2 \cdot \mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot \color{blue}{0.5}\right)\right)\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
    6. Applied egg-rr88.8%

      \[\leadsto \left(J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot 0.5\right)\right)\right)}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
    7. Taylor expanded in J around 0 24.6%

      \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} + -1 \cdot U} \]
    8. Step-by-step derivation
      1. mul-1-neg24.6%

        \[\leadsto -2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} + \color{blue}{\left(-U\right)} \]
      2. unsub-neg24.6%

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} - U} \]
      3. unpow224.6%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot J\right)} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} - U \]
      4. *-commutative24.6%

        \[\leadsto -2 \cdot \frac{\left(J \cdot J\right) \cdot {\cos \color{blue}{\left(K \cdot 0.5\right)}}^{2}}{U} - U \]
      5. unpow224.6%

        \[\leadsto -2 \cdot \frac{\left(J \cdot J\right) \cdot \color{blue}{\left(\cos \left(K \cdot 0.5\right) \cdot \cos \left(K \cdot 0.5\right)\right)}}{U} - U \]
      6. swap-sqr24.6%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot \cos \left(K \cdot 0.5\right)\right)}}{U} - U \]
      7. unpow224.6%

        \[\leadsto -2 \cdot \frac{\color{blue}{{\left(J \cdot \cos \left(K \cdot 0.5\right)\right)}^{2}}}{U} - U \]
      8. *-commutative24.6%

        \[\leadsto -2 \cdot \frac{{\left(J \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}\right)}^{2}}{U} - U \]
    9. Simplified24.6%

      \[\leadsto \color{blue}{-2 \cdot \frac{{\left(J \cdot \cos \left(0.5 \cdot K\right)\right)}^{2}}{U} - U} \]
    10. Step-by-step derivation
      1. unpow224.6%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot \cos \left(0.5 \cdot K\right)\right) \cdot \left(J \cdot \cos \left(0.5 \cdot K\right)\right)}}{U} - U \]
      2. associate-/l*27.4%

        \[\leadsto -2 \cdot \color{blue}{\left(\left(J \cdot \cos \left(0.5 \cdot K\right)\right) \cdot \frac{J \cdot \cos \left(0.5 \cdot K\right)}{U}\right)} - U \]
      3. *-commutative27.4%

        \[\leadsto -2 \cdot \left(\left(J \cdot \cos \color{blue}{\left(K \cdot 0.5\right)}\right) \cdot \frac{J \cdot \cos \left(0.5 \cdot K\right)}{U}\right) - U \]
      4. *-commutative27.4%

        \[\leadsto -2 \cdot \left(\left(J \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \frac{J \cdot \cos \color{blue}{\left(K \cdot 0.5\right)}}{U}\right) - U \]
    11. Applied egg-rr27.4%

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

    if 6.6000000000000004e-248 < J

    1. Initial program 76.6%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified93.3%

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

Alternative 3: 45.6% accurate, 1.9× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} t_0 := J \cdot \cos \left(K \cdot 0.5\right)\\ \mathbf{if}\;J \leq 8.8 \cdot 10^{-178}:\\ \;\;\;\;-2 \cdot \left(t\_0 \cdot \frac{t\_0}{U\_m}\right) - U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{2}}{J}\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (let* ((t_0 (* J (cos (* K 0.5)))))
   (if (<= J 8.8e-178)
     (- (* -2.0 (* t_0 (/ t_0 U_m))) U_m)
     (* (* J (* -2.0 (cos (/ K 2.0)))) (hypot 1.0 (/ (/ U_m 2.0) J))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double t_0 = J * cos((K * 0.5));
	double tmp;
	if (J <= 8.8e-178) {
		tmp = (-2.0 * (t_0 * (t_0 / U_m))) - U_m;
	} else {
		tmp = (J * (-2.0 * cos((K / 2.0)))) * hypot(1.0, ((U_m / 2.0) / J));
	}
	return tmp;
}
U_m = Math.abs(U);
public static double code(double J, double K, double U_m) {
	double t_0 = J * Math.cos((K * 0.5));
	double tmp;
	if (J <= 8.8e-178) {
		tmp = (-2.0 * (t_0 * (t_0 / U_m))) - U_m;
	} else {
		tmp = (J * (-2.0 * Math.cos((K / 2.0)))) * Math.hypot(1.0, ((U_m / 2.0) / J));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	t_0 = J * math.cos((K * 0.5))
	tmp = 0
	if J <= 8.8e-178:
		tmp = (-2.0 * (t_0 * (t_0 / U_m))) - U_m
	else:
		tmp = (J * (-2.0 * math.cos((K / 2.0)))) * math.hypot(1.0, ((U_m / 2.0) / J))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	t_0 = Float64(J * cos(Float64(K * 0.5)))
	tmp = 0.0
	if (J <= 8.8e-178)
		tmp = Float64(Float64(-2.0 * Float64(t_0 * Float64(t_0 / U_m))) - U_m);
	else
		tmp = Float64(Float64(J * Float64(-2.0 * cos(Float64(K / 2.0)))) * hypot(1.0, Float64(Float64(U_m / 2.0) / J)));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	t_0 = J * cos((K * 0.5));
	tmp = 0.0;
	if (J <= 8.8e-178)
		tmp = (-2.0 * (t_0 * (t_0 / U_m))) - U_m;
	else
		tmp = (J * (-2.0 * cos((K / 2.0)))) * hypot(1.0, ((U_m / 2.0) / J));
	end
	tmp_2 = tmp;
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := Block[{t$95$0 = N[(J * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[J, 8.8e-178], N[(N[(-2.0 * N[(t$95$0 * N[(t$95$0 / U$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - U$95$m), $MachinePrecision], N[(N[(J * N[(-2.0 * N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / 2.0), $MachinePrecision] / J), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
t_0 := J \cdot \cos \left(K \cdot 0.5\right)\\
\mathbf{if}\;J \leq 8.8 \cdot 10^{-178}:\\
\;\;\;\;-2 \cdot \left(t\_0 \cdot \frac{t\_0}{U\_m}\right) - U\_m\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 8.8000000000000005e-178

    1. Initial program 72.3%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Step-by-step derivation
      1. unpow272.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      2. hypot-1-def85.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\mathsf{hypot}\left(1, \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)} \]
      3. associate-/r*85.2%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}}\right) \]
      4. cos-neg85.2%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(-\frac{K}{2}\right)}}\right) \]
      5. distribute-frac-neg85.2%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\cos \color{blue}{\left(\frac{-K}{2}\right)}}\right) \]
      6. associate-/r*85.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}\right) \]
      7. hypot-1-def72.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}} \]
      8. unpow272.3%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}\right)}^{2}}} \]
    3. Simplified85.2%

      \[\leadsto \color{blue}{\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. expm1-log1p-u85.2%

        \[\leadsto \left(J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(\frac{K}{2}\right)\right)\right)}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
      2. div-inv85.2%

        \[\leadsto \left(J \cdot \left(-2 \cdot \mathsf{expm1}\left(\mathsf{log1p}\left(\cos \color{blue}{\left(K \cdot \frac{1}{2}\right)}\right)\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
      3. metadata-eval85.2%

        \[\leadsto \left(J \cdot \left(-2 \cdot \mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot \color{blue}{0.5}\right)\right)\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
    6. Applied egg-rr85.2%

      \[\leadsto \left(J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot 0.5\right)\right)\right)}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right) \]
    7. Taylor expanded in J around 0 27.3%

      \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} + -1 \cdot U} \]
    8. Step-by-step derivation
      1. mul-1-neg27.3%

        \[\leadsto -2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} + \color{blue}{\left(-U\right)} \]
      2. unsub-neg27.3%

        \[\leadsto \color{blue}{-2 \cdot \frac{{J}^{2} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} - U} \]
      3. unpow227.3%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot J\right)} \cdot {\cos \left(0.5 \cdot K\right)}^{2}}{U} - U \]
      4. *-commutative27.3%

        \[\leadsto -2 \cdot \frac{\left(J \cdot J\right) \cdot {\cos \color{blue}{\left(K \cdot 0.5\right)}}^{2}}{U} - U \]
      5. unpow227.3%

        \[\leadsto -2 \cdot \frac{\left(J \cdot J\right) \cdot \color{blue}{\left(\cos \left(K \cdot 0.5\right) \cdot \cos \left(K \cdot 0.5\right)\right)}}{U} - U \]
      6. swap-sqr27.3%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \left(J \cdot \cos \left(K \cdot 0.5\right)\right)}}{U} - U \]
      7. unpow227.3%

        \[\leadsto -2 \cdot \frac{\color{blue}{{\left(J \cdot \cos \left(K \cdot 0.5\right)\right)}^{2}}}{U} - U \]
      8. *-commutative27.3%

        \[\leadsto -2 \cdot \frac{{\left(J \cdot \cos \color{blue}{\left(0.5 \cdot K\right)}\right)}^{2}}{U} - U \]
    9. Simplified27.3%

      \[\leadsto \color{blue}{-2 \cdot \frac{{\left(J \cdot \cos \left(0.5 \cdot K\right)\right)}^{2}}{U} - U} \]
    10. Step-by-step derivation
      1. unpow227.3%

        \[\leadsto -2 \cdot \frac{\color{blue}{\left(J \cdot \cos \left(0.5 \cdot K\right)\right) \cdot \left(J \cdot \cos \left(0.5 \cdot K\right)\right)}}{U} - U \]
      2. associate-/l*29.9%

        \[\leadsto -2 \cdot \color{blue}{\left(\left(J \cdot \cos \left(0.5 \cdot K\right)\right) \cdot \frac{J \cdot \cos \left(0.5 \cdot K\right)}{U}\right)} - U \]
      3. *-commutative29.9%

        \[\leadsto -2 \cdot \left(\left(J \cdot \cos \color{blue}{\left(K \cdot 0.5\right)}\right) \cdot \frac{J \cdot \cos \left(0.5 \cdot K\right)}{U}\right) - U \]
      4. *-commutative29.9%

        \[\leadsto -2 \cdot \left(\left(J \cdot \cos \left(K \cdot 0.5\right)\right) \cdot \frac{J \cdot \cos \color{blue}{\left(K \cdot 0.5\right)}}{U}\right) - U \]
    11. Applied egg-rr29.9%

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

    if 8.8000000000000005e-178 < J

    1. Initial program 85.7%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Step-by-step derivation
      1. unpow285.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      2. hypot-1-def99.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\mathsf{hypot}\left(1, \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)} \]
      3. associate-/r*99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}}\right) \]
      4. cos-neg99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(-\frac{K}{2}\right)}}\right) \]
      5. distribute-frac-neg99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\cos \color{blue}{\left(\frac{-K}{2}\right)}}\right) \]
      6. associate-/r*99.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}\right) \]
      7. hypot-1-def85.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}} \]
      8. unpow285.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}\right)}^{2}}} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in K around 0 81.1%

      \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\color{blue}{1}}\right) \]
    6. Step-by-step derivation
      1. /-rgt-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{J \cdot 2}}\right) \]
      2. *-un-lft-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\color{blue}{1 \cdot U}}{J \cdot 2}\right) \]
      3. times-frac81.0%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1}{J} \cdot \frac{U}{2}}\right) \]
    7. Applied egg-rr81.0%

      \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1}{J} \cdot \frac{U}{2}}\right) \]
    8. Step-by-step derivation
      1. associate-*l/81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1 \cdot \frac{U}{2}}{J}}\right) \]
      2. *-lft-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\color{blue}{\frac{U}{2}}}{J}\right) \]
    9. Simplified81.1%

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

Alternative 4: 45.7% accurate, 1.9× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;J \leq 2.4 \cdot 10^{-180}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{2}}{J}\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (if (<= J 2.4e-180)
   (- U_m)
   (* (* J (* -2.0 (cos (/ K 2.0)))) (hypot 1.0 (/ (/ U_m 2.0) J)))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 2.4e-180) {
		tmp = -U_m;
	} else {
		tmp = (J * (-2.0 * cos((K / 2.0)))) * hypot(1.0, ((U_m / 2.0) / J));
	}
	return tmp;
}
U_m = Math.abs(U);
public static double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 2.4e-180) {
		tmp = -U_m;
	} else {
		tmp = (J * (-2.0 * Math.cos((K / 2.0)))) * Math.hypot(1.0, ((U_m / 2.0) / J));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	tmp = 0
	if J <= 2.4e-180:
		tmp = -U_m
	else:
		tmp = (J * (-2.0 * math.cos((K / 2.0)))) * math.hypot(1.0, ((U_m / 2.0) / J))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	tmp = 0.0
	if (J <= 2.4e-180)
		tmp = Float64(-U_m);
	else
		tmp = Float64(Float64(J * Float64(-2.0 * cos(Float64(K / 2.0)))) * hypot(1.0, Float64(Float64(U_m / 2.0) / J)));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	tmp = 0.0;
	if (J <= 2.4e-180)
		tmp = -U_m;
	else
		tmp = (J * (-2.0 * cos((K / 2.0)))) * hypot(1.0, ((U_m / 2.0) / J));
	end
	tmp_2 = tmp;
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := If[LessEqual[J, 2.4e-180], (-U$95$m), N[(N[(J * N[(-2.0 * N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / 2.0), $MachinePrecision] / J), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
\mathbf{if}\;J \leq 2.4 \cdot 10^{-180}:\\
\;\;\;\;-U\_m\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 2.39999999999999979e-180

    1. Initial program 72.3%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified85.2%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in J around 0 29.5%

      \[\leadsto \color{blue}{-1 \cdot U} \]
    5. Step-by-step derivation
      1. neg-mul-129.5%

        \[\leadsto \color{blue}{-U} \]
    6. Simplified29.5%

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

    if 2.39999999999999979e-180 < J

    1. Initial program 85.7%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Step-by-step derivation
      1. unpow285.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      2. hypot-1-def99.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\mathsf{hypot}\left(1, \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)} \]
      3. associate-/r*99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}}\right) \]
      4. cos-neg99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(-\frac{K}{2}\right)}}\right) \]
      5. distribute-frac-neg99.6%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\cos \color{blue}{\left(\frac{-K}{2}\right)}}\right) \]
      6. associate-/r*99.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}\right) \]
      7. hypot-1-def85.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}} \]
      8. unpow285.7%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}\right)}^{2}}} \]
    3. Simplified99.6%

      \[\leadsto \color{blue}{\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in K around 0 81.1%

      \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\color{blue}{1}}\right) \]
    6. Step-by-step derivation
      1. /-rgt-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{J \cdot 2}}\right) \]
      2. *-un-lft-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\color{blue}{1 \cdot U}}{J \cdot 2}\right) \]
      3. times-frac81.0%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1}{J} \cdot \frac{U}{2}}\right) \]
    7. Applied egg-rr81.0%

      \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1}{J} \cdot \frac{U}{2}}\right) \]
    8. Step-by-step derivation
      1. associate-*l/81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{1 \cdot \frac{U}{2}}{J}}\right) \]
      2. *-lft-identity81.1%

        \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\color{blue}{\frac{U}{2}}}{J}\right) \]
    9. Simplified81.1%

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

Alternative 5: 45.7% accurate, 1.9× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;J \leq 1.75 \cdot 10^{-179}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U\_m}{2}}{J}\right)\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (if (<= J 1.75e-179)
   (- U_m)
   (* J (* (* -2.0 (cos (/ K 2.0))) (hypot 1.0 (/ (/ U_m 2.0) J))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 1.75e-179) {
		tmp = -U_m;
	} else {
		tmp = J * ((-2.0 * cos((K / 2.0))) * hypot(1.0, ((U_m / 2.0) / J)));
	}
	return tmp;
}
U_m = Math.abs(U);
public static double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 1.75e-179) {
		tmp = -U_m;
	} else {
		tmp = J * ((-2.0 * Math.cos((K / 2.0))) * Math.hypot(1.0, ((U_m / 2.0) / J)));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	tmp = 0
	if J <= 1.75e-179:
		tmp = -U_m
	else:
		tmp = J * ((-2.0 * math.cos((K / 2.0))) * math.hypot(1.0, ((U_m / 2.0) / J)))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	tmp = 0.0
	if (J <= 1.75e-179)
		tmp = Float64(-U_m);
	else
		tmp = Float64(J * Float64(Float64(-2.0 * cos(Float64(K / 2.0))) * hypot(1.0, Float64(Float64(U_m / 2.0) / J))));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	tmp = 0.0;
	if (J <= 1.75e-179)
		tmp = -U_m;
	else
		tmp = J * ((-2.0 * cos((K / 2.0))) * hypot(1.0, ((U_m / 2.0) / J)));
	end
	tmp_2 = tmp;
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := If[LessEqual[J, 1.75e-179], (-U$95$m), N[(J * N[(N[(-2.0 * N[Cos[N[(K / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[1.0 ^ 2 + N[(N[(U$95$m / 2.0), $MachinePrecision] / J), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
\mathbf{if}\;J \leq 1.75 \cdot 10^{-179}:\\
\;\;\;\;-U\_m\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 1.75000000000000012e-179

    1. Initial program 72.3%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified85.2%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in J around 0 29.5%

      \[\leadsto \color{blue}{-1 \cdot U} \]
    5. Step-by-step derivation
      1. neg-mul-129.5%

        \[\leadsto \color{blue}{-U} \]
    6. Simplified29.5%

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

    if 1.75000000000000012e-179 < J

    1. Initial program 85.7%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified99.6%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in K around 0 81.1%

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

Alternative 6: 62.5% accurate, 3.7× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;K \leq 0.011:\\ \;\;\;\;-2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{U\_m}{J \cdot 2}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (if (<= K 0.011)
   (* -2.0 (* J (hypot 1.0 (/ U_m (* J 2.0)))))
   (* J (* -2.0 (cos (* K 0.5))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double tmp;
	if (K <= 0.011) {
		tmp = -2.0 * (J * hypot(1.0, (U_m / (J * 2.0))));
	} else {
		tmp = J * (-2.0 * cos((K * 0.5)));
	}
	return tmp;
}
U_m = Math.abs(U);
public static double code(double J, double K, double U_m) {
	double tmp;
	if (K <= 0.011) {
		tmp = -2.0 * (J * Math.hypot(1.0, (U_m / (J * 2.0))));
	} else {
		tmp = J * (-2.0 * Math.cos((K * 0.5)));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	tmp = 0
	if K <= 0.011:
		tmp = -2.0 * (J * math.hypot(1.0, (U_m / (J * 2.0))))
	else:
		tmp = J * (-2.0 * math.cos((K * 0.5)))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	tmp = 0.0
	if (K <= 0.011)
		tmp = Float64(-2.0 * Float64(J * hypot(1.0, Float64(U_m / Float64(J * 2.0)))));
	else
		tmp = Float64(J * Float64(-2.0 * cos(Float64(K * 0.5))));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	tmp = 0.0;
	if (K <= 0.011)
		tmp = -2.0 * (J * hypot(1.0, (U_m / (J * 2.0))));
	else
		tmp = J * (-2.0 * cos((K * 0.5)));
	end
	tmp_2 = tmp;
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := If[LessEqual[K, 0.011], N[(-2.0 * N[(J * N[Sqrt[1.0 ^ 2 + N[(U$95$m / N[(J * 2.0), $MachinePrecision]), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(J * N[(-2.0 * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
\mathbf{if}\;K \leq 0.011:\\
\;\;\;\;-2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{U\_m}{J \cdot 2}\right)\right)\\

\mathbf{else}:\\
\;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if K < 0.010999999999999999

    1. Initial program 80.8%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Step-by-step derivation
      1. unpow280.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}}} \]
      2. hypot-1-def91.1%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\mathsf{hypot}\left(1, \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)} \]
      3. associate-/r*91.1%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{\frac{U}{2 \cdot J}}{\cos \left(\frac{K}{2}\right)}}\right) \]
      4. cos-neg91.1%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\color{blue}{\cos \left(-\frac{K}{2}\right)}}\right) \]
      5. distribute-frac-neg91.1%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2 \cdot J}}{\cos \color{blue}{\left(\frac{-K}{2}\right)}}\right) \]
      6. associate-/r*91.1%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}\right) \]
      7. hypot-1-def80.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \color{blue}{\sqrt{1 + \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)} \cdot \frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}}} \]
      8. unpow280.8%

        \[\leadsto \left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + \color{blue}{{\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{-K}{2}\right)}\right)}^{2}}} \]
    3. Simplified91.1%

      \[\leadsto \color{blue}{\left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\cos \left(\frac{K}{2}\right)}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in K around 0 82.0%

      \[\leadsto \left(J \cdot \left(-2 \cdot \cos \left(\frac{K}{2}\right)\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{J \cdot 2}}{\color{blue}{1}}\right) \]
    6. Taylor expanded in K around 0 43.7%

      \[\leadsto \color{blue}{-2 \cdot \left(J \cdot \sqrt{1 + 0.25 \cdot \frac{{U}^{2}}{{J}^{2}}}\right)} \]
    7. Step-by-step derivation
      1. metadata-eval43.7%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{\color{blue}{1 \cdot 1} + 0.25 \cdot \frac{{U}^{2}}{{J}^{2}}}\right) \]
      2. metadata-eval43.7%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{1 \cdot 1 + \color{blue}{\left(0.5 \cdot 0.5\right)} \cdot \frac{{U}^{2}}{{J}^{2}}}\right) \]
      3. unpow243.7%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{1 \cdot 1 + \left(0.5 \cdot 0.5\right) \cdot \frac{\color{blue}{U \cdot U}}{{J}^{2}}}\right) \]
      4. unpow243.7%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{1 \cdot 1 + \left(0.5 \cdot 0.5\right) \cdot \frac{U \cdot U}{\color{blue}{J \cdot J}}}\right) \]
      5. times-frac56.6%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{1 \cdot 1 + \left(0.5 \cdot 0.5\right) \cdot \color{blue}{\left(\frac{U}{J} \cdot \frac{U}{J}\right)}}\right) \]
      6. swap-sqr56.6%

        \[\leadsto -2 \cdot \left(J \cdot \sqrt{1 \cdot 1 + \color{blue}{\left(0.5 \cdot \frac{U}{J}\right) \cdot \left(0.5 \cdot \frac{U}{J}\right)}}\right) \]
      7. hypot-undefine66.0%

        \[\leadsto -2 \cdot \left(J \cdot \color{blue}{\mathsf{hypot}\left(1, 0.5 \cdot \frac{U}{J}\right)}\right) \]
      8. metadata-eval66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{-1}{-2}} \cdot \frac{U}{J}\right)\right) \]
      9. times-frac66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{-1 \cdot U}{-2 \cdot J}}\right)\right) \]
      10. neg-mul-166.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{\color{blue}{-U}}{-2 \cdot J}\right)\right) \]
      11. *-commutative66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{-U}{\color{blue}{J \cdot -2}}\right)\right) \]
      12. distribute-frac-neg66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \color{blue}{-\frac{U}{J \cdot -2}}\right)\right) \]
      13. distribute-neg-frac266.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \color{blue}{\frac{U}{-J \cdot -2}}\right)\right) \]
      14. distribute-rgt-neg-in66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{U}{\color{blue}{J \cdot \left(--2\right)}}\right)\right) \]
      15. metadata-eval66.0%

        \[\leadsto -2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{U}{J \cdot \color{blue}{2}}\right)\right) \]
    8. Simplified66.0%

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

    if 0.010999999999999999 < K

    1. Initial program 67.5%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified90.3%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in U around 0 50.8%

      \[\leadsto J \cdot \color{blue}{\left(-2 \cdot \cos \left(0.5 \cdot K\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification62.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;K \leq 0.011:\\ \;\;\;\;-2 \cdot \left(J \cdot \mathsf{hypot}\left(1, \frac{U}{J \cdot 2}\right)\right)\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 40.3% accurate, 3.7× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;J \leq 6.5 \cdot 10^{-7}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m)
 :precision binary64
 (if (<= J 6.5e-7) (- U_m) (* J (* -2.0 (cos (* K 0.5))))))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 6.5e-7) {
		tmp = -U_m;
	} else {
		tmp = J * (-2.0 * cos((K * 0.5)));
	}
	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 <= 6.5d-7) then
        tmp = -u_m
    else
        tmp = j * ((-2.0d0) * cos((k * 0.5d0)))
    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 <= 6.5e-7) {
		tmp = -U_m;
	} else {
		tmp = J * (-2.0 * Math.cos((K * 0.5)));
	}
	return tmp;
}
U_m = math.fabs(U)
def code(J, K, U_m):
	tmp = 0
	if J <= 6.5e-7:
		tmp = -U_m
	else:
		tmp = J * (-2.0 * math.cos((K * 0.5)))
	return tmp
U_m = abs(U)
function code(J, K, U_m)
	tmp = 0.0
	if (J <= 6.5e-7)
		tmp = Float64(-U_m);
	else
		tmp = Float64(J * Float64(-2.0 * cos(Float64(K * 0.5))));
	end
	return tmp
end
U_m = abs(U);
function tmp_2 = code(J, K, U_m)
	tmp = 0.0;
	if (J <= 6.5e-7)
		tmp = -U_m;
	else
		tmp = J * (-2.0 * cos((K * 0.5)));
	end
	tmp_2 = tmp;
end
U_m = N[Abs[U], $MachinePrecision]
code[J_, K_, U$95$m_] := If[LessEqual[J, 6.5e-7], (-U$95$m), N[(J * N[(-2.0 * N[Cos[N[(K * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
\mathbf{if}\;J \leq 6.5 \cdot 10^{-7}:\\
\;\;\;\;-U\_m\\

\mathbf{else}:\\
\;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 6.50000000000000024e-7

    1. Initial program 72.0%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified87.7%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in J around 0 29.9%

      \[\leadsto \color{blue}{-1 \cdot U} \]
    5. Step-by-step derivation
      1. neg-mul-129.9%

        \[\leadsto \color{blue}{-U} \]
    6. Simplified29.9%

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

    if 6.50000000000000024e-7 < J

    1. Initial program 93.0%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified99.7%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in U around 0 72.6%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 6.5 \cdot 10^{-7}:\\ \;\;\;\;-U\\ \mathbf{else}:\\ \;\;\;\;J \cdot \left(-2 \cdot \cos \left(K \cdot 0.5\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 32.3% accurate, 52.4× speedup?

\[\begin{array}{l} U_m = \left|U\right| \\ \begin{array}{l} \mathbf{if}\;J \leq 1.5 \cdot 10^{+37}:\\ \;\;\;\;-U\_m\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\\ \end{array} \end{array} \]
U_m = (fabs.f64 U)
(FPCore (J K U_m) :precision binary64 (if (<= J 1.5e+37) (- U_m) (* -2.0 J)))
U_m = fabs(U);
double code(double J, double K, double U_m) {
	double tmp;
	if (J <= 1.5e+37) {
		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 <= 1.5d+37) 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 <= 1.5e+37) {
		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 <= 1.5e+37:
		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 <= 1.5e+37)
		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 <= 1.5e+37)
		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, 1.5e+37], (-U$95$m), N[(-2.0 * J), $MachinePrecision]]
\begin{array}{l}
U_m = \left|U\right|

\\
\begin{array}{l}
\mathbf{if}\;J \leq 1.5 \cdot 10^{+37}:\\
\;\;\;\;-U\_m\\

\mathbf{else}:\\
\;\;\;\;-2 \cdot J\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if J < 1.50000000000000011e37

    1. Initial program 72.4%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified88.1%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in J around 0 31.1%

      \[\leadsto \color{blue}{-1 \cdot U} \]
    5. Step-by-step derivation
      1. neg-mul-131.1%

        \[\leadsto \color{blue}{-U} \]
    6. Simplified31.1%

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

    if 1.50000000000000011e37 < J

    1. Initial program 93.8%

      \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
    2. Simplified99.7%

      \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
    3. Add Preprocessing
    4. Taylor expanded in U around 0 76.0%

      \[\leadsto J \cdot \color{blue}{\left(-2 \cdot \cos \left(0.5 \cdot K\right)\right)} \]
    5. Step-by-step derivation
      1. *-commutative76.0%

        \[\leadsto J \cdot \left(-2 \cdot \cos \color{blue}{\left(K \cdot 0.5\right)}\right) \]
      2. expm1-log1p-u75.9%

        \[\leadsto J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot 0.5\right)\right)\right)}\right) \]
    6. Applied egg-rr75.9%

      \[\leadsto J \cdot \left(-2 \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\cos \left(K \cdot 0.5\right)\right)\right)}\right) \]
    7. Taylor expanded in K around 0 45.0%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;J \leq 1.5 \cdot 10^{+37}:\\ \;\;\;\;-U\\ \mathbf{else}:\\ \;\;\;\;-2 \cdot J\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 26.4% accurate, 210.0× 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 77.6%

    \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
  2. Simplified90.9%

    \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
  3. Add Preprocessing
  4. Taylor expanded in J around 0 26.5%

    \[\leadsto \color{blue}{-1 \cdot U} \]
  5. Step-by-step derivation
    1. neg-mul-126.5%

      \[\leadsto \color{blue}{-U} \]
  6. Simplified26.5%

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

Alternative 10: 26.3% accurate, 420.0× 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 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 77.6%

    \[\left(\left(-2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \sqrt{1 + {\left(\frac{U}{\left(2 \cdot J\right) \cdot \cos \left(\frac{K}{2}\right)}\right)}^{2}} \]
  2. Simplified90.9%

    \[\leadsto \color{blue}{J \cdot \left(\left(-2 \cdot \cos \left(\frac{K}{2}\right)\right) \cdot \mathsf{hypot}\left(1, \frac{\frac{U}{2}}{J \cdot \cos \left(\frac{K}{2}\right)}\right)\right)} \]
  3. Add Preprocessing
  4. Taylor expanded in U around -inf 22.3%

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

Reproduce

?
herbie shell --seed 2024172 
(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)))))