Migdal et al, Equation (64)

Percentage Accurate: 99.5% → 99.6%
Time: 8.6s
Alternatives: 12
Speedup: 1.9×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right) \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (+ (* t_1 (* a1 a1)) (* t_1 (* a2 a2)))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    real(8) :: t_1
    t_1 = cos(th) / sqrt(2.0d0)
    code = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
end function
public static double code(double a1, double a2, double th) {
	double t_1 = Math.cos(th) / Math.sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
def code(a1, a2, th):
	t_1 = math.cos(th) / math.sqrt(2.0)
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
function code(a1, a2, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	return Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2 * a2)))
end
function tmp = code(a1, a2, th)
	t_1 = cos(th) / sqrt(2.0);
	tmp = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right)
\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 12 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: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right) \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (+ (* t_1 (* a1 a1)) (* t_1 (* a2 a2)))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    real(8) :: t_1
    t_1 = cos(th) / sqrt(2.0d0)
    code = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
end function
public static double code(double a1, double a2, double th) {
	double t_1 = Math.cos(th) / Math.sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
def code(a1, a2, th):
	t_1 = math.cos(th) / math.sqrt(2.0)
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
function code(a1, a2, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	return Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2 * a2)))
end
function tmp = code(a1, a2, th)
	t_1 = cos(th) / sqrt(2.0);
	tmp = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right)
\end{array}
\end{array}

Alternative 1: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \mathsf{fma}\left(\cos th \cdot \frac{a2\_m}{\sqrt{2}}, a2\_m, \left(a1 \cdot \cos th\right) \cdot \frac{a1}{\sqrt{2}}\right) \end{array} \]
a2_m = (fabs.f64 a2)
NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
(FPCore (a1 a2_m th)
 :precision binary64
 (fma
  (* (cos th) (/ a2_m (sqrt 2.0)))
  a2_m
  (* (* a1 (cos th)) (/ a1 (sqrt 2.0)))))
a2_m = fabs(a2);
assert(a1 < a2_m && a2_m < th);
double code(double a1, double a2_m, double th) {
	return fma((cos(th) * (a2_m / sqrt(2.0))), a2_m, ((a1 * cos(th)) * (a1 / sqrt(2.0))));
}
a2_m = abs(a2)
a1, a2_m, th = sort([a1, a2_m, th])
function code(a1, a2_m, th)
	return fma(Float64(cos(th) * Float64(a2_m / sqrt(2.0))), a2_m, Float64(Float64(a1 * cos(th)) * Float64(a1 / sqrt(2.0))))
end
a2_m = N[Abs[a2], $MachinePrecision]
NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
code[a1_, a2$95$m_, th_] := N[(N[(N[Cos[th], $MachinePrecision] * N[(a2$95$m / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * a2$95$m + N[(N[(a1 * N[Cos[th], $MachinePrecision]), $MachinePrecision] * N[(a1 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
a2_m = \left|a2\right|
\\
[a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
\\
\mathsf{fma}\left(\cos th \cdot \frac{a2\_m}{\sqrt{2}}, a2\_m, \left(a1 \cdot \cos th\right) \cdot \frac{a1}{\sqrt{2}}\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
    2. +-commutativeN/A

      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} \]
    3. lift-*.f64N/A

      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) \]
    4. lift-*.f64N/A

      \[\leadsto \frac{\cos th}{\sqrt{2}} \cdot \color{blue}{\left(a2 \cdot a2\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) \]
    5. associate-*r*N/A

      \[\leadsto \color{blue}{\left(\frac{\cos th}{\sqrt{2}} \cdot a2\right) \cdot a2} + \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) \]
    6. lower-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{\cos th}{\sqrt{2}} \cdot a2, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right)} \]
    7. lift-/.f64N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot a2, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right) \]
    8. associate-*l/N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\cos th \cdot a2}{\sqrt{2}}}, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right) \]
    9. associate-/l*N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\cos th \cdot \frac{a2}{\sqrt{2}}}, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right) \]
    10. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\cos th \cdot \frac{a2}{\sqrt{2}}}, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right) \]
    11. lower-/.f6499.6

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \color{blue}{\frac{a2}{\sqrt{2}}}, a2, \frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)\right) \]
    12. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)}\right) \]
    13. lift-/.f64N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right)\right) \]
    14. associate-*l/N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}}\right) \]
    15. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \frac{\cos th \cdot \color{blue}{\left(a1 \cdot a1\right)}}{\sqrt{2}}\right) \]
    16. associate-*r*N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \frac{\color{blue}{\left(\cos th \cdot a1\right) \cdot a1}}{\sqrt{2}}\right) \]
    17. associate-/l*N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \color{blue}{\left(\cos th \cdot a1\right) \cdot \frac{a1}{\sqrt{2}}}\right) \]
    18. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \color{blue}{\left(\cos th \cdot a1\right) \cdot \frac{a1}{\sqrt{2}}}\right) \]
  4. Applied rewrites99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\cos th \cdot \frac{a2}{\sqrt{2}}, a2, \left(a1 \cdot \cos th\right) \cdot \frac{a1}{\sqrt{2}}\right)} \]
  5. Add Preprocessing

Alternative 2: 76.3% accurate, 0.8× speedup?

\[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2\_m \cdot a2\_m\right) \leq -5 \cdot 10^{-112}:\\ \;\;\;\;\left(\left(a2\_m \cdot th\right) \cdot th\right) \cdot \left(\frac{-0.5}{\sqrt{2}} \cdot a2\_m\right)\\ \mathbf{else}:\\ \;\;\;\;\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2}\\ \end{array} \end{array} \]
a2_m = (fabs.f64 a2)
NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
(FPCore (a1 a2_m th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (if (<= (+ (* t_1 (* a1 a1)) (* t_1 (* a2_m a2_m))) -5e-112)
     (* (* (* a2_m th) th) (* (/ -0.5 (sqrt 2.0)) a2_m))
     (* (* 0.5 (fma a1 a1 (* a2_m a2_m))) (sqrt 2.0)))))
a2_m = fabs(a2);
assert(a1 < a2_m && a2_m < th);
double code(double a1, double a2_m, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	double tmp;
	if (((t_1 * (a1 * a1)) + (t_1 * (a2_m * a2_m))) <= -5e-112) {
		tmp = ((a2_m * th) * th) * ((-0.5 / sqrt(2.0)) * a2_m);
	} else {
		tmp = (0.5 * fma(a1, a1, (a2_m * a2_m))) * sqrt(2.0);
	}
	return tmp;
}
a2_m = abs(a2)
a1, a2_m, th = sort([a1, a2_m, th])
function code(a1, a2_m, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	tmp = 0.0
	if (Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2_m * a2_m))) <= -5e-112)
		tmp = Float64(Float64(Float64(a2_m * th) * th) * Float64(Float64(-0.5 / sqrt(2.0)) * a2_m));
	else
		tmp = Float64(Float64(0.5 * fma(a1, a1, Float64(a2_m * a2_m))) * sqrt(2.0));
	end
	return tmp
end
a2_m = N[Abs[a2], $MachinePrecision]
NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
code[a1_, a2$95$m_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -5e-112], N[(N[(N[(a2$95$m * th), $MachinePrecision] * th), $MachinePrecision] * N[(N[(-0.5 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * a2$95$m), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[(a1 * a1 + N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
a2_m = \left|a2\right|
\\
[a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
\mathbf{if}\;t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2\_m \cdot a2\_m\right) \leq -5 \cdot 10^{-112}:\\
\;\;\;\;\left(\left(a2\_m \cdot th\right) \cdot th\right) \cdot \left(\frac{-0.5}{\sqrt{2}} \cdot a2\_m\right)\\

\mathbf{else}:\\
\;\;\;\;\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2))) < -5.00000000000000044e-112

    1. Initial program 99.5%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Taylor expanded in a1 around 0

      \[\leadsto \color{blue}{\frac{{a2}^{2} \cdot \cos th}{\sqrt{2}}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\cos th \cdot {a2}^{2}}}{\sqrt{2}} \]
      2. unpow2N/A

        \[\leadsto \frac{\cos th \cdot \color{blue}{\left(a2 \cdot a2\right)}}{\sqrt{2}} \]
      3. associate-*r*N/A

        \[\leadsto \frac{\color{blue}{\left(\cos th \cdot a2\right) \cdot a2}}{\sqrt{2}} \]
      4. associate-/l*N/A

        \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
      5. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
      6. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\cos th \cdot a2\right)} \cdot \frac{a2}{\sqrt{2}} \]
      7. lower-cos.f64N/A

        \[\leadsto \left(\color{blue}{\cos th} \cdot a2\right) \cdot \frac{a2}{\sqrt{2}} \]
      8. lower-/.f64N/A

        \[\leadsto \left(\cos th \cdot a2\right) \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
      9. lower-sqrt.f6471.3

        \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
    5. Applied rewrites71.3%

      \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
    6. Taylor expanded in th around 0

      \[\leadsto \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} + \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}} \]
    7. Step-by-step derivation
      1. Applied rewrites14.1%

        \[\leadsto \frac{\mathsf{fma}\left(\left(\left(th \cdot th\right) \cdot a2\right) \cdot a2, -0.5, a2 \cdot a2\right)}{\color{blue}{\sqrt{2}}} \]
      2. Taylor expanded in th around inf

        \[\leadsto \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\color{blue}{\sqrt{2}}} \]
      3. Step-by-step derivation
        1. Applied rewrites43.6%

          \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \frac{-0.5}{\sqrt{2}}\right) \cdot \left(th \cdot \color{blue}{th}\right) \]
        2. Step-by-step derivation
          1. Applied rewrites44.0%

            \[\leadsto \left(\left(a2 \cdot th\right) \cdot th\right) \cdot \left(\frac{-0.5}{\sqrt{2}} \cdot a2\right) \]

          if -5.00000000000000044e-112 < (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2)))

          1. Initial program 99.6%

            \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-+.f64N/A

              \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
            2. lift-*.f64N/A

              \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
            3. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
            4. associate-*l/N/A

              \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
            5. lift-*.f64N/A

              \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
            6. lift-/.f64N/A

              \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
            7. associate-*l/N/A

              \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
            8. frac-addN/A

              \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
            9. lift-sqrt.f64N/A

              \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
            10. lift-sqrt.f64N/A

              \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
            11. rem-square-sqrtN/A

              \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
            12. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
          4. Applied rewrites99.6%

            \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
          5. Taylor expanded in a1 around 0

            \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) + \frac{1}{2} \cdot \left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
          6. Step-by-step derivation
            1. distribute-lft-inN/A

              \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right) + {a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
            2. distribute-rgt-outN/A

              \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\cos th \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
            3. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
            4. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
            5. *-commutativeN/A

              \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            6. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            7. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            8. lower-*.f64N/A

              \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            9. lower-sqrt.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            10. lower-cos.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \color{blue}{\cos th}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
            11. unpow2N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right) \]
            12. lower-fma.f64N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)} \]
            13. unpow2N/A

              \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
            14. lower-*.f6499.6

              \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
          7. Applied rewrites99.6%

            \[\leadsto \color{blue}{\left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)} \]
          8. Taylor expanded in th around 0

            \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \]
          9. Step-by-step derivation
            1. distribute-rgt-inN/A

              \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
            2. *-commutativeN/A

              \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left({a1}^{2} + {a2}^{2}\right) \cdot \sqrt{2}\right)} \]
            3. associate-*r*N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
            4. metadata-evalN/A

              \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
            5. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
            6. metadata-evalN/A

              \[\leadsto \left(\color{blue}{\frac{1}{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
            7. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \sqrt{2} \]
            8. unpow2N/A

              \[\leadsto \left(\frac{1}{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
            9. lower-fma.f64N/A

              \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \sqrt{2} \]
            10. unpow2N/A

              \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
            11. lower-*.f64N/A

              \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
            12. lower-sqrt.f6483.4

              \[\leadsto \left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \color{blue}{\sqrt{2}} \]
          10. Applied rewrites83.4%

            \[\leadsto \color{blue}{\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \sqrt{2}} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 3: 76.6% accurate, 0.8× speedup?

        \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2\_m \cdot a2\_m\right) \leq -5 \cdot 10^{-112}:\\ \;\;\;\;a2\_m \cdot \left(a2\_m \cdot \left(\left(\frac{-0.5}{\sqrt{2}} \cdot th\right) \cdot th\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2}\\ \end{array} \end{array} \]
        a2_m = (fabs.f64 a2)
        NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
        (FPCore (a1 a2_m th)
         :precision binary64
         (let* ((t_1 (/ (cos th) (sqrt 2.0))))
           (if (<= (+ (* t_1 (* a1 a1)) (* t_1 (* a2_m a2_m))) -5e-112)
             (* a2_m (* a2_m (* (* (/ -0.5 (sqrt 2.0)) th) th)))
             (* (* 0.5 (fma a1 a1 (* a2_m a2_m))) (sqrt 2.0)))))
        a2_m = fabs(a2);
        assert(a1 < a2_m && a2_m < th);
        double code(double a1, double a2_m, double th) {
        	double t_1 = cos(th) / sqrt(2.0);
        	double tmp;
        	if (((t_1 * (a1 * a1)) + (t_1 * (a2_m * a2_m))) <= -5e-112) {
        		tmp = a2_m * (a2_m * (((-0.5 / sqrt(2.0)) * th) * th));
        	} else {
        		tmp = (0.5 * fma(a1, a1, (a2_m * a2_m))) * sqrt(2.0);
        	}
        	return tmp;
        }
        
        a2_m = abs(a2)
        a1, a2_m, th = sort([a1, a2_m, th])
        function code(a1, a2_m, th)
        	t_1 = Float64(cos(th) / sqrt(2.0))
        	tmp = 0.0
        	if (Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2_m * a2_m))) <= -5e-112)
        		tmp = Float64(a2_m * Float64(a2_m * Float64(Float64(Float64(-0.5 / sqrt(2.0)) * th) * th)));
        	else
        		tmp = Float64(Float64(0.5 * fma(a1, a1, Float64(a2_m * a2_m))) * sqrt(2.0));
        	end
        	return tmp
        end
        
        a2_m = N[Abs[a2], $MachinePrecision]
        NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
        code[a1_, a2$95$m_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -5e-112], N[(a2$95$m * N[(a2$95$m * N[(N[(N[(-0.5 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * th), $MachinePrecision] * th), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[(a1 * a1 + N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]]]
        
        \begin{array}{l}
        a2_m = \left|a2\right|
        \\
        [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
        \\
        \begin{array}{l}
        t_1 := \frac{\cos th}{\sqrt{2}}\\
        \mathbf{if}\;t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2\_m \cdot a2\_m\right) \leq -5 \cdot 10^{-112}:\\
        \;\;\;\;a2\_m \cdot \left(a2\_m \cdot \left(\left(\frac{-0.5}{\sqrt{2}} \cdot th\right) \cdot th\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2))) < -5.00000000000000044e-112

          1. Initial program 99.5%

            \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
          2. Add Preprocessing
          3. Taylor expanded in a1 around 0

            \[\leadsto \color{blue}{\frac{{a2}^{2} \cdot \cos th}{\sqrt{2}}} \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto \frac{\color{blue}{\cos th \cdot {a2}^{2}}}{\sqrt{2}} \]
            2. unpow2N/A

              \[\leadsto \frac{\cos th \cdot \color{blue}{\left(a2 \cdot a2\right)}}{\sqrt{2}} \]
            3. associate-*r*N/A

              \[\leadsto \frac{\color{blue}{\left(\cos th \cdot a2\right) \cdot a2}}{\sqrt{2}} \]
            4. associate-/l*N/A

              \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
            5. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
            6. lower-*.f64N/A

              \[\leadsto \color{blue}{\left(\cos th \cdot a2\right)} \cdot \frac{a2}{\sqrt{2}} \]
            7. lower-cos.f64N/A

              \[\leadsto \left(\color{blue}{\cos th} \cdot a2\right) \cdot \frac{a2}{\sqrt{2}} \]
            8. lower-/.f64N/A

              \[\leadsto \left(\cos th \cdot a2\right) \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
            9. lower-sqrt.f6471.3

              \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
          5. Applied rewrites71.3%

            \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
          6. Taylor expanded in th around 0

            \[\leadsto \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} + \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}} \]
          7. Step-by-step derivation
            1. Applied rewrites14.1%

              \[\leadsto \frac{\mathsf{fma}\left(\left(\left(th \cdot th\right) \cdot a2\right) \cdot a2, -0.5, a2 \cdot a2\right)}{\color{blue}{\sqrt{2}}} \]
            2. Taylor expanded in th around inf

              \[\leadsto \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\color{blue}{\sqrt{2}}} \]
            3. Step-by-step derivation
              1. Applied rewrites43.6%

                \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \frac{-0.5}{\sqrt{2}}\right) \cdot \left(th \cdot \color{blue}{th}\right) \]
              2. Step-by-step derivation
                1. Applied rewrites46.0%

                  \[\leadsto a2 \cdot \left(a2 \cdot \left(\left(\frac{-0.5}{\sqrt{2}} \cdot th\right) \cdot \color{blue}{th}\right)\right) \]

                if -5.00000000000000044e-112 < (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2)))

                1. Initial program 99.6%

                  \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift-+.f64N/A

                    \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                  2. lift-*.f64N/A

                    \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  3. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  4. associate-*l/N/A

                    \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  5. lift-*.f64N/A

                    \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                  6. lift-/.f64N/A

                    \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
                  7. associate-*l/N/A

                    \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
                  8. frac-addN/A

                    \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
                  9. lift-sqrt.f64N/A

                    \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
                  10. lift-sqrt.f64N/A

                    \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
                  11. rem-square-sqrtN/A

                    \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
                  12. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
                4. Applied rewrites99.6%

                  \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
                5. Taylor expanded in a1 around 0

                  \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) + \frac{1}{2} \cdot \left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                6. Step-by-step derivation
                  1. distribute-lft-inN/A

                    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right) + {a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                  2. distribute-rgt-outN/A

                    \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\cos th \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                  3. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                  4. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                  5. *-commutativeN/A

                    \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  6. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  7. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  8. lower-*.f64N/A

                    \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  9. lower-sqrt.f64N/A

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  10. lower-cos.f64N/A

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \color{blue}{\cos th}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                  11. unpow2N/A

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right) \]
                  12. lower-fma.f64N/A

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)} \]
                  13. unpow2N/A

                    \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                  14. lower-*.f6499.6

                    \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                7. Applied rewrites99.6%

                  \[\leadsto \color{blue}{\left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)} \]
                8. Taylor expanded in th around 0

                  \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \]
                9. Step-by-step derivation
                  1. distribute-rgt-inN/A

                    \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                  2. *-commutativeN/A

                    \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left({a1}^{2} + {a2}^{2}\right) \cdot \sqrt{2}\right)} \]
                  3. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
                  4. metadata-evalN/A

                    \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                  5. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
                  6. metadata-evalN/A

                    \[\leadsto \left(\color{blue}{\frac{1}{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                  7. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \sqrt{2} \]
                  8. unpow2N/A

                    \[\leadsto \left(\frac{1}{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                  9. lower-fma.f64N/A

                    \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \sqrt{2} \]
                  10. unpow2N/A

                    \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
                  11. lower-*.f64N/A

                    \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
                  12. lower-sqrt.f6483.4

                    \[\leadsto \left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \color{blue}{\sqrt{2}} \]
                10. Applied rewrites83.4%

                  \[\leadsto \color{blue}{\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \sqrt{2}} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 4: 99.6% accurate, 1.9× speedup?

              \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right) \end{array} \]
              a2_m = (fabs.f64 a2)
              NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
              (FPCore (a1 a2_m th)
               :precision binary64
               (* (* (* 0.5 (sqrt 2.0)) (cos th)) (fma a1 a1 (* a2_m a2_m))))
              a2_m = fabs(a2);
              assert(a1 < a2_m && a2_m < th);
              double code(double a1, double a2_m, double th) {
              	return ((0.5 * sqrt(2.0)) * cos(th)) * fma(a1, a1, (a2_m * a2_m));
              }
              
              a2_m = abs(a2)
              a1, a2_m, th = sort([a1, a2_m, th])
              function code(a1, a2_m, th)
              	return Float64(Float64(Float64(0.5 * sqrt(2.0)) * cos(th)) * fma(a1, a1, Float64(a2_m * a2_m)))
              end
              
              a2_m = N[Abs[a2], $MachinePrecision]
              NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
              code[a1_, a2$95$m_, th_] := N[(N[(N[(0.5 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision] * N[(a1 * a1 + N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              a2_m = \left|a2\right|
              \\
              [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
              \\
              \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)
              \end{array}
              
              Derivation
              1. Initial program 99.5%

                \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-+.f64N/A

                  \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                2. lift-*.f64N/A

                  \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                3. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                4. associate-*l/N/A

                  \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                5. lift-*.f64N/A

                  \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                6. lift-/.f64N/A

                  \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
                7. associate-*l/N/A

                  \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
                8. frac-addN/A

                  \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
                9. lift-sqrt.f64N/A

                  \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
                10. lift-sqrt.f64N/A

                  \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
                11. rem-square-sqrtN/A

                  \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
                12. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
              4. Applied rewrites99.6%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
              5. Taylor expanded in a1 around 0

                \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) + \frac{1}{2} \cdot \left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
              6. Step-by-step derivation
                1. distribute-lft-inN/A

                  \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right) + {a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                2. distribute-rgt-outN/A

                  \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\cos th \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                3. associate-*r*N/A

                  \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                4. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                5. *-commutativeN/A

                  \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                6. associate-*r*N/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                7. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                8. lower-*.f64N/A

                  \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                9. lower-sqrt.f64N/A

                  \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                10. lower-cos.f64N/A

                  \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \color{blue}{\cos th}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                11. unpow2N/A

                  \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right) \]
                12. lower-fma.f64N/A

                  \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)} \]
                13. unpow2N/A

                  \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                14. lower-*.f6499.6

                  \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
              7. Applied rewrites99.6%

                \[\leadsto \color{blue}{\left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)} \]
              8. Add Preprocessing

              Alternative 5: 78.8% accurate, 1.9× speedup?

              \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(\cos th \cdot a2\_m\right) \cdot \sqrt{\frac{a2\_m \cdot a2\_m}{2}} \end{array} \]
              a2_m = (fabs.f64 a2)
              NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
              (FPCore (a1 a2_m th)
               :precision binary64
               (* (* (cos th) a2_m) (sqrt (/ (* a2_m a2_m) 2.0))))
              a2_m = fabs(a2);
              assert(a1 < a2_m && a2_m < th);
              double code(double a1, double a2_m, double th) {
              	return (cos(th) * a2_m) * sqrt(((a2_m * a2_m) / 2.0));
              }
              
              a2_m = abs(a2)
              NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
              real(8) function code(a1, a2_m, th)
                  real(8), intent (in) :: a1
                  real(8), intent (in) :: a2_m
                  real(8), intent (in) :: th
                  code = (cos(th) * a2_m) * sqrt(((a2_m * a2_m) / 2.0d0))
              end function
              
              a2_m = Math.abs(a2);
              assert a1 < a2_m && a2_m < th;
              public static double code(double a1, double a2_m, double th) {
              	return (Math.cos(th) * a2_m) * Math.sqrt(((a2_m * a2_m) / 2.0));
              }
              
              a2_m = math.fabs(a2)
              [a1, a2_m, th] = sort([a1, a2_m, th])
              def code(a1, a2_m, th):
              	return (math.cos(th) * a2_m) * math.sqrt(((a2_m * a2_m) / 2.0))
              
              a2_m = abs(a2)
              a1, a2_m, th = sort([a1, a2_m, th])
              function code(a1, a2_m, th)
              	return Float64(Float64(cos(th) * a2_m) * sqrt(Float64(Float64(a2_m * a2_m) / 2.0)))
              end
              
              a2_m = abs(a2);
              a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
              function tmp = code(a1, a2_m, th)
              	tmp = (cos(th) * a2_m) * sqrt(((a2_m * a2_m) / 2.0));
              end
              
              a2_m = N[Abs[a2], $MachinePrecision]
              NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
              code[a1_, a2$95$m_, th_] := N[(N[(N[Cos[th], $MachinePrecision] * a2$95$m), $MachinePrecision] * N[Sqrt[N[(N[(a2$95$m * a2$95$m), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              a2_m = \left|a2\right|
              \\
              [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
              \\
              \left(\cos th \cdot a2\_m\right) \cdot \sqrt{\frac{a2\_m \cdot a2\_m}{2}}
              \end{array}
              
              Derivation
              1. Initial program 99.5%

                \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
              2. Add Preprocessing
              3. Taylor expanded in a1 around 0

                \[\leadsto \color{blue}{\frac{{a2}^{2} \cdot \cos th}{\sqrt{2}}} \]
              4. Step-by-step derivation
                1. *-commutativeN/A

                  \[\leadsto \frac{\color{blue}{\cos th \cdot {a2}^{2}}}{\sqrt{2}} \]
                2. unpow2N/A

                  \[\leadsto \frac{\cos th \cdot \color{blue}{\left(a2 \cdot a2\right)}}{\sqrt{2}} \]
                3. associate-*r*N/A

                  \[\leadsto \frac{\color{blue}{\left(\cos th \cdot a2\right) \cdot a2}}{\sqrt{2}} \]
                4. associate-/l*N/A

                  \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
                5. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
                6. lower-*.f64N/A

                  \[\leadsto \color{blue}{\left(\cos th \cdot a2\right)} \cdot \frac{a2}{\sqrt{2}} \]
                7. lower-cos.f64N/A

                  \[\leadsto \left(\color{blue}{\cos th} \cdot a2\right) \cdot \frac{a2}{\sqrt{2}} \]
                8. lower-/.f64N/A

                  \[\leadsto \left(\cos th \cdot a2\right) \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
                9. lower-sqrt.f6456.6

                  \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
              5. Applied rewrites56.6%

                \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
              6. Step-by-step derivation
                1. Applied rewrites34.3%

                  \[\leadsto \left(\cos th \cdot a2\right) \cdot \sqrt{\frac{a2 \cdot a2}{2}} \]
                2. Add Preprocessing

                Alternative 6: 78.8% accurate, 2.0× speedup?

                \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(\frac{a2\_m}{\sqrt{2}} \cdot \cos th\right) \cdot a2\_m \end{array} \]
                a2_m = (fabs.f64 a2)
                NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                (FPCore (a1 a2_m th)
                 :precision binary64
                 (* (* (/ a2_m (sqrt 2.0)) (cos th)) a2_m))
                a2_m = fabs(a2);
                assert(a1 < a2_m && a2_m < th);
                double code(double a1, double a2_m, double th) {
                	return ((a2_m / sqrt(2.0)) * cos(th)) * a2_m;
                }
                
                a2_m = abs(a2)
                NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                real(8) function code(a1, a2_m, th)
                    real(8), intent (in) :: a1
                    real(8), intent (in) :: a2_m
                    real(8), intent (in) :: th
                    code = ((a2_m / sqrt(2.0d0)) * cos(th)) * a2_m
                end function
                
                a2_m = Math.abs(a2);
                assert a1 < a2_m && a2_m < th;
                public static double code(double a1, double a2_m, double th) {
                	return ((a2_m / Math.sqrt(2.0)) * Math.cos(th)) * a2_m;
                }
                
                a2_m = math.fabs(a2)
                [a1, a2_m, th] = sort([a1, a2_m, th])
                def code(a1, a2_m, th):
                	return ((a2_m / math.sqrt(2.0)) * math.cos(th)) * a2_m
                
                a2_m = abs(a2)
                a1, a2_m, th = sort([a1, a2_m, th])
                function code(a1, a2_m, th)
                	return Float64(Float64(Float64(a2_m / sqrt(2.0)) * cos(th)) * a2_m)
                end
                
                a2_m = abs(a2);
                a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
                function tmp = code(a1, a2_m, th)
                	tmp = ((a2_m / sqrt(2.0)) * cos(th)) * a2_m;
                end
                
                a2_m = N[Abs[a2], $MachinePrecision]
                NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                code[a1_, a2$95$m_, th_] := N[(N[(N[(a2$95$m / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision] * a2$95$m), $MachinePrecision]
                
                \begin{array}{l}
                a2_m = \left|a2\right|
                \\
                [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                \\
                \left(\frac{a2\_m}{\sqrt{2}} \cdot \cos th\right) \cdot a2\_m
                \end{array}
                
                Derivation
                1. Initial program 99.5%

                  \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                2. Add Preprocessing
                3. Taylor expanded in a1 around 0

                  \[\leadsto \color{blue}{\frac{{a2}^{2} \cdot \cos th}{\sqrt{2}}} \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \frac{\color{blue}{\cos th \cdot {a2}^{2}}}{\sqrt{2}} \]
                  2. unpow2N/A

                    \[\leadsto \frac{\cos th \cdot \color{blue}{\left(a2 \cdot a2\right)}}{\sqrt{2}} \]
                  3. associate-*r*N/A

                    \[\leadsto \frac{\color{blue}{\left(\cos th \cdot a2\right) \cdot a2}}{\sqrt{2}} \]
                  4. associate-/l*N/A

                    \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
                  5. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
                  6. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\cos th \cdot a2\right)} \cdot \frac{a2}{\sqrt{2}} \]
                  7. lower-cos.f64N/A

                    \[\leadsto \left(\color{blue}{\cos th} \cdot a2\right) \cdot \frac{a2}{\sqrt{2}} \]
                  8. lower-/.f64N/A

                    \[\leadsto \left(\cos th \cdot a2\right) \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
                  9. lower-sqrt.f6456.6

                    \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
                5. Applied rewrites56.6%

                  \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
                6. Step-by-step derivation
                  1. Applied rewrites56.6%

                    \[\leadsto \left(\frac{a2}{\sqrt{2}} \cdot \cos th\right) \cdot \color{blue}{a2} \]
                  2. Add Preprocessing

                  Alternative 7: 78.8% accurate, 2.0× speedup?

                  \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(0.5 \cdot \left(a2\_m \cdot a2\_m\right)\right) \cdot \left(\sqrt{2} \cdot \cos th\right) \end{array} \]
                  a2_m = (fabs.f64 a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  (FPCore (a1 a2_m th)
                   :precision binary64
                   (* (* 0.5 (* a2_m a2_m)) (* (sqrt 2.0) (cos th))))
                  a2_m = fabs(a2);
                  assert(a1 < a2_m && a2_m < th);
                  double code(double a1, double a2_m, double th) {
                  	return (0.5 * (a2_m * a2_m)) * (sqrt(2.0) * cos(th));
                  }
                  
                  a2_m = abs(a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  real(8) function code(a1, a2_m, th)
                      real(8), intent (in) :: a1
                      real(8), intent (in) :: a2_m
                      real(8), intent (in) :: th
                      code = (0.5d0 * (a2_m * a2_m)) * (sqrt(2.0d0) * cos(th))
                  end function
                  
                  a2_m = Math.abs(a2);
                  assert a1 < a2_m && a2_m < th;
                  public static double code(double a1, double a2_m, double th) {
                  	return (0.5 * (a2_m * a2_m)) * (Math.sqrt(2.0) * Math.cos(th));
                  }
                  
                  a2_m = math.fabs(a2)
                  [a1, a2_m, th] = sort([a1, a2_m, th])
                  def code(a1, a2_m, th):
                  	return (0.5 * (a2_m * a2_m)) * (math.sqrt(2.0) * math.cos(th))
                  
                  a2_m = abs(a2)
                  a1, a2_m, th = sort([a1, a2_m, th])
                  function code(a1, a2_m, th)
                  	return Float64(Float64(0.5 * Float64(a2_m * a2_m)) * Float64(sqrt(2.0) * cos(th)))
                  end
                  
                  a2_m = abs(a2);
                  a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
                  function tmp = code(a1, a2_m, th)
                  	tmp = (0.5 * (a2_m * a2_m)) * (sqrt(2.0) * cos(th));
                  end
                  
                  a2_m = N[Abs[a2], $MachinePrecision]
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  code[a1_, a2$95$m_, th_] := N[(N[(0.5 * N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  a2_m = \left|a2\right|
                  \\
                  [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                  \\
                  \left(0.5 \cdot \left(a2\_m \cdot a2\_m\right)\right) \cdot \left(\sqrt{2} \cdot \cos th\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.5%

                    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. lift-+.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    2. lift-*.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    3. lift-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    4. associate-*l/N/A

                      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    5. lift-*.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    6. lift-/.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
                    7. associate-*l/N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
                    8. frac-addN/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
                    9. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
                    10. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
                    11. rem-square-sqrtN/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
                    12. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
                  4. Applied rewrites99.6%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
                  5. Taylor expanded in a1 around 0

                    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                  6. Step-by-step derivation
                    1. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {a2}^{2}\right) \cdot \left(\cos th \cdot \sqrt{2}\right)} \]
                    2. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {a2}^{2}\right) \cdot \left(\cos th \cdot \sqrt{2}\right)} \]
                    3. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot {a2}^{2}\right)} \cdot \left(\cos th \cdot \sqrt{2}\right) \]
                    4. unpow2N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(a2 \cdot a2\right)}\right) \cdot \left(\cos th \cdot \sqrt{2}\right) \]
                    5. lower-*.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(a2 \cdot a2\right)}\right) \cdot \left(\cos th \cdot \sqrt{2}\right) \]
                    6. *-commutativeN/A

                      \[\leadsto \left(\frac{1}{2} \cdot \left(a2 \cdot a2\right)\right) \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)} \]
                    7. lower-*.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \left(a2 \cdot a2\right)\right) \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)} \]
                    8. lower-sqrt.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \left(a2 \cdot a2\right)\right) \cdot \left(\color{blue}{\sqrt{2}} \cdot \cos th\right) \]
                    9. lower-cos.f6456.6

                      \[\leadsto \left(0.5 \cdot \left(a2 \cdot a2\right)\right) \cdot \left(\sqrt{2} \cdot \color{blue}{\cos th}\right) \]
                  7. Applied rewrites56.6%

                    \[\leadsto \color{blue}{\left(0.5 \cdot \left(a2 \cdot a2\right)\right) \cdot \left(\sqrt{2} \cdot \cos th\right)} \]
                  8. Add Preprocessing

                  Alternative 8: 66.4% accurate, 8.3× speedup?

                  \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2} \end{array} \]
                  a2_m = (fabs.f64 a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  (FPCore (a1 a2_m th)
                   :precision binary64
                   (* (* 0.5 (fma a1 a1 (* a2_m a2_m))) (sqrt 2.0)))
                  a2_m = fabs(a2);
                  assert(a1 < a2_m && a2_m < th);
                  double code(double a1, double a2_m, double th) {
                  	return (0.5 * fma(a1, a1, (a2_m * a2_m))) * sqrt(2.0);
                  }
                  
                  a2_m = abs(a2)
                  a1, a2_m, th = sort([a1, a2_m, th])
                  function code(a1, a2_m, th)
                  	return Float64(Float64(0.5 * fma(a1, a1, Float64(a2_m * a2_m))) * sqrt(2.0))
                  end
                  
                  a2_m = N[Abs[a2], $MachinePrecision]
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  code[a1_, a2$95$m_, th_] := N[(N[(0.5 * N[(a1 * a1 + N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  a2_m = \left|a2\right|
                  \\
                  [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                  \\
                  \left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)\right) \cdot \sqrt{2}
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.5%

                    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. lift-+.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    2. lift-*.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    3. lift-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    4. associate-*l/N/A

                      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    5. lift-*.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    6. lift-/.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
                    7. associate-*l/N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
                    8. frac-addN/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
                    9. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
                    10. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
                    11. rem-square-sqrtN/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
                    12. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
                  4. Applied rewrites99.6%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
                  5. Taylor expanded in a1 around 0

                    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) + \frac{1}{2} \cdot \left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                  6. Step-by-step derivation
                    1. distribute-lft-inN/A

                      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right) + {a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \]
                    2. distribute-rgt-outN/A

                      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\cos th \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                    3. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                    4. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                    5. *-commutativeN/A

                      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    6. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    7. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    8. lower-*.f64N/A

                      \[\leadsto \left(\color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    9. lower-sqrt.f64N/A

                      \[\leadsto \left(\left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \cdot \cos th\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    10. lower-cos.f64N/A

                      \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \color{blue}{\cos th}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    11. unpow2N/A

                      \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right) \]
                    12. lower-fma.f64N/A

                      \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)} \]
                    13. unpow2N/A

                      \[\leadsto \left(\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                    14. lower-*.f6499.6

                      \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                  7. Applied rewrites99.6%

                    \[\leadsto \color{blue}{\left(\left(0.5 \cdot \sqrt{2}\right) \cdot \cos th\right) \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)} \]
                  8. Taylor expanded in th around 0

                    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \]
                  9. Step-by-step derivation
                    1. distribute-rgt-inN/A

                      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                    2. *-commutativeN/A

                      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left({a1}^{2} + {a2}^{2}\right) \cdot \sqrt{2}\right)} \]
                    3. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
                    4. metadata-evalN/A

                      \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                    5. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right) \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2}} \]
                    6. metadata-evalN/A

                      \[\leadsto \left(\color{blue}{\frac{1}{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                    7. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \sqrt{2} \]
                    8. unpow2N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \sqrt{2} \]
                    9. lower-fma.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \sqrt{2} \]
                    10. unpow2N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
                    11. lower-*.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \sqrt{2} \]
                    12. lower-sqrt.f6469.2

                      \[\leadsto \left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \color{blue}{\sqrt{2}} \]
                  10. Applied rewrites69.2%

                    \[\leadsto \color{blue}{\left(0.5 \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \sqrt{2}} \]
                  11. Add Preprocessing

                  Alternative 9: 66.4% accurate, 8.3× speedup?

                  \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ \left(0.5 \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right) \end{array} \]
                  a2_m = (fabs.f64 a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  (FPCore (a1 a2_m th)
                   :precision binary64
                   (* (* 0.5 (sqrt 2.0)) (fma a1 a1 (* a2_m a2_m))))
                  a2_m = fabs(a2);
                  assert(a1 < a2_m && a2_m < th);
                  double code(double a1, double a2_m, double th) {
                  	return (0.5 * sqrt(2.0)) * fma(a1, a1, (a2_m * a2_m));
                  }
                  
                  a2_m = abs(a2)
                  a1, a2_m, th = sort([a1, a2_m, th])
                  function code(a1, a2_m, th)
                  	return Float64(Float64(0.5 * sqrt(2.0)) * fma(a1, a1, Float64(a2_m * a2_m)))
                  end
                  
                  a2_m = N[Abs[a2], $MachinePrecision]
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  code[a1_, a2$95$m_, th_] := N[(N[(0.5 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[(a1 * a1 + N[(a2$95$m * a2$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  a2_m = \left|a2\right|
                  \\
                  [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                  \\
                  \left(0.5 \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(a1, a1, a2\_m \cdot a2\_m\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.5%

                    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. lift-+.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    2. lift-*.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right)} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    3. lift-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    4. associate-*l/N/A

                      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                    5. lift-*.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)} \]
                    6. lift-/.f64N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th}{\sqrt{2}}} \cdot \left(a2 \cdot a2\right) \]
                    7. associate-*l/N/A

                      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
                    8. frac-addN/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
                    9. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{\sqrt{2}} \cdot \sqrt{2}} \]
                    10. lift-sqrt.f64N/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \color{blue}{\sqrt{2}}} \]
                    11. rem-square-sqrtN/A

                      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
                    12. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{2}} \]
                  4. Applied rewrites99.6%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2 \cdot \cos th, a2 \cdot \sqrt{2}, \left(a1 \cdot \cos th\right) \cdot \left(a1 \cdot \sqrt{2}\right)\right)}{2}} \]
                  5. Taylor expanded in th around 0

                    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \]
                  6. Step-by-step derivation
                    1. distribute-rgt-outN/A

                      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
                    2. associate-*r*N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                    3. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \left({a1}^{2} + {a2}^{2}\right)} \]
                    4. lower-*.f64N/A

                      \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    5. lower-sqrt.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \cdot \left({a1}^{2} + {a2}^{2}\right) \]
                    6. unpow2N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right) \]
                    7. lower-fma.f64N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)} \]
                    8. unpow2N/A

                      \[\leadsto \left(\frac{1}{2} \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                    9. lower-*.f6469.2

                      \[\leadsto \left(0.5 \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right) \]
                  7. Applied rewrites69.2%

                    \[\leadsto \color{blue}{\left(0.5 \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)} \]
                  8. Add Preprocessing

                  Alternative 10: 53.4% accurate, 8.3× speedup?

                  \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ a2\_m \cdot \sqrt{\frac{a2\_m \cdot a2\_m}{2}} \end{array} \]
                  a2_m = (fabs.f64 a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  (FPCore (a1 a2_m th) :precision binary64 (* a2_m (sqrt (/ (* a2_m a2_m) 2.0))))
                  a2_m = fabs(a2);
                  assert(a1 < a2_m && a2_m < th);
                  double code(double a1, double a2_m, double th) {
                  	return a2_m * sqrt(((a2_m * a2_m) / 2.0));
                  }
                  
                  a2_m = abs(a2)
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  real(8) function code(a1, a2_m, th)
                      real(8), intent (in) :: a1
                      real(8), intent (in) :: a2_m
                      real(8), intent (in) :: th
                      code = a2_m * sqrt(((a2_m * a2_m) / 2.0d0))
                  end function
                  
                  a2_m = Math.abs(a2);
                  assert a1 < a2_m && a2_m < th;
                  public static double code(double a1, double a2_m, double th) {
                  	return a2_m * Math.sqrt(((a2_m * a2_m) / 2.0));
                  }
                  
                  a2_m = math.fabs(a2)
                  [a1, a2_m, th] = sort([a1, a2_m, th])
                  def code(a1, a2_m, th):
                  	return a2_m * math.sqrt(((a2_m * a2_m) / 2.0))
                  
                  a2_m = abs(a2)
                  a1, a2_m, th = sort([a1, a2_m, th])
                  function code(a1, a2_m, th)
                  	return Float64(a2_m * sqrt(Float64(Float64(a2_m * a2_m) / 2.0)))
                  end
                  
                  a2_m = abs(a2);
                  a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
                  function tmp = code(a1, a2_m, th)
                  	tmp = a2_m * sqrt(((a2_m * a2_m) / 2.0));
                  end
                  
                  a2_m = N[Abs[a2], $MachinePrecision]
                  NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                  code[a1_, a2$95$m_, th_] := N[(a2$95$m * N[Sqrt[N[(N[(a2$95$m * a2$95$m), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  a2_m = \left|a2\right|
                  \\
                  [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                  \\
                  a2\_m \cdot \sqrt{\frac{a2\_m \cdot a2\_m}{2}}
                  \end{array}
                  
                  Derivation
                  1. Initial program 99.5%

                    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                  2. Add Preprocessing
                  3. Taylor expanded in th around 0

                    \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
                  4. Step-by-step derivation
                    1. div-add-revN/A

                      \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                    2. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                    3. +-commutativeN/A

                      \[\leadsto \frac{\color{blue}{{a2}^{2} + {a1}^{2}}}{\sqrt{2}} \]
                    4. unpow2N/A

                      \[\leadsto \frac{\color{blue}{a2 \cdot a2} + {a1}^{2}}{\sqrt{2}} \]
                    5. lower-fma.f64N/A

                      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(a2, a2, {a1}^{2}\right)}}{\sqrt{2}} \]
                    6. unpow2N/A

                      \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                    7. lower-*.f64N/A

                      \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                    8. lower-sqrt.f6469.2

                      \[\leadsto \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\color{blue}{\sqrt{2}}} \]
                  5. Applied rewrites69.2%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\sqrt{2}}} \]
                  6. Taylor expanded in a1 around 0

                    \[\leadsto \frac{{a2}^{2}}{\color{blue}{\sqrt{2}}} \]
                  7. Step-by-step derivation
                    1. Applied rewrites39.1%

                      \[\leadsto a2 \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
                    2. Step-by-step derivation
                      1. Applied rewrites28.2%

                        \[\leadsto a2 \cdot \sqrt{\frac{a2 \cdot a2}{2}} \]
                      2. Add Preprocessing

                      Alternative 11: 53.4% accurate, 9.9× speedup?

                      \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ a2\_m \cdot \frac{a2\_m}{\sqrt{2}} \end{array} \]
                      a2_m = (fabs.f64 a2)
                      NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                      (FPCore (a1 a2_m th) :precision binary64 (* a2_m (/ a2_m (sqrt 2.0))))
                      a2_m = fabs(a2);
                      assert(a1 < a2_m && a2_m < th);
                      double code(double a1, double a2_m, double th) {
                      	return a2_m * (a2_m / sqrt(2.0));
                      }
                      
                      a2_m = abs(a2)
                      NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                      real(8) function code(a1, a2_m, th)
                          real(8), intent (in) :: a1
                          real(8), intent (in) :: a2_m
                          real(8), intent (in) :: th
                          code = a2_m * (a2_m / sqrt(2.0d0))
                      end function
                      
                      a2_m = Math.abs(a2);
                      assert a1 < a2_m && a2_m < th;
                      public static double code(double a1, double a2_m, double th) {
                      	return a2_m * (a2_m / Math.sqrt(2.0));
                      }
                      
                      a2_m = math.fabs(a2)
                      [a1, a2_m, th] = sort([a1, a2_m, th])
                      def code(a1, a2_m, th):
                      	return a2_m * (a2_m / math.sqrt(2.0))
                      
                      a2_m = abs(a2)
                      a1, a2_m, th = sort([a1, a2_m, th])
                      function code(a1, a2_m, th)
                      	return Float64(a2_m * Float64(a2_m / sqrt(2.0)))
                      end
                      
                      a2_m = abs(a2);
                      a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
                      function tmp = code(a1, a2_m, th)
                      	tmp = a2_m * (a2_m / sqrt(2.0));
                      end
                      
                      a2_m = N[Abs[a2], $MachinePrecision]
                      NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                      code[a1_, a2$95$m_, th_] := N[(a2$95$m * N[(a2$95$m / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                      
                      \begin{array}{l}
                      a2_m = \left|a2\right|
                      \\
                      [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                      \\
                      a2\_m \cdot \frac{a2\_m}{\sqrt{2}}
                      \end{array}
                      
                      Derivation
                      1. Initial program 99.5%

                        \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                      2. Add Preprocessing
                      3. Taylor expanded in th around 0

                        \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
                      4. Step-by-step derivation
                        1. div-add-revN/A

                          \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                        2. lower-/.f64N/A

                          \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                        3. +-commutativeN/A

                          \[\leadsto \frac{\color{blue}{{a2}^{2} + {a1}^{2}}}{\sqrt{2}} \]
                        4. unpow2N/A

                          \[\leadsto \frac{\color{blue}{a2 \cdot a2} + {a1}^{2}}{\sqrt{2}} \]
                        5. lower-fma.f64N/A

                          \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(a2, a2, {a1}^{2}\right)}}{\sqrt{2}} \]
                        6. unpow2N/A

                          \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                        7. lower-*.f64N/A

                          \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                        8. lower-sqrt.f6469.2

                          \[\leadsto \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\color{blue}{\sqrt{2}}} \]
                      5. Applied rewrites69.2%

                        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\sqrt{2}}} \]
                      6. Taylor expanded in a1 around 0

                        \[\leadsto \frac{{a2}^{2}}{\color{blue}{\sqrt{2}}} \]
                      7. Step-by-step derivation
                        1. Applied rewrites39.1%

                          \[\leadsto a2 \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
                        2. Add Preprocessing

                        Alternative 12: 26.2% accurate, 9.9× speedup?

                        \[\begin{array}{l} a2_m = \left|a2\right| \\ [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\ \\ a1 \cdot \frac{a1}{\sqrt{2}} \end{array} \]
                        a2_m = (fabs.f64 a2)
                        NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                        (FPCore (a1 a2_m th) :precision binary64 (* a1 (/ a1 (sqrt 2.0))))
                        a2_m = fabs(a2);
                        assert(a1 < a2_m && a2_m < th);
                        double code(double a1, double a2_m, double th) {
                        	return a1 * (a1 / sqrt(2.0));
                        }
                        
                        a2_m = abs(a2)
                        NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                        real(8) function code(a1, a2_m, th)
                            real(8), intent (in) :: a1
                            real(8), intent (in) :: a2_m
                            real(8), intent (in) :: th
                            code = a1 * (a1 / sqrt(2.0d0))
                        end function
                        
                        a2_m = Math.abs(a2);
                        assert a1 < a2_m && a2_m < th;
                        public static double code(double a1, double a2_m, double th) {
                        	return a1 * (a1 / Math.sqrt(2.0));
                        }
                        
                        a2_m = math.fabs(a2)
                        [a1, a2_m, th] = sort([a1, a2_m, th])
                        def code(a1, a2_m, th):
                        	return a1 * (a1 / math.sqrt(2.0))
                        
                        a2_m = abs(a2)
                        a1, a2_m, th = sort([a1, a2_m, th])
                        function code(a1, a2_m, th)
                        	return Float64(a1 * Float64(a1 / sqrt(2.0)))
                        end
                        
                        a2_m = abs(a2);
                        a1, a2_m, th = num2cell(sort([a1, a2_m, th])){:}
                        function tmp = code(a1, a2_m, th)
                        	tmp = a1 * (a1 / sqrt(2.0));
                        end
                        
                        a2_m = N[Abs[a2], $MachinePrecision]
                        NOTE: a1, a2_m, and th should be sorted in increasing order before calling this function.
                        code[a1_, a2$95$m_, th_] := N[(a1 * N[(a1 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                        
                        \begin{array}{l}
                        a2_m = \left|a2\right|
                        \\
                        [a1, a2_m, th] = \mathsf{sort}([a1, a2_m, th])\\
                        \\
                        a1 \cdot \frac{a1}{\sqrt{2}}
                        \end{array}
                        
                        Derivation
                        1. Initial program 99.5%

                          \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
                        2. Add Preprocessing
                        3. Taylor expanded in th around 0

                          \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
                        4. Step-by-step derivation
                          1. div-add-revN/A

                            \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                          2. lower-/.f64N/A

                            \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
                          3. +-commutativeN/A

                            \[\leadsto \frac{\color{blue}{{a2}^{2} + {a1}^{2}}}{\sqrt{2}} \]
                          4. unpow2N/A

                            \[\leadsto \frac{\color{blue}{a2 \cdot a2} + {a1}^{2}}{\sqrt{2}} \]
                          5. lower-fma.f64N/A

                            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(a2, a2, {a1}^{2}\right)}}{\sqrt{2}} \]
                          6. unpow2N/A

                            \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                          7. lower-*.f64N/A

                            \[\leadsto \frac{\mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)}{\sqrt{2}} \]
                          8. lower-sqrt.f6469.2

                            \[\leadsto \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\color{blue}{\sqrt{2}}} \]
                        5. Applied rewrites69.2%

                          \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\sqrt{2}}} \]
                        6. Taylor expanded in a1 around inf

                          \[\leadsto \frac{{a1}^{2}}{\color{blue}{\sqrt{2}}} \]
                        7. Step-by-step derivation
                          1. Applied rewrites40.9%

                            \[\leadsto a1 \cdot \color{blue}{\frac{a1}{\sqrt{2}}} \]
                          2. Add Preprocessing

                          Reproduce

                          ?
                          herbie shell --seed 2024333 
                          (FPCore (a1 a2 th)
                            :name "Migdal et al, Equation (64)"
                            :precision binary64
                            (+ (* (/ (cos th) (sqrt 2.0)) (* a1 a1)) (* (/ (cos th) (sqrt 2.0)) (* a2 a2))))