Migdal et al, Equation (64)

Percentage Accurate: 99.5% → 99.6%
Time: 8.0s
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, 1.9× speedup?

\[\begin{array}{l} \\ \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (/ (* (fma a2 a2 (* a1 a1)) (cos th)) (sqrt 2.0)))
double code(double a1, double a2, double th) {
	return (fma(a2, a2, (a1 * a1)) * cos(th)) / sqrt(2.0);
}
function code(a1, a2, th)
	return Float64(Float64(fma(a2, a2, Float64(a1 * a1)) * cos(th)) / sqrt(2.0))
end
code[a1_, a2_, th_] := N[(N[(N[(a2 * a2 + N[(a1 * a1), $MachinePrecision]), $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}}
\end{array}
Derivation
  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

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

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

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

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

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

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

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

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

      \[\leadsto \frac{\left(\color{blue}{a2 \cdot a2} + a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}} \]
    12. lower-fma.f6499.7

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

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

Alternative 2: 76.0% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right) \leq -4 \cdot 10^{-271}:\\ \;\;\;\;\mathsf{fma}\left(th \cdot th, -0.5, 1\right) \cdot \left(a2 \cdot \frac{a2}{\sqrt{2}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}\\ \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (if (<= (+ (* t_1 (* a1 a1)) (* t_1 (* a2 a2))) -4e-271)
     (* (fma (* th th) -0.5 1.0) (* a2 (/ a2 (sqrt 2.0))))
     (/ (fma a1 a1 (* a2 a2)) (sqrt 2.0)))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	double tmp;
	if (((t_1 * (a1 * a1)) + (t_1 * (a2 * a2))) <= -4e-271) {
		tmp = fma((th * th), -0.5, 1.0) * (a2 * (a2 / sqrt(2.0)));
	} else {
		tmp = fma(a1, a1, (a2 * a2)) / sqrt(2.0);
	}
	return tmp;
}
function code(a1, a2, 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 * a2))) <= -4e-271)
		tmp = Float64(fma(Float64(th * th), -0.5, 1.0) * Float64(a2 * Float64(a2 / sqrt(2.0))));
	else
		tmp = Float64(fma(a1, a1, Float64(a2 * a2)) / sqrt(2.0));
	end
	return tmp
end
code[a1_, a2_, 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 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -4e-271], N[(N[(N[(th * th), $MachinePrecision] * -0.5 + 1.0), $MachinePrecision] * N[(a2 * N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a1 * a1 + N[(a2 * a2), $MachinePrecision]), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\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 \cdot a2\right) \leq -4 \cdot 10^{-271}:\\
\;\;\;\;\mathsf{fma}\left(th \cdot th, -0.5, 1\right) \cdot \left(a2 \cdot \frac{a2}{\sqrt{2}}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\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))) < -3.99999999999999985e-271

    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.f6444.9

        \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
    5. Applied rewrites44.9%

      \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
    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 rewrites28.4%

        \[\leadsto \mathsf{fma}\left(th \cdot th, -0.5, 1\right) \cdot \color{blue}{\left(a2 \cdot \frac{a2}{\sqrt{2}}\right)} \]

      if -3.99999999999999985e-271 < (+.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

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

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

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

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

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

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

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

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

          \[\leadsto \frac{\left(\color{blue}{a2 \cdot a2} + a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}} \]
        12. lower-fma.f6499.7

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

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

        \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
      6. Step-by-step derivation
        1. lower-/.f64N/A

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

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

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

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

          \[\leadsto \frac{\mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)}{\sqrt{2}} \]
        6. lower-sqrt.f6489.8

          \[\leadsto \frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\color{blue}{\sqrt{2}}} \]
      7. Applied rewrites89.8%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}} \]
    8. Recombined 2 regimes into one program.
    9. Final simplification77.3%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \leq -4 \cdot 10^{-271}:\\ \;\;\;\;\mathsf{fma}\left(th \cdot th, -0.5, 1\right) \cdot \left(a2 \cdot \frac{a2}{\sqrt{2}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}\\ \end{array} \]
    10. Add Preprocessing

    Alternative 3: 99.6% accurate, 1.9× speedup?

    \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\sqrt{2}} \cdot \cos th \end{array} \]
    (FPCore (a1 a2 th)
     :precision binary64
     (* (/ (fma a2 a2 (* a1 a1)) (sqrt 2.0)) (cos th)))
    double code(double a1, double a2, double th) {
    	return (fma(a2, a2, (a1 * a1)) / sqrt(2.0)) * cos(th);
    }
    
    function code(a1, a2, th)
    	return Float64(Float64(fma(a2, a2, Float64(a1 * a1)) / sqrt(2.0)) * cos(th))
    end
    
    code[a1_, a2_, th_] := N[(N[(N[(a2 * a2 + N[(a1 * a1), $MachinePrecision]), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}{\sqrt{2}} \cdot \cos th
    \end{array}
    
    Derivation
    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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{\color{blue}{a2 \cdot a2} + a1 \cdot a1}{\sqrt{2}} \cdot \cos th \]
      15. lower-fma.f6499.6

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

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

    Alternative 4: 57.0% accurate, 1.9× speedup?

    \[\begin{array}{l} \\ \frac{\cos th \cdot a2}{\frac{\sqrt{2}}{a2}} \end{array} \]
    (FPCore (a1 a2 th) :precision binary64 (/ (* (cos th) a2) (/ (sqrt 2.0) a2)))
    double code(double a1, double a2, double th) {
    	return (cos(th) * a2) / (sqrt(2.0) / a2);
    }
    
    real(8) function code(a1, a2, th)
        real(8), intent (in) :: a1
        real(8), intent (in) :: a2
        real(8), intent (in) :: th
        code = (cos(th) * a2) / (sqrt(2.0d0) / a2)
    end function
    
    public static double code(double a1, double a2, double th) {
    	return (Math.cos(th) * a2) / (Math.sqrt(2.0) / a2);
    }
    
    def code(a1, a2, th):
    	return (math.cos(th) * a2) / (math.sqrt(2.0) / a2)
    
    function code(a1, a2, th)
    	return Float64(Float64(cos(th) * a2) / Float64(sqrt(2.0) / a2))
    end
    
    function tmp = code(a1, a2, th)
    	tmp = (cos(th) * a2) / (sqrt(2.0) / a2);
    end
    
    code[a1_, a2_, th_] := N[(N[(N[Cos[th], $MachinePrecision] * a2), $MachinePrecision] / N[(N[Sqrt[2.0], $MachinePrecision] / a2), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\cos th \cdot a2}{\frac{\sqrt{2}}{a2}}
    \end{array}
    
    Derivation
    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. 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.f6457.5

        \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
    5. Applied rewrites57.5%

      \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
    6. Step-by-step derivation
      1. Applied rewrites57.6%

        \[\leadsto \frac{\cos th \cdot a2}{\color{blue}{\frac{\sqrt{2}}{a2}}} \]
      2. Final simplification57.6%

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

      Alternative 5: 57.0% accurate, 2.0× speedup?

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

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

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

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

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

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

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

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

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

          \[\leadsto \frac{\left(\color{blue}{a2 \cdot a2} + a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}} \]
        12. lower-fma.f6499.7

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

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

        \[\leadsto \frac{\color{blue}{{a2}^{2}} \cdot \cos th}{\sqrt{2}} \]
      6. Step-by-step derivation
        1. unpow2N/A

          \[\leadsto \frac{\color{blue}{\left(a2 \cdot a2\right)} \cdot \cos th}{\sqrt{2}} \]
        2. lower-*.f6457.5

          \[\leadsto \frac{\color{blue}{\left(a2 \cdot a2\right)} \cdot \cos th}{\sqrt{2}} \]
      7. Applied rewrites57.5%

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

      Alternative 6: 57.0% accurate, 2.0× speedup?

      \[\begin{array}{l} \\ \left(\frac{a2}{\sqrt{2}} \cdot \cos th\right) \cdot a2 \end{array} \]
      (FPCore (a1 a2 th) :precision binary64 (* (* (/ a2 (sqrt 2.0)) (cos th)) a2))
      double code(double a1, double a2, double th) {
      	return ((a2 / sqrt(2.0)) * cos(th)) * a2;
      }
      
      real(8) function code(a1, a2, th)
          real(8), intent (in) :: a1
          real(8), intent (in) :: a2
          real(8), intent (in) :: th
          code = ((a2 / sqrt(2.0d0)) * cos(th)) * a2
      end function
      
      public static double code(double a1, double a2, double th) {
      	return ((a2 / Math.sqrt(2.0)) * Math.cos(th)) * a2;
      }
      
      def code(a1, a2, th):
      	return ((a2 / math.sqrt(2.0)) * math.cos(th)) * a2
      
      function code(a1, a2, th)
      	return Float64(Float64(Float64(a2 / sqrt(2.0)) * cos(th)) * a2)
      end
      
      function tmp = code(a1, a2, th)
      	tmp = ((a2 / sqrt(2.0)) * cos(th)) * a2;
      end
      
      code[a1_, a2_, th_] := N[(N[(N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision] * a2), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \left(\frac{a2}{\sqrt{2}} \cdot \cos th\right) \cdot a2
      \end{array}
      
      Derivation
      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. 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.f6457.5

          \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
      5. Applied rewrites57.5%

        \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
      6. Step-by-step derivation
        1. Applied rewrites57.5%

          \[\leadsto \left(\frac{a2}{\sqrt{2}} \cdot \cos th\right) \cdot \color{blue}{a2} \]
        2. Final simplification57.5%

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

        Alternative 7: 57.0% accurate, 2.0× speedup?

        \[\begin{array}{l} \\ \left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}} \end{array} \]
        (FPCore (a1 a2 th) :precision binary64 (* (* (cos th) a2) (/ a2 (sqrt 2.0))))
        double code(double a1, double a2, double th) {
        	return (cos(th) * a2) * (a2 / sqrt(2.0));
        }
        
        real(8) function code(a1, a2, th)
            real(8), intent (in) :: a1
            real(8), intent (in) :: a2
            real(8), intent (in) :: th
            code = (cos(th) * a2) * (a2 / sqrt(2.0d0))
        end function
        
        public static double code(double a1, double a2, double th) {
        	return (Math.cos(th) * a2) * (a2 / Math.sqrt(2.0));
        }
        
        def code(a1, a2, th):
        	return (math.cos(th) * a2) * (a2 / math.sqrt(2.0))
        
        function code(a1, a2, th)
        	return Float64(Float64(cos(th) * a2) * Float64(a2 / sqrt(2.0)))
        end
        
        function tmp = code(a1, a2, th)
        	tmp = (cos(th) * a2) * (a2 / sqrt(2.0));
        end
        
        code[a1_, a2_, th_] := N[(N[(N[Cos[th], $MachinePrecision] * a2), $MachinePrecision] * N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}
        \end{array}
        
        Derivation
        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. 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.f6457.5

            \[\leadsto \left(\cos th \cdot a2\right) \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
        5. Applied rewrites57.5%

          \[\leadsto \color{blue}{\left(\cos th \cdot a2\right) \cdot \frac{a2}{\sqrt{2}}} \]
        6. Final simplification57.5%

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

        Alternative 8: 67.3% accurate, 8.1× speedup?

        \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}} \end{array} \]
        (FPCore (a1 a2 th) :precision binary64 (/ (fma a1 a1 (* a2 a2)) (sqrt 2.0)))
        double code(double a1, double a2, double th) {
        	return fma(a1, a1, (a2 * a2)) / sqrt(2.0);
        }
        
        function code(a1, a2, th)
        	return Float64(fma(a1, a1, Float64(a2 * a2)) / sqrt(2.0))
        end
        
        code[a1_, a2_, th_] := N[(N[(a1 * a1 + N[(a2 * a2), $MachinePrecision]), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}
        \end{array}
        
        Derivation
        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

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

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

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

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

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

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

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

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

            \[\leadsto \frac{\left(\color{blue}{a2 \cdot a2} + a1 \cdot a1\right) \cdot \cos th}{\sqrt{2}} \]
          12. lower-fma.f6499.7

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

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

          \[\leadsto \color{blue}{\frac{{a1}^{2} + {a2}^{2}}{\sqrt{2}}} \]
        6. Step-by-step derivation
          1. lower-/.f64N/A

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

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

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

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

            \[\leadsto \frac{\mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)}{\sqrt{2}} \]
          6. lower-sqrt.f6471.7

            \[\leadsto \frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\color{blue}{\sqrt{2}}} \]
        7. Applied rewrites71.7%

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

        Alternative 9: 67.3% accurate, 8.3× speedup?

        \[\begin{array}{l} \\ \left(\sqrt{2} \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot 0.5 \end{array} \]
        (FPCore (a1 a2 th)
         :precision binary64
         (* (* (sqrt 2.0) (fma a2 a2 (* a1 a1))) 0.5))
        double code(double a1, double a2, double th) {
        	return (sqrt(2.0) * fma(a2, a2, (a1 * a1))) * 0.5;
        }
        
        function code(a1, a2, th)
        	return Float64(Float64(sqrt(2.0) * fma(a2, a2, Float64(a1 * a1))) * 0.5)
        end
        
        code[a1_, a2_, th_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[(a2 * a2 + N[(a1 * a1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \left(\sqrt{2} \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot 0.5
        \end{array}
        
        Derivation
        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. 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. +-commutativeN/A

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

            \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} + \frac{{a1}^{2}}{\sqrt{2}} \]
          3. associate-*l/N/A

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1}{\sqrt{2}}} \cdot a1\right) \]
          11. lower-sqrt.f6471.7

            \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\color{blue}{\sqrt{2}}} \cdot a1\right) \]
        5. Applied rewrites71.7%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\sqrt{2}} \cdot a1\right)} \]
        6. Step-by-step derivation
          1. Applied rewrites71.7%

            \[\leadsto \mathsf{fma}\left(a2 \cdot a2, \sqrt{2}, \sqrt{2} \cdot \left(a1 \cdot a1\right)\right) \cdot \color{blue}{0.5} \]
          2. Step-by-step derivation
            1. Applied rewrites71.7%

              \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot 0.5 \]
            2. Final simplification71.7%

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

            Alternative 10: 40.0% accurate, 9.9× speedup?

            \[\begin{array}{l} \\ a2 \cdot \frac{a2}{\sqrt{2}} \end{array} \]
            (FPCore (a1 a2 th) :precision binary64 (* a2 (/ a2 (sqrt 2.0))))
            double code(double a1, double a2, double th) {
            	return a2 * (a2 / sqrt(2.0));
            }
            
            real(8) function code(a1, a2, th)
                real(8), intent (in) :: a1
                real(8), intent (in) :: a2
                real(8), intent (in) :: th
                code = a2 * (a2 / sqrt(2.0d0))
            end function
            
            public static double code(double a1, double a2, double th) {
            	return a2 * (a2 / Math.sqrt(2.0));
            }
            
            def code(a1, a2, th):
            	return a2 * (a2 / math.sqrt(2.0))
            
            function code(a1, a2, th)
            	return Float64(a2 * Float64(a2 / sqrt(2.0)))
            end
            
            function tmp = code(a1, a2, th)
            	tmp = a2 * (a2 / sqrt(2.0));
            end
            
            code[a1_, a2_, th_] := N[(a2 * N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            a2 \cdot \frac{a2}{\sqrt{2}}
            \end{array}
            
            Derivation
            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. 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. +-commutativeN/A

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

                \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} + \frac{{a1}^{2}}{\sqrt{2}} \]
              3. associate-*l/N/A

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1}{\sqrt{2}}} \cdot a1\right) \]
              11. lower-sqrt.f6471.7

                \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\color{blue}{\sqrt{2}}} \cdot a1\right) \]
            5. Applied rewrites71.7%

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

              \[\leadsto \frac{{a2}^{2}}{\color{blue}{\sqrt{2}}} \]
            7. Step-by-step derivation
              1. Applied rewrites44.7%

                \[\leadsto a2 \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
              2. Final simplification44.7%

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

              Alternative 11: 40.0% accurate, 10.2× speedup?

              \[\begin{array}{l} \\ \left(\left(0.5 \cdot \sqrt{2}\right) \cdot a2\right) \cdot a2 \end{array} \]
              (FPCore (a1 a2 th) :precision binary64 (* (* (* 0.5 (sqrt 2.0)) a2) a2))
              double code(double a1, double a2, double th) {
              	return ((0.5 * sqrt(2.0)) * a2) * a2;
              }
              
              real(8) function code(a1, a2, th)
                  real(8), intent (in) :: a1
                  real(8), intent (in) :: a2
                  real(8), intent (in) :: th
                  code = ((0.5d0 * sqrt(2.0d0)) * a2) * a2
              end function
              
              public static double code(double a1, double a2, double th) {
              	return ((0.5 * Math.sqrt(2.0)) * a2) * a2;
              }
              
              def code(a1, a2, th):
              	return ((0.5 * math.sqrt(2.0)) * a2) * a2
              
              function code(a1, a2, th)
              	return Float64(Float64(Float64(0.5 * sqrt(2.0)) * a2) * a2)
              end
              
              function tmp = code(a1, a2, th)
              	tmp = ((0.5 * sqrt(2.0)) * a2) * a2;
              end
              
              code[a1_, a2_, th_] := N[(N[(N[(0.5 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * a2), $MachinePrecision] * a2), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \left(\left(0.5 \cdot \sqrt{2}\right) \cdot a2\right) \cdot a2
              \end{array}
              
              Derivation
              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. 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. +-commutativeN/A

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

                  \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} + \frac{{a1}^{2}}{\sqrt{2}} \]
                3. associate-*l/N/A

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1}{\sqrt{2}}} \cdot a1\right) \]
                11. lower-sqrt.f6471.7

                  \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\color{blue}{\sqrt{2}}} \cdot a1\right) \]
              5. Applied rewrites71.7%

                \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\sqrt{2}} \cdot a1\right)} \]
              6. Step-by-step derivation
                1. Applied rewrites71.7%

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

                  \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({a2}^{2} \cdot \sqrt{2}\right)} \]
                3. Step-by-step derivation
                  1. Applied rewrites44.7%

                    \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot a2\right) \cdot \color{blue}{a2} \]
                  2. Final simplification44.7%

                    \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot a2\right) \cdot a2 \]
                  3. Add Preprocessing

                  Alternative 12: 40.2% accurate, 10.2× speedup?

                  \[\begin{array}{l} \\ \left(a1 \cdot a1\right) \cdot \left(0.5 \cdot \sqrt{2}\right) \end{array} \]
                  (FPCore (a1 a2 th) :precision binary64 (* (* a1 a1) (* 0.5 (sqrt 2.0))))
                  double code(double a1, double a2, double th) {
                  	return (a1 * a1) * (0.5 * sqrt(2.0));
                  }
                  
                  real(8) function code(a1, a2, th)
                      real(8), intent (in) :: a1
                      real(8), intent (in) :: a2
                      real(8), intent (in) :: th
                      code = (a1 * a1) * (0.5d0 * sqrt(2.0d0))
                  end function
                  
                  public static double code(double a1, double a2, double th) {
                  	return (a1 * a1) * (0.5 * Math.sqrt(2.0));
                  }
                  
                  def code(a1, a2, th):
                  	return (a1 * a1) * (0.5 * math.sqrt(2.0))
                  
                  function code(a1, a2, th)
                  	return Float64(Float64(a1 * a1) * Float64(0.5 * sqrt(2.0)))
                  end
                  
                  function tmp = code(a1, a2, th)
                  	tmp = (a1 * a1) * (0.5 * sqrt(2.0));
                  end
                  
                  code[a1_, a2_, th_] := N[(N[(a1 * a1), $MachinePrecision] * N[(0.5 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \left(a1 \cdot a1\right) \cdot \left(0.5 \cdot \sqrt{2}\right)
                  \end{array}
                  
                  Derivation
                  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. 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. +-commutativeN/A

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

                      \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} + \frac{{a1}^{2}}{\sqrt{2}} \]
                    3. associate-*l/N/A

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

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

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

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

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

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

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

                      \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1}{\sqrt{2}}} \cdot a1\right) \]
                    11. lower-sqrt.f6471.7

                      \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\color{blue}{\sqrt{2}}} \cdot a1\right) \]
                  5. Applied rewrites71.7%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1}{\sqrt{2}} \cdot a1\right)} \]
                  6. Step-by-step derivation
                    1. Applied rewrites71.7%

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

                      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({a1}^{2} \cdot \sqrt{2}\right)} \]
                    3. Step-by-step derivation
                      1. Applied rewrites46.0%

                        \[\leadsto \left(\left(0.5 \cdot \sqrt{2}\right) \cdot a1\right) \cdot \color{blue}{a1} \]
                      2. Step-by-step derivation
                        1. Applied rewrites46.0%

                          \[\leadsto \left(a1 \cdot a1\right) \cdot \left(0.5 \cdot \color{blue}{\sqrt{2}}\right) \]
                        2. Final simplification46.0%

                          \[\leadsto \left(a1 \cdot a1\right) \cdot \left(0.5 \cdot \sqrt{2}\right) \]
                        3. Add Preprocessing

                        Reproduce

                        ?
                        herbie shell --seed 2024304 
                        (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))))