VandenBroeck and Keller, Equation (6)

Percentage Accurate: 76.2% → 96.7%
Time: 1.6min
Alternatives: 9
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right) \end{array} \]
(FPCore (F l)
 :precision binary64
 (- (* PI l) (* (/ 1.0 (* F F)) (tan (* PI l)))))
double code(double F, double l) {
	return (((double) M_PI) * l) - ((1.0 / (F * F)) * tan((((double) M_PI) * l)));
}
public static double code(double F, double l) {
	return (Math.PI * l) - ((1.0 / (F * F)) * Math.tan((Math.PI * l)));
}
def code(F, l):
	return (math.pi * l) - ((1.0 / (F * F)) * math.tan((math.pi * l)))
function code(F, l)
	return Float64(Float64(pi * l) - Float64(Float64(1.0 / Float64(F * F)) * tan(Float64(pi * l))))
end
function tmp = code(F, l)
	tmp = (pi * l) - ((1.0 / (F * F)) * tan((pi * l)));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] - N[(N[(1.0 / N[(F * F), $MachinePrecision]), $MachinePrecision] * N[Tan[N[(Pi * l), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 9 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 76.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right) \end{array} \]
(FPCore (F l)
 :precision binary64
 (- (* PI l) (* (/ 1.0 (* F F)) (tan (* PI l)))))
double code(double F, double l) {
	return (((double) M_PI) * l) - ((1.0 / (F * F)) * tan((((double) M_PI) * l)));
}
public static double code(double F, double l) {
	return (Math.PI * l) - ((1.0 / (F * F)) * Math.tan((Math.PI * l)));
}
def code(F, l):
	return (math.pi * l) - ((1.0 / (F * F)) * math.tan((math.pi * l)))
function code(F, l)
	return Float64(Float64(pi * l) - Float64(Float64(1.0 / Float64(F * F)) * tan(Float64(pi * l))))
end
function tmp = code(F, l)
	tmp = (pi * l) - ((1.0 / (F * F)) * tan((pi * l)));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] - N[(N[(1.0 / N[(F * F), $MachinePrecision]), $MachinePrecision] * N[Tan[N[(Pi * l), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell - \frac{1}{F \cdot F} \cdot \tan \left(\pi \cdot \ell\right)
\end{array}

Alternative 1: 96.7% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.008333333333333333 \cdot {\pi}^{5}\\ t_1 := {\pi}^{6} \cdot 0.1111111111111111\\ t_2 := \frac{F}{{\pi}^{2}}\\ t_3 := {\pi}^{3} \cdot 0.3333333333333333\\ t_4 := \mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_3, {\pi}^{5} \cdot 0.041666666666666664\right)\\ t_5 := t_4 - t_0\\ t_6 := t_0 - t_4\\ t_7 := \frac{F}{{\pi}^{3}}\\ \pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_3}}\right) - \mathsf{log1p}\left(\mathsf{expm1}\left(\left(\mathsf{fma}\left(t_2, -0.0001984126984126984 \cdot {\pi}^{7} - \mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_6, \mathsf{fma}\left(-0.001388888888888889, {\pi}^{7}, {\pi}^{3} \cdot \left(0.013888888888888888 \cdot {\pi}^{4}\right)\right)\right), \left(\frac{t_6}{\frac{{\pi}^{3}}{F}} - \frac{F \cdot t_1}{{\pi}^{4}}\right) \cdot \left({\pi}^{3} \cdot -0.3333333333333333\right)\right) + t_3 \cdot \left(t_7 \cdot t_5\right)\right) \cdot {\ell}^{5}\right)\right)\right) + {\ell}^{3} \cdot \left(t_1 \cdot t_7 + t_2 \cdot t_5\right)\right)} \end{array} \end{array} \]
(FPCore (F l)
 :precision binary64
 (let* ((t_0 (* 0.008333333333333333 (pow PI 5.0)))
        (t_1 (* (pow PI 6.0) 0.1111111111111111))
        (t_2 (/ F (pow PI 2.0)))
        (t_3 (* (pow PI 3.0) 0.3333333333333333))
        (t_4
         (fma -0.5 (* (pow PI 2.0) t_3) (* (pow PI 5.0) 0.041666666666666664)))
        (t_5 (- t_4 t_0))
        (t_6 (- t_0 t_4))
        (t_7 (/ F (pow PI 3.0))))
   (+
    (* PI l)
    (/
     -1.0
     (*
      F
      (+
       (-
        (- (/ F (* PI l)) (/ F (/ (/ (pow PI 2.0) l) t_3)))
        (log1p
         (expm1
          (*
           (+
            (fma
             t_2
             (-
              (* -0.0001984126984126984 (pow PI 7.0))
              (fma
               -0.5
               (* (pow PI 2.0) t_6)
               (fma
                -0.001388888888888889
                (pow PI 7.0)
                (* (pow PI 3.0) (* 0.013888888888888888 (pow PI 4.0))))))
             (*
              (- (/ t_6 (/ (pow PI 3.0) F)) (/ (* F t_1) (pow PI 4.0)))
              (* (pow PI 3.0) -0.3333333333333333)))
            (* t_3 (* t_7 t_5)))
           (pow l 5.0)))))
       (* (pow l 3.0) (+ (* t_1 t_7) (* t_2 t_5)))))))))
double code(double F, double l) {
	double t_0 = 0.008333333333333333 * pow(((double) M_PI), 5.0);
	double t_1 = pow(((double) M_PI), 6.0) * 0.1111111111111111;
	double t_2 = F / pow(((double) M_PI), 2.0);
	double t_3 = pow(((double) M_PI), 3.0) * 0.3333333333333333;
	double t_4 = fma(-0.5, (pow(((double) M_PI), 2.0) * t_3), (pow(((double) M_PI), 5.0) * 0.041666666666666664));
	double t_5 = t_4 - t_0;
	double t_6 = t_0 - t_4;
	double t_7 = F / pow(((double) M_PI), 3.0);
	return (((double) M_PI) * l) + (-1.0 / (F * ((((F / (((double) M_PI) * l)) - (F / ((pow(((double) M_PI), 2.0) / l) / t_3))) - log1p(expm1(((fma(t_2, ((-0.0001984126984126984 * pow(((double) M_PI), 7.0)) - fma(-0.5, (pow(((double) M_PI), 2.0) * t_6), fma(-0.001388888888888889, pow(((double) M_PI), 7.0), (pow(((double) M_PI), 3.0) * (0.013888888888888888 * pow(((double) M_PI), 4.0)))))), (((t_6 / (pow(((double) M_PI), 3.0) / F)) - ((F * t_1) / pow(((double) M_PI), 4.0))) * (pow(((double) M_PI), 3.0) * -0.3333333333333333))) + (t_3 * (t_7 * t_5))) * pow(l, 5.0))))) + (pow(l, 3.0) * ((t_1 * t_7) + (t_2 * t_5))))));
}
function code(F, l)
	t_0 = Float64(0.008333333333333333 * (pi ^ 5.0))
	t_1 = Float64((pi ^ 6.0) * 0.1111111111111111)
	t_2 = Float64(F / (pi ^ 2.0))
	t_3 = Float64((pi ^ 3.0) * 0.3333333333333333)
	t_4 = fma(-0.5, Float64((pi ^ 2.0) * t_3), Float64((pi ^ 5.0) * 0.041666666666666664))
	t_5 = Float64(t_4 - t_0)
	t_6 = Float64(t_0 - t_4)
	t_7 = Float64(F / (pi ^ 3.0))
	return Float64(Float64(pi * l) + Float64(-1.0 / Float64(F * Float64(Float64(Float64(Float64(F / Float64(pi * l)) - Float64(F / Float64(Float64((pi ^ 2.0) / l) / t_3))) - log1p(expm1(Float64(Float64(fma(t_2, Float64(Float64(-0.0001984126984126984 * (pi ^ 7.0)) - fma(-0.5, Float64((pi ^ 2.0) * t_6), fma(-0.001388888888888889, (pi ^ 7.0), Float64((pi ^ 3.0) * Float64(0.013888888888888888 * (pi ^ 4.0)))))), Float64(Float64(Float64(t_6 / Float64((pi ^ 3.0) / F)) - Float64(Float64(F * t_1) / (pi ^ 4.0))) * Float64((pi ^ 3.0) * -0.3333333333333333))) + Float64(t_3 * Float64(t_7 * t_5))) * (l ^ 5.0))))) + Float64((l ^ 3.0) * Float64(Float64(t_1 * t_7) + Float64(t_2 * t_5)))))))
end
code[F_, l_] := Block[{t$95$0 = N[(0.008333333333333333 * N[Power[Pi, 5.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[Power[Pi, 6.0], $MachinePrecision] * 0.1111111111111111), $MachinePrecision]}, Block[{t$95$2 = N[(F / N[Power[Pi, 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Power[Pi, 3.0], $MachinePrecision] * 0.3333333333333333), $MachinePrecision]}, Block[{t$95$4 = N[(-0.5 * N[(N[Power[Pi, 2.0], $MachinePrecision] * t$95$3), $MachinePrecision] + N[(N[Power[Pi, 5.0], $MachinePrecision] * 0.041666666666666664), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$5 = N[(t$95$4 - t$95$0), $MachinePrecision]}, Block[{t$95$6 = N[(t$95$0 - t$95$4), $MachinePrecision]}, Block[{t$95$7 = N[(F / N[Power[Pi, 3.0], $MachinePrecision]), $MachinePrecision]}, N[(N[(Pi * l), $MachinePrecision] + N[(-1.0 / N[(F * N[(N[(N[(N[(F / N[(Pi * l), $MachinePrecision]), $MachinePrecision] - N[(F / N[(N[(N[Power[Pi, 2.0], $MachinePrecision] / l), $MachinePrecision] / t$95$3), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[Log[1 + N[(Exp[N[(N[(N[(t$95$2 * N[(N[(-0.0001984126984126984 * N[Power[Pi, 7.0], $MachinePrecision]), $MachinePrecision] - N[(-0.5 * N[(N[Power[Pi, 2.0], $MachinePrecision] * t$95$6), $MachinePrecision] + N[(-0.001388888888888889 * N[Power[Pi, 7.0], $MachinePrecision] + N[(N[Power[Pi, 3.0], $MachinePrecision] * N[(0.013888888888888888 * N[Power[Pi, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(N[(t$95$6 / N[(N[Power[Pi, 3.0], $MachinePrecision] / F), $MachinePrecision]), $MachinePrecision] - N[(N[(F * t$95$1), $MachinePrecision] / N[Power[Pi, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Power[Pi, 3.0], $MachinePrecision] * -0.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 * N[(t$95$7 * t$95$5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[l, 5.0], $MachinePrecision]), $MachinePrecision]] - 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Power[l, 3.0], $MachinePrecision] * N[(N[(t$95$1 * t$95$7), $MachinePrecision] + N[(t$95$2 * t$95$5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.008333333333333333 \cdot {\pi}^{5}\\
t_1 := {\pi}^{6} \cdot 0.1111111111111111\\
t_2 := \frac{F}{{\pi}^{2}}\\
t_3 := {\pi}^{3} \cdot 0.3333333333333333\\
t_4 := \mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_3, {\pi}^{5} \cdot 0.041666666666666664\right)\\
t_5 := t_4 - t_0\\
t_6 := t_0 - t_4\\
t_7 := \frac{F}{{\pi}^{3}}\\
\pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_3}}\right) - \mathsf{log1p}\left(\mathsf{expm1}\left(\left(\mathsf{fma}\left(t_2, -0.0001984126984126984 \cdot {\pi}^{7} - \mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_6, \mathsf{fma}\left(-0.001388888888888889, {\pi}^{7}, {\pi}^{3} \cdot \left(0.013888888888888888 \cdot {\pi}^{4}\right)\right)\right), \left(\frac{t_6}{\frac{{\pi}^{3}}{F}} - \frac{F \cdot t_1}{{\pi}^{4}}\right) \cdot \left({\pi}^{3} \cdot -0.3333333333333333\right)\right) + t_3 \cdot \left(t_7 \cdot t_5\right)\right) \cdot {\ell}^{5}\right)\right)\right) + {\ell}^{3} \cdot \left(t_1 \cdot t_7 + t_2 \cdot t_5\right)\right)}
\end{array}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 2: 96.2% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\pi}^{3} \cdot 0.3333333333333333\\ t_1 := {\pi}^{5} \cdot 0.13333333333333333\\ \pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_0}}\right) + \left(F \cdot {\ell}^{5}\right) \cdot \left(\mathsf{fma}\left(-0.5, t_1, {\pi}^{5} \cdot 0.0125 - 0.3333333333333333 \cdot \left({\pi}^{2} \cdot \left({\pi}^{3} \cdot -0.013888888888888888 - {\pi}^{3} \cdot 0.008333333333333333\right) - t_1\right)\right) - -0.0001984126984126984 \cdot {\pi}^{5}\right)\right) + {\ell}^{3} \cdot \left(\left({\pi}^{6} \cdot 0.1111111111111111\right) \cdot \frac{F}{{\pi}^{3}} + \frac{F}{{\pi}^{2}} \cdot \left(\mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_0, {\pi}^{5} \cdot 0.041666666666666664\right) - 0.008333333333333333 \cdot {\pi}^{5}\right)\right)\right)} \end{array} \end{array} \]
(FPCore (F l)
 :precision binary64
 (let* ((t_0 (* (pow PI 3.0) 0.3333333333333333))
        (t_1 (* (pow PI 5.0) 0.13333333333333333)))
   (+
    (* PI l)
    (/
     -1.0
     (*
      F
      (+
       (+
        (- (/ F (* PI l)) (/ F (/ (/ (pow PI 2.0) l) t_0)))
        (*
         (* F (pow l 5.0))
         (-
          (fma
           -0.5
           t_1
           (-
            (* (pow PI 5.0) 0.0125)
            (*
             0.3333333333333333
             (-
              (*
               (pow PI 2.0)
               (-
                (* (pow PI 3.0) -0.013888888888888888)
                (* (pow PI 3.0) 0.008333333333333333)))
              t_1))))
          (* -0.0001984126984126984 (pow PI 5.0)))))
       (*
        (pow l 3.0)
        (+
         (* (* (pow PI 6.0) 0.1111111111111111) (/ F (pow PI 3.0)))
         (*
          (/ F (pow PI 2.0))
          (-
           (fma
            -0.5
            (* (pow PI 2.0) t_0)
            (* (pow PI 5.0) 0.041666666666666664))
           (* 0.008333333333333333 (pow PI 5.0))))))))))))
double code(double F, double l) {
	double t_0 = pow(((double) M_PI), 3.0) * 0.3333333333333333;
	double t_1 = pow(((double) M_PI), 5.0) * 0.13333333333333333;
	return (((double) M_PI) * l) + (-1.0 / (F * ((((F / (((double) M_PI) * l)) - (F / ((pow(((double) M_PI), 2.0) / l) / t_0))) + ((F * pow(l, 5.0)) * (fma(-0.5, t_1, ((pow(((double) M_PI), 5.0) * 0.0125) - (0.3333333333333333 * ((pow(((double) M_PI), 2.0) * ((pow(((double) M_PI), 3.0) * -0.013888888888888888) - (pow(((double) M_PI), 3.0) * 0.008333333333333333))) - t_1)))) - (-0.0001984126984126984 * pow(((double) M_PI), 5.0))))) + (pow(l, 3.0) * (((pow(((double) M_PI), 6.0) * 0.1111111111111111) * (F / pow(((double) M_PI), 3.0))) + ((F / pow(((double) M_PI), 2.0)) * (fma(-0.5, (pow(((double) M_PI), 2.0) * t_0), (pow(((double) M_PI), 5.0) * 0.041666666666666664)) - (0.008333333333333333 * pow(((double) M_PI), 5.0)))))))));
}
function code(F, l)
	t_0 = Float64((pi ^ 3.0) * 0.3333333333333333)
	t_1 = Float64((pi ^ 5.0) * 0.13333333333333333)
	return Float64(Float64(pi * l) + Float64(-1.0 / Float64(F * Float64(Float64(Float64(Float64(F / Float64(pi * l)) - Float64(F / Float64(Float64((pi ^ 2.0) / l) / t_0))) + Float64(Float64(F * (l ^ 5.0)) * Float64(fma(-0.5, t_1, Float64(Float64((pi ^ 5.0) * 0.0125) - Float64(0.3333333333333333 * Float64(Float64((pi ^ 2.0) * Float64(Float64((pi ^ 3.0) * -0.013888888888888888) - Float64((pi ^ 3.0) * 0.008333333333333333))) - t_1)))) - Float64(-0.0001984126984126984 * (pi ^ 5.0))))) + Float64((l ^ 3.0) * Float64(Float64(Float64((pi ^ 6.0) * 0.1111111111111111) * Float64(F / (pi ^ 3.0))) + Float64(Float64(F / (pi ^ 2.0)) * Float64(fma(-0.5, Float64((pi ^ 2.0) * t_0), Float64((pi ^ 5.0) * 0.041666666666666664)) - Float64(0.008333333333333333 * (pi ^ 5.0))))))))))
end
code[F_, l_] := Block[{t$95$0 = N[(N[Power[Pi, 3.0], $MachinePrecision] * 0.3333333333333333), $MachinePrecision]}, Block[{t$95$1 = N[(N[Power[Pi, 5.0], $MachinePrecision] * 0.13333333333333333), $MachinePrecision]}, N[(N[(Pi * l), $MachinePrecision] + N[(-1.0 / N[(F * N[(N[(N[(N[(F / N[(Pi * l), $MachinePrecision]), $MachinePrecision] - N[(F / N[(N[(N[Power[Pi, 2.0], $MachinePrecision] / l), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(F * N[Power[l, 5.0], $MachinePrecision]), $MachinePrecision] * N[(N[(-0.5 * t$95$1 + N[(N[(N[Power[Pi, 5.0], $MachinePrecision] * 0.0125), $MachinePrecision] - N[(0.3333333333333333 * N[(N[(N[Power[Pi, 2.0], $MachinePrecision] * N[(N[(N[Power[Pi, 3.0], $MachinePrecision] * -0.013888888888888888), $MachinePrecision] - N[(N[Power[Pi, 3.0], $MachinePrecision] * 0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(-0.0001984126984126984 * N[Power[Pi, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Power[l, 3.0], $MachinePrecision] * N[(N[(N[(N[Power[Pi, 6.0], $MachinePrecision] * 0.1111111111111111), $MachinePrecision] * N[(F / N[Power[Pi, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(F / N[Power[Pi, 2.0], $MachinePrecision]), $MachinePrecision] * N[(N[(-0.5 * N[(N[Power[Pi, 2.0], $MachinePrecision] * t$95$0), $MachinePrecision] + N[(N[Power[Pi, 5.0], $MachinePrecision] * 0.041666666666666664), $MachinePrecision]), $MachinePrecision] - N[(0.008333333333333333 * N[Power[Pi, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\pi}^{3} \cdot 0.3333333333333333\\
t_1 := {\pi}^{5} \cdot 0.13333333333333333\\
\pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_0}}\right) + \left(F \cdot {\ell}^{5}\right) \cdot \left(\mathsf{fma}\left(-0.5, t_1, {\pi}^{5} \cdot 0.0125 - 0.3333333333333333 \cdot \left({\pi}^{2} \cdot \left({\pi}^{3} \cdot -0.013888888888888888 - {\pi}^{3} \cdot 0.008333333333333333\right) - t_1\right)\right) - -0.0001984126984126984 \cdot {\pi}^{5}\right)\right) + {\ell}^{3} \cdot \left(\left({\pi}^{6} \cdot 0.1111111111111111\right) \cdot \frac{F}{{\pi}^{3}} + \frac{F}{{\pi}^{2}} \cdot \left(\mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_0, {\pi}^{5} \cdot 0.041666666666666664\right) - 0.008333333333333333 \cdot {\pi}^{5}\right)\right)\right)}
\end{array}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 3: 94.4% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\pi}^{3} \cdot 0.3333333333333333\\ \pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_0}}\right) + {\ell}^{3} \cdot \left(\left({\pi}^{6} \cdot 0.1111111111111111\right) \cdot \frac{F}{{\pi}^{3}} + \frac{F}{{\pi}^{2}} \cdot \left(\mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_0, {\pi}^{5} \cdot 0.041666666666666664\right) - 0.008333333333333333 \cdot {\pi}^{5}\right)\right)\right)} \end{array} \end{array} \]
(FPCore (F l)
 :precision binary64
 (let* ((t_0 (* (pow PI 3.0) 0.3333333333333333)))
   (+
    (* PI l)
    (/
     -1.0
     (*
      F
      (+
       (- (/ F (* PI l)) (/ F (/ (/ (pow PI 2.0) l) t_0)))
       (*
        (pow l 3.0)
        (+
         (* (* (pow PI 6.0) 0.1111111111111111) (/ F (pow PI 3.0)))
         (*
          (/ F (pow PI 2.0))
          (-
           (fma
            -0.5
            (* (pow PI 2.0) t_0)
            (* (pow PI 5.0) 0.041666666666666664))
           (* 0.008333333333333333 (pow PI 5.0))))))))))))
double code(double F, double l) {
	double t_0 = pow(((double) M_PI), 3.0) * 0.3333333333333333;
	return (((double) M_PI) * l) + (-1.0 / (F * (((F / (((double) M_PI) * l)) - (F / ((pow(((double) M_PI), 2.0) / l) / t_0))) + (pow(l, 3.0) * (((pow(((double) M_PI), 6.0) * 0.1111111111111111) * (F / pow(((double) M_PI), 3.0))) + ((F / pow(((double) M_PI), 2.0)) * (fma(-0.5, (pow(((double) M_PI), 2.0) * t_0), (pow(((double) M_PI), 5.0) * 0.041666666666666664)) - (0.008333333333333333 * pow(((double) M_PI), 5.0)))))))));
}
function code(F, l)
	t_0 = Float64((pi ^ 3.0) * 0.3333333333333333)
	return Float64(Float64(pi * l) + Float64(-1.0 / Float64(F * Float64(Float64(Float64(F / Float64(pi * l)) - Float64(F / Float64(Float64((pi ^ 2.0) / l) / t_0))) + Float64((l ^ 3.0) * Float64(Float64(Float64((pi ^ 6.0) * 0.1111111111111111) * Float64(F / (pi ^ 3.0))) + Float64(Float64(F / (pi ^ 2.0)) * Float64(fma(-0.5, Float64((pi ^ 2.0) * t_0), Float64((pi ^ 5.0) * 0.041666666666666664)) - Float64(0.008333333333333333 * (pi ^ 5.0))))))))))
end
code[F_, l_] := Block[{t$95$0 = N[(N[Power[Pi, 3.0], $MachinePrecision] * 0.3333333333333333), $MachinePrecision]}, N[(N[(Pi * l), $MachinePrecision] + N[(-1.0 / N[(F * N[(N[(N[(F / N[(Pi * l), $MachinePrecision]), $MachinePrecision] - N[(F / N[(N[(N[Power[Pi, 2.0], $MachinePrecision] / l), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Power[l, 3.0], $MachinePrecision] * N[(N[(N[(N[Power[Pi, 6.0], $MachinePrecision] * 0.1111111111111111), $MachinePrecision] * N[(F / N[Power[Pi, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(F / N[Power[Pi, 2.0], $MachinePrecision]), $MachinePrecision] * N[(N[(-0.5 * N[(N[Power[Pi, 2.0], $MachinePrecision] * t$95$0), $MachinePrecision] + N[(N[Power[Pi, 5.0], $MachinePrecision] * 0.041666666666666664), $MachinePrecision]), $MachinePrecision] - N[(0.008333333333333333 * N[Power[Pi, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\pi}^{3} \cdot 0.3333333333333333\\
\pi \cdot \ell + \frac{-1}{F \cdot \left(\left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{t_0}}\right) + {\ell}^{3} \cdot \left(\left({\pi}^{6} \cdot 0.1111111111111111\right) \cdot \frac{F}{{\pi}^{3}} + \frac{F}{{\pi}^{2}} \cdot \left(\mathsf{fma}\left(-0.5, {\pi}^{2} \cdot t_0, {\pi}^{5} \cdot 0.041666666666666664\right) - 0.008333333333333333 \cdot {\pi}^{5}\right)\right)\right)}
\end{array}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 4: 87.9% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell + \frac{-1}{F \cdot \left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{{\pi}^{3} \cdot 0.3333333333333333}}\right)} \end{array} \]
(FPCore (F l)
 :precision binary64
 (+
  (* PI l)
  (/
   -1.0
   (*
    F
    (-
     (/ F (* PI l))
     (/ F (/ (/ (pow PI 2.0) l) (* (pow PI 3.0) 0.3333333333333333))))))))
double code(double F, double l) {
	return (((double) M_PI) * l) + (-1.0 / (F * ((F / (((double) M_PI) * l)) - (F / ((pow(((double) M_PI), 2.0) / l) / (pow(((double) M_PI), 3.0) * 0.3333333333333333))))));
}
public static double code(double F, double l) {
	return (Math.PI * l) + (-1.0 / (F * ((F / (Math.PI * l)) - (F / ((Math.pow(Math.PI, 2.0) / l) / (Math.pow(Math.PI, 3.0) * 0.3333333333333333))))));
}
def code(F, l):
	return (math.pi * l) + (-1.0 / (F * ((F / (math.pi * l)) - (F / ((math.pow(math.pi, 2.0) / l) / (math.pow(math.pi, 3.0) * 0.3333333333333333))))))
function code(F, l)
	return Float64(Float64(pi * l) + Float64(-1.0 / Float64(F * Float64(Float64(F / Float64(pi * l)) - Float64(F / Float64(Float64((pi ^ 2.0) / l) / Float64((pi ^ 3.0) * 0.3333333333333333)))))))
end
function tmp = code(F, l)
	tmp = (pi * l) + (-1.0 / (F * ((F / (pi * l)) - (F / (((pi ^ 2.0) / l) / ((pi ^ 3.0) * 0.3333333333333333))))));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] + N[(-1.0 / N[(F * N[(N[(F / N[(Pi * l), $MachinePrecision]), $MachinePrecision] - N[(F / N[(N[(N[Power[Pi, 2.0], $MachinePrecision] / l), $MachinePrecision] / N[(N[Power[Pi, 3.0], $MachinePrecision] * 0.3333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell + \frac{-1}{F \cdot \left(\frac{F}{\pi \cdot \ell} - \frac{F}{\frac{\frac{{\pi}^{2}}{\ell}}{{\pi}^{3} \cdot 0.3333333333333333}}\right)}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 5: 78.9% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\pi \cdot \ell \leq 10^{-16}:\\ \;\;\;\;\pi \cdot \ell - \frac{\frac{\ell}{F}}{\frac{F}{\pi}}\\ \mathbf{else}:\\ \;\;\;\;\pi \cdot \ell - \frac{\tan \left(\pi \cdot \ell\right)}{F \cdot F}\\ \end{array} \end{array} \]
(FPCore (F l)
 :precision binary64
 (if (<= (* PI l) 1e-16)
   (- (* PI l) (/ (/ l F) (/ F PI)))
   (- (* PI l) (/ (tan (* PI l)) (* F F)))))
double code(double F, double l) {
	double tmp;
	if ((((double) M_PI) * l) <= 1e-16) {
		tmp = (((double) M_PI) * l) - ((l / F) / (F / ((double) M_PI)));
	} else {
		tmp = (((double) M_PI) * l) - (tan((((double) M_PI) * l)) / (F * F));
	}
	return tmp;
}
public static double code(double F, double l) {
	double tmp;
	if ((Math.PI * l) <= 1e-16) {
		tmp = (Math.PI * l) - ((l / F) / (F / Math.PI));
	} else {
		tmp = (Math.PI * l) - (Math.tan((Math.PI * l)) / (F * F));
	}
	return tmp;
}
def code(F, l):
	tmp = 0
	if (math.pi * l) <= 1e-16:
		tmp = (math.pi * l) - ((l / F) / (F / math.pi))
	else:
		tmp = (math.pi * l) - (math.tan((math.pi * l)) / (F * F))
	return tmp
function code(F, l)
	tmp = 0.0
	if (Float64(pi * l) <= 1e-16)
		tmp = Float64(Float64(pi * l) - Float64(Float64(l / F) / Float64(F / pi)));
	else
		tmp = Float64(Float64(pi * l) - Float64(tan(Float64(pi * l)) / Float64(F * F)));
	end
	return tmp
end
function tmp_2 = code(F, l)
	tmp = 0.0;
	if ((pi * l) <= 1e-16)
		tmp = (pi * l) - ((l / F) / (F / pi));
	else
		tmp = (pi * l) - (tan((pi * l)) / (F * F));
	end
	tmp_2 = tmp;
end
code[F_, l_] := If[LessEqual[N[(Pi * l), $MachinePrecision], 1e-16], N[(N[(Pi * l), $MachinePrecision] - N[(N[(l / F), $MachinePrecision] / N[(F / Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(Pi * l), $MachinePrecision] - N[(N[Tan[N[(Pi * l), $MachinePrecision]], $MachinePrecision] / N[(F * F), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\pi \cdot \ell \leq 10^{-16}:\\
\;\;\;\;\pi \cdot \ell - \frac{\frac{\ell}{F}}{\frac{F}{\pi}}\\

\mathbf{else}:\\
\;\;\;\;\pi \cdot \ell - \frac{\tan \left(\pi \cdot \ell\right)}{F \cdot F}\\


\end{array}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 6: 82.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell + \frac{-1}{F \cdot \frac{F}{\tan \left(\pi \cdot \ell\right)}} \end{array} \]
(FPCore (F l)
 :precision binary64
 (+ (* PI l) (/ -1.0 (* F (/ F (tan (* PI l)))))))
double code(double F, double l) {
	return (((double) M_PI) * l) + (-1.0 / (F * (F / tan((((double) M_PI) * l)))));
}
public static double code(double F, double l) {
	return (Math.PI * l) + (-1.0 / (F * (F / Math.tan((Math.PI * l)))));
}
def code(F, l):
	return (math.pi * l) + (-1.0 / (F * (F / math.tan((math.pi * l)))))
function code(F, l)
	return Float64(Float64(pi * l) + Float64(-1.0 / Float64(F * Float64(F / tan(Float64(pi * l))))))
end
function tmp = code(F, l)
	tmp = (pi * l) + (-1.0 / (F * (F / tan((pi * l)))));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] + N[(-1.0 / N[(F * N[(F / N[Tan[N[(Pi * l), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell + \frac{-1}{F \cdot \frac{F}{\tan \left(\pi \cdot \ell\right)}}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 7: 82.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell - \frac{\frac{\tan \left(\pi \cdot \ell\right)}{F}}{F} \end{array} \]
(FPCore (F l) :precision binary64 (- (* PI l) (/ (/ (tan (* PI l)) F) F)))
double code(double F, double l) {
	return (((double) M_PI) * l) - ((tan((((double) M_PI) * l)) / F) / F);
}
public static double code(double F, double l) {
	return (Math.PI * l) - ((Math.tan((Math.PI * l)) / F) / F);
}
def code(F, l):
	return (math.pi * l) - ((math.tan((math.pi * l)) / F) / F)
function code(F, l)
	return Float64(Float64(pi * l) - Float64(Float64(tan(Float64(pi * l)) / F) / F))
end
function tmp = code(F, l)
	tmp = (pi * l) - ((tan((pi * l)) / F) / F);
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] - N[(N[(N[Tan[N[(Pi * l), $MachinePrecision]], $MachinePrecision] / F), $MachinePrecision] / F), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell - \frac{\frac{\tan \left(\pi \cdot \ell\right)}{F}}{F}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 8: 74.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell - \frac{\ell}{F} \cdot \frac{\pi}{F} \end{array} \]
(FPCore (F l) :precision binary64 (- (* PI l) (* (/ l F) (/ PI F))))
double code(double F, double l) {
	return (((double) M_PI) * l) - ((l / F) * (((double) M_PI) / F));
}
public static double code(double F, double l) {
	return (Math.PI * l) - ((l / F) * (Math.PI / F));
}
def code(F, l):
	return (math.pi * l) - ((l / F) * (math.pi / F))
function code(F, l)
	return Float64(Float64(pi * l) - Float64(Float64(l / F) * Float64(pi / F)))
end
function tmp = code(F, l)
	tmp = (pi * l) - ((l / F) * (pi / F));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] - N[(N[(l / F), $MachinePrecision] * N[(Pi / F), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell - \frac{\ell}{F} \cdot \frac{\pi}{F}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Alternative 9: 74.8% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \pi \cdot \ell - \frac{\frac{\ell}{F}}{\frac{F}{\pi}} \end{array} \]
(FPCore (F l) :precision binary64 (- (* PI l) (/ (/ l F) (/ F PI))))
double code(double F, double l) {
	return (((double) M_PI) * l) - ((l / F) / (F / ((double) M_PI)));
}
public static double code(double F, double l) {
	return (Math.PI * l) - ((l / F) / (F / Math.PI));
}
def code(F, l):
	return (math.pi * l) - ((l / F) / (F / math.pi))
function code(F, l)
	return Float64(Float64(pi * l) - Float64(Float64(l / F) / Float64(F / pi)))
end
function tmp = code(F, l)
	tmp = (pi * l) - ((l / F) / (F / pi));
end
code[F_, l_] := N[(N[(Pi * l), $MachinePrecision] - N[(N[(l / F), $MachinePrecision] / N[(F / Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\pi \cdot \ell - \frac{\frac{\ell}{F}}{\frac{F}{\pi}}
\end{array}
Derivation
    &prev;&pcontext;&pcontext2;&ctx;
  1. Add Preprocessing

Reproduce

?
herbie shell --seed 2024010 
(FPCore (F l)
  :name "VandenBroeck and Keller, Equation (6)"
  :precision binary64
  (- (* PI l) (* (/ 1.0 (* F F)) (tan (* PI l)))))