VandenBroeck and Keller, Equation (20)

Percentage Accurate: 6.7% → 99.0%
Time: 10.6s
Alternatives: 12
Speedup: 4.8×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\pi}{4} \cdot f\\ t_1 := e^{t\_0}\\ t_2 := e^{-t\_0}\\ -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{t\_1 + t\_2}{t\_1 - t\_2}\right) \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (* (/ PI 4.0) f)) (t_1 (exp t_0)) (t_2 (exp (- t_0))))
   (- (* (/ 1.0 (/ PI 4.0)) (log (/ (+ t_1 t_2) (- t_1 t_2)))))))
double code(double f) {
	double t_0 = (((double) M_PI) / 4.0) * f;
	double t_1 = exp(t_0);
	double t_2 = exp(-t_0);
	return -((1.0 / (((double) M_PI) / 4.0)) * log(((t_1 + t_2) / (t_1 - t_2))));
}
public static double code(double f) {
	double t_0 = (Math.PI / 4.0) * f;
	double t_1 = Math.exp(t_0);
	double t_2 = Math.exp(-t_0);
	return -((1.0 / (Math.PI / 4.0)) * Math.log(((t_1 + t_2) / (t_1 - t_2))));
}
def code(f):
	t_0 = (math.pi / 4.0) * f
	t_1 = math.exp(t_0)
	t_2 = math.exp(-t_0)
	return -((1.0 / (math.pi / 4.0)) * math.log(((t_1 + t_2) / (t_1 - t_2))))
function code(f)
	t_0 = Float64(Float64(pi / 4.0) * f)
	t_1 = exp(t_0)
	t_2 = exp(Float64(-t_0))
	return Float64(-Float64(Float64(1.0 / Float64(pi / 4.0)) * log(Float64(Float64(t_1 + t_2) / Float64(t_1 - t_2)))))
end
function tmp = code(f)
	t_0 = (pi / 4.0) * f;
	t_1 = exp(t_0);
	t_2 = exp(-t_0);
	tmp = -((1.0 / (pi / 4.0)) * log(((t_1 + t_2) / (t_1 - t_2))));
end
code[f_] := Block[{t$95$0 = N[(N[(Pi / 4.0), $MachinePrecision] * f), $MachinePrecision]}, Block[{t$95$1 = N[Exp[t$95$0], $MachinePrecision]}, Block[{t$95$2 = N[Exp[(-t$95$0)], $MachinePrecision]}, (-N[(N[(1.0 / N[(Pi / 4.0), $MachinePrecision]), $MachinePrecision] * N[Log[N[(N[(t$95$1 + t$95$2), $MachinePrecision] / N[(t$95$1 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision])]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\pi}{4} \cdot f\\
t_1 := e^{t\_0}\\
t_2 := e^{-t\_0}\\
-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{t\_1 + t\_2}{t\_1 - t\_2}\right)
\end{array}
\end{array}

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: 6.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\pi}{4} \cdot f\\ t_1 := e^{t\_0}\\ t_2 := e^{-t\_0}\\ -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{t\_1 + t\_2}{t\_1 - t\_2}\right) \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (* (/ PI 4.0) f)) (t_1 (exp t_0)) (t_2 (exp (- t_0))))
   (- (* (/ 1.0 (/ PI 4.0)) (log (/ (+ t_1 t_2) (- t_1 t_2)))))))
double code(double f) {
	double t_0 = (((double) M_PI) / 4.0) * f;
	double t_1 = exp(t_0);
	double t_2 = exp(-t_0);
	return -((1.0 / (((double) M_PI) / 4.0)) * log(((t_1 + t_2) / (t_1 - t_2))));
}
public static double code(double f) {
	double t_0 = (Math.PI / 4.0) * f;
	double t_1 = Math.exp(t_0);
	double t_2 = Math.exp(-t_0);
	return -((1.0 / (Math.PI / 4.0)) * Math.log(((t_1 + t_2) / (t_1 - t_2))));
}
def code(f):
	t_0 = (math.pi / 4.0) * f
	t_1 = math.exp(t_0)
	t_2 = math.exp(-t_0)
	return -((1.0 / (math.pi / 4.0)) * math.log(((t_1 + t_2) / (t_1 - t_2))))
function code(f)
	t_0 = Float64(Float64(pi / 4.0) * f)
	t_1 = exp(t_0)
	t_2 = exp(Float64(-t_0))
	return Float64(-Float64(Float64(1.0 / Float64(pi / 4.0)) * log(Float64(Float64(t_1 + t_2) / Float64(t_1 - t_2)))))
end
function tmp = code(f)
	t_0 = (pi / 4.0) * f;
	t_1 = exp(t_0);
	t_2 = exp(-t_0);
	tmp = -((1.0 / (pi / 4.0)) * log(((t_1 + t_2) / (t_1 - t_2))));
end
code[f_] := Block[{t$95$0 = N[(N[(Pi / 4.0), $MachinePrecision] * f), $MachinePrecision]}, Block[{t$95$1 = N[Exp[t$95$0], $MachinePrecision]}, Block[{t$95$2 = N[Exp[(-t$95$0)], $MachinePrecision]}, (-N[(N[(1.0 / N[(Pi / 4.0), $MachinePrecision]), $MachinePrecision] * N[Log[N[(N[(t$95$1 + t$95$2), $MachinePrecision] / N[(t$95$1 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision])]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\pi}{4} \cdot f\\
t_1 := e^{t\_0}\\
t_2 := e^{-t\_0}\\
-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{t\_1 + t\_2}{t\_1 - t\_2}\right)
\end{array}
\end{array}

Alternative 1: 99.0% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, 0.0026041666666666665, \left(\pi \cdot \pi\right) \cdot 0.03125\right), f, \pi \cdot 0.25\right), f, 1\right)\\ t_1 := \left(\pi \cdot f\right) \cdot -0.25\\ t_2 := e^{t\_1}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0
         (fma
          (fma
           (fma
            (* (* (* PI PI) PI) f)
            0.0026041666666666665
            (* (* PI PI) 0.03125))
           f
           (* PI 0.25))
          f
          1.0))
        (t_1 (* (* PI f) -0.25))
        (t_2 (exp t_1)))
   (if (<= f 23.5)
     (* -4.0 (/ (log (/ (cosh t_1) (sinh (* (* 0.25 f) PI)))) PI))
     (* (/ 4.0 PI) (- (log (/ (+ t_0 t_2) (- t_0 t_2))))))))
double code(double f) {
	double t_0 = fma(fma(fma((((((double) M_PI) * ((double) M_PI)) * ((double) M_PI)) * f), 0.0026041666666666665, ((((double) M_PI) * ((double) M_PI)) * 0.03125)), f, (((double) M_PI) * 0.25)), f, 1.0);
	double t_1 = (((double) M_PI) * f) * -0.25;
	double t_2 = exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = (4.0 / ((double) M_PI)) * -log(((t_0 + t_2) / (t_0 - t_2)));
	}
	return tmp;
}
function code(f)
	t_0 = fma(fma(fma(Float64(Float64(Float64(pi * pi) * pi) * f), 0.0026041666666666665, Float64(Float64(pi * pi) * 0.03125)), f, Float64(pi * 0.25)), f, 1.0)
	t_1 = Float64(Float64(pi * f) * -0.25)
	t_2 = exp(t_1)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(t_1) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(Float64(4.0 / pi) * Float64(-log(Float64(Float64(t_0 + t_2) / Float64(t_0 - t_2)))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[(N[(N[(N[(N[(N[(Pi * Pi), $MachinePrecision] * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.0026041666666666665 + N[(N[(Pi * Pi), $MachinePrecision] * 0.03125), $MachinePrecision]), $MachinePrecision] * f + N[(Pi * 0.25), $MachinePrecision]), $MachinePrecision] * f + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]}, Block[{t$95$2 = N[Exp[t$95$1], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[t$95$1], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(4.0 / Pi), $MachinePrecision] * (-N[Log[N[(N[(t$95$0 + t$95$2), $MachinePrecision] / N[(t$95$0 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, 0.0026041666666666665, \left(\pi \cdot \pi\right) \cdot 0.03125\right), f, \pi \cdot 0.25\right), f, 1\right)\\
t_1 := \left(\pi \cdot f\right) \cdot -0.25\\
t_2 := e^{t\_1}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Applied rewrites8.0%

      \[\leadsto \color{blue}{\frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right)} \]
    9. Taylor expanded in f around 0

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right)\right)} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    10. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right) + \color{blue}{1}\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. *-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right) \cdot f + 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-fma.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right), \color{blue}{f}, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    11. Applied rewrites5.9%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, 0.0026041666666666665, \left(\pi \cdot \pi\right) \cdot 0.03125\right), f, \pi \cdot 0.25\right), f, 1\right)} + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    12. Taylor expanded in f around 0

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, \frac{1}{384}, \left(\pi \cdot \pi\right) \cdot \frac{1}{32}\right), f, \pi \cdot \frac{1}{4}\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right)\right)} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    13. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, \frac{1}{384}, \left(\pi \cdot \pi\right) \cdot \frac{1}{32}\right), f, \pi \cdot \frac{1}{4}\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right) + \color{blue}{1}\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. *-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, \frac{1}{384}, \left(\pi \cdot \pi\right) \cdot \frac{1}{32}\right), f, \pi \cdot \frac{1}{4}\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right)\right) \cdot f + 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-fma.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, \frac{1}{384}, \left(\pi \cdot \pi\right) \cdot \frac{1}{32}\right), f, \pi \cdot \frac{1}{4}\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) + f \cdot \left(\frac{1}{384} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{3}\right) + \frac{1}{32} \cdot {\mathsf{PI}\left(\right)}^{2}\right), \color{blue}{f}, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    14. Applied rewrites8.2%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, 0.0026041666666666665, \left(\pi \cdot \pi\right) \cdot 0.03125\right), f, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot \pi\right) \cdot f, 0.0026041666666666665, \left(\pi \cdot \pi\right) \cdot 0.03125\right), f, \pi \cdot 0.25\right), f, 1\right)} - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 99.0% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right)\\ t_1 := \left(\pi \cdot f\right) \cdot -0.25\\ t_2 := e^{t\_1}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\log \left({\left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)}^{\left(-\frac{4}{\pi}\right)}\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (fma (fma (* (* PI PI) f) 0.03125 (* PI 0.25)) f 1.0))
        (t_1 (* (* PI f) -0.25))
        (t_2 (exp t_1)))
   (if (<= f 23.5)
     (* -4.0 (/ (log (/ (cosh t_1) (sinh (* (* 0.25 f) PI)))) PI))
     (log (pow (/ (+ t_0 t_2) (- t_0 t_2)) (- (/ 4.0 PI)))))))
double code(double f) {
	double t_0 = fma(fma(((((double) M_PI) * ((double) M_PI)) * f), 0.03125, (((double) M_PI) * 0.25)), f, 1.0);
	double t_1 = (((double) M_PI) * f) * -0.25;
	double t_2 = exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = log(pow(((t_0 + t_2) / (t_0 - t_2)), -(4.0 / ((double) M_PI))));
	}
	return tmp;
}
function code(f)
	t_0 = fma(fma(Float64(Float64(pi * pi) * f), 0.03125, Float64(pi * 0.25)), f, 1.0)
	t_1 = Float64(Float64(pi * f) * -0.25)
	t_2 = exp(t_1)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(t_1) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = log((Float64(Float64(t_0 + t_2) / Float64(t_0 - t_2)) ^ Float64(-Float64(4.0 / pi))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[(N[(N[(N[(Pi * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.03125 + N[(Pi * 0.25), $MachinePrecision]), $MachinePrecision] * f + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]}, Block[{t$95$2 = N[Exp[t$95$1], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[t$95$1], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[Log[N[Power[N[(N[(t$95$0 + t$95$2), $MachinePrecision] / N[(t$95$0 - t$95$2), $MachinePrecision]), $MachinePrecision], (-N[(4.0 / Pi), $MachinePrecision])], $MachinePrecision]], $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right)\\
t_1 := \left(\pi \cdot f\right) \cdot -0.25\\
t_2 := e^{t\_1}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\log \left({\left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)}^{\left(-\frac{4}{\pi}\right)}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Applied rewrites8.0%

      \[\leadsto \color{blue}{\log \left({\left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)}^{\left(-\frac{4}{\pi}\right)}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 99.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right)\\ t_1 := \left(\pi \cdot f\right) \cdot -0.25\\ t_2 := e^{t\_1}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (fma (fma (* (* PI PI) f) 0.03125 (* PI 0.25)) f 1.0))
        (t_1 (* (* PI f) -0.25))
        (t_2 (exp t_1)))
   (if (<= f 23.5)
     (* -4.0 (/ (log (/ (cosh t_1) (sinh (* (* 0.25 f) PI)))) PI))
     (* (/ 4.0 PI) (- (log (/ (+ t_0 t_2) (- t_0 t_2))))))))
double code(double f) {
	double t_0 = fma(fma(((((double) M_PI) * ((double) M_PI)) * f), 0.03125, (((double) M_PI) * 0.25)), f, 1.0);
	double t_1 = (((double) M_PI) * f) * -0.25;
	double t_2 = exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = (4.0 / ((double) M_PI)) * -log(((t_0 + t_2) / (t_0 - t_2)));
	}
	return tmp;
}
function code(f)
	t_0 = fma(fma(Float64(Float64(pi * pi) * f), 0.03125, Float64(pi * 0.25)), f, 1.0)
	t_1 = Float64(Float64(pi * f) * -0.25)
	t_2 = exp(t_1)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(t_1) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(Float64(4.0 / pi) * Float64(-log(Float64(Float64(t_0 + t_2) / Float64(t_0 - t_2)))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[(N[(N[(N[(Pi * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.03125 + N[(Pi * 0.25), $MachinePrecision]), $MachinePrecision] * f + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]}, Block[{t$95$2 = N[Exp[t$95$1], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[t$95$1], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(4.0 / Pi), $MachinePrecision] * (-N[Log[N[(N[(t$95$0 + t$95$2), $MachinePrecision] / N[(t$95$0 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right)\\
t_1 := \left(\pi \cdot f\right) \cdot -0.25\\
t_2 := e^{t\_1}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Applied rewrites8.0%

      \[\leadsto \color{blue}{\frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 99.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-0.25 \cdot \left(\pi \cdot f\right)}\\ t_1 := \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;-\frac{1}{\frac{\pi}{4}} \cdot \left(-\log \left(\frac{t\_1 - t\_0}{t\_0 + t\_1}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (exp (* -0.25 (* PI f))))
        (t_1 (fma (* (* (* PI PI) f) 0.03125) f 1.0)))
   (if (<= f 23.5)
     (*
      -4.0
      (/ (log (/ (cosh (* (* PI f) -0.25)) (sinh (* (* 0.25 f) PI)))) PI))
     (- (* (/ 1.0 (/ PI 4.0)) (- (log (/ (- t_1 t_0) (+ t_0 t_1)))))))))
double code(double f) {
	double t_0 = exp((-0.25 * (((double) M_PI) * f)));
	double t_1 = fma((((((double) M_PI) * ((double) M_PI)) * f) * 0.03125), f, 1.0);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(((((double) M_PI) * f) * -0.25)) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = -((1.0 / (((double) M_PI) / 4.0)) * -log(((t_1 - t_0) / (t_0 + t_1))));
	}
	return tmp;
}
function code(f)
	t_0 = exp(Float64(-0.25 * Float64(pi * f)))
	t_1 = fma(Float64(Float64(Float64(pi * pi) * f) * 0.03125), f, 1.0)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(Float64(Float64(pi * f) * -0.25)) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(-Float64(Float64(1.0 / Float64(pi / 4.0)) * Float64(-log(Float64(Float64(t_1 - t_0) / Float64(t_0 + t_1))))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[Exp[N[(-0.25 * N[(Pi * f), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(N[(N[(Pi * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.03125), $MachinePrecision] * f + 1.0), $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], (-N[(N[(1.0 / N[(Pi / 4.0), $MachinePrecision]), $MachinePrecision] * (-N[Log[N[(N[(t$95$1 - t$95$0), $MachinePrecision] / N[(t$95$0 + t$95$1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision])]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-0.25 \cdot \left(\pi \cdot f\right)}\\
t_1 := \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;-\frac{1}{\frac{\pi}{4}} \cdot \left(-\log \left(\frac{t\_1 - t\_0}{t\_0 + t\_1}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Taylor expanded in f around inf

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left({\mathsf{PI}\left(\right)}^{2} \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. pow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. lift-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lift-*.f645.4

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    10. Applied rewrites5.4%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    11. Taylor expanded in f around inf

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left({\mathsf{PI}\left(\right)}^{2} \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. pow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. lift-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lift-*.f646.4

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    13. Applied rewrites6.4%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    14. Applied rewrites6.4%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \color{blue}{\left(-\log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-0.25 \cdot \left(\pi \cdot f\right)}}{e^{-0.25 \cdot \left(\pi \cdot f\right)} + \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 5: 99.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-0.25 \cdot \left(\pi \cdot f\right)}\\ t_1 := \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_1}{t\_1 - t\_0}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (exp (* -0.25 (* PI f))))
        (t_1 (fma (* (* (* PI PI) f) 0.03125) f 1.0)))
   (if (<= f 23.5)
     (*
      -4.0
      (/ (log (/ (cosh (* (* PI f) -0.25)) (sinh (* (* 0.25 f) PI)))) PI))
     (* (/ 4.0 PI) (- (log (/ (+ t_0 t_1) (- t_1 t_0))))))))
double code(double f) {
	double t_0 = exp((-0.25 * (((double) M_PI) * f)));
	double t_1 = fma((((((double) M_PI) * ((double) M_PI)) * f) * 0.03125), f, 1.0);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(((((double) M_PI) * f) * -0.25)) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = (4.0 / ((double) M_PI)) * -log(((t_0 + t_1) / (t_1 - t_0)));
	}
	return tmp;
}
function code(f)
	t_0 = exp(Float64(-0.25 * Float64(pi * f)))
	t_1 = fma(Float64(Float64(Float64(pi * pi) * f) * 0.03125), f, 1.0)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(Float64(Float64(pi * f) * -0.25)) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(Float64(4.0 / pi) * Float64(-log(Float64(Float64(t_0 + t_1) / Float64(t_1 - t_0)))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[Exp[N[(-0.25 * N[(Pi * f), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(N[(N[(Pi * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.03125), $MachinePrecision] * f + 1.0), $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(4.0 / Pi), $MachinePrecision] * (-N[Log[N[(N[(t$95$0 + t$95$1), $MachinePrecision] / N[(t$95$1 - t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-0.25 \cdot \left(\pi \cdot f\right)}\\
t_1 := \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_1}{t\_1 - t\_0}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Taylor expanded in f around inf

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left({\mathsf{PI}\left(\right)}^{2} \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. pow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. lift-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lift-*.f645.4

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    10. Applied rewrites5.4%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    11. Taylor expanded in f around inf

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left({\mathsf{PI}\left(\right)}^{2} \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. pow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. lift-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot \frac{1}{32}, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lift-*.f646.4

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    13. Applied rewrites6.4%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    14. Applied rewrites6.4%

      \[\leadsto \color{blue}{\frac{4}{\pi} \cdot \left(-\log \left(\frac{e^{-0.25 \cdot \left(\pi \cdot f\right)} + \mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right)}{\mathsf{fma}\left(\left(\left(\pi \cdot \pi\right) \cdot f\right) \cdot 0.03125, f, 1\right) - e^{-0.25 \cdot \left(\pi \cdot f\right)}}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 6: 99.0% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right)\\ t_1 := \left(\pi \cdot f\right) \cdot -0.25\\ t_2 := e^{t\_1}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (* (* 0.03125 (* f f)) (* PI PI)))
        (t_1 (* (* PI f) -0.25))
        (t_2 (exp t_1)))
   (if (<= f 23.5)
     (* -4.0 (/ (log (/ (cosh t_1) (sinh (* (* 0.25 f) PI)))) PI))
     (* (/ 4.0 PI) (- (log (/ (+ t_0 t_2) (- t_0 t_2))))))))
double code(double f) {
	double t_0 = (0.03125 * (f * f)) * (((double) M_PI) * ((double) M_PI));
	double t_1 = (((double) M_PI) * f) * -0.25;
	double t_2 = exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = (4.0 / ((double) M_PI)) * -log(((t_0 + t_2) / (t_0 - t_2)));
	}
	return tmp;
}
public static double code(double f) {
	double t_0 = (0.03125 * (f * f)) * (Math.PI * Math.PI);
	double t_1 = (Math.PI * f) * -0.25;
	double t_2 = Math.exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (Math.log((Math.cosh(t_1) / Math.sinh(((0.25 * f) * Math.PI)))) / Math.PI);
	} else {
		tmp = (4.0 / Math.PI) * -Math.log(((t_0 + t_2) / (t_0 - t_2)));
	}
	return tmp;
}
def code(f):
	t_0 = (0.03125 * (f * f)) * (math.pi * math.pi)
	t_1 = (math.pi * f) * -0.25
	t_2 = math.exp(t_1)
	tmp = 0
	if f <= 23.5:
		tmp = -4.0 * (math.log((math.cosh(t_1) / math.sinh(((0.25 * f) * math.pi)))) / math.pi)
	else:
		tmp = (4.0 / math.pi) * -math.log(((t_0 + t_2) / (t_0 - t_2)))
	return tmp
function code(f)
	t_0 = Float64(Float64(0.03125 * Float64(f * f)) * Float64(pi * pi))
	t_1 = Float64(Float64(pi * f) * -0.25)
	t_2 = exp(t_1)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(t_1) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(Float64(4.0 / pi) * Float64(-log(Float64(Float64(t_0 + t_2) / Float64(t_0 - t_2)))));
	end
	return tmp
end
function tmp_2 = code(f)
	t_0 = (0.03125 * (f * f)) * (pi * pi);
	t_1 = (pi * f) * -0.25;
	t_2 = exp(t_1);
	tmp = 0.0;
	if (f <= 23.5)
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * pi)))) / pi);
	else
		tmp = (4.0 / pi) * -log(((t_0 + t_2) / (t_0 - t_2)));
	end
	tmp_2 = tmp;
end
code[f_] := Block[{t$95$0 = N[(N[(0.03125 * N[(f * f), $MachinePrecision]), $MachinePrecision] * N[(Pi * Pi), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]}, Block[{t$95$2 = N[Exp[t$95$1], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[t$95$1], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(4.0 / Pi), $MachinePrecision] * (-N[Log[N[(N[(t$95$0 + t$95$2), $MachinePrecision] / N[(t$95$0 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right)\\
t_1 := \left(\pi \cdot f\right) \cdot -0.25\\
t_2 := e^{t\_1}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Applied rewrites8.0%

      \[\leadsto \color{blue}{\frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right)} \]
    9. Taylor expanded in f around inf

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\frac{1}{32} \cdot \color{blue}{\left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    10. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{\color{blue}{2}} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{\color{blue}{2}} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{2} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      4. unpow2N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot {\mathsf{PI}\left(\right)}^{2} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      5. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot {\mathsf{PI}\left(\right)}^{2} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      6. pow2N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      7. lift-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      8. lift-PI.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \mathsf{PI}\left(\right)\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      9. lift-PI.f644.2

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    11. Applied rewrites4.2%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \color{blue}{\left(\pi \cdot \pi\right)} + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    12. Taylor expanded in f around inf

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\frac{1}{32} \cdot \color{blue}{\left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    13. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{\color{blue}{2}} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{\color{blue}{2}} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{2} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      4. unpow2N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot {\mathsf{PI}\left(\right)}^{2} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      5. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot {\mathsf{PI}\left(\right)}^{2} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      6. pow2N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      7. lift-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      8. lift-PI.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{32} \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \mathsf{PI}\left(\right)\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      9. lift-PI.f642.3

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    14. Applied rewrites2.3%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \left(\pi \cdot \pi\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\left(0.03125 \cdot \left(f \cdot f\right)\right) \cdot \color{blue}{\left(\pi \cdot \pi\right)} - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 7: 99.0% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(f \cdot 0.25, \pi, 1\right)\\ t_1 := \left(\pi \cdot f\right) \cdot -0.25\\ t_2 := e^{t\_1}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (fma (* f 0.25) PI 1.0)) (t_1 (* (* PI f) -0.25)) (t_2 (exp t_1)))
   (if (<= f 23.5)
     (* -4.0 (/ (log (/ (cosh t_1) (sinh (* (* 0.25 f) PI)))) PI))
     (* (/ 4.0 PI) (- (log (/ (+ t_0 t_2) (- t_0 t_2))))))))
double code(double f) {
	double t_0 = fma((f * 0.25), ((double) M_PI), 1.0);
	double t_1 = (((double) M_PI) * f) * -0.25;
	double t_2 = exp(t_1);
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(t_1) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = (4.0 / ((double) M_PI)) * -log(((t_0 + t_2) / (t_0 - t_2)));
	}
	return tmp;
}
function code(f)
	t_0 = fma(Float64(f * 0.25), pi, 1.0)
	t_1 = Float64(Float64(pi * f) * -0.25)
	t_2 = exp(t_1)
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(t_1) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(Float64(4.0 / pi) * Float64(-log(Float64(Float64(t_0 + t_2) / Float64(t_0 - t_2)))));
	end
	return tmp
end
code[f_] := Block[{t$95$0 = N[(N[(f * 0.25), $MachinePrecision] * Pi + 1.0), $MachinePrecision]}, Block[{t$95$1 = N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]}, Block[{t$95$2 = N[Exp[t$95$1], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[t$95$1], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], N[(N[(4.0 / Pi), $MachinePrecision] * (-N[Log[N[(N[(t$95$0 + t$95$2), $MachinePrecision] / N[(t$95$0 - t$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(f \cdot 0.25, \pi, 1\right)\\
t_1 := \left(\pi \cdot f\right) \cdot -0.25\\
t_2 := e^{t\_1}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh t\_1}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;\frac{4}{\pi} \cdot \left(-\log \left(\frac{t\_0 + t\_2}{t\_0 - t\_2}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f646.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    4. Applied rewrites6.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    5. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\left(1 + f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(f \cdot \left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\left(\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f + 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \frac{1}{4} \cdot \mathsf{PI}\left(\right), \color{blue}{f}, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. lower-fma.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, f \cdot {\mathsf{PI}\left(\right)}^{2}, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      5. *-commutativeN/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      6. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, {\mathsf{PI}\left(\right)}^{2} \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      7. unpow2N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      8. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      9. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \mathsf{PI}\left(\right)\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      10. lift-PI.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      11. lower-*.f64N/A

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{32}, \left(\pi \cdot \pi\right) \cdot f, \frac{1}{4} \cdot \mathsf{PI}\left(\right)\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      12. lift-PI.f648.0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    7. Applied rewrites8.0%

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right) + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.03125, \left(\pi \cdot \pi\right) \cdot f, 0.25 \cdot \pi\right), f, 1\right)} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    8. Applied rewrites8.0%

      \[\leadsto \color{blue}{\frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right)} \]
    9. Taylor expanded in f around 0

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\color{blue}{\left(1 + \frac{1}{4} \cdot \left(f \cdot \mathsf{PI}\left(\right)\right)\right)} + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    10. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\frac{1}{4} \cdot \left(f \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. associate-*l*N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\left(\left(\frac{1}{4} \cdot f\right) \cdot \mathsf{PI}\left(\right) + 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-fma.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(\frac{1}{4} \cdot f, \color{blue}{\mathsf{PI}\left(\right)}, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      4. *-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \mathsf{PI}\left(\right), 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      5. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \mathsf{PI}\left(\right), 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, \frac{1}{32}, \pi \cdot \frac{1}{4}\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      6. lift-PI.f645.8

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    11. Applied rewrites5.8%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\color{blue}{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right)} + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot \pi\right) \cdot f, 0.03125, \pi \cdot 0.25\right), f, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    12. Taylor expanded in f around 0

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\color{blue}{\left(1 + \frac{1}{4} \cdot \left(f \cdot \mathsf{PI}\left(\right)\right)\right)} - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
    13. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\frac{1}{4} \cdot \left(f \cdot \mathsf{PI}\left(\right)\right) + \color{blue}{1}\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      2. associate-*l*N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\left(\left(\frac{1}{4} \cdot f\right) \cdot \mathsf{PI}\left(\right) + 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      3. lower-fma.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(\frac{1}{4} \cdot f, \color{blue}{\mathsf{PI}\left(\right)}, 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      4. *-commutativeN/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(f \cdot \frac{1}{4}, \mathsf{PI}\left(\right), 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      5. lower-*.f64N/A

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot \frac{1}{4}, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}{\mathsf{fma}\left(f \cdot \frac{1}{4}, \mathsf{PI}\left(\right), 1\right) - e^{\left(\pi \cdot f\right) \cdot \frac{-1}{4}}}\right)\right) \]
      6. lift-PI.f647.6

        \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right) - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
    14. Applied rewrites7.6%

      \[\leadsto \frac{4}{\pi} \cdot \left(-\log \left(\frac{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right) + e^{\left(\pi \cdot f\right) \cdot -0.25}}{\color{blue}{\mathsf{fma}\left(f \cdot 0.25, \pi, 1\right)} - e^{\left(\pi \cdot f\right) \cdot -0.25}}\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 8: 99.0% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-\frac{\pi}{4} \cdot f}\\ \mathbf{if}\;f \leq 23.5:\\ \;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\ \mathbf{else}:\\ \;\;\;\;-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{1 + t\_0}{1 - t\_0}\right)\\ \end{array} \end{array} \]
(FPCore (f)
 :precision binary64
 (let* ((t_0 (exp (- (* (/ PI 4.0) f)))))
   (if (<= f 23.5)
     (*
      -4.0
      (/ (log (/ (cosh (* (* PI f) -0.25)) (sinh (* (* 0.25 f) PI)))) PI))
     (- (* (/ 1.0 (/ PI 4.0)) (log (/ (+ 1.0 t_0) (- 1.0 t_0))))))))
double code(double f) {
	double t_0 = exp(-((((double) M_PI) / 4.0) * f));
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (log((cosh(((((double) M_PI) * f) * -0.25)) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
	} else {
		tmp = -((1.0 / (((double) M_PI) / 4.0)) * log(((1.0 + t_0) / (1.0 - t_0))));
	}
	return tmp;
}
public static double code(double f) {
	double t_0 = Math.exp(-((Math.PI / 4.0) * f));
	double tmp;
	if (f <= 23.5) {
		tmp = -4.0 * (Math.log((Math.cosh(((Math.PI * f) * -0.25)) / Math.sinh(((0.25 * f) * Math.PI)))) / Math.PI);
	} else {
		tmp = -((1.0 / (Math.PI / 4.0)) * Math.log(((1.0 + t_0) / (1.0 - t_0))));
	}
	return tmp;
}
def code(f):
	t_0 = math.exp(-((math.pi / 4.0) * f))
	tmp = 0
	if f <= 23.5:
		tmp = -4.0 * (math.log((math.cosh(((math.pi * f) * -0.25)) / math.sinh(((0.25 * f) * math.pi)))) / math.pi)
	else:
		tmp = -((1.0 / (math.pi / 4.0)) * math.log(((1.0 + t_0) / (1.0 - t_0))))
	return tmp
function code(f)
	t_0 = exp(Float64(-Float64(Float64(pi / 4.0) * f)))
	tmp = 0.0
	if (f <= 23.5)
		tmp = Float64(-4.0 * Float64(log(Float64(cosh(Float64(Float64(pi * f) * -0.25)) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi));
	else
		tmp = Float64(-Float64(Float64(1.0 / Float64(pi / 4.0)) * log(Float64(Float64(1.0 + t_0) / Float64(1.0 - t_0)))));
	end
	return tmp
end
function tmp_2 = code(f)
	t_0 = exp(-((pi / 4.0) * f));
	tmp = 0.0;
	if (f <= 23.5)
		tmp = -4.0 * (log((cosh(((pi * f) * -0.25)) / sinh(((0.25 * f) * pi)))) / pi);
	else
		tmp = -((1.0 / (pi / 4.0)) * log(((1.0 + t_0) / (1.0 - t_0))));
	end
	tmp_2 = tmp;
end
code[f_] := Block[{t$95$0 = N[Exp[(-N[(N[(Pi / 4.0), $MachinePrecision] * f), $MachinePrecision])], $MachinePrecision]}, If[LessEqual[f, 23.5], N[(-4.0 * N[(N[Log[N[(N[Cosh[N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision], (-N[(N[(1.0 / N[(Pi / 4.0), $MachinePrecision]), $MachinePrecision] * N[Log[N[(N[(1.0 + t$95$0), $MachinePrecision] / N[(1.0 - t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision])]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-\frac{\pi}{4} \cdot f}\\
\mathbf{if}\;f \leq 23.5:\\
\;\;\;\;-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}\\

\mathbf{else}:\\
\;\;\;\;-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{1 + t\_0}{1 - t\_0}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if f < 23.5

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Applied rewrites96.8%

      \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
    3. Applied rewrites96.8%

      \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]

    if 23.5 < f

    1. Initial program 6.7%

      \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    2. Taylor expanded in f around 0

      \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{1} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
    3. Step-by-step derivation
      1. Applied rewrites5.3%

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{\color{blue}{1} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. Taylor expanded in f around 0

        \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{1 + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{1} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      3. Step-by-step derivation
        1. Applied rewrites6.4%

          \[\leadsto -\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{1 + e^{-\frac{\pi}{4} \cdot f}}{\color{blue}{1} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      4. Recombined 2 regimes into one program.
      5. Add Preprocessing

      Alternative 9: 96.8% accurate, 1.8× speedup?

      \[\begin{array}{l} \\ -4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi} \end{array} \]
      (FPCore (f)
       :precision binary64
       (* -4.0 (/ (log (/ (cosh (* (* PI f) -0.25)) (sinh (* (* 0.25 f) PI)))) PI)))
      double code(double f) {
      	return -4.0 * (log((cosh(((((double) M_PI) * f) * -0.25)) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
      }
      
      public static double code(double f) {
      	return -4.0 * (Math.log((Math.cosh(((Math.PI * f) * -0.25)) / Math.sinh(((0.25 * f) * Math.PI)))) / Math.PI);
      }
      
      def code(f):
      	return -4.0 * (math.log((math.cosh(((math.pi * f) * -0.25)) / math.sinh(((0.25 * f) * math.pi)))) / math.pi)
      
      function code(f)
      	return Float64(-4.0 * Float64(log(Float64(cosh(Float64(Float64(pi * f) * -0.25)) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi))
      end
      
      function tmp = code(f)
      	tmp = -4.0 * (log((cosh(((pi * f) * -0.25)) / sinh(((0.25 * f) * pi)))) / pi);
      end
      
      code[f_] := N[(-4.0 * N[(N[Log[N[(N[Cosh[N[(N[(Pi * f), $MachinePrecision] * -0.25), $MachinePrecision]], $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}
      \end{array}
      
      Derivation
      1. Initial program 6.7%

        \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. Applied rewrites96.8%

        \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
      3. Applied rewrites96.8%

        \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]
      4. Add Preprocessing

      Alternative 10: 96.2% accurate, 1.9× speedup?

      \[\begin{array}{l} \\ -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(0.03125 \cdot \left(f \cdot f\right), \pi \cdot \pi, 1\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi} \end{array} \]
      (FPCore (f)
       :precision binary64
       (*
        -4.0
        (/
         (log (/ (fma (* 0.03125 (* f f)) (* PI PI) 1.0) (sinh (* (* 0.25 f) PI))))
         PI)))
      double code(double f) {
      	return -4.0 * (log((fma((0.03125 * (f * f)), (((double) M_PI) * ((double) M_PI)), 1.0) / sinh(((0.25 * f) * ((double) M_PI))))) / ((double) M_PI));
      }
      
      function code(f)
      	return Float64(-4.0 * Float64(log(Float64(fma(Float64(0.03125 * Float64(f * f)), Float64(pi * pi), 1.0) / sinh(Float64(Float64(0.25 * f) * pi)))) / pi))
      end
      
      code[f_] := N[(-4.0 * N[(N[Log[N[(N[(N[(0.03125 * N[(f * f), $MachinePrecision]), $MachinePrecision] * N[(Pi * Pi), $MachinePrecision] + 1.0), $MachinePrecision] / N[Sinh[N[(N[(0.25 * f), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(0.03125 \cdot \left(f \cdot f\right), \pi \cdot \pi, 1\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}
      \end{array}
      
      Derivation
      1. Initial program 6.7%

        \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. Applied rewrites96.8%

        \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
      3. Applied rewrites96.8%

        \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot f\right) \cdot -0.25\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi}} \]
      4. Taylor expanded in f around 0

        \[\leadsto -4 \cdot \frac{\log \left(\frac{\color{blue}{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
      5. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        2. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        3. metadata-evalN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        4. distribute-lft-neg-inN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        5. cosh-neg-revN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\color{blue}{1} + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        6. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        7. associate-*l*N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{1 + \frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        8. +-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\frac{1}{32} \cdot \left({f}^{2} \cdot {\mathsf{PI}\left(\right)}^{2}\right) + \color{blue}{1}}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        9. associate-*r*N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\left(\frac{1}{32} \cdot {f}^{2}\right) \cdot {\mathsf{PI}\left(\right)}^{2} + 1}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        10. lower-fma.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot {f}^{2}, \color{blue}{{\mathsf{PI}\left(\right)}^{2}}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        11. lower-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot {f}^{2}, {\color{blue}{\mathsf{PI}\left(\right)}}^{2}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        12. unpow2N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot f\right), {\mathsf{PI}\left(\right)}^{2}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        13. lower-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot f\right), {\mathsf{PI}\left(\right)}^{2}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        14. pow2N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot f\right), \mathsf{PI}\left(\right) \cdot \color{blue}{\mathsf{PI}\left(\right)}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        15. lift-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot f\right), \mathsf{PI}\left(\right) \cdot \color{blue}{\mathsf{PI}\left(\right)}, 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        16. lift-PI.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(\frac{1}{32} \cdot \left(f \cdot f\right), \pi \cdot \mathsf{PI}\left(\right), 1\right)}{\sinh \left(\left(\frac{1}{4} \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
        17. lift-PI.f6496.2

          \[\leadsto -4 \cdot \frac{\log \left(\frac{\mathsf{fma}\left(0.03125 \cdot \left(f \cdot f\right), \pi \cdot \pi, 1\right)}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
      6. Applied rewrites96.2%

        \[\leadsto -4 \cdot \frac{\log \left(\frac{\color{blue}{\mathsf{fma}\left(0.03125 \cdot \left(f \cdot f\right), \pi \cdot \pi, 1\right)}}{\sinh \left(\left(0.25 \cdot f\right) \cdot \pi\right)}\right)}{\pi} \]
      7. Add Preprocessing

      Alternative 11: 95.8% accurate, 2.2× speedup?

      \[\begin{array}{l} \\ -4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot 0.25\right) \cdot f\right)}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}\right)}{\pi} \end{array} \]
      (FPCore (f)
       :precision binary64
       (* -4.0 (/ (log (/ (cosh (* (* PI 0.25) f)) (* (* (* 0.5 PI) f) 0.5))) PI)))
      double code(double f) {
      	return -4.0 * (log((cosh(((((double) M_PI) * 0.25) * f)) / (((0.5 * ((double) M_PI)) * f) * 0.5))) / ((double) M_PI));
      }
      
      public static double code(double f) {
      	return -4.0 * (Math.log((Math.cosh(((Math.PI * 0.25) * f)) / (((0.5 * Math.PI) * f) * 0.5))) / Math.PI);
      }
      
      def code(f):
      	return -4.0 * (math.log((math.cosh(((math.pi * 0.25) * f)) / (((0.5 * math.pi) * f) * 0.5))) / math.pi)
      
      function code(f)
      	return Float64(-4.0 * Float64(log(Float64(cosh(Float64(Float64(pi * 0.25) * f)) / Float64(Float64(Float64(0.5 * pi) * f) * 0.5))) / pi))
      end
      
      function tmp = code(f)
      	tmp = -4.0 * (log((cosh(((pi * 0.25) * f)) / (((0.5 * pi) * f) * 0.5))) / pi);
      end
      
      code[f_] := N[(-4.0 * N[(N[Log[N[(N[Cosh[N[(N[(Pi * 0.25), $MachinePrecision] * f), $MachinePrecision]], $MachinePrecision] / N[(N[(N[(0.5 * Pi), $MachinePrecision] * f), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      -4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot 0.25\right) \cdot f\right)}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}\right)}{\pi}
      \end{array}
      
      Derivation
      1. Initial program 6.7%

        \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. Applied rewrites96.8%

        \[\leadsto -\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\sinh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}\right)}{\pi}} \]
      3. Taylor expanded in f around 0

        \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\color{blue}{\frac{1}{2} \cdot \left(f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)\right)\right)}}\right)}{\pi} \]
      4. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\frac{1}{2}}}\right)}{\pi} \]
        2. lower-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(f \cdot \left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \color{blue}{\frac{1}{2}}}\right)}{\pi} \]
        3. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        4. lower-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        5. distribute-rgt-out--N/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot \left(\frac{1}{4} - \frac{-1}{4}\right)\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        6. metadata-evalN/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot \frac{1}{2}\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        7. *-commutativeN/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        8. lower-*.f64N/A

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \mathsf{PI}\left(\right)\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        9. lift-PI.f6495.8

          \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}\right)}{\pi} \]
      5. Applied rewrites95.8%

        \[\leadsto -4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\color{blue}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}}\right)}{\pi} \]
      6. Step-by-step derivation
        1. lift-neg.f64N/A

          \[\leadsto \color{blue}{\mathsf{neg}\left(4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \pi\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi}\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \mathsf{neg}\left(\color{blue}{4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \pi\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi}}\right) \]
        3. distribute-lft-neg-inN/A

          \[\leadsto \color{blue}{\left(\mathsf{neg}\left(4\right)\right) \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \pi\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi}} \]
        4. metadata-evalN/A

          \[\leadsto \color{blue}{-4} \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(\frac{1}{4} \cdot \pi\right) \cdot f\right)}{\left(\left(\frac{1}{2} \cdot \pi\right) \cdot f\right) \cdot \frac{1}{2}}\right)}{\pi} \]
        5. lower-*.f6495.8

          \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(1 \cdot \frac{\cosh \left(\left(0.25 \cdot \pi\right) \cdot f\right)}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}\right)}{\pi}} \]
      7. Applied rewrites95.8%

        \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{\cosh \left(\left(\pi \cdot 0.25\right) \cdot f\right)}{\left(\left(0.5 \cdot \pi\right) \cdot f\right) \cdot 0.5}\right)}{\pi}} \]
      8. Add Preprocessing

      Alternative 12: 95.8% accurate, 4.8× speedup?

      \[\begin{array}{l} \\ \frac{\log \left(\frac{4}{\pi \cdot f}\right)}{\pi} \cdot -4 \end{array} \]
      (FPCore (f) :precision binary64 (* (/ (log (/ 4.0 (* PI f))) PI) -4.0))
      double code(double f) {
      	return (log((4.0 / (((double) M_PI) * f))) / ((double) M_PI)) * -4.0;
      }
      
      public static double code(double f) {
      	return (Math.log((4.0 / (Math.PI * f))) / Math.PI) * -4.0;
      }
      
      def code(f):
      	return (math.log((4.0 / (math.pi * f))) / math.pi) * -4.0
      
      function code(f)
      	return Float64(Float64(log(Float64(4.0 / Float64(pi * f))) / pi) * -4.0)
      end
      
      function tmp = code(f)
      	tmp = (log((4.0 / (pi * f))) / pi) * -4.0;
      end
      
      code[f_] := N[(N[(N[Log[N[(4.0 / N[(Pi * f), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / Pi), $MachinePrecision] * -4.0), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\log \left(\frac{4}{\pi \cdot f}\right)}{\pi} \cdot -4
      \end{array}
      
      Derivation
      1. Initial program 6.7%

        \[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right) \]
      2. Taylor expanded in f around 0

        \[\leadsto \color{blue}{-4 \cdot \frac{\log \left(\frac{2}{\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)}\right) + -1 \cdot \log f}{\mathsf{PI}\left(\right)}} \]
      3. Step-by-step derivation
        1. *-commutativeN/A

          \[\leadsto \frac{\log \left(\frac{2}{\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)}\right) + -1 \cdot \log f}{\mathsf{PI}\left(\right)} \cdot \color{blue}{-4} \]
        2. lower-*.f64N/A

          \[\leadsto \frac{\log \left(\frac{2}{\frac{1}{4} \cdot \mathsf{PI}\left(\right) - \frac{-1}{4} \cdot \mathsf{PI}\left(\right)}\right) + -1 \cdot \log f}{\mathsf{PI}\left(\right)} \cdot \color{blue}{-4} \]
      4. Applied rewrites95.8%

        \[\leadsto \color{blue}{\frac{\log \left(\frac{2}{\left(\pi \cdot 0.5\right) \cdot f}\right)}{\pi} \cdot -4} \]
      5. Taylor expanded in f around 0

        \[\leadsto \frac{\log \left(\frac{4}{f \cdot \mathsf{PI}\left(\right)}\right)}{\pi} \cdot -4 \]
      6. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \frac{\log \left(\frac{4}{f \cdot \mathsf{PI}\left(\right)}\right)}{\pi} \cdot -4 \]
        2. *-commutativeN/A

          \[\leadsto \frac{\log \left(\frac{4}{\mathsf{PI}\left(\right) \cdot f}\right)}{\pi} \cdot -4 \]
        3. lower-*.f64N/A

          \[\leadsto \frac{\log \left(\frac{4}{\mathsf{PI}\left(\right) \cdot f}\right)}{\pi} \cdot -4 \]
        4. lift-PI.f6495.8

          \[\leadsto \frac{\log \left(\frac{4}{\pi \cdot f}\right)}{\pi} \cdot -4 \]
      7. Applied rewrites95.8%

        \[\leadsto \frac{\log \left(\frac{4}{\pi \cdot f}\right)}{\pi} \cdot -4 \]
      8. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2025132 
      (FPCore (f)
        :name "VandenBroeck and Keller, Equation (20)"
        :precision binary64
        (- (* (/ 1.0 (/ PI 4.0)) (log (/ (+ (exp (* (/ PI 4.0) f)) (exp (- (* (/ PI 4.0) f)))) (- (exp (* (/ PI 4.0) f)) (exp (- (* (/ PI 4.0) f)))))))))