\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\pi \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\begin{array}{l}
t_1 := \pi \cdot \sqrt{2}\\
\frac{\frac{1}{t_1}}{t} + \frac{v \cdot v}{t_1 \cdot t} \cdot -2.5
\end{array}
(FPCore (v t) :precision binary64 (/ (- 1.0 (* 5.0 (* v v))) (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
(FPCore (v t) :precision binary64 (let* ((t_1 (* PI (sqrt 2.0)))) (+ (/ (/ 1.0 t_1) t) (* (/ (* v v) (* t_1 t)) -2.5))))
double code(double v, double t) {
return (1.0 - (5.0 * (v * v))) / (((((double) M_PI) * t) * sqrt(2.0 * (1.0 - (3.0 * (v * v))))) * (1.0 - (v * v)));
}
double code(double v, double t) {
double t_1 = ((double) M_PI) * sqrt(2.0);
return ((1.0 / t_1) / t) + (((v * v) / (t_1 * t)) * -2.5);
}



Bits error versus v



Bits error versus t
Results
Initial program 0.5
Taylor expanded in v around 0 0.8
Simplified0.8
Applied add-cube-cbrt_binary640.8
Applied times-frac_binary640.7
Simplified0.7
Simplified0.7
Applied associate-*l/_binary640.5
Simplified0.5
Final simplification0.5
herbie shell --seed 2021215
(FPCore (v t)
:name "Falkner and Boettcher, Equation (20:1,3)"
:precision binary64
(/ (- 1.0 (* 5.0 (* v v))) (* (* (* PI t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))