\left(\left(x - 1\right) \cdot \log y + \left(z - 1\right) \cdot \log \left(1 - y\right)\right) - t
\left(\left(\left(x - 1\right) \cdot \left(2 \cdot \log \left(\sqrt[3]{y}\right)\right) + \left(x - 1\right) \cdot \log \left({y}^{0.3333333333333333}\right)\right) + \left(y + \left(y \cdot y\right) \cdot \left(y \cdot 0.3333333333333333 + 0.5\right)\right) \cdot \left(1 - z\right)\right) - t(FPCore (x y z t) :precision binary64 (- (+ (* (- x 1.0) (log y)) (* (- z 1.0) (log (- 1.0 y)))) t))
(FPCore (x y z t)
:precision binary64
(-
(+
(+
(* (- x 1.0) (* 2.0 (log (cbrt y))))
(* (- x 1.0) (log (pow y 0.3333333333333333))))
(* (+ y (* (* y y) (+ (* y 0.3333333333333333) 0.5))) (- 1.0 z)))
t))double code(double x, double y, double z, double t) {
return (((x - 1.0) * log(y)) + ((z - 1.0) * log(1.0 - y))) - t;
}
double code(double x, double y, double z, double t) {
return ((((x - 1.0) * (2.0 * log(cbrt(y)))) + ((x - 1.0) * log(pow(y, 0.3333333333333333)))) + ((y + ((y * y) * ((y * 0.3333333333333333) + 0.5))) * (1.0 - z))) - t;
}



Bits error versus x



Bits error versus y



Bits error versus z



Bits error versus t
Results
Initial program 7.2
Taylor expanded around 0 0.3
Simplified0.3
rmApplied add-cube-cbrt_binary640.3
Applied log-prod_binary640.4
Applied distribute-lft-in_binary640.4
Simplified0.4
rmApplied pow1/3_binary640.4
Final simplification0.4
herbie shell --seed 2020220
(FPCore (x y z t)
:name "Statistics.Distribution.Beta:$cdensity from math-functions-0.1.5.2"
:precision binary64
(- (+ (* (- x 1.0) (log y)) (* (- z 1.0) (log (- 1.0 y)))) t))