\frac{\frac{\left(\left(2 \cdot \left({b}^{2} - {a}^{2}\right)\right) \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right) \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)}{x-scale}}{y-scale} \cdot \frac{\frac{\left(\left(2 \cdot \left({b}^{2} - {a}^{2}\right)\right) \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right) \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)}{x-scale}}{y-scale} - \left(4 \cdot \frac{\frac{{\left(a \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2} + {\left(b \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2}}{x-scale}}{x-scale}\right) \cdot \frac{\frac{{\left(a \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2} + {\left(b \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2}}{y-scale}}{y-scale}\begin{array}{l}
\mathbf{if}\;y-scale \leq -3.390130520580369 \cdot 10^{-159}:\\
\;\;\;\;-4 \cdot \frac{\left(b \cdot b\right) \cdot \left(a \cdot a\right)}{x-scale \cdot \left(x-scale \cdot \left(y-scale \cdot y-scale\right)\right)}\\
\mathbf{elif}\;y-scale \leq 2.2977844005398353 \cdot 10^{-161}:\\
\;\;\;\;\frac{\frac{\frac{\frac{4 \cdot \left(\left(\left(b \cdot b - a \cdot a\right) \cdot \left(\sin \left(\frac{angle}{180} \cdot \pi\right) \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)\right) \cdot \left(\left(b \cdot b - a \cdot a\right) \cdot \left(\sin \left(\frac{angle}{180} \cdot \pi\right) \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)\right)\right)}{x-scale}}{x-scale}}{y-scale} + \frac{{\left(a \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2} + {\left(b \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2}}{y-scale} \cdot \left(-4 \cdot \frac{\frac{{\left(a \cdot \sin \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2} + {\left(b \cdot \cos \left(\frac{angle}{180} \cdot \pi\right)\right)}^{2}}{x-scale}}{x-scale}\right)}{y-scale}\\
\mathbf{else}:\\
\;\;\;\;\left(-\frac{a \cdot a}{x-scale \cdot \left(x-scale \cdot \left(y-scale \cdot y-scale\right)\right)}\right) \cdot \left(\left(b \cdot b\right) \cdot \left(8 \cdot \left({\sin \left(0.005555555555555556 \cdot \left(angle \cdot \pi\right)\right)}^{2} \cdot {\cos \left(0.005555555555555556 \cdot \left(angle \cdot \pi\right)\right)}^{2}\right) + 4 \cdot \left({\sin \left(0.005555555555555556 \cdot \left(angle \cdot \pi\right)\right)}^{4} + {\log \left(e^{\cos \left(0.005555555555555556 \cdot \left(angle \cdot \pi\right)\right)}\right)}^{4}\right)\right)\right)\\
\end{array}(FPCore (a b angle x-scale y-scale)
:precision binary64
(-
(*
(/
(/
(*
(* (* 2.0 (- (pow b 2.0) (pow a 2.0))) (sin (* (/ angle 180.0) PI)))
(cos (* (/ angle 180.0) PI)))
x-scale)
y-scale)
(/
(/
(*
(* (* 2.0 (- (pow b 2.0) (pow a 2.0))) (sin (* (/ angle 180.0) PI)))
(cos (* (/ angle 180.0) PI)))
x-scale)
y-scale))
(*
(*
4.0
(/
(/
(+
(pow (* a (sin (* (/ angle 180.0) PI))) 2.0)
(pow (* b (cos (* (/ angle 180.0) PI))) 2.0))
x-scale)
x-scale))
(/
(/
(+
(pow (* a (cos (* (/ angle 180.0) PI))) 2.0)
(pow (* b (sin (* (/ angle 180.0) PI))) 2.0))
y-scale)
y-scale))))(FPCore (a b angle x-scale y-scale)
:precision binary64
(if (<= y-scale -3.390130520580369e-159)
(* -4.0 (/ (* (* b b) (* a a)) (* x-scale (* x-scale (* y-scale y-scale)))))
(if (<= y-scale 2.2977844005398353e-161)
(/
(+
(/
(/
(/
(*
4.0
(*
(*
(- (* b b) (* a a))
(* (sin (* (/ angle 180.0) PI)) (cos (* (/ angle 180.0) PI))))
(*
(- (* b b) (* a a))
(* (sin (* (/ angle 180.0) PI)) (cos (* (/ angle 180.0) PI))))))
x-scale)
x-scale)
y-scale)
(*
(/
(+
(pow (* a (cos (* (/ angle 180.0) PI))) 2.0)
(pow (* b (sin (* (/ angle 180.0) PI))) 2.0))
y-scale)
(*
-4.0
(/
(/
(+
(pow (* a (sin (* (/ angle 180.0) PI))) 2.0)
(pow (* b (cos (* (/ angle 180.0) PI))) 2.0))
x-scale)
x-scale))))
y-scale)
(*
(- (/ (* a a) (* x-scale (* x-scale (* y-scale y-scale)))))
(*
(* b b)
(+
(*
8.0
(*
(pow (sin (* 0.005555555555555556 (* angle PI))) 2.0)
(pow (cos (* 0.005555555555555556 (* angle PI))) 2.0)))
(*
4.0
(+
(pow (sin (* 0.005555555555555556 (* angle PI))) 4.0)
(pow
(log (exp (cos (* 0.005555555555555556 (* angle PI)))))
4.0)))))))))double code(double a, double b, double angle, double x_45_scale, double y_45_scale) {
return ((((((2.0 * (pow(b, 2.0) - pow(a, 2.0))) * sin((angle / 180.0) * ((double) M_PI))) * cos((angle / 180.0) * ((double) M_PI))) / x_45_scale) / y_45_scale) * (((((2.0 * (pow(b, 2.0) - pow(a, 2.0))) * sin((angle / 180.0) * ((double) M_PI))) * cos((angle / 180.0) * ((double) M_PI))) / x_45_scale) / y_45_scale)) - ((4.0 * (((pow((a * sin((angle / 180.0) * ((double) M_PI))), 2.0) + pow((b * cos((angle / 180.0) * ((double) M_PI))), 2.0)) / x_45_scale) / x_45_scale)) * (((pow((a * cos((angle / 180.0) * ((double) M_PI))), 2.0) + pow((b * sin((angle / 180.0) * ((double) M_PI))), 2.0)) / y_45_scale) / y_45_scale));
}
double code(double a, double b, double angle, double x_45_scale, double y_45_scale) {
double tmp;
if (y_45_scale <= -3.390130520580369e-159) {
tmp = -4.0 * (((b * b) * (a * a)) / (x_45_scale * (x_45_scale * (y_45_scale * y_45_scale))));
} else if (y_45_scale <= 2.2977844005398353e-161) {
tmp = (((((4.0 * ((((b * b) - (a * a)) * (sin((angle / 180.0) * ((double) M_PI)) * cos((angle / 180.0) * ((double) M_PI)))) * (((b * b) - (a * a)) * (sin((angle / 180.0) * ((double) M_PI)) * cos((angle / 180.0) * ((double) M_PI)))))) / x_45_scale) / x_45_scale) / y_45_scale) + (((pow((a * cos((angle / 180.0) * ((double) M_PI))), 2.0) + pow((b * sin((angle / 180.0) * ((double) M_PI))), 2.0)) / y_45_scale) * (-4.0 * (((pow((a * sin((angle / 180.0) * ((double) M_PI))), 2.0) + pow((b * cos((angle / 180.0) * ((double) M_PI))), 2.0)) / x_45_scale) / x_45_scale)))) / y_45_scale;
} else {
tmp = -((a * a) / (x_45_scale * (x_45_scale * (y_45_scale * y_45_scale)))) * ((b * b) * ((8.0 * (pow(sin(0.005555555555555556 * (angle * ((double) M_PI))), 2.0) * pow(cos(0.005555555555555556 * (angle * ((double) M_PI))), 2.0))) + (4.0 * (pow(sin(0.005555555555555556 * (angle * ((double) M_PI))), 4.0) + pow(log(exp(cos(0.005555555555555556 * (angle * ((double) M_PI))))), 4.0)))));
}
return tmp;
}



Bits error versus a



Bits error versus b



Bits error versus angle



Bits error versus x-scale



Bits error versus y-scale
Results
if y-scale < -3.3901305205803688e-159Initial program 39.7
Taylor expanded around 0 35.3
Simplified32.4
if -3.3901305205803688e-159 < y-scale < 2.2977844005398353e-161Initial program 51.7
rmApplied associate-*r/_binary64_2048.0
Applied associate-*l/_binary64_2147.1
Applied sub-div_binary64_8547.1
Simplified46.0
if 2.2977844005398353e-161 < y-scale Initial program 39.0
Taylor expanded around inf 35.8
Simplified31.8
rmApplied add-log-exp_binary64_11731.8
Final simplification34.2
herbie shell --seed 2020343
(FPCore (a b angle x-scale y-scale)
:name "Simplification of discriminant from scale-rotated-ellipse"
:precision binary64
(- (* (/ (/ (* (* (* 2.0 (- (pow b 2.0) (pow a 2.0))) (sin (* (/ angle 180.0) PI))) (cos (* (/ angle 180.0) PI))) x-scale) y-scale) (/ (/ (* (* (* 2.0 (- (pow b 2.0) (pow a 2.0))) (sin (* (/ angle 180.0) PI))) (cos (* (/ angle 180.0) PI))) x-scale) y-scale)) (* (* 4.0 (/ (/ (+ (pow (* a (sin (* (/ angle 180.0) PI))) 2.0) (pow (* b (cos (* (/ angle 180.0) PI))) 2.0)) x-scale) x-scale)) (/ (/ (+ (pow (* a (cos (* (/ angle 180.0) PI))) 2.0) (pow (* b (sin (* (/ angle 180.0) PI))) 2.0)) y-scale) y-scale))))