\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}
t_0 := 0.005555555555555556 \cdot \left(angle \cdot \pi\right)\\
t_1 := \sin t_0\\
t_2 := \left(y-scale \cdot y-scale\right) \cdot \left(x-scale \cdot x-scale\right)\\
t_3 := \frac{\left(b \cdot b\right) \cdot {t_1}^{4}}{t_2}\\
t_4 := \cos t_0\\
t_5 := \left(b \cdot b\right) \cdot {t_4}^{4}\\
t_6 := 8 \cdot \frac{{t_4}^{2} \cdot \left(\left(b \cdot b\right) \cdot {t_1}^{2}\right)}{t_2}\\
\mathbf{if}\;a \leq -5.291857281523912 \cdot 10^{-67}:\\
\;\;\;\;-a \cdot \left(a \cdot \mathsf{fma}\left(4, t_3, \mathsf{fma}\left(4, \frac{\frac{t_5}{y-scale \cdot y-scale}}{x-scale \cdot x-scale}, t_6\right)\right)\right)\\
\mathbf{elif}\;a \leq 2.7136344850281534 \cdot 10^{+56}:\\
\;\;\;\;0\\
\mathbf{else}:\\
\;\;\;\;-a \cdot \left(a \cdot \mathsf{fma}\left(4, t_3, \mathsf{fma}\left(4, \frac{t_5}{{\left(y-scale \cdot x-scale\right)}^{2}}, t_6\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
(let* ((t_0 (* 0.005555555555555556 (* angle PI)))
(t_1 (sin t_0))
(t_2 (* (* y-scale y-scale) (* x-scale x-scale)))
(t_3 (/ (* (* b b) (pow t_1 4.0)) t_2))
(t_4 (cos t_0))
(t_5 (* (* b b) (pow t_4 4.0)))
(t_6 (* 8.0 (/ (* (pow t_4 2.0) (* (* b b) (pow t_1 2.0))) t_2))))
(if (<= a -5.291857281523912e-67)
(-
(*
a
(*
a
(fma
4.0
t_3
(fma 4.0 (/ (/ t_5 (* y-scale y-scale)) (* x-scale x-scale)) t_6)))))
(if (<= a 2.7136344850281534e+56)
0.0
(-
(*
a
(*
a
(fma
4.0
t_3
(fma 4.0 (/ t_5 (pow (* y-scale x-scale) 2.0)) t_6)))))))))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 t_0 = 0.005555555555555556 * (angle * ((double) M_PI));
double t_1 = sin(t_0);
double t_2 = (y_45_scale * y_45_scale) * (x_45_scale * x_45_scale);
double t_3 = ((b * b) * pow(t_1, 4.0)) / t_2;
double t_4 = cos(t_0);
double t_5 = (b * b) * pow(t_4, 4.0);
double t_6 = 8.0 * ((pow(t_4, 2.0) * ((b * b) * pow(t_1, 2.0))) / t_2);
double tmp;
if (a <= -5.291857281523912e-67) {
tmp = -(a * (a * fma(4.0, t_3, fma(4.0, ((t_5 / (y_45_scale * y_45_scale)) / (x_45_scale * x_45_scale)), t_6))));
} else if (a <= 2.7136344850281534e+56) {
tmp = 0.0;
} else {
tmp = -(a * (a * fma(4.0, t_3, fma(4.0, (t_5 / pow((y_45_scale * x_45_scale), 2.0)), t_6))));
}
return tmp;
}



Bits error versus a



Bits error versus b



Bits error versus angle



Bits error versus x-scale



Bits error versus y-scale
if a < -5.291857281523912e-67Initial program 49.3
Taylor expanded in a around 0 43.9
Simplified43.9
Applied associate-*l*_binary6436.8
Applied associate-/r*_binary6437.0
if -5.291857281523912e-67 < a < 2.7136344850281534e56Initial program 34.7
Taylor expanded in b around 0 32.7
Simplified24.5
if 2.7136344850281534e56 < a Initial program 57.1
Taylor expanded in a around 0 51.0
Simplified51.0
Applied associate-*l*_binary6440.0
Applied pow2_binary6440.0
Applied pow2_binary6440.0
Applied pow-prod-down_binary6439.0
Simplified39.0
Final simplification29.6
herbie shell --seed 2021280
(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))))