\frac{r \cdot \sin b}{\cos \left(a + b\right)}\frac{r \cdot \sin b}{\cos a \cdot \cos b - \sin a \cdot \sin b}double f(double r, double a, double b) {
double r1030387 = r;
double r1030388 = b;
double r1030389 = sin(r1030388);
double r1030390 = r1030387 * r1030389;
double r1030391 = a;
double r1030392 = r1030391 + r1030388;
double r1030393 = cos(r1030392);
double r1030394 = r1030390 / r1030393;
return r1030394;
}
double f(double r, double a, double b) {
double r1030395 = r;
double r1030396 = b;
double r1030397 = sin(r1030396);
double r1030398 = r1030395 * r1030397;
double r1030399 = a;
double r1030400 = cos(r1030399);
double r1030401 = cos(r1030396);
double r1030402 = r1030400 * r1030401;
double r1030403 = sin(r1030399);
double r1030404 = r1030403 * r1030397;
double r1030405 = r1030402 - r1030404;
double r1030406 = r1030398 / r1030405;
return r1030406;
}



Bits error versus r



Bits error versus a



Bits error versus b
Results
Initial program 15.5
rmApplied cos-sum0.3
rmApplied *-un-lft-identity0.3
Applied times-frac0.3
Simplified0.3
Taylor expanded around inf 0.3
Final simplification0.3
herbie shell --seed 2019165 +o rules:numerics
(FPCore (r a b)
:name "r*sin(b)/cos(a+b), A"
(/ (* r (sin b)) (cos (+ a b))))