\left(0.5 \cdot \cos re\right) \cdot \left(e^{-im} + e^{im}\right)\left(0.5 \cdot \cos re\right) \cdot \left(\frac{1}{12} \cdot {im}^{4} + \left({im}^{2} + 2\right)\right)double f(double re, double im) {
double r32990 = 0.5;
double r32991 = re;
double r32992 = cos(r32991);
double r32993 = r32990 * r32992;
double r32994 = im;
double r32995 = -r32994;
double r32996 = exp(r32995);
double r32997 = exp(r32994);
double r32998 = r32996 + r32997;
double r32999 = r32993 * r32998;
return r32999;
}
double f(double re, double im) {
double r33000 = 0.5;
double r33001 = re;
double r33002 = cos(r33001);
double r33003 = r33000 * r33002;
double r33004 = 0.08333333333333333;
double r33005 = im;
double r33006 = 4.0;
double r33007 = pow(r33005, r33006);
double r33008 = r33004 * r33007;
double r33009 = 2.0;
double r33010 = pow(r33005, r33009);
double r33011 = r33010 + r33009;
double r33012 = r33008 + r33011;
double r33013 = r33003 * r33012;
return r33013;
}



Bits error versus re



Bits error versus im
Results
Initial program 0.0
Taylor expanded around 0 0.7
Final simplification0.7
herbie shell --seed 2019304
(FPCore (re im)
:name "math.cos on complex, real part"
:precision binary64
(* (* 0.5 (cos re)) (+ (exp (- im)) (exp im))))