\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\cos delta - \sin \phi_1 \cdot \sin \left(\sin^{-1} \left(\sin \phi_1 \cdot \cos delta + \left(\cos \phi_1 \cdot \sin delta\right) \cdot \cos theta\right)\right)}\lambda_1 + \tan^{-1}_* \frac{\left(\sin theta \cdot \sin delta\right) \cdot \cos \phi_1}{\log \left(e^{\cos delta - \sin \phi_1 \cdot \sin \left(\mathsf{log1p}\left(\mathsf{expm1}\left(\sin^{-1} \left(\sin delta \cdot \left(\cos \phi_1 \cdot \cos theta\right) + \sin \phi_1 \cdot \cos delta\right)\right)\right)\right)}\right)}double f(double lambda1, double phi1, double __attribute__((unused)) phi2, double delta, double theta) {
double r105155 = lambda1;
double r105156 = theta;
double r105157 = sin(r105156);
double r105158 = delta;
double r105159 = sin(r105158);
double r105160 = r105157 * r105159;
double r105161 = phi1;
double r105162 = cos(r105161);
double r105163 = r105160 * r105162;
double r105164 = cos(r105158);
double r105165 = sin(r105161);
double r105166 = r105165 * r105164;
double r105167 = r105162 * r105159;
double r105168 = cos(r105156);
double r105169 = r105167 * r105168;
double r105170 = r105166 + r105169;
double r105171 = asin(r105170);
double r105172 = sin(r105171);
double r105173 = r105165 * r105172;
double r105174 = r105164 - r105173;
double r105175 = atan2(r105163, r105174);
double r105176 = r105155 + r105175;
return r105176;
}
double f(double lambda1, double phi1, double __attribute__((unused)) phi2, double delta, double theta) {
double r105177 = lambda1;
double r105178 = theta;
double r105179 = sin(r105178);
double r105180 = delta;
double r105181 = sin(r105180);
double r105182 = r105179 * r105181;
double r105183 = phi1;
double r105184 = cos(r105183);
double r105185 = r105182 * r105184;
double r105186 = cos(r105180);
double r105187 = sin(r105183);
double r105188 = cos(r105178);
double r105189 = r105184 * r105188;
double r105190 = r105181 * r105189;
double r105191 = r105187 * r105186;
double r105192 = r105190 + r105191;
double r105193 = asin(r105192);
double r105194 = expm1(r105193);
double r105195 = log1p(r105194);
double r105196 = sin(r105195);
double r105197 = r105187 * r105196;
double r105198 = r105186 - r105197;
double r105199 = exp(r105198);
double r105200 = log(r105199);
double r105201 = atan2(r105185, r105200);
double r105202 = r105177 + r105201;
return r105202;
}



Bits error versus lambda1



Bits error versus phi1



Bits error versus phi2



Bits error versus delta



Bits error versus theta
Results
Initial program 0.2
rmApplied add-cbrt-cube0.2
Simplified0.2
rmApplied log1p-expm1-u0.2
Simplified0.2
rmApplied add-log-exp0.2
Applied add-log-exp0.2
Applied diff-log0.2
Simplified0.2
Final simplification0.2
herbie shell --seed 2020064 +o rules:numerics
(FPCore (lambda1 phi1 phi2 delta theta)
:name "Destination given bearing on a great circle"
:precision binary64
(+ lambda1 (atan2 (* (* (sin theta) (sin delta)) (cos phi1)) (- (cos delta) (* (sin phi1) (sin (asin (+ (* (sin phi1) (cos delta)) (* (* (cos phi1) (sin delta)) (cos theta))))))))))