\[\tan^{-1}_* \frac{\sin \left(\lambda_1 - \lambda_2\right) \cdot \cos \phi_2}{\cos \phi_1 \cdot \sin \phi_2 - \left(\sin \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)}\]
\tan^{-1}_* \frac{\sin \left(\lambda_1 - \lambda_2\right) \cdot \cos \phi_2}{\cos \phi_1 \cdot \sin \phi_2 - \left(\sin \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)}
double code(double lambda1, double lambda2, double phi1, double phi2) {
	return ((double) atan2(((double) (((double) sin(((double) (lambda1 - lambda2)))) * ((double) cos(phi2)))), ((double) (((double) (((double) cos(phi1)) * ((double) sin(phi2)))) - ((double) (((double) (((double) sin(phi1)) * ((double) cos(phi2)))) * ((double) cos(((double) (lambda1 - lambda2))))))))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020165 
(FPCore (lambda1 lambda2 phi1 phi2)
  :name "Bearing on a great circle"
  :precision binary64
  (atan2 (* (sin (- lambda1 lambda2)) (cos phi2)) (- (* (cos phi1) (sin phi2)) (* (* (sin phi1) (cos phi2)) (cos (- lambda1 lambda2))))))

Backtrace

ival-hi: contract violation expected: ival? given: #<procedure:interval>LC
for-loop/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt3711
hyperrect-weight/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt360
total-weight/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1132
log-space-improvement/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1100
(unnamed)/opt/racket-7.5/collects/racket/contract/private/arrow-higher-order.rkt37533
get-hyperrects/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1230
make-sampler/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt1470
prepare-points-intervals/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt900
run-improve47/data/pavpan/nightlies/herbie/ival-find-range/src/mainloop.rkt3650
.../more-scheme.rkt:261:28unknown
run/opt/racket-7.5/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.5/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.5/collects/racket/private/more-scheme.rkt26128

Reproduce

herbie shell --seed 2020165 
(FPCore (lambda1 lambda2 phi1 phi2)
  :name "Bearing on a great circle"
  :precision binary64
  (atan2 (* (sin (- lambda1 lambda2)) (cos phi2)) (- (* (cos phi1) (sin phi2)) (* (* (sin phi1) (cos phi2)) (cos (- lambda1 lambda2))))))