\[\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R\]

\cos^{-1} \left(\sin \phi_1 \cdot \sin \phi_2 + \left(\cos \phi_1 \cdot \cos \phi_2\right) \cdot \cos \left(\lambda_1 - \lambda_2\right)\right) \cdot R

double f(double R, double lambda1, double lambda2, double phi1, double phi2) {
        double r15749 = phi1;
        double r15750 = sin(r15749);
        double r15751 = phi2;
        double r15752 = sin(r15751);
        double r15753 = r15750 * r15752;
        double r15754 = cos(r15749);
        double r15755 = cos(r15751);
        double r15756 = r15754 * r15755;
        double r15757 = lambda1;
        double r15758 = lambda2;
        double r15759 = r15757 - r15758;
        double r15760 = cos(r15759);
        double r15761 = r15756 * r15760;
        double r15762 = r15753 + r15761;
        double r15763 = acos(r15762);
        double r15764 = R;
        double r15765 = r15763 * r15764;
        return r15765;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019195 
(FPCore (R lambda1 lambda2 phi1 phi2)
  :name "Spherical law of cosines"
  (* (acos (+ (* (sin phi1) (sin phi2)) (* (* (cos phi1) (cos phi2)) (cos (- lambda1 lambda2))))) R))

Backtrace

get-representation: Unknown representation #f		L	C
(unnamed)	/data/pavpan/nightlies/herbie/various-cleanup/src/core/localize.rkt	23	13
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
map	/opt/racket-7.0/collects/racket/private/map.rkt	35	13
parse-loop30	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
localize-error	/data/pavpan/nightlies/herbie/various-cleanup/src/core/localize.rkt	61	0
localize!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	123	0
run-iter!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	323	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	359	4
run-improve47	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	342	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28