\[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\]
\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}
double f(double x_re, double x_im, double y_re, double y_im) {
        double r8544 = x_im;
        double r8545 = y_re;
        double r8546 = r8544 * r8545;
        double r8547 = x_re;
        double r8548 = y_im;
        double r8549 = r8547 * r8548;
        double r8550 = r8546 - r8549;
        double r8551 = r8545 * r8545;
        double r8552 = r8548 * r8548;
        double r8553 = r8551 + r8552;
        double r8554 = r8550 / r8553;
        return r8554;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019310 
(FPCore (x.re x.im y.re y.im)
  :name "_divideComplex, imaginary part"
  :precision binary64
  (/ (- (* x.im y.re) (* x.re y.im)) (+ (* y.re y.re) (* y.im y.im))))

Backtrace

match: no matching clause for 'binary64LC
match:error/opt/racket-7.2/collects/racket/match/runtime.rkt240
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2463
make-multiplication-subnode/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2440
make-multiplication-node/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2340
map/opt/racket-7.2/collects/racket/private/map.rkt3513
f45/opt/racket-7.2/collects/racket/match/compiler.rkt50740
map/opt/racket-7.2/collects/racket/private/map.rkt3513
f45/opt/racket-7.2/collects/racket/match/compiler.rkt50740
simplify/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt160
approximate9/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/taylor.rkt120
(unnamed)/opt/racket-7.2/collects/racket/contract/private/arrow-higher-order.rkt36033
location-do/data/pavpan/nightlies/herbie/fix-interface-bugs/src/programs.rkt640
(unnamed)/opt/racket-7.2/collects/racket/contract/private/arrow-higher-order.rkt36033
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1516
taylor-alt/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1450
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1667
gen-series!/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1590
run-iter!/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3260
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3644
run-improve47/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3450
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.2/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.2/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128