Exception for Octave 3.8, jcobi/1

\[\alpha > -1 \land \beta > -1\]

Math

\[\]

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2021043 
(FPCore (alpha beta)
  :name "Octave 3.8, jcobi/1"
  :precision binary64
  :pre (and (> alpha -1.0) (> beta -1.0))
  (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))

Backtrace

cdr: contract violation expected: pair? given: 'i		L	C
for-loop	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/programs.rkt	220	4
(unnamed)	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/programs.rkt	216	2
(unnamed)	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/programs.rkt	150	2
(unnamed)	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/points.rkt	169	4
errors	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/points.rkt	166	0
make-alt-table	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/core/alt-table.rkt	33	0
(unnamed)	/opt/racket-7.9/collects/racket/contract/private/arrow-val-first.rkt	486	18
setup-prog!	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/mainloop.rkt	80	0
for-loop	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/mainloop.rkt	453	4
run-improve	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/mainloop.rkt	447	0
(unnamed)	/data/pavpan/nightlies/herbie/mpmf-cost-multi-input/src/sandbox.rkt	54	6
run	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.9/collects/racket/engine.rkt	42	24

Reproduce

herbie shell --seed 2021043 
(FPCore (alpha beta)
  :name "Octave 3.8, jcobi/1"
  :precision binary64
  :pre (and (> alpha -1.0) (> beta -1.0))
  (/ (+ (/ (- beta alpha) (+ (+ alpha beta) 2.0)) 1.0) 2.0))