Exception for Migdal et al, Equation (51)

Math

\[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}\]

C

double code(double k, double n) {
	return ((double) (((double) (1.0 / ((double) sqrt(k)))) * ((double) pow(((double) (((double) (2.0 * ((double) M_PI))) * n)), ((double) (((double) (1.0 - k)) / 2.0))))));
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020165 
(FPCore (k n)
  :name "Migdal et al, Equation (51)"
  :precision binary64
  (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))

Backtrace

ival-hi: contract violation expected: ival? given: #<procedure:interval>		L	C
for-loop	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	37	11
hyperrect-weight	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	36	0
total-weight	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	113	2
log-space-improvement	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	110	0
(unnamed)	/opt/racket-7.5/collects/racket/contract/private/arrow-higher-order.rkt	375	33
get-hyperrects	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	123	0
make-sampler	/data/pavpan/nightlies/herbie/ival-find-range/src/sampling.rkt	147	0
prepare-points-intervals	/data/pavpan/nightlies/herbie/ival-find-range/src/points.rkt	90	0
run-improve47	/data/pavpan/nightlies/herbie/ival-find-range/src/mainloop.rkt	365	0
.../more-scheme.rkt:261:28	unknown
run	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.5/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.5/collects/racket/private/more-scheme.rkt	261	28

Reproduce

herbie shell --seed 2020165 
(FPCore (k n)
  :name "Migdal et al, Equation (51)"
  :precision binary64
  (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))