Same but more readable for me: hcinv2 (2 #. ])`((2 #. }.) - 2 ^ [: <: #)@.{."1
hcinv2 hc i:5 _5 _4 _3 _2 _1 0 1 2 3 4 5 On 12/10/2011 12:01 AM, Kip Murray wrote: > Now we need an inverse for Raul's improved #: ("hash colon") > > hc NB. Raul's improved #: > {.@#:@(,: (2 * |)) > > hc i: 2 > 1 1 0 > 1 1 1 > 0 0 0 > 0 0 1 > 0 1 0 > > hcinv NB. improvement sought > 2&#.`(2&#.@}. - 2 ^<:@#)@.{."1 > > hcinv hc i: 2 > _2 _1 0 1 2 > > On 12/8/2011 2:41 PM, Raul Miller wrote: > ... > But this would work just as well, as a model: > > {.@#:@(,: 2 * |)i:2 > 1 1 0 > 1 1 1 > 0 0 0 > 0 0 1 > 0 1 0 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm