You have to consider the definition of tolerant equality carefully. It is the _relative_ difference that matters, not the absolute difference. The absolute difference between 2 and 2+T+T is 2*T, but the relative difference is (2*T)%2+T+T, and this relative difference is less than T.
On Wed, Feb 19, 2014 at 5:24 PM, Ian Clark <earthspo...@gmail.com> wrote: > Okay, I was reading that as *less* than 2^_34 > > All is not as it seems however... > > ] T=: 2^_34 > 5.82077e_11 > 2 =!.T 2+T > 1 > 2 =!.T 2+T+T NB. I'd expect 0 here > 1 > 2 =!.T 2+T+T+T > 0 > NB. at last! > > > > On Thu, Feb 20, 2014 at 12:37 AM, Henry Rich <henryhr...@nc.rr.com> wrote: > > > Comparison tolerance cannot be more than 2^_34. > > > > (So that integer comparisons on 32-bit machines do not have to worry > about > > tolerance) > > > > Henry Rich > > > > > > > > On 2/19/2014 7:03 PM, Ian Clark wrote: > > > >> I'm trying to construct an example using Fit (!.) to customize a given > >> primitive (e.g. =) to set its tolerance. > >> Try as I might I cannot get variants of this to work: > >> > >> T=: 0.001 > >> 2 =!.T 2.0001 > >> |domain error > >> | 2 =!.T 2.0001 > >> > >> What am I doing wrong? > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > >> > >> ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
