Comparisons involving extended precision numbers are defined to be exact.


On Wed, Feb 19, 2014 at 5:35 PM, Pascal Jasmin <godspiral2...@yahoo.ca>wrote:

>
>
> it gets surprising/ineffective/unnapplicable if extended numbers are used:
>
>   T=:  2^_34x
>
>   2 = 2+T%2
> 0
>    2 =!.T 2+ 2^_44166x
> 0
>
> Though to fix your issue:
>
>    2 =!.T 2+ 2^_35
> 1
>    2 =!.T 2+ 2^_33
> 1
>    2 =!.T 2+ 2^_32
>
> 0
>
>
>
> ----- Original Message -----
> From: Ian Clark <earthspo...@gmail.com>
> To: Programming forum <programm...@jsoftware.com>
> Cc:
> Sent: Wednesday, February 19, 2014 8:24:09 PM
> Subject: Re: [Jprogramming] Getting Fit (!.) to work
>
> 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?
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> >>
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