> By the way, a particular application failed to
> run because a J6 empty vector turned out not to
> be 'identical' to the corresponding J5 empty
> vector and it was difficult to see, via their
> linear representation, that they were actually
> different in some sense.
There had been no changes in 5!:5 on empty vectors
or boxed empty vectors between J6 and J5.
----- Original Message -----
From: Jose Mario Quintana <[EMAIL PROTECTED]>
Date: Tuesday, August 15, 2006 2:17 pm
Subject: RE: [Jbeta] Linear Representation
> > Behalf Of Mark D. Niemiec
> > Jose Mario Quintana <[EMAIL PROTECTED]> wrote:
> > > "5!:5 y Linear. The linear representation is a string which, when
> > > interpreted, produces the named object."
> > >
> [...]
> >
> > One of the idiosyncracies of empty arrays is that they are
> > considered equal, even if they have different data types.
> > This is rarely important, but the underlying data type can
> > reveal itself when fill elements are being used (as with {. or {:)
> > and certainly with 3!:0
> >
> [...]
> > A problem with 5!:5 and 5!:6 is that they produce
> representations that are
> > equal to the original, but not necessarily IDENTICAL in all
> > aspects. For example, they do not preserve type:
> >
> > type f0=:-~1.5 NB. real clone of 0
> > 8
> > f0
> > 0
> > type "[EMAIL PROTECTED]'f0' NB. This forgets the 'realness' of the zero
> > 1
> > f0+!20x NB. real 0 trumps extended precision
> > 2.4329e18
> > ("[EMAIL PROTECTED]'f0')+!20x NB. freeze-dried and reconstituted 0 does
> > not
> > 2432902008176640000
> >
> > (and, in the cited example, lr does not preserve the type of the
> empty> list either).
>
>
> > Behalf Of Roger Hui
> > It comes down to whether there is one empty vector
> > or more than one empty vector. (*)
> [...]
> >
> > I will probably change 5!:5 to preserve the
>
> That seems to make more sense than the alternative of clarifying
> that "when
> interpreted, produces the named object" but it might not always be
> 'identically' the same object.
>
> By the way, a particular application failed to run because a J6
> empty vector
> turned out not to be 'identical' to the corresponding J5 empty
> vector and it
> was difficult to see, via their linear representation, that they were
> actually different in some sense.
>
> > distinction between <i.0 and <'' without answering
> > (*) one way or the other.
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