It's a feature, an inevitable consequence of numeric
conversion and rank.  If it breaks your code you have
to rewrite your code.



----- Original Message -----
From: Ian Clark <[email protected]>
Date: Monday, April 5, 2010 16:12
Subject: Re: [Jprogramming] lines in display
To: Programming forum <[email protected]>

> On not quite the same problem but a related one:
> 
> If z is an integer table, under what conditions would you expect 
> ": z
> to have the same number of rows as z? Under more restricted
> conditions, when is (z -: ". ": z) ?
> 
> Clearly you can't expect rank to be preserved if z=: i.1 3 --since
> under ": the information gets lost to enable you to distinguish it
> from i.3. But what about z=: i.3 1 ?
> 
> Consider the following:
> 
>    (". ": i.z) ; i.z=: 3 2
> +---+---+
> |0 1|0 1|
> |2 3|2 3|
> |4 5|4 5|
> +---+---+
>    (". ": i.z) ; i.z=: 3 1
> +-----+-+
> |0 1 2|0|
> |     |1|
> |     |2|
> +-----+-+
> 
> Is this a bug or a feature? (It's breaking my code, for which I have
> so far only found an inelegant fix).
> 
> Ian
> 
> 
> On Fri, Apr 2, 2010 at 10:20 PM, Roger Hui <[email protected]> wrote:
> > If x is a rank 2 or higher numeric array, how many
> > lines are in the display of x?  For example,
> > there are 14 lines in the display of  i. 3 4 5 .
> >
> > I've worked on a related problem on-and-off for years,
> > starting in 1991, and only came to a good answer
> > for this problem just a few days ago.
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