Re: [Bug-apl] Question about behavior of ⍋

[Elias Mårtenson]

Dyadic grade doesn't make much sense in the context of Unicode though. How do you grade an arbitrary Unicode string?

That issue is there even if we completely disregard all the other Unicode-related collating issues.

Regards,

Elias

On 8 July 2014 12:00, David B. Lamkins <address@hidden> wrote:

Check my follow-up post.

I'm fairly certain that the issue is whether monadic grade applied to a
list of strings should do anything but signal a domain error. The ISO
spec says that monadic grade is defined only on numeric arguments.

My test case appears to have monadic grade treating strings as if they
encode numbers in a sufficiently large base.

If you want to sort strings, use dyadic grade. The left argument
specifies a collating sequence.

On Tue, 2014-07-08 at 11:43 +0800, Elias Mårtenson wrote:
> Ordering by size first makes very little sense to me. It makes it very
> hard to sort any list of strings.
>
>
> I was hoping that the following would have done so, but it also
> suffers from the "length first" issue:
>
>
>       z[⍋ ⎕UCS¨ z←'aa' 'xx' 'aaa' 'xxx']
>  aa xx aaa xxx
>
>
> What is the proper way to sort strings given the existing semantics of
> grade?
>
>
> Regards,
> Elias
>
>
> On 8 July 2014 02:34, David Lamkins <address@hidden> wrote:
>         Looking at the spec, it seems that monadic grade is defined
>         only for numeric data.
>
>
>         That leaves open the question of whether my example should
>         have signaled a domain error.
>
>
>
>         On Mon, Jul 7, 2014 at 11:25 AM, David Lamkins
>         <address@hidden> wrote:
>                 Given a list of character vectors (and scalars), grade
>                 appears to generate the permutation vector first by
>                 length then by content.
>
>                       ⍋'aaa' 'xx' 'y' 'bbb' 'cc'
>                 3 5 2 1 4
>
>
>                 This seems counterintuitive. It seems as if ⍋ treats
>                 character strings like numbers. Is this a bug?
>
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>         --
>         "The secret to creativity is knowing how to hide your
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>
>
>         http://soundcloud.com/davidlamkins
>         http://reverbnation.com/lamkins
>         http://reverbnation.com/lcw
>         http://lamkins-guitar.com/
>         http://lamkins.net/
>         http://successful-lisp.com/
>
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