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Re: Why (IMO) you should vote Yes to Motion 14.02



Well, we already agreed on not inferring too much from the text and we are working on a more solid foundation of the things that this Motion refers to. But

Zitat von Dan Zuras Intervals <intervals08@xxxxxxxxxxxxxx>:

This may be nitpicking, but 6.1 doesn't say anything about the
level 2
datum it describes as being represented. You might infer from the

        It says "An implementation may choose any means to
represent a
        level 2 interval datum..." & in the next paragraph "A
concrete
        interval format... (is a mapping) ...to an associated level
2
        format."

        That's all.

        Everything else is an informative note until you get to 6.2
        which is about containment in format conversion.

notation that this has to be an interval with bounds in F, but
that's
not explicit in the text, is it? Therefor my note that the text
itself

        You might make such an inference but, as you imply, it
would be
        inferring a bit too far.  The text says only "that it shall
be
        possible to retrieve the bounds of x exactly."

        Thus some form in which the bound may be recovered by, x +
eps
        or even x + x*eps would be acceptable so long as those
        operations can be performed exactly.

Isn't this and your later argument about the requirement on the sum in mid-rad formats exactly this inferring too much? I said "the note could be interpreted to define the nature of the level 2 datum having endpoints in F". You say that is inferring too much. The next step in my argument would be: well in this case the text doesn't define the nature of the level 2 datum and therefor doesn't require the bounds to be in F. The note on the triple representation uses a sum to represent each bound but doesn't say where the operation is to take place and what kind of result it should have, most importantly it doesn't require the sum to be executed in F. All of this comes IMHO from the definition of the level 2 datum. So probably if this Motion is referring to Section 5 of the standard that part has to be figured out before a final conclusion of this one---or this one has to be general enough to support an (in a limited way) arbitrary Section 5 (probably with minor adjustments).

On to the more fundamental issue...

  Christian