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Re: KISS-decorations



Yes, in this context, one is looking either at the topology over the
reals, or that topology restricted to, say [1,3/2].  Whichever way
we go with the floor function, I think we can explain it in such
terms.  What is the practical impact of one way over the other?

Baker

On 07/02/2011 09:07 AM, Kreinovich, Vladik wrote:
Of course, the notion of contnuity depends on topology, but when people
talk about continuity without explaining what this means, they mean continuity in the normal calculus epsilon-delta sense in which the floor function is clearly NOT continuous.

________________________________________
From: stds-1788@xxxxxxxx [stds-1788@xxxxxxxx] On Behalf Of Nate Hayes [nh@xxxxxxxxxxxxxxxxx]
Sent: Friday, July 01, 2011 3:37 PM
To: Jürgen Wolff von Gudenberg
Cc: John Pryce; Dominique Lohez; stds-1788@xxxxxxxx
Subject: Re: KISS-decorations

I'm thinking along the lines of Definition 2.2.3 on pp. 55-56 in:
     http://ramanujan.math.trinity.edu/wtrench/texts/TRENCH_REAL_ANALYSIS.PDF
By that definition, wouldn't
     floor([1,3/2])
be continuous?

Nate


----- Original Message -----
From: "Jürgen Wolff von Gudenberg"<wolff@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
To: "Nate Hayes"<nh@xxxxxxxxxxxxxxxxx>
Cc: "John Pryce"<j.d.pryce@xxxxxxxxxxxx>; "Dominique Lohez"
<dominique.lohez@xxxxxxx>; "stds-1788@xxxxxxxx"<stds-1788@xxxxxxxx>
Sent: Friday, July 01, 2011 2:59 PM
Subject: Re: KISS-decorations


Nate

Am 01.07.2011 17:09, schrieb Nate Hayes:
One other comment:

What about
floor([1,3/2])?
I would think it should be defined and continuous, i.e., "safe", since
when
restricted to the domain [1,3/2] the floor function at 1 is defined and
continuous when approached from the right and cannot be approached from
the
left.

But it seems this would imply
floor([1,1])
should also be "safe"; but motion 27 gives "defined" for this example?

Nate

I think 1 is a discontinuity point of the floor function, hence both cases
are defined only
Juergen




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