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Re: Idempotence and "Replication Insensitivity" are equivalent ?

From: Aloha Kakuikanu <aloha.kakuikanu_at_yahoo.com>
Date: 22 Sep 2006 11:42:22 -0700
Message-ID: <1158950542.467333.172370@b28g2000cwb.googlegroups.com>


Jan Hidders wrote:
> You'd split that into computing (minDate, maxDate) and then do some
> post-processing. For (minDate, maxDate) you get:
> - E = (null, null)
> - S(d) = (d,d)
> - A((d1, d2), (d3, d4)) = (MIN(d1, d3), MAX(d2, d4))
> with MIN and MAX defined such that MIN(d, null) = MIN(null, d) = MAX(d,
> null) = MAX(null, d) = d.

This null thingy doesn't make sence:

MIN(MAX(d, null),null) = null (by absorption) MIN(MAX(d, null),null) = d (by applying your rule twice)

It is obvious that you are after neutral elements -oo and +oo such that

MIN(d, -oo) = -oo
MAX(d, -oo) = d
MIN(d, +oo) = d
MAX(d, +oo) = +oo
Received on Fri Sep 22 2006 - 13:42:22 CDT

Original text of this message

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