[eeps] : Proposal for /\ and \/ operators

Pierpaolo Bernardi <>
Thu Feb 26 11:28:06 CET 2009


On Thu, Feb 26, 2009 at 11:12 AM, Raimo Niskanen <
 <raimo%>> wrote:

> On Thu, Feb 26, 2009 at 10:55:34AM +0100, Pierpaolo Bernardi wrote:
> > On Thu, Feb 26, 2009 at 10:35 AM, Raimo Niskanen <
> >  <raimo%> <
> raimo% <raimo%>>> wrote:
> >
> >
> > > Can you explain to a non-mathematician (me) why you have defined
> > > (E1 /\ E2) as min(E1, E2) and
> > > (E1 \/ E2) as max(E1, E2). To me it seems counterintuitive
> > > since /\ looks like a mountain hence max
> > > and \/ looks like a valley hence min.
> > > And I do not want to fully understand Lattice theory
> > > to understand which operator is which. I am a simple programmer.
> >
> >
> > It's not ROK's invention it's common mathematical usage (derived from
> > Boolean algebra, I think).
> >
> > The symbol  \/ derives from the letter V, abbreviation of "vel" (= or in
> > latin).
> >
> > I'm not sure where /\ comes from (maybe an inverted V?)
>
> Yes I am quite familiar with /\ being AND and \/ being OR.
> That is in the basic math courses at University.


I meant, it's common to use these symbols for min and max,
like they are used in boolean algebra.

In an algebra on the values true and false, where true and false are
ordered,
with false < true, the operation OR is the same as MAX and AND is the same
as MIN.

(Think false = 0, true = 1, and all will snap in place :)

P.
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