Re: Re: problem with Pick
- To: mathgroup at smc.vnet.net
- Subject: [mg78492] Re: [mg78409] Re: problem with Pick
- From: DrMajorBob <drmajorbob at bigfoot.com>
- Date: Tue, 3 Jul 2007 05:24:32 -0400 (EDT)
- References: <acbec1a40706230431p4f1db9a9i4320680dda027396@mail.gmail.com> <200707010731.DAA01680@smc.vnet.net> <3793885.1183353014400.JavaMail.root@m35>
- Reply-to: drmajorbob at bigfoot.com
Yeah, yeah, I know... the "2nd-order" explanation talks about list[[i1,12,...]], and Sequence[] is a (degenerate) example of i1,i2,..., so... Right. That's totally obvious. At least Andrzej (unlike Oyvind) told Chris how to avoid the top-level match. Bobby On Mon, 02 Jul 2007 00:05:38 -0500, Andrzej Kozlowski <akoz at mimuw.edu.pl> wrote: > *This message was transferred with a trial version of CommuniGate(tm) > Pro* > > On 1 Jul 2007, at 16:31, Chris Chiasson wrote: > >> On Jun 29, 4:40 am, J=E1nos <janos.l... at yale.edu> wrote: >>> Like barbers who are shaving themselves... :) >>> >>> J=E1nos >>> P.S. I am hearing someone turning slowly in his grave.... >>> >>> On Jun 28, 2007, at 4:26 AM, DrMajorBob wrote: >>> >>>> That's entirely contrary to the documentation, which says that Pick >>>> "picks >>>> out those ELEMENTS of list for which the corresponding ELEMENT of >>>> sel is >>>> True." >>> >>>> How is a list its own ELEMENT, if English words mean anything? >>> >>>> Bobby >> >> LOL >> >> > > Actually, there is nothing at all unusual about barbers shaving > themselves. I am sure lots of barbers do it. Russell's illustration (of > a variant of his paradox) was about a barber who "shaved everyone in > town who did not shave himself". It would take more than all the > resourcefulness of Figoro, the barber of Seville, to relate this to this > description of the behaviour of Pick, also taken from the documentation: > > Pick[list,sel,patt] picks out those list[[i1,i2,â?¦]] for which sel > [[i1,i2,â?¦]] matches patt. > > Now, this is a pretty straight forward statement which describes > precisely the behaviour of Pick - but I am afraid it's not likely to > generate any more feats of philosophical depth and wit. > > I do agree that the statement quoted by Bobby can mislead those who > insist on taking everything at face value but it was only meant as a > "first order approximation" and it is enough to dig a little deeper into > the documentation to see that the behaviour of Pick that Chris objected > to is in fact clearly documented. > > Andrzej Kozlowski > > > > -- DrMajorBob at bigfoot.com
- References:
- Re: problem with Pick
- From: Chris Chiasson <chris.chiasson@gmail.com>
- Re: problem with Pick