Re: List-Operations on Heads other than List
- To: mathgroup at smc.vnet.net
- Subject: [mg29743] Re: List-Operations on Heads other than List
- From: "Orestis Vantzos" <atelesforos at hotmail.com>
- Date: Fri, 6 Jul 2001 03:24:38 -0400 (EDT)
- Organization: National Technical University of Athens, Greece
- References: <9i068k$h0i$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
I don't really think there are "dangerous" programming styles. You do have ofcourse "ineffective" programming styles (such as using a horde of Part operations and For loops to mimic C in Mathematica) and there are "error-prone" programming styles (such as naming your favourite variable ASDADS12231). I think using Select on general structures(not just _List) is fairly safe; do keep in mind though, that Select searches in all the levels of your expression and you might get weird results because of this. Orestis "Detlef Mueller" <dmueller at mathematik.uni-kassel.de> wrote in message news:9i068k$h0i$1 at smc.vnet.net... > Hello, > > The Help Browser says: > > Select[list, crit] picks out all elements ... > > Now this works fin for other Haeders thal List > too. > > Select[Expand[P], ! NumberQ[#] &] removes the > absolute Part of the Poynomial P > (in my Version). > > Is this a dangerous Way of Programming? > > Greetings > Detlef >