Re: opposite of AppendTo

*To*: mathgroup at smc.vnet.net*Subject*: [mg124345] Re: opposite of AppendTo*From*: Tomas Garza <tgarza10 at msn.com>*Date*: Tue, 17 Jan 2012 03:28:40 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <201201162212.RAA15438@smc.vnet.net>

If I understand correctly, your problem seems to lie in the use of AppendTo. This is a very tricky function, since it "resets" s without your control and sometimes things get messed up. Perhaps you could try to use simply Append, where you get a new list but s is not changed in the process. Essentially, what AppendTo does is s = Append[s,e]. -Tomas > Date: Mon, 16 Jan 2012 17:12:16 -0500 > From: burket at mailbox.sc.edu > Subject: opposite of AppendTo > To: mathgroup at smc.vnet.net > > AppendTo[s,e] appends "e" to "s" and then RESETS "s". How does one > delete or remove an element "e" from a list "s" and then RESET "s"? > The _reset_ is my problem. I want to be able to add and delete > elements of a list (a list of graphical elements with very low > opacity). I can "appendto" the list at will but am unable to delete > elements (using Delete, DeleteCases, Except, Select, etc.). Deleting > "e" from "s" is easy enough, but resetting "s" seems impossible. > Help!! >

**References**:**opposite of AppendTo***From:*burke <burket@mailbox.sc.edu>