Re: Disappearing variables
- To: mathgroup at smc.vnet.net
- Subject: [mg13800] Re: [mg13759] Disappearing variables
- From: "Jurgen Tischer" <jtischer at col2.telecom.com.co>
- Date: Fri, 28 Aug 1998 04:18:23 -0400
- Sender: owner-wri-mathgroup at wolfram.com
Hi Vilis, I don't want to give the impression of the wise guy, I just fooled around a bit. So: 1. Help on Remove says: "If you have an expression that contains a symbol which you remove, the removed symbol will be printed as Removed["name"], where its name is given in a string. " 2. If you look at f after you removed x, it shows In[1]:= ?f "Global`f" f := Removed["x"] = 123 So that's it, the definition of f is an expression. If your question is not purely academic, maybe you could use Clear instead of Remove? Jurgen -----Original Message----- From: nobody at News.Dal.Ca <nobody at News.Dal.Ca> To: mathgroup at smc.vnet.net Subject: [mg13800] [mg13759] Disappearing variables >I want to to define a variable inside a function, as follows: f:=x=123; >Whenever I run f, x should be given the value of 123, and if x doesn't >exist, it should be created. However: > >In[1]:= f:=x=123; >In[2]:=f >Out[2]:=123 >In[3]:=x >Out[3]:=123 ** x exists >In[4]:=Remove[x]; >In[5]:=f >Out[5]:=123 ** f seems to work >In[6]:=x >Out[6]:=x ** x doesn't exist anymore, even though f worked > >It seems like x is created when I initially define f, whereas since f is >SetDelayed, x should be created when I run f. Does anyone know why x >is not created when I run f? > >Vilis Nams > > >