Re: Variables Within Homemade Functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg69593] Re: Variables Within Homemade Functions*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Sun, 17 Sep 2006 06:57:02 -0400 (EDT)*Organization*: The Open University, Milton Keynes, UK*References*: <eegb90$lm$1@smc.vnet.net>

Gregory Lypny wrote: > Hello everyone, > > How can I ensure that variables in my home made function do not > conflict with variables with the same name outside the function? Say > I have a variable, t, whose value in my notebook is 17. I've brought > in a function from another notebook, myFunction, that contains a > variable named t, and in running the function, t will take on a > value. Unfortunately, both t's are the same. Is there any way to > make the t within the my function a local variable just like index > counters in the Table and Do functions? > > Regards, > > Greg > > t=17 > > myFunction[x_]:=(t=someOtherValue; rest of function here) > Gregory, Module [1] is your friend here: In[1]:= t = 17; myFunction[x_] := Module[ {t = someOtherValue}, Print["my local t is equal to ", t] ]; Print["t is equal to ", t]; myFunction[2]; Print["t is equal to ", t]; From In[1]:= t is equal to \[InvisibleSpace]17 From In[1]:= my local t is equal to \[InvisibleSpace]someOtherValue From In[1]:= t is equal to \[InvisibleSpace]17 Also, you should have a look at With and Block. Regards, Jean-Marc [1] http://documents.wolfram.com/mathematica/functions/Module