Re: silly problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg85301] Re: silly problem*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Tue, 5 Feb 2008 19:39:33 -0500 (EST)*Organization*: The Open University, Milton Keynes, UK*References*: <fo9g1h$sbm$1@smc.vnet.net>

Francis Bitonti wrote: > I'm new to Mathematica so this is a very basic question I think. but one > that has me hung up. I keep getting this error > > Set::write: Tag List in {0,0,0,0,0,0,0,0}[1] is Protected. >> > > > my code looks like this. > > *IN:* > For[i = 1, i < 6 , i++, > Print[ > g = i; > k[g] = twoDcalc[e1, a1, nodes[[{edges[[g, 1]], edges[[g, 2]]}]]]]] The following should work as expected: k[[g]] = twoDcalc[e1, a1, nodes[[{edges[[g, 1]], edges[[g, 2]]}]]]]] From what I could infer form the code you posted, the array 'k' was defined as a list of values. In this case one must use the *Part* function (or [[...]]) to read or modify the value at a specific location or index. See http://reference.wolfram.com/mathematica/ref/Part.html Regards, -- Jean-Marc