Re: Warsaw Univ. course, was Re: Work on Basic Mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg131026] Re: Warsaw Univ. course, was Re: Work on Basic Mathematica*From*: Richard Fateman <fateman at eecs.berkeley.edu>*Date*: Tue, 4 Jun 2013 02:01:24 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-outx@smc.vnet.net*Delivered-to*: mathgroup-newsendx@smc.vnet.net*References*: <kmngb2$3rv$1@smc.vnet.net> <20130519095011.606CD6A14@smc.vnet.net> <knv52t$j93$1@smc.vnet.net> <ko1nhc$r3t$1@smc.vnet.net> <ko9ito$kf1$1@smc.vnet.net> <20130601102708.D06EF6A07@smc.vnet.net> <CA+mE4FvOwVNbZrzQS89H0JT7-Osp_1qTOqfSei0QHXmZdagsjg@mail.gmail.com>

On 6/3/2013 9:25 AM, Leonid Shifrin wrote: <long message> Thanks for what I consider a most agreeable contribution. I was not aware of your material on stackexchange, which seems to be rather nice. You are right that my example regarding mutable Lists in Mathematica was incorrect. Actually on two grounds. The syntax was not right and I did not mean to say that Lists in Mathematica are not mutable, since they certainly are. Just that Lists have the uncomfortable property that if you access one element, all the others are re-evaluated. Here is an example, which I think is free of mis-used syntax... ( q=Table[f[i],{i,1,3}]; f[n_]:=(Print[n];g[n])) q[[2]] evaluates to display 1 2 3 g[2] Changing q by, for example, q[[2]]=hello does not re-evaluate the elements. However, referring to in again as q[[2]] does this: 1 3 hello Thanks for pointing out the original error. RJF

**References**:**Re: Warsaw Univ. course, was Re: Work on Basic Mathematica Stephen!***From:*Richard Fateman <fateman@cs.berkeley.edu>