Re: Did something change?
- To: mathgroup at smc.vnet.net
- Subject: [mg58120] Re: [mg58109] Did something change?
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sun, 19 Jun 2005 03:43:23 -0400 (EDT)
- Reply-to: hanlonr at cox.net
- Sender: owner-wri-mathgroup at wolfram.com
Do[F[i]=IdentityMatrix[8];
F[i]=ReplacePart[F[i], 7, {1,3}],{i,10}];
or
Do[F[i]=
ReplacePart[IdentityMatrix[8], 7, {1,3}],
{i,10}];
Bob Hanlon
>
> From: Ronald Bruck <bruck at math.usc.edu>
To: mathgroup at smc.vnet.net
> Date: 2005/06/18 Sat AM 06:08:27 EDT
> Subject: [mg58120] [mg58109] Did something change?
>
> Recently I created a list of several matrices, something like
>
> Do[F[i] = IdentityMatrix[8]; F[i][[1,3]] = 7, {i,10}]
>
> and was surprised to get the message that F[i] wasn't a symbol. I'm
> pretty sure code similar to that worked prior to Mathematica 5. Did
> something change?
>
> I've also tried Symbolize[F[i]] in that loop, but it doesn't help;
> Mathematica refuses to access part [[1,3]] of F[i], claiming F[i] isn't
> a symbol.
>
> How are you supposed to set the individual values of a matrix if you
> can't do this? This is an EXTREMELY unhelpful "feature".
>
> --Ron Bruck
>
>