Re: Matrix expansion
- To: mathgroup at smc.vnet.net
- Subject: [mg47730] Re: Matrix expansion
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Sat, 24 Apr 2004 04:15:27 -0400 (EDT)
- Organization: Universitaet Leipzig
- References: <c6aei8$3gg$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
can you be more specific *what* you have done ?
Because with:
mat=Table[{dx[i],dy[j]},{i,3},{j,3}];
newrow=Table[{dx[4],dy[j]},{j,3}];
and
AppendTo[mat,newrow]
work fine.
Regards
Jens
Larry Caruso wrote:
>
> I have a large, square matrix where each m[[ i, j ]] is populated with f [
> i, j ], which happens to be a list {dx, dy}. At some later date, having
> collected more data, I want to expand matrix this to a larger square matrix
> using the same f [ i, j ] without losing any previously stored information.
> Since the matrix is huge, regenerating it takes far too long, so I want to
> simply add on the new data. I've tried experimenting with AppendRows[] and
> other routines, but they only operate on non-lists. As far as I can
> determine, using a C compiler with Mathlink may be my only option where I'm
> regenerating the matrix from scratch as quickly as possible instead of
> adding only new data.
>
>
>
> Are there any other reasonable possibilities? Thanks.