Re: Replacing elements in matrix.
- To: mathgroup at smc.vnet.net
- Subject: [mg29350] Re: Replacing elements in matrix.
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Thu, 14 Jun 2001 02:27:27 -0400 (EDT)
- References: <9g74fa$cg6$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Yoram,
Three suggestions:
Mat = Table[1,{5},{5}]
{{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1}}
ReplacePart[Mat,{0},{{2,2},{2,3},{2,4}},{1}]
{{1,1,1,1,1},{1,0,0,0,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1}}
Block[{m=Mat},m[[{2},{2,3,4}]]=0;m]
{{1,1,1,1,1},{1,0,0,0,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1}}
So far the value of Mat has not changed
Mat
{{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1}}
Here we change its value:
Mat[[{2},{2,3,4}]]=0;Mat
{{1,1,1,1,1},{1,0,0,0,1},{1,1,1,1,1},{1,1,1,1,1},{1,1,1,1,1}}
--
Allan
---------------------
Allan Hayes
Mathematica Training and Consulting
Leicester UK
www.haystack.demon.co.uk
hay at haystack.demon.co.uk
Voice: +44 (0)116 271 4198
Fax: +44 (0)870 164 0565
"Yoram Pollack" <syftech at saad.org.il> wrote in message
news:9g74fa$cg6$1 at smc.vnet.net...
> Hello there,
> what will be the best way to replace a few successive elements in one row
in
> a matrix (but not the whole row)?
> For example, in 5x5 matrix, replace elements 2,3,4 of row 2 by {0,0,0}.
> Many thanks
> Yoram
>
>
>