MATLAB Central Newsreader - use of matrix repeatedly

use of matrix repeatedly

munir — Tue, 03 Nov 2009 22:20:43 -0500

hi
i want to assemble a new matrix in which same submatrix is repeated
many times.
for example k=[1,2;2,1]
if m=1
ka=[k]
if m=2
ka=[k,k;k,k]
if m=3
ka=[k,k,k;k,k,k;k,k,k]
and so on....
how can i accomplish this task?????
plz help if possible.
thanks n regards.

Re: use of matrix repeatedly

Matt Fig — Tue, 03 Nov 2009 22:30:17 -0500

See the help for repmat.

Re: use of matrix repeatedly

Loren Shure — Thu, 05 Nov 2009 15:55:38 -0500

In article <10da359e-f86e-496d-b2d4-a171b447d346
@h14g2000pri.googlegroups.com>, munirpansare@gmail.com says...
> hi
> i want to assemble a new matrix in which same submatrix is repeated
> many times.
> for example k=[1,2;2,1]
> if m=1
> ka=[k]
> if m=2
> ka=[k,k;k,k]
> if m=3
> ka=[k,k,k;k,k,k;k,k,k]
> and so on....
> how can i accomplish this task?????
> plz help if possible.
> thanks n regards.
>

Another poster mentioned repmat. Maybe you don't even need the full
array, but to operate with it. If so, bsxfun might be able to help.

--
Loren
http://blogs.mathworks.com/loren

Re: use of matrix repeatedly

Bobby Cheng — Thu, 05 Nov 2009 16:28:19 -0500

What are you going to do with the result? Do you have to form the matrix?
---Bob.

"Loren Shure" <loren.shure@mathworks.com> wrote in message
news:MPG.255cbf8175b9216e989a5f@news.mathworks.com...
> In article <10da359e-f86e-496d-b2d4-a171b447d346
> @h14g2000pri.googlegroups.com>, munirpansare@gmail.com says...
>> hi
>> i want to assemble a new matrix in which same submatrix is repeated
>> many times.
>> for example k=[1,2;2,1]
>> if m=1
>> ka=[k]
>> if m=2
>> ka=[k,k;k,k]
>> if m=3
>> ka=[k,k,k;k,k,k;k,k,k]
>> and so on....
>> how can i accomplish this task?????
>> plz help if possible.
>> thanks n regards.
>>
>
> Another poster mentioned repmat. Maybe you don't even need the full
> array, but to operate with it. If so, bsxfun might be able to help.
>
> --
> Loren
> http://blogs.mathworks.com/loren
>

Re: use of matrix repeatedly

Sebastian Arslanogullari — Thu, 05 Nov 2009 19:11:02 -0500

This could be done in several ways, e.g.
k2=repmat(k,m,m);
or you can use kronecker tensor product:
k2 = kron(ones(m),k);
Regards
Sebastian