Thread Subject: matrix manipulation

Dear all,
            I need to create a matrix of size 256x256 .I want to put it in a loop.First I need to call 8x8 matrix(1:8,1:8) and fill all with same value.Next I have to call another 8x8 matrix (1:8,9:16) and fill all with same value (value is different from the first one).Similarly I need to complete entire matrix of size 256x256.Can anyone help me with matlab code for the same or give me an idea how to proceed.
Thanks

"kalyani sundaram" <kalyani@svce.ac.in> wrote in message <ipmbol$hg6$1@fred.mathworks.com>...
> Dear all,
> I need to create a matrix of size 256x256 .I want to put it in a loop.First I need to call 8x8 matrix(1:8,1:8) and fill all with same value.Next I have to call another 8x8 matrix (1:8,9:16) and fill all with same value (value is different from the first one).Similarly I need to complete entire matrix of size 256x256.Can anyone help me with matlab code for the same or give me an idea how to proceed.
> Thanks

Hi,

You could probably do it without a for loop, but here is a way with one

n=256;
A=zeros(n);
step=8;
k=0;
ll=n/step; %warning maybe?
values=1:(ll*ll); %input your values here

for ii=1:ll
    for jj=1:ll
      k=k+1;
      temp=values(k)*ones(step);
      A((ii-1)*step+1:ii*step,(jj-1)*step+1:jj*step)=temp;
    end
end

Regards,
Florin

"kalyani sundaram" <kalyani@svce.ac.in> wrote in message <ipmbol$hg6$1@fred.mathworks.com>...
> Dear all,
> I need to create a matrix of size 256x256 .I want to put it in a loop.First I need to call 8x8 matrix(1:8,1:8) and fill all with same value.Next I have to call another 8x8 matrix (1:8,9:16) and fill all with same value (value is different from the first one).Similarly I need to complete entire matrix of size 256x256.Can anyone help me with matlab code for the same or give me an idea how to proceed.
> Thanks

It's not clear why you're doing this with a loop if the values are repeated:

x=5;
m=zeros(8,8);
m(:,:)=x;

 >>m

m =

     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5
     5 5 5 5 5 5 5 5

Dear Florin,
Thanks for your timely help.The code works well for my project.
I am doing block processing in my project.How to write code for block processing with overlapping blocks.since by using the command 'blockproc' we can do non-overlapping block processing.
Thanks

Dear Barry,
      Thanks for your help.Could you please give me a code for dividing an image into blocks.(overlapping blocks).

"kalyani sundaram" <kalyani@svce.ac.in> wrote in message <iq2a94$hlr$1@newscl01ah.mathworks.com>...
> Dear Barry,
> Thanks for your help.Could you please give me a code for dividing an image into blocks.(overlapping blocks).

blockproc support overlapping blocks. go read the documentation.