matrix loop with changing rows and columns

Dear all,

I have written a loop but I want to tell matlab that it should avoid always a range of certain 56 columns, and add the same time switch to the next rows. I dont know why, but the second part of the sum won't work.

j=0;
em_emb= ones([44,1]);
while j<56;
    f_rs_i =sum(Z(1+j:56+j,1:2464-1+j:56+j),1);
    j = j+56;
    em_emb(j)= f_rs_i;
end

Thanks in advance

Answer 1

[Image Analyst]

What is Z? What is the range of columns you want to skip? Why not just do 2 nested for loops?

[rows, columns] = size(Z)
for row = 1 : rows
    for col = 1 : columns
        if col > col1 || col <= col2
            % Don't process these columns.
            continue;
        end
        % else this column is okay to process so do something.
    end
end

[Image Analyst]

Maybe you want to skip every 56th column:

[rows, columns] = size(Z)
j = 0;
for row = 1 : rows
    for col = 1 : columns
        if rem(col, 56) == 0
            % Don't process these columns that are multiples of 56
            continue;
        end
        % else this column is okay to process so do something.
        f_rs_i =sum(Z(1+j:56+j,1:2464-1+j:56+j),1);
        em_emb(j)= f_rs_i;
        j = j+56;
    end
end

[Victoria Pake]

Z is a matrix 2464x2464, i want to skip always 56 columns

[Image Analyst]

Then just start at column 57:

for row = 1 : rows
    for col = 57 : columns
        % Do stuff
    end
end