for loop with a spread

Hi guys,

I wanted to get an idea on how I should approach a problem. Say for example I have a 100x48 matrix and I want to get a new matrix that takes the 48th value substracts it by the 39th value and so on. So next would be the 47th value subtracted by the 38th value and for this to continue all the way until I reach the 1st value. This would be done for all rows. I believe at the end I would end up with a matrix of 100x39.

Any help would be truly appreciated it.

Answer 1

[darova]

use for loop

[m,n] = size(A);            % your matrix
A1 = zeros(m,n-9);          % new matrix preallocation
for i = 1:n-9
    A1(:,i) = A(:,n-i+1)-A(:,n-i-8);
end

[N/A]

Thank you for your answer. It's extremly helpful.

[darova]

my plesure