How to extract only first few values of step function and perform arithmetic operations on those values?

yr(i1,:) = step(tf1) - error part

    for i2 = 1:N
        yy(i1,i2) = yr(i1,i2)
    end
    j(i1,1:N) = (y0(1,:) - yy(i1,:)).^2 - error part
    J(i1) = sum(j(i1))
Result of yr is a huge set of 1128 columns of values out of which i only want the first 10 or so and then how to subtact the corresponding of the set from another set and square the obtained results.

[Stephen23]

Some more informative and relevant Tags might create more interest in your question:

http://www.mathworks.com/matlabcentral/answers/43073-a-guide-to-tags

http://www.mathworks.com/matlabcentral/about/answers/

Answer 1

[Sarah]

From what I understand of your question, you need only the first 10 columns of yr. If this is so, then I would run my loop only 10 times and store the values of the columns in another vector. Then I can perform whatever operations I need with it.

for i=1:10 vector(:,i)=yr(:,i) end