how to shorten this equation?

Hello, I want to ask a question. I'm very new on MATLAB. I have a matrix called K. K(100,40) 100 rows and 40 columns. Matrix includes only 0 or 1. I wrote an equation like this:

İ=0; J=0;
for i=0:99
  form1(i+1,1)=K(i+1,j+1)+K(i+1,j+3)+K(i+1,j+5)+K(i+1,j+7)+K(i+1,j+9)+ ..... +K(i+1,j+39);

form2(i+1,1)=K(i+1,j+2)+K(i+1,j+4)+K(i+1,j+6)+K(i+1,j+8)+K(i+1,j+10)+ .... + K(i+1,j+40);
end

And my problem , for j is 1 to 40 so I'm writing too much code. How can I shorten this equation? Is there a way, please help me?

Answer 1

[Oleg Komarov]

Sum for each row the odd columns (form1) and the even columns (form2):

form1 = sum(K(:,1:2:end),2);
form2 = sum(K(:,2:2:end),2);

You don't need a loop.

Please read the Getting Started Guide and specifically: Indexing::Language Fundamentals

[Daniel Shub]

This doesn't make use of the logical (0 or 1) nature of K, but I cannot think of a loopless (no arrayfun either) one line solution that uses the logical aspect...

Answer 2

[Selin Soguksu]

Thank you very much for your answer. It works great :))