For-Loop to find combinations of springs

I need to use a for-loop in a function in order to find spring constants of all possible combinations of springs in series and parallel. I have 5 springs with data therefore I found the spring constant (K) of each in a new matrix by using polyfit to find the slope (using F=Kx).

I have created a function that does so, however it returns data not in a matrix, but as individual outputs. So instead of KP (Parallel)= [1 2 3 4 5] it says KP=1, KP=2, KP=3, etc. Because of this, only the final output is stored in my workspace. Here is the code I have for the function. Keep in mind that the reason I need to use the +2 in the for loop for b is because my original matrix K with all spring constants is ten columns, with every odd number being a 0. Ex: K=[1 0 2 0 3 0 4 0 5] --- This is because my original dataset to find K (slope) was ten columns wide.

function[KP,KS]=function_name1(K)
L=length(K);
c=1;
for a=1:2:L
    for b=a+2:2:L
        KP=K(a)+K(b)
        KS=1/((1/K(a))+(1/K(b)))
    end
end
c=c+1;

and then a program calling that function

[KP,KS]=function_name1(K);

What I tried: - Suppressing and unsuppressing lines of code (unsuccessful)

Any help would be greatly appreciated.

[Walter Roberson]

What shape of output are you expecting for KP and KS? Are you expecting an L x L matrix? An L/2 x L/2 matrix? an L * (L+1) / 2 vector packing together the triangular matrix of results? Where in KP do you want (first a, first b) to be stored? Where do you want (first a, second b) to be stored? Where do you want (second a, first b for second a) to be stored ?