p_save Change Size on Every Loop Iteration

Hello, I wrote this code in Matlab and it sais that p_save change size on every loop iteration (p_save = [p_save p]), so I would like to improve it.

p_save = [];

syms ps

q = linspace(eps,150,60);

for i = 1 : length(q)

A_qs_flut = ps^2*q(i);

DA = det(A_qs_flut);

characteristic_equation = sym2poly(DA);

p = roots(characteristic_equation);

p_save = [p_save p];

end

I know that I can create an array with the right size and then substitute inside the values.

p_save = ones (4, length(q))

My question is: how can I substitute in a smart and fast way the p values inside the p_save array.

Thanks in advance.

Answer 1

[Fangjun Jiang]

p_save(:,i)=p

[Fabio Taccaliti]

Thanks for the answer, if instead I want to substitute for example p just in the first column and DA in the second and so on for other variables in the other columns what should I write?

p_save(:,1)=p

p_save(:,2)=DA

ecc.. ?

[Fangjun Jiang]

Yes. You would need declare p_save = ones (4, 2*length(q))

p_save(:,2*i-1)=p

p_save(:,2*i)=DA