variable of arbitrary size

Hi I am a newbie in MATLAB. THis is my function which is similar to quadprog but in much smaller scale. "function [ x,fval ] = apple( Q,A,b,lb,up,x0)" my fval is x'*Q'x and my problem is that for any matrix Q(n*n) I need to have vector X=[X1;X2;X3....;Xn]. how can I initialize X of having corresponding size to n. x0 can also be inputted which might be helpful in creating X however x0 is not variable and has values.

I am stuck can anyone please help me with that.Thank you in advance

Answer 1

[Walter Roberson]

X = zeros(n, 1);