how can we preallocate a 2d array?

there is a warning in my program, it says that the variable is growing inside a loop. so consider pre allocation for speed

Answer 1

[Razvan]

See here some examples: http://www.mathworks.com/support/solutions/en/data/1-18150/

Answer 2

[José Jines]

Hi,

I am trying to solve this equation:

q_rad_L(i,j)=(ew./(a_g_p+ew-a_g_p).*ew).*thau.*(e_g_p.*T_ini.^4 -a_g_p.*T_iw.^4).*(a_hat./(x(i)-x(i-1)));

I want to solve to some values: i=1:15, j=1:15 into a loop.

I will appreciate for any response.

Josh