matlab大神帮帮忙!!!!!!!1

Devia = 0.01;
N = 300; N_tr = 100; N_ts = 300;
for i = 1 : N
tim(i) = 0.01 + i * (2-0.01)/N;
end
x1 = tim + NORMRND(0,Devia,1,N);
x2 = tim.^2 - 3*tim + NORMRND(0,Devia,1,N);
x3 = -tim.^3 + 3*tim.^2 + NORMRND(0,Devia,1,N);
x = [x1', x2', x3'];
x_tr = x(1:N_tr,:);
Ex = mean(x_tr); stdr = std(x_tr);
sr = (x_tr - repmat(Ex,N_tr,1))./repmat(stdr,N_tr,1);
m = size(sr,2);