Matlab中出现Error using ==> .*

Matlab中出现Error using ==> .*
程序下：
n=2;
X=[1,2,3,4,5];
Y=[4,4,5,6,8,8.5];
W=[2,1,3,1,1];
N=length(X);
A=(X'*ones(1,n)).^(ones(N,1)*(0:1:n-1));
b=Y;
AA=A'*(A.*(W'*(ones(1,n))))
Ab=A'*(b'.*W')
C=AA^(-1)*Ab
t=X(1)-0.1*(X(N)-X(1)):0.1:X(N)+0.1*(X(N)-X(1));
plot(X,Y,'p',t,polyval([C(2),C(1)],t));grid;