Im getting an error as following while calculating the eigen values . Please help me urgently.

code:

Zr=zeros(4,4);
Id=eye(4,4);
i=sqrt(-1);

Xtemp=double([-i.*Kuu,-Kut,Zr;Zr,-Ktt,Zr;Zr,Zr,Id]);
X=vpa(Xtemp);

Ytemp=double([Zr,Zr,Muu;(1*Ctu),(1*Ctt),Zr;(1*Id),Zr,Zr]);
Y=vpa(Ytemp);
sol=polyeig(X,Y);
2*imag(sol)/real(sol)

error:Warning: Rank deficient, rank = 0, tol =
1.#INF00e+00.

K,M and C matrices are 4 by 4 matrices.

[John D'Errico]

http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency

Sorry, but everybody wants an answer ASAP. Do you think people post with a question that they don't care when it gets answered?

Your problem is singular. What help do you expect someone to provide? Formulate a non-singular problem. I can't even test your code, because most of the variables are undefined.