Plotting eigenvalues of a 4*4 matrix: In an assignment A(I) = B, the number of elements in B and I must be the same.

p=1;

for k=0.1:.1:3

A=[0 0 0 exp(-i*k);exp(i*k) 0 0 0;0 exp(i*k) 0 0;0 0 exp(i*k) 0];

C=eig(A);

x(p)=k;

y(p)=C;

p=p+1;

end

plot(x,y)

Answer 1

[Bhanu Prakash]

Hi Zahid,

As per my understanding, you are trying to plot the eigen values of a 4x4 matrix and are facing some error with it.

To perform an assignment operation, the dimensions of the matrices must be equal. For any given iteration, the matrices "C" & "y" have the dimensions 4x1 & 1x1 respectively, making the dimensions incompatible.

One workaround for this, is to change the indices of the matrix "y" as shown below:

y(:,p)=C;

You can refer to the documentation of array indexing, for more info:

Array Indexing - MATLAB & Simulink - MathWorks India

Hope this answer helps you.

Thanks,

Bhanu Prakash.

[ZAHID MALIK]

It worked, thank you so much