Eigenvalues NaN and inf
Suppose I have a system AX = nBX where A and B are known martrices, X is the coefficient matrix.
I am solving this using Chebyshev polynomials.
BC's are u(-1)=0=u(1)
I am imposing the bc's for the first and last rows of matrices A and B.
e=solve(A,B) e=0 e[-1]=0 x=solve(A,e)
What is wrong with this?
The question you seem to be asking: how come a generalized eigenvalue problem has eigenvalues inf and nan?
Your generalized eigenvalue problem is singular and has eigenvalues lambda=alpha/beta such that (alpha=0, beta=0) and (alpha!=0, beta=0). Since eigvals reports the eigenvalues, they are 0/0=nan or x/0=inf, correspondingly.
If your problem shouldn't have such eigenvalues, then it's likely that there is an error in the construction of the matrices.