pschindler

@PriyanshuPansari I have a (very inefficient) code that works somewhat for this. I ran into some issues with calculating the eigenstates (see #1998) which is the reason for the many...

I see a similar issue with just calculating the eigenstates of a simple $\sigma_x \otimes \sigma_x$ operator ``` python import qutip as q import scipy op = q.tensor(q.sigmax(), q.sigmax()) eigv_sp,...

Hi @Ericgig Thank you for the clarification. You are right for the $\sigma_x \otimes \sigma_x$ operator, the eigenvectors span indeed the same space. I stumbled upon weird behavior of `eigenstates()`...

Hi @AGaliciaMartinez . Good to hear from you again ;) It seems that the hermitian check for the operator `op` evaluates as `True` ```python qutip.cy.spmath.zcsr_isherm(op.data) == True ```

Also, if I add `op.isherm = False` to manual set `isherm` it seems to work: ```python import qutip as q import scipy max_n = 6 op = 0 for i...