Dear Khani, The function discretizing the continuous Hamiltonian works for a hamiltonian with a polynomial form in the variables kx, ky, kz, which is not the case in your Hamiltonian.
What you can do is: 1) A Taylor expansion of your Hamiltonian, preferably to the second order. 2) Use the descritizing function of kwant with the Hamiltonian obtained by the expansion. (you can play with the order of the expansion too) 3) Check that it gives the form of your initial discretized Hamiltonian. This is not guaranteed to work all the time, but it is the fastest way in my opinion. I hope this helps, Adel On Fri, Aug 7, 2020 at 11:45 AM Khani Hosein <hoseinkhani...@gmail.com> wrote: > Dear authors, > I want to discretize continuous Hamiltonians of Weyl semimetal (PRL > 115,246603 (2015)) using Kwant, but we have sin(kz),sin(ky)...in the > Hamiltonian, so it always shows the error message. I have already imported > sin and cos from math. Could you give me any suggestion? > Hosein Khani > -- Abbout Adel