Hi Naveen,
kwant.continuum.discretize can only deal with k_{xyz} as polynomials.
Best, Bas
On Mon, Apr 1, 2019 at 8:00 AM Naveen Yadav naveengunwa...@gmail.com
<http://mailto:naveengunwa...@gmail.com> wrote:
Dear all,
>
> I am tring to discretize the Hamiltonian containing the functional terms
> (like sin(k_x) ), but I am getting an TypeError : 'Symbol' object is not
> callable.
> The code is
> from __future__ import division
> import kwant
> import kwant.continuum
> import scipy.sparse.linalg
> import scipy.linalg
> import numpy as np
> import sympy
> from math import sin, cos, sqrt, pi
> import matplotlib.pyplot as plt
> hamiltonian = ("""sigma_x * sin(k_x) + sigma_y * sin(k_y) +
> sigma_0*(k_z)""")
> hamiltonian = kwant.continuum.sympify(hamiltonian)
> template, coords = kwant.continuum.discretize_symbolic(hamiltonian)
> t = kwant.continuum.build_discretized(template, coords)
> print(t)
>
> TypeError Traceback (most recent call
> last)<ipython-input-5-2b66bb479997> in <module> 9 import
> matplotlib.pyplot as plt 10 hamiltonian = ("""sigma_x * sin(k_x) +
> sigma_y * sin(k_y) + sigma_0*(k_z)""")---> 11 hamiltonian =
> kwant.continuum.sympify(hamiltonian) 12 template, coords =
> kwant.continuum.discretize_symbolic(hamiltonian) 13 t =
> kwant.continuum.build_discretized(template, coords)
> /usr/local/lib/python3.6/dist-packages/kwant/continuum/_common.py in
> sympify(expr, locals) 197 # sympy types. 198 subs = {r:
> sympy.Symbol(str(r.func))(*r.args)--> 199 for r in
> hamiltonian.atoms(sympy.Function)} 200 201 hamiltonian =
> hamiltonian.subs(subs)
> /usr/local/lib/python3.6/dist-packages/kwant/continuum/_common.py in
> <dictcomp>(.0) 197 # sympy types. 198 subs = {r:
> sympy.Symbol(str(r.func))(*r.args)--> 199 for r in
> hamiltonian.atoms(sympy.Function)} 200 201 hamiltonian =
> hamiltonian.subs(subs)
> TypeError: 'Symbol' object is not callable
>
> Could you please help me in the above context.
>
> Thanks in Advance.
>
> Naveen
>
>
> --
>
>
> With Best Regards
> NAVEEN YADAV
> Ph.D Research Scholar
> Deptt. Of Physics & Astrophysics
> University Of Delhi.
>
