# Authors:
#     Loic Gouarin <loic.gouarin@polytechnique.edu>
#     Benjamin Graille <benjamin.graille@math.u-psud.fr>
#
# License: BSD 3 clause

"""
Example of a D3Q6 for advection
"""
from six.moves import range
import sympy as sp
import pylbm
u, X, Y, Z = sp.symbols('u, X, Y, Z')

cx, cy, cz = .1, -.1, .2
d = {
    'dim': 3,
    'scheme_velocity': 1.,
    'schemes': [{
        'velocities': list(range(1,7)),
        'conserved_moments': u,
        'polynomials': [1, X, Y, Z, X**2-Y**2, X**2-Z**2],
        'equilibrium': [u, cx*u, cy*u, cz*u, 0., 0.],
        'relaxation_parameters': [0., 1.5, 1.5, 1.5, 1.5, 1.5],
    },],
}
s = pylbm.Scheme(d)
print(s)