def evolve(self):
"""
Evolve the linear advection equation through one timestep. We only
consider the "density" variable in the CellCenterData2d object that
is part of the Simulation.
"""
dtdx = self.dt / self.cc_data.grid.dx
dtdy = self.dt / self.cc_data.grid.dy
flux_x, flux_y = flx.unsplit_fluxes(self.cc_data, self.rp, self.dt,
"density")
"""
do the differencing for the fluxes now. Here, we use slices so we
avoid slow loops in python. This is equivalent to:
myPatch.data[i,j] = myPatch.data[i,j] + \
dtdx*(flux_x[i,j] - flux_x[i+1,j]) + \
dtdy*(flux_y[i,j] - flux_y[i,j+1])
"""
dens = self.cc_data.get_var("density")
dens.v()[:,:] = dens.v() + dtdx*(flux_x.v() - flux_x.ip(1)) + \
dtdy*(flux_y.v() - flux_y.jp(1))
# increment the time
self.cc_data.t += self.dt
self.n += 1
def evolve(self):
"""
Evolve the linear advection equation through one timestep. We only
consider the "density" variable in the CellCenterData2d object that
is part of the Simulation.
"""
dtdx = self.dt/self.cc_data.grid.dx
dtdy = self.dt/self.cc_data.grid.dy
flux_x, flux_y = flx.unsplit_fluxes(self.cc_data, self.rp, self.dt, "density")
"""
do the differencing for the fluxes now. Here, we use slices so we
avoid slow loops in python. This is equivalent to:
myPatch.data[i,j] = myPatch.data[i,j] + \
dtdx*(flux_x[i,j] - flux_x[i+1,j]) + \
dtdy*(flux_y[i,j] - flux_y[i,j+1])
"""
dens = self.cc_data.get_var("density")
dens.v()[:, :] = dens.v() + dtdx*(flux_x.v() - flux_x.ip(1)) + \
dtdy*(flux_y.v() - flux_y.jp(1))
if self.particles is not None:
myg = self.cc_data.grid
u = self.rp.get_param("advection.u")
v = self.rp.get_param("advection.v")
u2d = myg.scratch_array() + u
v2d = myg.scratch_array() + v
self.particles.update_particles(self.dt, u2d, v2d)
# increment the time
self.cc_data.t += self.dt
self.n += 1
