revert advection files

pyro/advection/interface.py

@@ -7,6 +7,9 @@ def linear_interface(a, myg, rp, dt):
     u = rp.get_param("advection.u")
     v = rp.get_param("advection.v")
 
+    cx = u*dt/myg.dx
+    cy = v*dt/myg.dy
+
     # --------------------------------------------------------------------------
     # monotonized central differences
     # --------------------------------------------------------------------------
@@ -16,34 +19,25 @@ def linear_interface(a, myg, rp, dt):
     ldelta_ax = reconstruction.limit(a, myg, 1, limiter)
     ldelta_ay = reconstruction.limit(a, myg, 2, limiter)
 
-    ldelta_Fx = reconstruction.limit(u*a, myg, 1, limiter)
-    ldelta_Fy = reconstruction.limit(v*a, myg, 2, limiter)
-
-    # x-direction
     a_x = myg.scratch_array()
 
     # upwind
     if u < 0:
-        # a_x[i,j] = a[i,j] - 0.5*ldelta_ax[i,j] - 0.5*dt/dx*ldelta_Fx[i,j]
-        a_x.v(buf=1)[:, :] = a.v(buf=1) - 0.5*ldelta_ax.v(buf=1) \
-                                        - 0.5*dt/myg.dx*ldelta_Fx.v(buf=1)
-
+        # a_x[i,j] = a[i,j] - 0.5*(1.0 + cx)*ldelta_a[i,j]
+        a_x.v(buf=1)[:, :] = a.v(buf=1) - 0.5*(1.0 + cx)*ldelta_ax.v(buf=1)
     else:
-        # a_x[i,j] = a[i-1,j] + 0.5*ldelta_ax[i-1,j] - 0.5*dt/dx*ldelta_Fx[i-1,j]
-        a_x.v(buf=1)[:, :] = a.ip(-1, buf=1) + 0.5*ldelta_ax.ip(-1, buf=1) \
-                                             - 0.5*dt/myg.dx*ldelta_Fx.ip(-1, buf=1)
+        # a_x[i,j] = a[i-1,j] + 0.5*(1.0 - cx)*ldelta_a[i-1,j]
+        a_x.v(buf=1)[:, :] = a.ip(-1, buf=1) + 0.5*(1.0 - cx)*ldelta_ax.ip(-1, buf=1)
 
     # y-direction
     a_y = myg.scratch_array()
 
     # upwind
     if v < 0:
-        # a_y[i,j] = a[i,j] - 0.5*ldelta_ay[i,j] - 0.5*dt/dy*ldelta_Fy[i,j]
-        a_y.v(buf=1)[:, :] = a.v(buf=1) - 0.5*ldelta_ay.v(buf=1) \
-                                        - 0.5*dt/myg.dy*ldelta_Fy.v(buf=1)
+        # a_y[i,j] = a[i,j] - 0.5*(1.0 + cy)*ldelta_a[i,j]
+        a_y.v(buf=1)[:, :] = a.v(buf=1) - 0.5*(1.0 + cy)*ldelta_ay.v(buf=1)
     else:
-        # a_y[i,j] = a[i,j-1] + 0.5*ldelta_ay[i,j-1] - 0.5*dt/dy*ldelta_Fy[i,j-1]
-        a_y.v(buf=1)[:, :] = a.jp(-1, buf=1) + 0.5*ldelta_ay.jp(-1, buf=1) \
-                                        - 0.5*dt/myg.dy*ldelta_Fy.jp(-1, buf=1)
+        # a_y[i,j] = a[i,j-1] + 0.5*(1.0 - cy)*ldelta_a[i,j-1]
+        a_y.v(buf=1)[:, :] = a.jp(-1, buf=1) + 0.5*(1.0 - cy)*ldelta_ay.jp(-1, buf=1)
 
     return u, v, a_x, a_y

pyro/advection/simulation.py

@@ -52,14 +52,8 @@ def method_compute_timestep(self):
         v = self.rp.get_param("advection.v")
 
         # the timestep is min(dx/|u|, dy/|v|)
-        dx_min = np.min(self.cc_data.grid.V() / \
-                        self.cc_data.grid.A_x())
-
-        dy_min = np.min(self.cc_data.grid.V() / \
-                        self.cc_data.grid.A_y())
-
-        xtmp = dx_min/max(abs(u), self.SMALL)
-        ytmp = dy_min/max(abs(v), self.SMALL)
+        xtmp = self.cc_data.grid.dx/max(abs(u), self.SMALL)
+        ytmp = self.cc_data.grid.dy/max(abs(v), self.SMALL)
 
         self.dt = cfl*min(xtmp, ytmp)
 
@@ -70,7 +64,8 @@ def evolve(self):
         is part of the Simulation.
         """
 
-        myg = self.cc_data.grid
+        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", linear_interface)
 
@@ -85,14 +80,8 @@ def evolve(self):
 
         dens = self.cc_data.get_var("density")
 
-        dens.v()[:, :] = dens.v() + self.dt / myg.V() * \
-                         (myg.A_x()*flux_x.v() - myg.A_x(1)*flux_x.ip(1) + \
-                          myg.A_y()*flux_y.v() - myg.A_y(1)*flux_y.jp(1))
-
-
-        # dens.v()[:, :] = dens.v() \
-        #     + dtdx*(flux_x.v() - flux_x.ip(1)) + \
-        #                             dtdy*(flux_y.v() - flux_y.jp(1))
+        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