Add conversion full_velocity to sparse_velocity.

lbmpy/sparse/mapping.py

@@ -167,6 +167,16 @@ class SparseLbMapper:
         index_arr = index_array.reshape([len(stencil) - 1, self.num_fluid_cells])
         index_arr = index_arr.swapaxes(0, 1) 
         return index_arr
+    
+    def set_velocity(self, full_vel_arr): #macht aus full_vel_arr einen sparse vel_arr
+        # Erstmal ghost layers von data_handling herausfinden und wegschneiden...
+        ghost_layers = [(full_vel_arr.shape[i] - self.domain_size[i])//2 for i in range(0, full_vel_arr.shape[-1])]
+        full_vel_arr = full_vel_arr[ghost_layers[0]:-ghost_layers[0], ghost_layers[1]:-ghost_layers[1]]
+        # Dann initial velocities in sparsen vector schreiben
+        fluid_cell_arr = self.coordinates
+        arr = fluid_cell_arr[:self.num_fluid_cells]
+        sparse_vel_arr = full_vel_arr[arr['x'], arr['y']]
+        return sparse_vel_arr
 
     
 class SparseLbPeriodicityMapper: