splinepy.multipatch.Multipatch.interfaces

property Multipatch.interfaces

Determine the interfaces of a given multipatch system

Returns its interfaces in the form as an array of size n_patches x n_sides_per_patch

The interfaces are stored as indices. If the index is negative, the ID is referring to a boundary (e.g. for boundary conditions). If the number is positive, the ID refers to the global face-id, which is composed of the element ID and the local face ID : global_face = local_face + number_of_faces_per_element * element_id

Example:

O -- 3 -- O O -- 3 -- O
|         | |         |
0    0    1 0    1    1
|         | |         |
O -- 2 -- O O -- 2 -- O

would be stored as:

[
  [-1, 4, -1, -1],
  [1, -1, -1, -1]
]

Returns:

interfaces – inter-patch connectivitiy and boundaries

Return type:

np.ndarray