polaris.mesh.connectivity.has_active_vertex

polaris.mesh.connectivity.has_active_vertex(ds_mesh, cell_mask)[source]

Find the cells with at least one active vertex, meaning a vertex all of whose surrounding cells are in the domain.

A cell of the sea-ice domain needs one of these, or a B-grid has no velocity point by which ice can leave it.

Parameters:

ds_mesh (xarray.Dataset) – An MPAS mesh with cellsOnCell and nEdgesOnCell
cell_mask (numpy.ndarray or xarray.DataArray) – A boolean mask on cells that is True for cells in the domain

Returns:

has_vertex (numpy.ndarray) – A boolean array of shape (nCells,). Cells outside the domain are evaluated too; callers that care should mask the result.