discretize.TensorMesh.project_node_to_boundary_node#

property TensorMesh.project_node_to_boundary_node#

Projection matrix from all nodes to boundary nodes.

Constructs and returns a matrix $\mathbf{P}$ that projects from all mesh nodes to boundary nodes. That is, for a discrete scalar $\mathbf{u}$ that lives on the nodes, the values on the boundary nodes ${\mathbf{u}}_{\mathbf{b}}$ can be extracted via the following matrix-vector product:

ub = P @ u

Returns:

(n_boundary_nodes, n_nodes) scipy.sparse.csr_matrix

Projection matrix with shape