# discretize.CylindricalMesh.project_node_to_boundary_node#

property CylindricalMesh.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 $$\mathbf{u_b}$$ 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