Directional derivative matrices for functions on meshes.

Calculates directional derivative matrices for functions on inla.mesh objects.

inla.mesh.deriv(mesh, loc)

Arguments

mesh

An inla.mesh object.

loc

Coordinates where the derivatives should be evaluated.

Value

A

The projection matrix, u(loc_i)=sum_j A_ij w_i

dx, dy, dz

Derivative weight matrices, du/dx(loc_i)=sum_j dx_ij w_i, etc.

Author

Finn Lindgren finn.lindgren@gmail.com