fdlap.m

Returns a finite-difference representation of the Laplacian for an array with a user-specified finite difference stencil size. The resulting operator is a sparse matrix designed to act on the vectorisation of the array. The dimensions of the array are assumed to be ordered as [X Y Z].

Syntax

L=fdlap(dims,extents,nstenc)

Arguments

dims - a one-element, two-element, or three-element

               vector specifying the number of discretisation
               points in each dimension of the 1D, 2D, or 3D
               array of data that the operator will be acting
               on, ordered as [X Y Z].

    extents -  a one-element, two-element, or three-element 
               vector specifying the size of each dimension
               of the array, ordered as [X Y Z].

    nstenc  -  number of finite-difference stencil points for
               the finite-difference approximation; periodic
               boundary conditions are used

Outputs

L - a sparse matrix designed to act on the vectori-

               zation of the 3D array. The dimensions of that
               array are assumed to be ordered as [X Y Z].

See also

fdvec.m, fdmat.m, fdhess.m, fdkup.m, fdweights.m, fftdiff.m, fourdif.m, fourlap.m

Version 2.2, authors: Ilya Kuprov