Fdhess.m

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Returns the finite-difference Hessian of a 3D array using a finite difference scheme with a user-specified number of stencil points. The dimensions of the 3D array are assumed to be ordered as [X Y Z]. Syntax:

                        H=fdhess(A,npoints)

where the second parameter specifies the number of points in the finite difference stencil that should be used. The result is a 3x3 cell array of 3D matrices ordered in the following way:

                  {d2A_dxdx  d2A_dxdy  d2A_dxdz
                   d2A_dydx  d2A_dydy  d2A_dydz
                   d2A_dzdx  d2A_dzdy  d2A_dzdz}