Euklid (Inverse) Distance Weight Matrix

Calculates a weight matrix of any size using the (inverse) euklidean distance from center cell.

function W = euklid_W(ws,d,n)
function W = euklid_invW(ws,d,n)
% PURPOSE: create an (inverse) euklidean distance spatial weight matrix
% (n x m 'moving-window' style matrix with distance to center cell
% weighted.)
% ------------------------------------------------------------------
% USAGE: W = euklid_W([wsy wsx],[dy dx],n)
% where: ws is a vector [wsy wsx] of the x and y size of the matrix (uneven!)
% d (optional) is a vector [dy dx] of the cellspacing in y and x direction
% (default 1)
% [n] (optional) specifies how to normalize the weight matrix.
% Options for [n] are:
% 1) 'norm' to create a normalized weight matrix (sum of all
% weights is 1
% 2) 'none' or NA for a non-normalized matrix (default)
% -------------------------------------------------------------------------
% OUTPUTS:
% [W] a matrix with weights for every cell except center.
% -------------------------------------------------------------------
% NOTES: Weights are the the euklidean distance to
% the center cell. Center cell weight is zero.