% HNORMALISE - Normalises array of homogeneous coordinates to a scale of 1%% Usage:  nx = hnormalise(x)%% Argument:%         x  - an Nxnpts array of homogeneous coordinates.%% Returns:%         nx - an Nxnpts array of homogeneous coordinates rescaled so%              that the scale values nx(N,:) are all 1.%% Note that any homogeneous coordinates at infinity (having a scale value of% 0) are left unchanged.% Peter Kovesi  % School of Computer Science & Software Engineering% The University of Western Australia% pk at csse uwa edu au% http://www.csse.uwa.edu.au/~pk%% February 2004function nx = hnormalise(x)        [rows,npts] = size(x);    nx = x;    % Find the indices of the points that are not at infinity    finiteind = find(abs(x(rows,:)) > eps);    if length(finiteind) ~= npts        warning('Some points are at infinity');    end    % Normalise points not at infinity    for r = 1:rows-1	nx(r,finiteind) = x(r,finiteind)./x(rows,finiteind);    end    nx(rows,finiteind) = 1;