function s=nodes(tree)
%NODES Counts the number of nodes of a GPLAB algorithm tree.
% NODES(TREE) returns the number of nodes (functions and
% terminals) of a GPLAB algorithm individual representation tree.
%
% Input arguments:
% TREE - the tree to measure (struct)
% Output arguments:
% NNODES - the number of nodes of the tree (integer)
%
% See also INTRONNODES, TREELEVEL, MAKETREE
%
% Copyright (C) 2003-2007 Sara Silva (sara@dei.uc.pt)
% This file is part of the GPLAB Toolbox
nkids=size(tree.kids,2);
if nkids error('NODES: number of children lower than 0!');
end
s=1; % root of this subtree
if nkids>0
for i=1:nkids
s=s+nodes(tree.kids{i});
end
end
