disp_tree.m

决策树算法的matlab实现

function disp_tree(T,A,B)
% DISP_TREE displays the decision tree generated by the MSMT algorithm
%	by creating a graph of the tree and displaying the w,theta info
%	for each non-leaf node in the MATLAB environment
%
%	disp_tree(T,A,B)
%
%	T: matrix representing the decision tree 
%	A: matrix representing the point set A
%	B: matrix representing the point set B

global count;
count = 1;
% determine the depth of the tree:

[m,num_nodes] = size(T);
n = m - 4;

depth = 0;
for i = 1:num_nodes

	if (T(n+4,i) > depth)
		depth = T(n+4,i);
	end
end

% determine the size of the graph

xmax = 2^(depth-1);
xmin = 0;
ymax = depth + 2;
ymin = 0;

% open a plotting window
figure;

% turn the axis off
axis('off');

% set the axis
axis([ xmin xmax ymin ymax ]);

% hold these axis
hold on;

% determine the graph
dummy = [];
ystart = ymax - 1;
draw_tree(T,xmin,xmax,ystart,1);

% the graph is drawn
% nodes are numbered in depth-first fashion

% Now determine the breakdown matrix:
Tb = [];
Tb = msmt_tree_breakdown(Tb,T,A,B,1);


% now print out the pertinent information about the non-leaf nodes

% print out the header
disp(blanks(5)')
disp(['Plane:  wx = theta'])
disp(blanks(1)')
disp(['Node # ' ' ' '   ' 'w' blanks(8*n+1) 'theta   ' '  ' '# Pts. of A' '  ' '# Pts. of B' ])
count = 1;

disp(blanks(1)')

output_tree(T,Tb,1);