marg_table.m

来自「用matlab实现贝叶斯网络的学习、推理。」· M 代码 · 共 28 行

function smallT = marg_table(bigT, bigdom, bigsz, onto, maximize)
% MARG_TABLE Marginalize a table
% smallT = marg_table(bigT, bigdom, bigsz, onto, maximize)

if nargin < 5, maximize = 0; end


smallT = myreshape(bigT, bigsz); % make sure it is a multi-dim array
sum_over = mysetdiff(bigdom, onto);
ndx = find_equiv_posns(sum_over, bigdom);
if maximize
  for i=1:length(ndx)
    smallT = max(smallT, [], ndx(i));
  end
else
  for i=1:length(ndx)
    smallT = sum(smallT, ndx(i));
  end
end


ns = zeros(1, max(bigdom));
%ns(bigdom) = mysize(bigT); % ignores trailing dimensions of size 1
ns(bigdom) = bigsz;

smallT = squeeze(smallT); % remove all dimensions of size 1
smallT = myreshape(smallT, ns(onto)); % put back relevant dims of size 1