function X = getptsample(M)

%X0 = simple_paths(M);
X0 = simpathcover(M);
c = char(X0);
ell = size(c,2);
[X,Y] = reglang_posneg_dense(0,ell,M);
return


X = {};

%SS = {};
for i=1:length(X0)
  R = spath2cell(M,X0{i});
  R1 = {};
  for j=1:length(R)
    r = strrep(R{j},'@','');
    if ~isempty(r)
      R1{end+1}=r;
    end
  end
  RS = list_all_ind_g(R1);
  for j=1:size(RS,1)
    s = RS(j,:);
    %s = cell2str(R,'');
    %s = strrep(s,'@','');
    %SS{end+1} = strrep(s,'@','');
    fprintf('%d of %d: extracting features from %s \n',i,length(X0),s);
    X = [X; getfeatures(s)];
  end
end
X = unique(X);
return


function SS = getfeatures(x)
N = length(x);
%PROGstart(2^N,['extracting features from "' x '"']);
PROGstart(2^N);
SS = repmat({x},2^N,1);
for i=1:2^N
  setstr = dec2bin(i-1,N);
  ii1 = find(setstr=='1');
  
  SS{i} = x(ii1);
  PROGupdate(i);
end
PROGend;
SS = unique(SS);
return