function [p,inds] = getPX(P,m,n,X,ii)
% p = P(X(ii) = x)
% works for all distrubutions P on m^n
if length(ii)==0
  p = 1;
  return
end

dims = repmat([m],[1 n]);
v = repmat({1:m},[1 n]);
for j=1:length(ii)
  v{ii(j)} = X(j);
end
xx = list_all_ind_g(v);
inds = coord2ind(xx,dims);

p = sum(P(inds));
return