function new_comm = MatMPI_Comm_dir(old_comm,dir)
% MatMPI_Comm_dir  -  function for changing communication directory.
% 
%  new_comm = MatMPI_Comm_dir(old_comm,dir)
%
  new_comm = old_comm;

  n = new_comm.machine_db.n_machine;

  for i=1:n
    new_comm.machine_db.dir{1,i} = dir;
  end

  new_comm;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% MatlabMPI
% Dr. Jeremy Kepner
% MIT Lincoln Laboratory
% kepner@ll.mit.edu
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Copyright 2002 Massachusetts Institute of Technology
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