Translate

Try it.

%!
% Draw a box at 72, 72 using translate

% operator box: xcoord ycoord box -
% Creates one inch box at xcoord, ycoord
/box {
   newpath
   moveto
   72 0 rlineto
   0 72 rlineto
   -72 0 rlineto
   closepath
} def

gsave                           % Preserve the old coordinates
  72 72 translate               % Set origin to (72, 72)
  0 0 box stroke                % Draw the box at the new origin
grestore                        % Restore the old coordinates

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