(http://www.starlink.rl.ac.uk/docs/sun95.htx/node213.html)
This means that you have forgotten to `escape' parentheses, probably when defining an NDF section in the UNIX shell. Try inserting a backslash before each parenthesis or enclosing all the special characters inside " " quotes.
% stats myndf\(100:200,\)
% linplot spectrum"(5087.0~30)"
