more examples of DataFrame methods

[cwliu007]

Hi Nick,

Thank you for sharing the DataFrame package. I feel it is quite useful for me. There are several methods provided (as follows), but could you give more concrete examples how to use? I always have difficulty time using them…

Methods for class DataFrame:

DataFrame disp is_column subsref toStruct
addprop getTable numel summary width
columns head remove_cols toArray writetable
details height subsasgn toCell

Static methods:

fromArray fromCell intersect rowfun
fromCSV fromStruct ismember varfun