finally the magic happened !!!
here is the code i used..
col = dts << New Column("Binning", Numeric, Continuous);
Eval( Parse( Eval Insert( "col << Set Formula(:Ceiling( ^n_Bin^ / ^BinSize^) * ^BinSize^)<< eval formula" )) );
Thank You MS for the guidance; what is the diff on f_bin and n_bin i used?
As far as I could tell from reading your code f_Bin refers to a column whereas n_Bin is a string, which is the data type that is safest to use here.
Thank you again, MS. I shall take note on this.