Hello Ayyappan,

I have been looking into your questions and I can suggest you have a look at our feature browser in the sample XamDataGrid->Layout and Behaviour->Clipboard where you can try by yourself our copy/paste functionality for one, and for multiple selected cells.  

Furthermore you can try the sample under XamDataGrid->Layout and behavior->XamCaluclationManager Integration, where is shown how you can create calculated fields by setting a particular formula for the column.

For additional reference on this matter you can check our online documentation:

http://help.infragistics.com/NetAdvantage/WPF/2011.2/CLR4.0/?page=xamDataGrid_Clipboard_Operations.html

http://help.infragistics.com/NetAdvantage/WPF/2011.2/CLR4.0/?page=Using xamCalculationManager with xamDataGrid.html

If you have any further questions on this matter, please feel free to ask.