EntityDataSource Iterates over result

I am using EntityDataSource to query data from database. I can read data normally through e.Result

 protected void My_OnSelected(object _sender, EntityDataSourceSelectedEventArgs _e)
{
    ...

    from result in _e.Results.Cast<DataType>() ....
    ....
}

I can see that my query works. The result from query should fill a gridview. In my case, before to bind this data to gridView, I need to do some processing and create an anonymous with some files calculated from variables result like

from result in _e.Results.Cast<DataType>() 
select new{
    z = result.x + result.y
}

the problem is that I can set this result to e.Result and then to bind the data. Is there a way to accomplish this behavior?