Deleting columns from a table opentext BIRT Report in the beforeFactory

Question

I am trying to delete few columns conditionally from a table from the report design in the beforeFactory script before the report execution starts, but it does not drop the column .

I'm using the below script:

reportContext.getDesignHandle().findElement("table").getColumns().drop(0)

Basically trying find the table content slot and dropping a content at a particular position .