keep (dataloop) ============================================== Purpose ---------------- Specifies columns (variables) to be saved to the output dataset in a data loop. .. _keep: .. index:: keep Format ---------------- :: keep variable_list; Examples ---------------- :: keep age, pay, sex; Remarks ------- Commas are optional in *variable_list*. Retains only the specified variables in the output dataset. Any variables referenced must already exist, either as elements of the source dataset, or as the result of a previous `make`, `vector`, or `code` statement. If neither `keep` nor `drop` is used, the output dataset will contain all variables from the source dataset, as well as any newly defined variables. The effects of multiple `keep` and `drop` statements are cumulative. .. seealso:: `drop`