BY Statement
- BY variables ;
You can specify a BY statement with PROC VARCOMP to obtain separate
analyses on observations in groups defined by the BY variables. When a
BY statement appears, the procedure expects the input data set to be
sorted in order of the BY variables. The variables
are one or more variables in the input data set.
If your input data set is not sorted in ascending order, use one of
the following alternatives:
- Sort the data using the SORT procedure with a similar BY statement.
- Specify the BY statement option NOTSORTED or DESCENDING
in the BY statement for the VARCOMP procedure.
The NOTSORTED option does not
mean that the data are unsorted but rather that
the data are arranged in groups (according to values
of the BY variables) and that these groups are not
necessarily in alphabetical or increasing numeric order.
- Create an index on the BY variables using the DATASETS procedure
(in base SAS software).
For more information on the BY statement, see the discussion
in SAS Language Reference: Concepts.
For more information on the DATASETS procedure, see the discussion
in the SAS Procedures Guide.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.